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latency performance problems #4
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ericvh
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Dec 7, 2022
xfstests generic/013 and generic/476 reported WARNING as follows: WARNING: lock held when returning to user space! 6.1.0-rc5+ #4 Not tainted ------------------------------------------------ fsstress/504233 is leaving the kernel with locks still held! 2 locks held by fsstress/504233: #0: ffff888054c38850 (&sb->s_type->i_mutex_key#21){+.+.}-{3:3}, at: lock_two_nondirectories+0xcf/0xf0 #1: ffff8880b8fec750 (&sb->s_type->i_mutex_key#21/4){+.+.}-{3:3}, at: lock_two_nondirectories+0xb7/0xf0 This will lead to deadlock and hungtask. Fix this by releasing locks when failed to write out on a file range in cifs_file_copychunk_range(). Fixes: 3e3761f ("smb3: use filemap_write_and_wait_range instead of filemap_write_and_wait") Cc: stable@vger.kernel.org # 6.0 Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz> Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com> Signed-off-by: Steve French <stfrench@microsoft.com>
ericvh
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Dec 7, 2022
test_bpf tail call tests end up as: test_bpf: #0 Tail call leaf jited:1 85 PASS test_bpf: #1 Tail call 2 jited:1 111 PASS test_bpf: #2 Tail call 3 jited:1 145 PASS test_bpf: #3 Tail call 4 jited:1 170 PASS test_bpf: #4 Tail call load/store leaf jited:1 190 PASS test_bpf: #5 Tail call load/store jited:1 BUG: Unable to handle kernel data access on write at 0xf1b4e000 Faulting instruction address: 0xbe86b710 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K MMU=Hash PowerMac Modules linked in: test_bpf(+) CPU: 0 PID: 97 Comm: insmod Not tainted 6.1.0-rc4+ torvalds#195 Hardware name: PowerMac3,1 750CL 0x87210 PowerMac NIP: be86b710 LR: be857e88 CTR: be86b704 REGS: f1b4df20 TRAP: 0300 Not tainted (6.1.0-rc4+) MSR: 00009032 <EE,ME,IR,DR,RI> CR: 28008242 XER: 00000000 DAR: f1b4e000 DSISR: 42000000 GPR00: 00000001 f1b4dfe c11d2280 00000000 00000000 00000000 00000002 00000000 GPR08: f1b4e000 be86b704 f1b4e000 00000000 00000000 100d816a f2440000 fe73baa8 GPR16: f2458000 00000000 c1941ae4 f1fe2248 00000045 c0de0000 f2458030 00000000 GPR24: 000003e8 0000000f f2458000 f1b4dc90 3e584b46 00000000 f24466a0 c1941a00 NIP [be86b710] 0xbe86b710 LR [be857e88] __run_one+0xec/0x264 [test_bpf] Call Trace: [f1b4dfe] [00000002] 0x2 (unreliable) Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace 0000000000000000 ]--- This is a tentative to write above the stack. The problem is encoutered with tests added by commit 38608ee ("bpf, tests: Add load store test case for tail call") This happens because tail call is done to a BPF prog with a different stack_depth. At the time being, the stack is kept as is when the caller tail calls its callee. But at exit, the callee restores the stack based on its own properties. Therefore here, at each run, r1 is erroneously increased by 32 - 16 = 16 bytes. This was done that way in order to pass the tail call count from caller to callee through the stack. As powerpc32 doesn't have a red zone in the stack, it was necessary the maintain the stack as is for the tail call. But it was not anticipated that the BPF frame size could be different. Let's take a new approach. Use register r4 to carry the tail call count during the tail call, and save it into the stack at function entry if required. This means the input parameter must be in r3, which is more correct as it is a 32 bits parameter, then tail call better match with normal BPF function entry, the down side being that we move that input parameter back and forth between r3 and r4. That can be optimised later. Doing that also has the advantage of maximising the common parts between tail calls and a normal function exit. With the fix, tail call tests are now successfull: test_bpf: #0 Tail call leaf jited:1 53 PASS test_bpf: #1 Tail call 2 jited:1 115 PASS test_bpf: #2 Tail call 3 jited:1 154 PASS test_bpf: #3 Tail call 4 jited:1 165 PASS test_bpf: #4 Tail call load/store leaf jited:1 101 PASS test_bpf: #5 Tail call load/store jited:1 141 PASS test_bpf: #6 Tail call error path, max count reached jited:1 994 PASS test_bpf: #7 Tail call count preserved across function calls jited:1 140975 PASS test_bpf: #8 Tail call error path, NULL target jited:1 110 PASS test_bpf: #9 Tail call error path, index out of range jited:1 69 PASS test_bpf: test_tail_calls: Summary: 10 PASSED, 0 FAILED, [10/10 JIT'ed] Suggested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Fixes: 51c66ad ("powerpc/bpf: Implement extended BPF on PPC32") Cc: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/757acccb7fbfc78efa42dcf3c974b46678198905.1669278887.git.christophe.leroy@csgroup.eu
ericvh
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Dec 7, 2022
QAT devices on Intel Sapphire Rapids and Emerald Rapids have a defect in address translation service (ATS). These devices may inadvertently issue ATS invalidation completion before posted writes initiated with translated address that utilized translations matching the invalidation address range, violating the invalidation completion ordering. This patch adds an extra device TLB invalidation for the affected devices, it is needed to ensure no more posted writes with translated address following the invalidation completion. Therefore, the ordering is preserved and data-corruption is prevented. Device TLBs are invalidated under the following six conditions: 1. Device driver does DMA API unmap IOVA 2. Device driver unbind a PASID from a process, sva_unbind_device() 3. PASID is torn down, after PASID cache is flushed. e.g. process exit_mmap() due to crash 4. Under SVA usage, called by mmu_notifier.invalidate_range() where VM has to free pages that were unmapped 5. userspace driver unmaps a DMA buffer 6. Cache invalidation in vSVA usage (upcoming) For #1 and #2, device drivers are responsible for stopping DMA traffic before unmap/unbind. For #3, iommu driver gets mmu_notifier to invalidate TLB the same way as normal user unmap which will do an extra invalidation. The dTLB invalidation after PASID cache flush does not need an extra invalidation. Therefore, we only need to deal with #4 and #5 in this patch. #1 is also covered by this patch due to common code path with #5. Tested-by: Yuzhang Luo <yuzhang.luo@intel.com> Reviewed-by: Ashok Raj <ashok.raj@intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Link: https://lore.kernel.org/r/20221130062449.1360063-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
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ericvh
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Dec 17, 2022
We need to check if we have a OS prefix, otherwise we stumble on a metric segv that I'm now seeing in Arnaldo's tree: $ gdb --args perf stat -M Backend true ... Performance counter stats for 'true': 4,712,355 TOPDOWN.SLOTS # 17.3 % tma_core_bound Program received signal SIGSEGV, Segmentation fault. __strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77 77 ../sysdeps/x86_64/multiarch/strlen-evex.S: No such file or directory. (gdb) bt #0 __strlen_evex () at ../sysdeps/x86_64/multiarch/strlen-evex.S:77 #1 0x00007ffff74749a5 in __GI__IO_fputs (str=0x0, fp=0x7ffff75f5680 <_IO_2_1_stderr_>) #2 0x0000555555779f28 in do_new_line_std (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10) at util/stat-display.c:356 #3 0x000055555577a081 in print_metric_std (config=0x555555e077c0 <stat_config>, ctx=0x7fffffffbf10, color=0x0, fmt=0x5555558b77b5 "%8.1f", unit=0x7fffffffbb10 "% tma_memory_bound", val=13.165355724442199) at util/stat-display.c:380 #4 0x00005555557768b6 in generic_metric (config=0x555555e077c0 <stat_config>, metric_expr=0x55555593d5b7 "((CYCLE_ACTIVITY.STALLS_MEM_ANY + EXE_ACTIVITY.BOUND_ON_STORES) / (CYCLE_ACTIVITY.STALLS_TOTAL + (EXE_ACTIVITY.1_PORTS_UTIL + tma_retiring * EXE_ACTIVITY.2_PORTS_UTIL) + EXE_ACTIVITY.BOUND_ON_STORES))"..., metric_events=0x555555f334e0, metric_refs=0x555555ec81d0, name=0x555555f32e80 "TOPDOWN.SLOTS", metric_name=0x555555f26c80 "tma_memory_bound", metric_unit=0x55555593d5b1 "100%", runtime=0, map_idx=0, out=0x7fffffffbd90, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:934 #5 0x0000555555778cac in perf_stat__print_shadow_stats (config=0x555555e077c0 <stat_config>, evsel=0x555555f289d0, avg=4712355, map_idx=0, out=0x7fffffffbd90, metric_events=0x555555e078e8 <stat_config+296>, st=0x555555e9e620 <rt_stat>) at util/stat-shadow.c:1329 #6 0x000055555577b6a0 in printout (config=0x555555e077c0 <stat_config>, os=0x7fffffffbf10, uval=4712355, run=325322, ena=325322, noise=4712355, map_idx=0) at util/stat-display.c:741 #7 0x000055555577bc74 in print_counter_aggrdata (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, s=0, os=0x7fffffffbf10) at util/stat-display.c:838 #8 0x000055555577c1d8 in print_counter (config=0x555555e077c0 <stat_config>, counter=0x555555f289d0, os=0x7fffffffbf10) at util/stat-display.c:957 #9 0x000055555577dba0 in evlist__print_counters (evlist=0x555555ec3610, config=0x555555e077c0 <stat_config>, _target=0x555555e01c80 <target>, ts=0x0, argc=1, argv=0x7fffffffe450) at util/stat-display.c:1413 #10 0x00005555555fc821 in print_counters (ts=0x0, argc=1, argv=0x7fffffffe450) at builtin-stat.c:1040 #11 0x000055555560091a in cmd_stat (argc=1, argv=0x7fffffffe450) at builtin-stat.c:2665 #12 0x00005555556b1eea in run_builtin (p=0x555555e11f70 <commands+336>, argc=4, argv=0x7fffffffe450) at perf.c:322 #13 0x00005555556b2181 in handle_internal_command (argc=4, argv=0x7fffffffe450) at perf.c:376 #14 0x00005555556b22d7 in run_argv (argcp=0x7fffffffe27c, argv=0x7fffffffe270) at perf.c:420 #15 0x00005555556b26ef in main (argc=4, argv=0x7fffffffe450) at perf.c:550 (gdb) Fixes: f123b2d ("perf stat: Remove prefix argument in print_metric_headers()") Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Xing Zhengjun <zhengjun.xing@linux.intel.com> Link: http://lore.kernel.org/lkml/CAP-5=fUOjSM5HajU9TCD6prY39LbX4OQbkEbtKPPGRBPBN=_VQ@mail.gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
first part of this fixed as of f07a6bb -- but still need to address coherence and meta-data operations |
ericvh
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Apr 26, 2023
…kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.3, part #4 - Plug a buffer overflow due to the use of the user-provided register width for firmware regs. Outright reject accesses where the user register width does not match the kernel representation. - Protect non-atomic RMW operations on vCPU flags against preemption, as an update to the flags by an intervening preemption could be lost.
ericvh
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May 7, 2023
Error handler of tcf_block_bind() frees the whole bo->cb_list on error. However, by that time the flow_block_cb instances are already in the driver list because driver ndo_setup_tc() callback is called before that up the call chain in tcf_block_offload_cmd(). This leaves dangling pointers to freed objects in the list and causes use-after-free[0]. Fix it by also removing flow_block_cb instances from driver_list before deallocating them. [0]: [ 279.868433] ================================================================== [ 279.869964] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x631/0x7c0 [ 279.871527] Read of size 8 at addr ffff888147e2bf20 by task tc/2963 [ 279.873151] CPU: 6 PID: 2963 Comm: tc Not tainted 6.3.0-rc6+ #4 [ 279.874273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 279.876295] Call Trace: [ 279.876882] <TASK> [ 279.877413] dump_stack_lvl+0x33/0x50 [ 279.878198] print_report+0xc2/0x610 [ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.879994] kasan_report+0xae/0xe0 [ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core] [ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0 [ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.885037] ? tcf_block_setup+0x6b0/0x6b0 [ 279.885901] ? mutex_lock+0x7d/0xd0 [ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0 [ 279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress] [ 279.888846] tcf_block_get_ext+0x61c/0x1200 [ 279.889711] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress] [ 279.891701] qdisc_create+0x401/0xea0 [ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470 [ 279.893473] tc_modify_qdisc+0x6f7/0x16d0 [ 279.894344] ? tc_get_qdisc+0xac0/0xac0 [ 279.895213] ? mutex_lock+0x7d/0xd0 [ 279.896005] ? __mutex_lock_slowpath+0x10/0x10 [ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.898672] ? __sys_sendmsg+0xb5/0x140 [ 279.899494] ? do_syscall_64+0x3d/0x90 [ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.901337] ? kasan_save_stack+0x2e/0x40 [ 279.902177] ? kasan_save_stack+0x1e/0x40 [ 279.903058] ? kasan_set_track+0x21/0x30 [ 279.903913] ? kasan_save_free_info+0x2a/0x40 [ 279.904836] ? ____kasan_slab_free+0x11a/0x1b0 [ 279.905741] ? kmem_cache_free+0x179/0x400 [ 279.906599] netlink_rcv_skb+0x12c/0x360 [ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.908360] ? netlink_ack+0x1550/0x1550 [ 279.909192] ? rhashtable_walk_peek+0x170/0x170 [ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390 [ 279.911086] ? _copy_from_iter+0x3d6/0xc70 [ 279.912031] netlink_unicast+0x553/0x790 [ 279.912864] ? netlink_attachskb+0x6a0/0x6a0 [ 279.913763] ? netlink_recvmsg+0x416/0xb50 [ 279.914627] netlink_sendmsg+0x7a1/0xcb0 [ 279.915473] ? netlink_unicast+0x790/0x790 [ 279.916334] ? iovec_from_user.part.0+0x4d/0x220 [ 279.917293] ? netlink_unicast+0x790/0x790 [ 279.918159] sock_sendmsg+0xc5/0x190 [ 279.918938] ____sys_sendmsg+0x535/0x6b0 [ 279.919813] ? import_iovec+0x7/0x10 [ 279.920601] ? kernel_sendmsg+0x30/0x30 [ 279.921423] ? __copy_msghdr+0x3c0/0x3c0 [ 279.922254] ? import_iovec+0x7/0x10 [ 279.923041] ___sys_sendmsg+0xeb/0x170 [ 279.923854] ? copy_msghdr_from_user+0x110/0x110 [ 279.924797] ? ___sys_recvmsg+0xd9/0x130 [ 279.925630] ? __perf_event_task_sched_in+0x183/0x470 [ 279.926656] ? ___sys_sendmsg+0x170/0x170 [ 279.927529] ? ctx_sched_in+0x530/0x530 [ 279.928369] ? update_curr+0x283/0x4f0 [ 279.929185] ? perf_event_update_userpage+0x570/0x570 [ 279.930201] ? __fget_light+0x57/0x520 [ 279.931023] ? __switch_to+0x53d/0xe70 [ 279.931846] ? sockfd_lookup_light+0x1a/0x140 [ 279.932761] __sys_sendmsg+0xb5/0x140 [ 279.933560] ? __sys_sendmsg_sock+0x20/0x20 [ 279.934436] ? fpregs_assert_state_consistent+0x1d/0xa0 [ 279.935490] do_syscall_64+0x3d/0x90 [ 279.936300] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.937311] RIP: 0033:0x7f21c814f887 [ 279.938085] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 [ 279.941448] RSP: 002b:00007fff11efd478 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 279.942964] RAX: ffffffffffffffda RBX: 0000000064401979 RCX: 00007f21c814f887 [ 279.944337] RDX: 0000000000000000 RSI: 00007fff11efd4e0 RDI: 0000000000000003 [ 279.945660] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 [ 279.947003] R10: 00007f21c8008708 R11: 0000000000000246 R12: 0000000000000001 [ 279.948345] R13: 0000000000409980 R14: 000000000047e538 R15: 0000000000485400 [ 279.949690] </TASK> [ 279.950706] Allocated by task 2960: [ 279.951471] kasan_save_stack+0x1e/0x40 [ 279.952338] kasan_set_track+0x21/0x30 [ 279.953165] __kasan_kmalloc+0x77/0x90 [ 279.954006] flow_block_cb_setup_simple+0x3dd/0x7c0 [ 279.955001] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.956020] tcf_block_get_ext+0x61c/0x1200 [ 279.956881] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.957873] qdisc_create+0x401/0xea0 [ 279.958656] tc_modify_qdisc+0x6f7/0x16d0 [ 279.959506] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.960392] netlink_rcv_skb+0x12c/0x360 [ 279.961216] netlink_unicast+0x553/0x790 [ 279.962044] netlink_sendmsg+0x7a1/0xcb0 [ 279.962906] sock_sendmsg+0xc5/0x190 [ 279.963702] ____sys_sendmsg+0x535/0x6b0 [ 279.964534] ___sys_sendmsg+0xeb/0x170 [ 279.965343] __sys_sendmsg+0xb5/0x140 [ 279.966132] do_syscall_64+0x3d/0x90 [ 279.966908] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.968407] Freed by task 2960: [ 279.969114] kasan_save_stack+0x1e/0x40 [ 279.969929] kasan_set_track+0x21/0x30 [ 279.970729] kasan_save_free_info+0x2a/0x40 [ 279.971603] ____kasan_slab_free+0x11a/0x1b0 [ 279.972483] __kmem_cache_free+0x14d/0x280 [ 279.973337] tcf_block_setup+0x29d/0x6b0 [ 279.974173] tcf_block_offload_cmd.isra.0+0x226/0x2d0 [ 279.975186] tcf_block_get_ext+0x61c/0x1200 [ 279.976080] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.977065] qdisc_create+0x401/0xea0 [ 279.977857] tc_modify_qdisc+0x6f7/0x16d0 [ 279.978695] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.979562] netlink_rcv_skb+0x12c/0x360 [ 279.980388] netlink_unicast+0x553/0x790 [ 279.981214] netlink_sendmsg+0x7a1/0xcb0 [ 279.982043] sock_sendmsg+0xc5/0x190 [ 279.982827] ____sys_sendmsg+0x535/0x6b0 [ 279.983703] ___sys_sendmsg+0xeb/0x170 [ 279.984510] __sys_sendmsg+0xb5/0x140 [ 279.985298] do_syscall_64+0x3d/0x90 [ 279.986076] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.987532] The buggy address belongs to the object at ffff888147e2bf00 which belongs to the cache kmalloc-192 of size 192 [ 279.989747] The buggy address is located 32 bytes inside of freed 192-byte region [ffff888147e2bf00, ffff888147e2bfc0) [ 279.992367] The buggy address belongs to the physical page: [ 279.993430] page:00000000550f405c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147e2a [ 279.995182] head:00000000550f405c order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 279.996713] anon flags: 0x200000000010200(slab|head|node=0|zone=2) [ 279.997878] raw: 0200000000010200 ffff888100042a00 0000000000000000 dead000000000001 [ 279.999384] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [ 280.000894] page dumped because: kasan: bad access detected [ 280.002386] Memory state around the buggy address: [ 280.003338] ffff888147e2be00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.004781] ffff888147e2be80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 280.006224] >ffff888147e2bf00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.007700] ^ [ 280.008592] ffff888147e2bf80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 280.010035] ffff888147e2c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.011564] ================================================================== Fixes: 59094b1 ("net: sched: use flow block API") Signed-off-by: Vlad Buslov <vladbu@nvidia.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
ericvh
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May 7, 2023
When booting with 'kasan.vmalloc=off', a kernel configured with support for KASAN_HW_TAGS will explode at boot time due to bogus use of virt_to_page() on a vmalloc adddress. With CONFIG_DEBUG_VIRTUAL selected this will be reported explicitly, and with or without CONFIG_DEBUG_VIRTUAL the kernel will dereference a bogus address: | ------------[ cut here ]------------ | virt_to_phys used for non-linear address: (____ptrval____) (0xffff800008000000) | WARNING: CPU: 0 PID: 0 at arch/arm64/mm/physaddr.c:15 __virt_to_phys+0x78/0x80 | Modules linked in: | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.3.0-rc3-00073-g83865133300d-dirty #4 | Hardware name: linux,dummy-virt (DT) | pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : __virt_to_phys+0x78/0x80 | lr : __virt_to_phys+0x78/0x80 | sp : ffffcd076afd3c80 | x29: ffffcd076afd3c80 x28: 0068000000000f07 x27: ffff800008000000 | x26: fffffbfff0000000 x25: fffffbffff000000 x24: ff00000000000000 | x23: ffffcd076ad3c000 x22: fffffc0000000000 x21: ffff800008000000 | x20: ffff800008004000 x19: ffff800008000000 x18: ffff800008004000 | x17: 666678302820295f x16: ffffffffffffffff x15: 0000000000000004 | x14: ffffcd076b009e88 x13: 0000000000000fff x12: 0000000000000003 | x11: 00000000ffffefff x10: c0000000ffffefff x9 : 0000000000000000 | x8 : 0000000000000000 x7 : 205d303030303030 x6 : 302e30202020205b | x5 : ffffcd076b41d63f x4 : ffffcd076afd3827 x3 : 0000000000000000 | x2 : 0000000000000000 x1 : ffffcd076afd3a30 x0 : 000000000000004f | Call trace: | __virt_to_phys+0x78/0x80 | __kasan_unpoison_vmalloc+0xd4/0x478 | __vmalloc_node_range+0x77c/0x7b8 | __vmalloc_node+0x54/0x64 | init_IRQ+0x94/0xc8 | start_kernel+0x194/0x420 | __primary_switched+0xbc/0xc4 | ---[ end trace 0000000000000000 ]--- | Unable to handle kernel paging request at virtual address 03fffacbe27b8000 | Mem abort info: | ESR = 0x0000000096000004 | EC = 0x25: DABT (current EL), IL = 32 bits | SET = 0, FnV = 0 | EA = 0, S1PTW = 0 | FSC = 0x04: level 0 translation fault | Data abort info: | ISV = 0, ISS = 0x00000004 | CM = 0, WnR = 0 | swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000041bc5000 | [03fffacbe27b8000] pgd=0000000000000000, p4d=0000000000000000 | Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP | Modules linked in: | CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 6.3.0-rc3-00073-g83865133300d-dirty #4 | Hardware name: linux,dummy-virt (DT) | pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) | pc : __kasan_unpoison_vmalloc+0xe4/0x478 | lr : __kasan_unpoison_vmalloc+0xd4/0x478 | sp : ffffcd076afd3ca0 | x29: ffffcd076afd3ca0 x28: 0068000000000f07 x27: ffff800008000000 | x26: 0000000000000000 x25: 03fffacbe27b8000 x24: ff00000000000000 | x23: ffffcd076ad3c000 x22: fffffc0000000000 x21: ffff800008000000 | x20: ffff800008004000 x19: ffff800008000000 x18: ffff800008004000 | x17: 666678302820295f x16: ffffffffffffffff x15: 0000000000000004 | x14: ffffcd076b009e88 x13: 0000000000000fff x12: 0000000000000001 | x11: 0000800008000000 x10: ffff800008000000 x9 : ffffb2f8dee00000 | x8 : 000ffffb2f8dee00 x7 : 205d303030303030 x6 : 302e30202020205b | x5 : ffffcd076b41d63f x4 : ffffcd076afd3827 x3 : 0000000000000000 | x2 : 0000000000000000 x1 : ffffcd076afd3a30 x0 : ffffb2f8dee00000 | Call trace: | __kasan_unpoison_vmalloc+0xe4/0x478 | __vmalloc_node_range+0x77c/0x7b8 | __vmalloc_node+0x54/0x64 | init_IRQ+0x94/0xc8 | start_kernel+0x194/0x420 | __primary_switched+0xbc/0xc4 | Code: d34cfc08 aa1f03fa 8b081b39 d503201f (f9400328) | ---[ end trace 0000000000000000 ]--- | Kernel panic - not syncing: Attempted to kill the idle task! This is because init_vmalloc_pages() erroneously calls virt_to_page() on a vmalloc address, while virt_to_page() is only valid for addresses in the linear/direct map. Since init_vmalloc_pages() expects virtual addresses in the vmalloc range, it must use vmalloc_to_page() rather than virt_to_page(). We call init_vmalloc_pages() from __kasan_unpoison_vmalloc(), where we check !is_vmalloc_or_module_addr(), suggesting that we might encounter a non-vmalloc address. Luckily, this never happens. By design, we only call __kasan_unpoison_vmalloc() on pointers in the vmalloc area, and I have verified that we don't violate that expectation. Given that, is_vmalloc_or_module_addr() must always be true for any legitimate argument to __kasan_unpoison_vmalloc(). Correct init_vmalloc_pages() to use vmalloc_to_page(), and remove the redundant and misleading use of is_vmalloc_or_module_addr() in __kasan_unpoison_vmalloc(). Link: https://lkml.kernel.org/r/20230418164212.1775741-1-mark.rutland@arm.com Fixes: 6c2f761 ("kasan: fix zeroing vmalloc memory with HW_TAGS") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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Sai Krishna says: ==================== octeontx2: Miscellaneous fixes This patchset includes following fixes. Patch #1 Fix for the race condition while updating APR table Patch #2 Fix end bit position in NPC scan config Patch #3 Fix depth of CAM, MEM table entries Patch #4 Fix in increase the size of DMAC filter flows Patch #5 Fix driver crash resulting from invalid interface type information retrieved from firmware Patch #6 Fix incorrect mask used while installing filters involving fragmented packets Patch #7 Fixes for NPC field hash extract w.r.t IPV6 hash reduction, IPV6 filed hash configuration. Patch #8 Fix for NPC hardware parser configuration destination address hash, IPV6 endianness issues. Patch #9 Fix for skipping mbox initialization for PFs disabled by firmware. Patch #10 Fix disabling packet I/O in case of mailbox timeout. Patch #11 Fix detaching LF resources in case of VF probe fail. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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…linux/kernel/git/tip/tip Pull SMP updates from Thomas Gleixner: "A large update for SMP management: - Parallel CPU bringup The reason why people are interested in parallel bringup is to shorten the (kexec) reboot time of cloud servers to reduce the downtime of the VM tenants. The current fully serialized bringup does the following per AP: 1) Prepare callbacks (allocate, intialize, create threads) 2) Kick the AP alive (e.g. INIT/SIPI on x86) 3) Wait for the AP to report alive state 4) Let the AP continue through the atomic bringup 5) Let the AP run the threaded bringup to full online state There are two significant delays: #3 The time for an AP to report alive state in start_secondary() on x86 has been measured in the range between 350us and 3.5ms depending on vendor and CPU type, BIOS microcode size etc. #4 The atomic bringup does the microcode update. This has been measured to take up to ~8ms on the primary threads depending on the microcode patch size to apply. On a two socket SKL server with 56 cores (112 threads) the boot CPU spends on current mainline about 800ms busy waiting for the APs to come up and apply microcode. That's more than 80% of the actual onlining procedure. This can be reduced significantly by splitting the bringup mechanism into two parts: 1) Run the prepare callbacks and kick the AP alive for each AP which needs to be brought up. The APs wake up, do their firmware initialization and run the low level kernel startup code including microcode loading in parallel up to the first synchronization point. (#1 and #2 above) 2) Run the rest of the bringup code strictly serialized per CPU (#3 - #5 above) as it's done today. Parallelizing that stage of the CPU bringup might be possible in theory, but it's questionable whether required surgery would be justified for a pretty small gain. If the system is large enough the first AP is already waiting at the first synchronization point when the boot CPU finished the wake-up of the last AP. That reduces the AP bringup time on that SKL from ~800ms to ~80ms, i.e. by a factor ~10x. The actual gain varies wildly depending on the system, CPU, microcode patch size and other factors. There are some opportunities to reduce the overhead further, but that needs some deep surgery in the x86 CPU bringup code. For now this is only enabled on x86, but the core functionality obviously works for all SMP capable architectures. - Enhancements for SMP function call tracing so it is possible to locate the scheduling and the actual execution points. That allows to measure IPI delivery time precisely" * tag 'smp-core-2023-06-26' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits) trace,smp: Add tracepoints for scheduling remotelly called functions trace,smp: Add tracepoints around remotelly called functions MAINTAINERS: Add CPU HOTPLUG entry x86/smpboot: Fix the parallel bringup decision x86/realmode: Make stack lock work in trampoline_compat() x86/smp: Initialize cpu_primary_thread_mask late cpu/hotplug: Fix off by one in cpuhp_bringup_mask() x86/apic: Fix use of X{,2}APIC_ENABLE in asm with older binutils x86/smpboot/64: Implement arch_cpuhp_init_parallel_bringup() and enable it x86/smpboot: Support parallel startup of secondary CPUs x86/smpboot: Implement a bit spinlock to protect the realmode stack x86/apic: Save the APIC virtual base address cpu/hotplug: Allow "parallel" bringup up to CPUHP_BP_KICK_AP_STATE x86/apic: Provide cpu_primary_thread mask x86/smpboot: Enable split CPU startup cpu/hotplug: Provide a split up CPUHP_BRINGUP mechanism cpu/hotplug: Reset task stack state in _cpu_up() cpu/hotplug: Remove unused state functions riscv: Switch to hotplug core state synchronization parisc: Switch to hotplug core state synchronization ...
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ni_create_attr_list uses WARN_ON to catch error cases while generating attribute list, which only prints out stack trace and may not be enough. This repalces them with more proper error handling flow. [ 59.666332] BUG: kernel NULL pointer dereference, address: 000000000000000e [ 59.673268] #PF: supervisor read access in kernel mode [ 59.678354] #PF: error_code(0x0000) - not-present page [ 59.682831] PGD 8000000005ff1067 P4D 8000000005ff1067 PUD 7dee067 PMD 0 [ 59.688556] Oops: 0000 [#1] PREEMPT SMP KASAN PTI [ 59.692642] CPU: 0 PID: 198 Comm: poc Tainted: G B W 6.2.0-rc1+ #4 [ 59.698868] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 59.708795] RIP: 0010:ni_create_attr_list+0x505/0x860 [ 59.713657] Code: 7e 10 e8 5e d0 d0 ff 45 0f b7 76 10 48 8d 7b 16 e8 00 d1 d0 ff 66 44 89 73 16 4d 8d 75 0e 4c 89 f7 e8 3f d0 d0 ff 4c 8d8 [ 59.731559] RSP: 0018:ffff88800a56f1e0 EFLAGS: 00010282 [ 59.735691] RAX: 0000000000000001 RBX: ffff88800b7b5088 RCX: ffffffffb83079fe [ 59.741792] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffbb7f9fc0 [ 59.748423] RBP: ffff88800a56f3a8 R08: ffff88800b7b50a0 R09: fffffbfff76ff3f9 [ 59.754654] R10: ffffffffbb7f9fc7 R11: fffffbfff76ff3f8 R12: ffff88800b756180 [ 59.761552] R13: 0000000000000000 R14: 000000000000000e R15: 0000000000000050 [ 59.768323] FS: 00007feaa8c96440(0000) GS:ffff88806d400000(0000) knlGS:0000000000000000 [ 59.776027] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.781395] CR2: 00007f3a2e0b1000 CR3: 000000000a5bc000 CR4: 00000000000006f0 [ 59.787607] Call Trace: [ 59.790271] <TASK> [ 59.792488] ? __pfx_ni_create_attr_list+0x10/0x10 [ 59.797235] ? kernel_text_address+0xd3/0xe0 [ 59.800856] ? unwind_get_return_address+0x3e/0x60 [ 59.805101] ? __kasan_check_write+0x18/0x20 [ 59.809296] ? preempt_count_sub+0x1c/0xd0 [ 59.813421] ni_ins_attr_ext+0x52c/0x5c0 [ 59.817034] ? __pfx_ni_ins_attr_ext+0x10/0x10 [ 59.821926] ? __vfs_setxattr+0x121/0x170 [ 59.825718] ? __vfs_setxattr_noperm+0x97/0x300 [ 59.829562] ? __vfs_setxattr_locked+0x145/0x170 [ 59.833987] ? vfs_setxattr+0x137/0x2a0 [ 59.836732] ? do_setxattr+0xce/0x150 [ 59.839807] ? setxattr+0x126/0x140 [ 59.842353] ? path_setxattr+0x164/0x180 [ 59.845275] ? __x64_sys_setxattr+0x71/0x90 [ 59.848838] ? do_syscall_64+0x3f/0x90 [ 59.851898] ? entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 59.857046] ? stack_depot_save+0x17/0x20 [ 59.860299] ni_insert_attr+0x1ba/0x420 [ 59.863104] ? __pfx_ni_insert_attr+0x10/0x10 [ 59.867069] ? preempt_count_sub+0x1c/0xd0 [ 59.869897] ? _raw_spin_unlock_irqrestore+0x2b/0x50 [ 59.874088] ? __create_object+0x3ae/0x5d0 [ 59.877865] ni_insert_resident+0xc4/0x1c0 [ 59.881430] ? __pfx_ni_insert_resident+0x10/0x10 [ 59.886355] ? kasan_save_alloc_info+0x1f/0x30 [ 59.891117] ? __kasan_kmalloc+0x8b/0xa0 [ 59.894383] ntfs_set_ea+0x90d/0xbf0 [ 59.897703] ? __pfx_ntfs_set_ea+0x10/0x10 [ 59.901011] ? kernel_text_address+0xd3/0xe0 [ 59.905308] ? __kernel_text_address+0x16/0x50 [ 59.909811] ? unwind_get_return_address+0x3e/0x60 [ 59.914898] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 59.920250] ? arch_stack_walk+0xa2/0x100 [ 59.924560] ? filter_irq_stacks+0x27/0x80 [ 59.928722] ntfs_setxattr+0x405/0x440 [ 59.932512] ? __pfx_ntfs_setxattr+0x10/0x10 [ 59.936634] ? kvmalloc_node+0x2d/0x120 [ 59.940378] ? kasan_save_stack+0x41/0x60 [ 59.943870] ? kasan_save_stack+0x2a/0x60 [ 59.947719] ? kasan_set_track+0x29/0x40 [ 59.951417] ? kasan_save_alloc_info+0x1f/0x30 [ 59.955733] ? __kasan_kmalloc+0x8b/0xa0 [ 59.959598] ? __kmalloc_node+0x68/0x150 [ 59.963163] ? kvmalloc_node+0x2d/0x120 [ 59.966490] ? vmemdup_user+0x2b/0xa0 [ 59.969060] __vfs_setxattr+0x121/0x170 [ 59.972456] ? __pfx___vfs_setxattr+0x10/0x10 [ 59.976008] __vfs_setxattr_noperm+0x97/0x300 [ 59.981562] __vfs_setxattr_locked+0x145/0x170 [ 59.986100] vfs_setxattr+0x137/0x2a0 [ 59.989964] ? __pfx_vfs_setxattr+0x10/0x10 [ 59.993616] ? __kasan_check_write+0x18/0x20 [ 59.997425] do_setxattr+0xce/0x150 [ 60.000304] setxattr+0x126/0x140 [ 60.002967] ? __pfx_setxattr+0x10/0x10 [ 60.006471] ? __virt_addr_valid+0xcb/0x140 [ 60.010461] ? __call_rcu_common.constprop.0+0x1c7/0x330 [ 60.016037] ? debug_smp_processor_id+0x1b/0x30 [ 60.021008] ? kasan_quarantine_put+0x5b/0x190 [ 60.025545] ? putname+0x84/0xa0 [ 60.027910] ? __kasan_slab_free+0x11e/0x1b0 [ 60.031483] ? putname+0x84/0xa0 [ 60.033986] ? preempt_count_sub+0x1c/0xd0 [ 60.036876] ? __mnt_want_write+0xae/0x100 [ 60.040738] ? mnt_want_write+0x8f/0x150 [ 60.044317] path_setxattr+0x164/0x180 [ 60.048096] ? __pfx_path_setxattr+0x10/0x10 [ 60.052096] ? strncpy_from_user+0x175/0x1c0 [ 60.056482] ? debug_smp_processor_id+0x1b/0x30 [ 60.059848] ? fpregs_assert_state_consistent+0x6b/0x80 [ 60.064557] __x64_sys_setxattr+0x71/0x90 [ 60.068892] do_syscall_64+0x3f/0x90 [ 60.072868] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 60.077523] RIP: 0033:0x7feaa86e4469 [ 60.080915] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 088 [ 60.097353] RSP: 002b:00007ffdbd8311e8 EFLAGS: 00000286 ORIG_RAX: 00000000000000bc [ 60.103386] RAX: ffffffffffffffda RBX: 9461c5e290baac00 RCX: 00007feaa86e4469 [ 60.110322] RDX: 00007ffdbd831fe0 RSI: 00007ffdbd831305 RDI: 00007ffdbd831263 [ 60.116808] RBP: 00007ffdbd836180 R08: 0000000000000001 R09: 00007ffdbd836268 [ 60.123879] R10: 000000000000007d R11: 0000000000000286 R12: 0000000000400500 [ 60.130540] R13: 00007ffdbd836260 R14: 0000000000000000 R15: 0000000000000000 [ 60.136553] </TASK> [ 60.138818] Modules linked in: [ 60.141839] CR2: 000000000000000e [ 60.144831] ---[ end trace 0000000000000000 ]--- [ 60.149058] RIP: 0010:ni_create_attr_list+0x505/0x860 [ 60.153975] Code: 7e 10 e8 5e d0 d0 ff 45 0f b7 76 10 48 8d 7b 16 e8 00 d1 d0 ff 66 44 89 73 16 4d 8d 75 0e 4c 89 f7 e8 3f d0 d0 ff 4c 8d8 [ 60.172443] RSP: 0018:ffff88800a56f1e0 EFLAGS: 00010282 [ 60.176246] RAX: 0000000000000001 RBX: ffff88800b7b5088 RCX: ffffffffb83079fe [ 60.182752] RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffffffffbb7f9fc0 [ 60.189949] RBP: ffff88800a56f3a8 R08: ffff88800b7b50a0 R09: fffffbfff76ff3f9 [ 60.196950] R10: ffffffffbb7f9fc7 R11: fffffbfff76ff3f8 R12: ffff88800b756180 [ 60.203671] R13: 0000000000000000 R14: 000000000000000e R15: 0000000000000050 [ 60.209595] FS: 00007feaa8c96440(0000) GS:ffff88806d400000(0000) knlGS:0000000000000000 [ 60.216299] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 60.222276] CR2: 00007f3a2e0b1000 CR3: 000000000a5bc000 CR4: 00000000000006f0 Signed-off-by: Edward Lo <loyuantsung@gmail.com> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
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ntfs_read_ea is called when we want to read extended attributes. There are some sanity checks for the validity of the EAs. However, it fails to return a proper error code for the inconsistent attributes, which might lead to unpredicted memory accesses after return. [ 138.916927] BUG: KASAN: use-after-free in ntfs_set_ea+0x453/0xbf0 [ 138.923876] Write of size 4 at addr ffff88800205cfac by task poc/199 [ 138.931132] [ 138.933016] CPU: 0 PID: 199 Comm: poc Not tainted 6.2.0-rc1+ #4 [ 138.938070] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 [ 138.947327] Call Trace: [ 138.949557] <TASK> [ 138.951539] dump_stack_lvl+0x4d/0x67 [ 138.956834] print_report+0x16f/0x4a6 [ 138.960798] ? ntfs_set_ea+0x453/0xbf0 [ 138.964437] ? kasan_complete_mode_report_info+0x7d/0x200 [ 138.969793] ? ntfs_set_ea+0x453/0xbf0 [ 138.973523] kasan_report+0xb8/0x140 [ 138.976740] ? ntfs_set_ea+0x453/0xbf0 [ 138.980578] __asan_store4+0x76/0xa0 [ 138.984669] ntfs_set_ea+0x453/0xbf0 [ 138.988115] ? __pfx_ntfs_set_ea+0x10/0x10 [ 138.993390] ? kernel_text_address+0xd3/0xe0 [ 138.998270] ? __kernel_text_address+0x16/0x50 [ 139.002121] ? unwind_get_return_address+0x3e/0x60 [ 139.005659] ? __pfx_stack_trace_consume_entry+0x10/0x10 [ 139.010177] ? arch_stack_walk+0xa2/0x100 [ 139.013657] ? filter_irq_stacks+0x27/0x80 [ 139.017018] ntfs_setxattr+0x405/0x440 [ 139.022151] ? __pfx_ntfs_setxattr+0x10/0x10 [ 139.026569] ? kvmalloc_node+0x2d/0x120 [ 139.030329] ? kasan_save_stack+0x41/0x60 [ 139.033883] ? kasan_save_stack+0x2a/0x60 [ 139.037338] ? kasan_set_track+0x29/0x40 [ 139.040163] ? kasan_save_alloc_info+0x1f/0x30 [ 139.043588] ? __kasan_kmalloc+0x8b/0xa0 [ 139.047255] ? __kmalloc_node+0x68/0x150 [ 139.051264] ? kvmalloc_node+0x2d/0x120 [ 139.055301] ? vmemdup_user+0x2b/0xa0 [ 139.058584] __vfs_setxattr+0x121/0x170 [ 139.062617] ? __pfx___vfs_setxattr+0x10/0x10 [ 139.066282] __vfs_setxattr_noperm+0x97/0x300 [ 139.070061] __vfs_setxattr_locked+0x145/0x170 [ 139.073580] vfs_setxattr+0x137/0x2a0 [ 139.076641] ? __pfx_vfs_setxattr+0x10/0x10 [ 139.080223] ? __kasan_check_write+0x18/0x20 [ 139.084234] do_setxattr+0xce/0x150 [ 139.087768] setxattr+0x126/0x140 [ 139.091250] ? __pfx_setxattr+0x10/0x10 [ 139.094948] ? __virt_addr_valid+0xcb/0x140 [ 139.097838] ? __call_rcu_common.constprop.0+0x1c7/0x330 [ 139.102688] ? debug_smp_processor_id+0x1b/0x30 [ 139.105985] ? kasan_quarantine_put+0x5b/0x190 [ 139.109980] ? putname+0x84/0xa0 [ 139.113886] ? __kasan_slab_free+0x11e/0x1b0 [ 139.117961] ? putname+0x84/0xa0 [ 139.121316] ? preempt_count_sub+0x1c/0xd0 [ 139.124427] ? __mnt_want_write+0xae/0x100 [ 139.127836] ? mnt_want_write+0x8f/0x150 [ 139.130954] path_setxattr+0x164/0x180 [ 139.133998] ? __pfx_path_setxattr+0x10/0x10 [ 139.137853] ? __pfx_ksys_pwrite64+0x10/0x10 [ 139.141299] ? debug_smp_processor_id+0x1b/0x30 [ 139.145714] ? fpregs_assert_state_consistent+0x6b/0x80 [ 139.150796] __x64_sys_setxattr+0x71/0x90 [ 139.155407] do_syscall_64+0x3f/0x90 [ 139.159035] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 139.163843] RIP: 0033:0x7f108cae4469 [ 139.166481] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 088 [ 139.183764] RSP: 002b:00007fff87588388 EFLAGS: 00000286 ORIG_RAX: 00000000000000bc [ 139.190657] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f108cae4469 [ 139.196586] RDX: 00007fff875883b0 RSI: 00007fff875883d1 RDI: 00007fff875883b6 [ 139.201716] RBP: 00007fff8758c530 R08: 0000000000000001 R09: 00007fff8758c618 [ 139.207940] R10: 0000000000000006 R11: 0000000000000286 R12: 00000000004004c0 [ 139.214007] R13: 00007fff8758c610 R14: 0000000000000000 R15: 0000000000000000 Signed-off-by: Edward Lo <loyuantsung@gmail.com> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
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Jul 10, 2023
vduse_vdpa_set_vq_affinity callback can be called with NULL value as cpu_mask when deleting the vduse device. This patch resets virtqueue's IRQ affinity mask value to set all CPUs instead of dereferencing NULL cpu_mask. [ 4760.952149] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 4760.959110] #PF: supervisor read access in kernel mode [ 4760.964247] #PF: error_code(0x0000) - not-present page [ 4760.969385] PGD 0 P4D 0 [ 4760.971927] Oops: 0000 [#1] PREEMPT SMP PTI [ 4760.976112] CPU: 13 PID: 2346 Comm: vdpa Not tainted 6.4.0-rc6+ #4 [ 4760.982291] Hardware name: Dell Inc. PowerEdge R640/0W23H8, BIOS 2.8.1 06/26/2020 [ 4760.989769] RIP: 0010:memcpy_orig+0xc5/0x130 [ 4760.994049] Code: 16 f8 4c 89 07 4c 89 4f 08 4c 89 54 17 f0 4c 89 5c 17 f8 c3 cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 fa 08 72 1b <4c> 8b 06 4c 8b 4c 16 f8 4c 89 07 4c 89 4c 17 f8 c3 cc cc cc cc 66 [ 4761.012793] RSP: 0018:ffffb1d565abb830 EFLAGS: 00010246 [ 4761.018020] RAX: ffff9f4bf6b27898 RBX: ffff9f4be23969c0 RCX: ffff9f4bcadf6400 [ 4761.025152] RDX: 0000000000000008 RSI: 0000000000000000 RDI: ffff9f4bf6b27898 [ 4761.032286] RBP: 0000000000000000 R08: 0000000000000008 R09: 0000000000000000 [ 4761.039416] R10: 0000000000000000 R11: 0000000000000600 R12: 0000000000000000 [ 4761.046549] R13: 0000000000000000 R14: 0000000000000080 R15: ffffb1d565abbb10 [ 4761.053680] FS: 00007f64c2ec2740(0000) GS:ffff9f635f980000(0000) knlGS:0000000000000000 [ 4761.061765] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4761.067513] CR2: 0000000000000000 CR3: 0000001875270006 CR4: 00000000007706e0 [ 4761.074645] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 4761.081775] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 4761.088909] PKRU: 55555554 [ 4761.091620] Call Trace: [ 4761.094074] <TASK> [ 4761.096180] ? __die+0x1f/0x70 [ 4761.099238] ? page_fault_oops+0x171/0x4f0 [ 4761.103340] ? exc_page_fault+0x7b/0x180 [ 4761.107265] ? asm_exc_page_fault+0x22/0x30 [ 4761.111460] ? memcpy_orig+0xc5/0x130 [ 4761.115126] vduse_vdpa_set_vq_affinity+0x3e/0x50 [vduse] [ 4761.120533] virtnet_clean_affinity.part.0+0x3d/0x90 [virtio_net] [ 4761.126635] remove_vq_common+0x1a4/0x250 [virtio_net] [ 4761.131781] virtnet_remove+0x5d/0x70 [virtio_net] [ 4761.136580] virtio_dev_remove+0x3a/0x90 [ 4761.140509] device_release_driver_internal+0x19b/0x200 [ 4761.145742] bus_remove_device+0xc2/0x130 [ 4761.149755] device_del+0x158/0x3e0 [ 4761.153245] ? kernfs_find_ns+0x35/0xc0 [ 4761.157086] device_unregister+0x13/0x60 [ 4761.161010] unregister_virtio_device+0x11/0x20 [ 4761.165543] device_release_driver_internal+0x19b/0x200 [ 4761.170770] bus_remove_device+0xc2/0x130 [ 4761.174782] device_del+0x158/0x3e0 [ 4761.178276] ? __pfx_vdpa_name_match+0x10/0x10 [vdpa] [ 4761.183336] device_unregister+0x13/0x60 [ 4761.187260] vdpa_nl_cmd_dev_del_set_doit+0x63/0xe0 [vdpa] Fixes: 28f6288 ("vduse: Support set_vq_affinity callback") Cc: xieyongji@bytedance.com Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> Message-Id: <20230622204851.318125-1-maxime.coquelin@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Xie Yongji <xieyongji@bytedance.com>
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When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 #15 [ffff88aa841efb88] device_del at ffffffff82179d23 #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff #20 [ffff88aa841eff10] kthread at ffffffff811d87a0 #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com> Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
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The following warning appears when using buffered events: [ 203.556451] WARNING: CPU: 53 PID: 10220 at kernel/trace/ring_buffer.c:3912 ring_buffer_discard_commit+0x2eb/0x420 [...] [ 203.670690] CPU: 53 PID: 10220 Comm: stress-ng-sysin Tainted: G E 6.7.0-rc2-default #4 56e6d0fcf5581e6e51eaaecbdaec2a2338c80f3a [ 203.670704] Hardware name: Intel Corp. GROVEPORT/GROVEPORT, BIOS GVPRCRB1.86B.0016.D04.1705030402 05/03/2017 [ 203.670709] RIP: 0010:ring_buffer_discard_commit+0x2eb/0x420 [ 203.735721] Code: 4c 8b 4a 50 48 8b 42 48 49 39 c1 0f 84 b3 00 00 00 49 83 e8 01 75 b1 48 8b 42 10 f0 ff 40 08 0f 0b e9 fc fe ff ff f0 ff 47 08 <0f> 0b e9 77 fd ff ff 48 8b 42 10 f0 ff 40 08 0f 0b e9 f5 fe ff ff [ 203.735734] RSP: 0018:ffffb4ae4f7b7d80 EFLAGS: 00010202 [ 203.735745] RAX: 0000000000000000 RBX: ffffb4ae4f7b7de0 RCX: ffff8ac10662c000 [ 203.735754] RDX: ffff8ac0c750be00 RSI: ffff8ac10662c000 RDI: ffff8ac0c004d400 [ 203.781832] RBP: ffff8ac0c039cea0 R08: 0000000000000000 R09: 0000000000000000 [ 203.781839] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 203.781842] R13: ffff8ac10662c000 R14: ffff8ac0c004d400 R15: ffff8ac10662c008 [ 203.781846] FS: 00007f4cd8a67740(0000) GS:ffff8ad798880000(0000) knlGS:0000000000000000 [ 203.781851] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 203.781855] CR2: 0000559766a74028 CR3: 00000001804c4000 CR4: 00000000001506f0 [ 203.781862] Call Trace: [ 203.781870] <TASK> [ 203.851949] trace_event_buffer_commit+0x1ea/0x250 [ 203.851967] trace_event_raw_event_sys_enter+0x83/0xe0 [ 203.851983] syscall_trace_enter.isra.0+0x182/0x1a0 [ 203.851990] do_syscall_64+0x3a/0xe0 [ 203.852075] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 203.852090] RIP: 0033:0x7f4cd870fa77 [ 203.982920] Code: 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 90 b8 89 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e9 43 0e 00 f7 d8 64 89 01 48 [ 203.982932] RSP: 002b:00007fff99717dd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000089 [ 203.982942] RAX: ffffffffffffffda RBX: 0000558ea1d7b6f0 RCX: 00007f4cd870fa77 [ 203.982948] RDX: 0000000000000000 RSI: 00007fff99717de0 RDI: 0000558ea1d7b6f0 [ 203.982957] RBP: 00007fff99717de0 R08: 00007fff997180e0 R09: 00007fff997180e0 [ 203.982962] R10: 00007fff997180e0 R11: 0000000000000246 R12: 00007fff99717f40 [ 204.049239] R13: 00007fff99718590 R14: 0000558e9f2127a8 R15: 00007fff997180b0 [ 204.049256] </TASK> For instance, it can be triggered by running these two commands in parallel: $ while true; do echo hist:key=id.syscall:val=hitcount > \ /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger; done $ stress-ng --sysinfo $(nproc) The warning indicates that the current ring_buffer_per_cpu is not in the committing state. It happens because the active ring_buffer_event doesn't actually come from the ring_buffer_per_cpu but is allocated from trace_buffered_event. The bug is in function trace_buffered_event_disable() where the following normally happens: * The code invokes disable_trace_buffered_event() via smp_call_function_many() and follows it by synchronize_rcu(). This increments the per-CPU variable trace_buffered_event_cnt on each target CPU and grants trace_buffered_event_disable() the exclusive access to the per-CPU variable trace_buffered_event. * Maintenance is performed on trace_buffered_event, all per-CPU event buffers get freed. * The code invokes enable_trace_buffered_event() via smp_call_function_many(). This decrements trace_buffered_event_cnt and releases the access to trace_buffered_event. A problem is that smp_call_function_many() runs a given function on all target CPUs except on the current one. The following can then occur: * Task X executing trace_buffered_event_disable() runs on CPU 0. * The control reaches synchronize_rcu() and the task gets rescheduled on another CPU 1. * The RCU synchronization finishes. At this point, trace_buffered_event_disable() has the exclusive access to all trace_buffered_event variables except trace_buffered_event[CPU0] because trace_buffered_event_cnt[CPU0] is never incremented and if the buffer is currently unused, remains set to 0. * A different task Y is scheduled on CPU 0 and hits a trace event. The code in trace_event_buffer_lock_reserve() sees that trace_buffered_event_cnt[CPU0] is set to 0 and decides the use the buffer provided by trace_buffered_event[CPU0]. * Task X continues its execution in trace_buffered_event_disable(). The code incorrectly frees the event buffer pointed by trace_buffered_event[CPU0] and resets the variable to NULL. * Task Y writes event data to the now freed buffer and later detects the created inconsistency. The issue is observable since commit dea4997 ("tracing: Fix warning in trace_buffered_event_disable()") which moved the call of trace_buffered_event_disable() in __ftrace_event_enable_disable() earlier, prior to invoking call->class->reg(.. TRACE_REG_UNREGISTER ..). The underlying problem in trace_buffered_event_disable() is however present since the original implementation in commit 0fc1b09 ("tracing: Use temp buffer when filtering events"). Fix the problem by replacing the two smp_call_function_many() calls with on_each_cpu_mask() which invokes a given callback on all CPUs. Link: https://lore.kernel.org/all/20231127151248.7232-2-petr.pavlu@suse.com/ Link: https://lkml.kernel.org/r/20231205161736.19663-2-petr.pavlu@suse.com Cc: stable@vger.kernel.org Fixes: 0fc1b09 ("tracing: Use temp buffer when filtering events") Fixes: dea4997 ("tracing: Fix warning in trace_buffered_event_disable()") Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
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When working on LED support for r8169 I got the following lockdep warning. Easiest way to prevent this scenario seems to be to take the RTNL lock before the trigger_data lock in set_device_name(). ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc2-next-20231124+ #2 Not tainted ------------------------------------------------------ bash/383 is trying to acquire lock: ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev] but task is already holding lock: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 rtnl_lock+0x12/0x20 set_device_name+0xa9/0x120 [ledtrig_netdev] netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 -> #0 (&trigger_data->lock){+.+.}-{3:3}: __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&trigger_data->lock); lock(rtnl_mutex); lock(&trigger_data->lock); *** DEADLOCK *** 8 locks held by bash/383: #0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0 #1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210 #2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210 #3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140 #4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140 #5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140 #6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120 #7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 stack backtrace: CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2 Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023 Call Trace: <TASK> dump_stack_lvl+0x5c/0xd0 dump_stack+0x10/0x20 print_circular_bug+0x2dd/0x410 check_noncircular+0x131/0x150 __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] __mutex_lock+0x9b/0xb50 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __this_cpu_preempt_check+0x13/0x20 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __cancel_work_timer+0x11c/0x1b0 ? __mutex_lock+0x123/0xb50 mutex_lock_nested+0x16/0x20 ? mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 ? preempt_count_add+0x49/0xc0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 RIP: 0033:0x7f269055d034 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48 RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034 RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001 RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000 </TASK> Fixes: d5e0126 ("leds: trigger: netdev: add additional specific link speed mode") Cc: stable@vger.kernel.org Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Lee Jones <lee@kernel.org> Link: https://lore.kernel.org/r/fb5c8294-2a10-4bf5-8f10-3d2b77d2757e@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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The qcom_pcie_enable_aspm() helper is called from pci_walk_bus() during host init to enable ASPM. Since pci_walk_bus() already holds a pci_bus_sem read lock, use pci_enable_link_state_locked() to enable link states in order to avoid a potential deadlock (e.g. in case someone takes a write lock before reacquiring the read lock). This issue was reported by lockdep: ============================================ WARNING: possible recursive locking detected 6.7.0-rc1 #4 Not tainted -------------------------------------------- kworker/u16:6/147 is trying to acquire lock: ffffbf3ff9d2cfa0 (pci_bus_sem){++++}-{3:3}, at: pci_enable_link_state+0x74/0x1e8 but task is already holding lock: ffffbf3ff9d2cfa0 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(pci_bus_sem); lock(pci_bus_sem); *** DEADLOCK *** Fixes: 9f4f3df ("PCI: qcom: Enable ASPM for platforms supporting 1.9.0 ops") Link: https://lore.kernel.org/r/20231128081512.19387-4-johan+linaro@kernel.org Signed-off-by: Johan Hovold <johan+linaro@kernel.org> [bhelgaas: add "potential" in subject since the deadlock has only been reported by lockdep, include helper name in commit log] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
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Dec 23, 2023
Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep warning: ============================================ WARNING: possible recursive locking detected 6.7.0-rc5-wt+ torvalds#532 Not tainted -------------------------------------------- sh/92 is trying to acquire lock: c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 but task is already holding lock: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&irq_desc_lock_class); lock(&irq_desc_lock_class); *** DEADLOCK *** May be due to missing lock nesting notation 6 locks held by sh/92: #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178 #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284 #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284 #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8 #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100 stack backtrace: CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ torvalds#532 Hardware name: Atmel SAMA5 unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x34/0x48 dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c __lock_acquire from lock_acquire.part.0+0x124/0x2d0 lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78 _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100 __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204 irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4 atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204 irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8 gpio_keys_suspend from dpm_run_callback+0xe4/0x248 dpm_run_callback from __device_suspend+0x234/0x91c __device_suspend from dpm_suspend+0x224/0x43c dpm_suspend from dpm_suspend_start+0x9c/0xa8 dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84 suspend_devices_and_enter from pm_suspend+0x460/0x4e8 pm_suspend from state_store+0x78/0xe4 state_store from kernfs_fop_write_iter+0x1a0/0x284 kernfs_fop_write_iter from vfs_write+0x38c/0x6f4 vfs_write from ksys_write+0xd8/0x178 ksys_write from ret_fast_syscall+0x0/0x1c Exception stack(0xc52b3fa8 to 0xc52b3ff0) 3fa0: 00000004 005a0ae8 00000001 005a0ae8 00000004 00000001 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190 3fe0: 00000004 b6c61678 aec5a041 aebf1a26 This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever a wake up source configures an IRQ through irq_set_irq_wake, it will lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent" IRQ which will do the same on its own IRQ desc, but since those two locks share the same class, lockdep reports this as an issue. Fix lockdep false positive by setting a different class for parent and children IRQ Fixes: 7761808 ("pinctrl: introduce driver for Atmel PIO4 controller") Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com> Link: https://lore.kernel.org/r/20231215-lockdep_warning-v1-1-8137b2510ed5@bootlin.com Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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… place apply_alternatives() treats alternatives with the ALT_FLAG_NOT flag set special as it optimizes the existing NOPs in place. Unfortunately, this happens with interrupts enabled and does not provide any form of core synchronization. So an interrupt hitting in the middle of the update and using the affected code path will observe a half updated NOP and crash and burn. The following 3 NOP sequence was observed to expose this crash halfway reliably under QEMU 32bit: 0x90 0x90 0x90 which is replaced by the optimized 3 byte NOP: 0x8d 0x76 0x00 So an interrupt can observe: 1) 0x90 0x90 0x90 nop nop nop 2) 0x8d 0x90 0x90 undefined 3) 0x8d 0x76 0x90 lea -0x70(%esi),%esi 4) 0x8d 0x76 0x00 lea 0x0(%esi),%esi Where only #1 and #4 are true NOPs. The same problem exists for 64bit obviously. Disable interrupts around this NOP optimization and invoke sync_core() before re-enabling them. Fixes: 270a69c ("x86/alternative: Support relocations in alternatives") Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/ZT6narvE%2BLxX%2B7Be@windriver.com
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Andrii Nakryiko says: ==================== Tighten up arg:ctx type enforcement Follow up fixes for kernel-side and libbpf-side logic around handling arg:ctx (__arg_ctx) tagged arguments of BPF global subprogs. Patch #1 adds libbpf feature detection of kernel-side __arg_ctx support to avoid unnecessary rewriting BTF types. With stricter kernel-side type enforcement this is now mandatory to avoid problems with using `struct bpf_user_pt_regs_t` instead of actual typedef. For __arg_ctx tagged arguments verifier is now supporting either `bpf_user_pt_regs_t` typedef or resolves it down to the actual struct (pt_regs/user_pt_regs/user_regs_struct), depending on architecture), but for old kernels without __arg_ctx support it's more backwards compatible for libbpf to use `struct bpf_user_pt_regs_t` rewrite which will work on wider range of kernels. So feature detection prevent libbpf accidentally breaking global subprogs on new kernels. We also adjust selftests to do similar feature detection (much simpler, but potentially breaking due to kernel source code refactoring, which is fine for selftests), and skip tests expecting libbpf's BTF type rewrites. Patch #2 is preparatory refactoring for patch #3 which adds type enforcement for arg:ctx tagged global subprog args. See the patch for specifics. Patch #4 adds many new cases to ensure type logic works as expected. Finally, patch #5 adds a relevant subset of kernel-side type checks to __arg_ctx cases that libbpf supports rewrite of. In libbpf's case, type violations are reported as warnings and BTF rewrite is not performed, which will eventually lead to BPF verifier complaining at program verification time. Good care was taken to avoid conflicts between bpf and bpf-next tree (which has few follow up refactorings in the same code area). Once trees converge some of the code will be moved around a bit (and some will be deleted), but with no change to functionality or general shape of the code. v2->v3: - support `bpf_user_pt_regs_t` typedef for KPROBE and PERF_EVENT (CI); v1->v2: - add user_pt_regs and user_regs_struct support for PERF_EVENT (CI); - drop FEAT_ARG_CTX_TAG enum leftover from patch #1; - fix warning about default: without break in the switch (CI). ==================== Link: https://lore.kernel.org/r/20240118033143.3384355-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Petr Machata says: ==================== mlxsw: Miscellaneous fixes This patchset is a bric-a-brac of fixes for bugs impacting mlxsw. - Patches #1 and #2 fix issues in ACL handling error paths. - Patch #3 fixes stack corruption in ACL code that a recent FW update has uncovered. - Patch #4 fixes an issue in handling of IPIP next hops. - Patch #5 fixes a typo in a the qos_pfc selftest - Patch #6 fixes the same selftest to work with 8-lane ports. ==================== Link: https://lore.kernel.org/r/cover.1705502064.git.petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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There is this reported crash when experimenting with the lvm2 testsuite. The list corruption is caused by the fact that the postsuspend and resume methods were not paired correctly; there were two consecutive calls to the origin_postsuspend function. The second call attempts to remove the "hash_list" entry from a list, while it was already removed by the first call. Fix __dm_internal_resume so that it calls the preresume and resume methods of the table's targets. If a preresume method of some target fails, we are in a tricky situation. We can't return an error because dm_internal_resume isn't supposed to return errors. We can't return success, because then the "resume" and "postsuspend" methods would not be paired correctly. So, we set the DMF_SUSPENDED flag and we fake normal suspend - it may confuse userspace tools, but it won't cause a kernel crash. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:56! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 1 PID: 8343 Comm: dmsetup Not tainted 6.8.0-rc6 #4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 RIP: 0010:__list_del_entry_valid_or_report+0x77/0xc0 <snip> RSP: 0018:ffff8881b831bcc0 EFLAGS: 00010282 RAX: 000000000000004e RBX: ffff888143b6eb80 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff819053d0 RDI: 00000000ffffffff RBP: ffff8881b83a3400 R08: 00000000fffeffff R09: 0000000000000058 R10: 0000000000000000 R11: ffffffff81a24080 R12: 0000000000000001 R13: ffff88814538e000 R14: ffff888143bc6dc0 R15: ffffffffa02e4bb0 FS: 00000000f7c0f780(0000) GS:ffff8893f0a40000(0000) knlGS:0000000000000000 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000057fb5000 CR3: 0000000143474000 CR4: 00000000000006b0 Call Trace: <TASK> ? die+0x2d/0x80 ? do_trap+0xeb/0xf0 ? __list_del_entry_valid_or_report+0x77/0xc0 ? do_error_trap+0x60/0x80 ? __list_del_entry_valid_or_report+0x77/0xc0 ? exc_invalid_op+0x49/0x60 ? __list_del_entry_valid_or_report+0x77/0xc0 ? asm_exc_invalid_op+0x16/0x20 ? table_deps+0x1b0/0x1b0 [dm_mod] ? __list_del_entry_valid_or_report+0x77/0xc0 origin_postsuspend+0x1a/0x50 [dm_snapshot] dm_table_postsuspend_targets+0x34/0x50 [dm_mod] dm_suspend+0xd8/0xf0 [dm_mod] dev_suspend+0x1f2/0x2f0 [dm_mod] ? table_deps+0x1b0/0x1b0 [dm_mod] ctl_ioctl+0x300/0x5f0 [dm_mod] dm_compat_ctl_ioctl+0x7/0x10 [dm_mod] __x64_compat_sys_ioctl+0x104/0x170 do_syscall_64+0x184/0x1b0 entry_SYSCALL_64_after_hwframe+0x46/0x4e RIP: 0033:0xf7e6aead <snip> ---[ end trace 0000000000000000 ]--- Fixes: ffcc393 ("dm: enhance internal suspend and resume interface") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
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…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 unlike early commit path stage which triggers a call to abort, an explicit release of the batch is required on abort, otherwise mutex is released and commit_list remains in place. Patch #2 release mutex after nft_gc_seq_end() in commit path, otherwise async GC worker could collect expired objects. Patch #3 flush pending destroy work in module removal path, otherwise UaF is possible. Patch #4 and #6 restrict the table dormant flag with basechain updates to fix state inconsistency in the hook registration. Patch #5 adds missing RCU read side lock to flowtable type to avoid races with module removal. * tag 'nf-24-04-04' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nf_tables: discard table flag update with pending basechain deletion netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get() netfilter: nf_tables: reject new basechain after table flag update netfilter: nf_tables: flush pending destroy work before exit_net release netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path netfilter: nf_tables: release batch on table validation from abort path ==================== Link: https://lore.kernel.org/r/20240404104334.1627-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Drop support for virtualizing adaptive PEBS, as KVM's implementation is architecturally broken without an obvious/easy path forward, and because exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak host kernel addresses to the guest. Bug #1 is that KVM doesn't account for the upper 32 bits of IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters() stores local variables as u8s and truncates the upper bits too, etc. Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value for PEBS events, perf will _always_ generate an adaptive record, even if the guest requested a basic record. Note, KVM will also enable adaptive PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero, i.e. the guest will only ever see Basic records. Bug #3 is in perf. intel_pmu_disable_fixed() doesn't clear the upper bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE either. I.e. perf _always_ enables ADAPTIVE counters, regardless of what KVM requests. Bug #4 is that adaptive PEBS *might* effectively bypass event filters set by the host, as "Updated Memory Access Info Group" records information that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER. Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least zeros) when entering a vCPU with adaptive PEBS, which allows the guest to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries" records. Disable adaptive PEBS support as an immediate fix due to the severity of the LBR leak in particular, and because fixing all of the bugs will be non-trivial, e.g. not suitable for backporting to stable kernels. Note! This will break live migration, but trying to make KVM play nice with live migration would be quite complicated, wouldn't be guaranteed to work (i.e. KVM might still kill/confuse the guest), and it's not clear that there are any publicly available VMMs that support adaptive PEBS, let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't support PEBS in any capacity. Link: https://lore.kernel.org/all/20240306230153.786365-1-seanjc@google.com Link: https://lore.kernel.org/all/ZeepGjHCeSfadANM@google.com Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS") Cc: stable@vger.kernel.org Cc: Like Xu <like.xu.linux@gmail.com> Cc: Mingwei Zhang <mizhang@google.com> Cc: Zhenyu Wang <zhenyuw@linux.intel.com> Cc: Zhang Xiong <xiong.y.zhang@intel.com> Cc: Lv Zhiyuan <zhiyuan.lv@intel.com> Cc: Dapeng Mi <dapeng1.mi@intel.com> Cc: Jim Mattson <jmattson@google.com> Acked-by: Like Xu <likexu@tencent.com> Link: https://lore.kernel.org/r/20240307005833.827147-1-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
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…git/netfilter/nf netfilter pull request 24-04-11 Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patches #1 and #2 add missing rcu read side lock when iterating over expression and object type list which could race with module removal. Patch #3 prevents promisc packet from visiting the bridge/input hook to amend a recent fix to address conntrack confirmation race in br_netfilter and nf_conntrack_bridge. Patch #4 adds and uses iterate decorator type to fetch the current pipapo set backend datastructure view when netlink dumps the set elements. Patch #5 fixes removal of duplicate elements in the pipapo set backend. Patch #6 flowtable validates pppoe header before accessing it. Patch #7 fixes flowtable datapath for pppoe packets, otherwise lookup fails and pppoe packets follow classic path. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
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When I did hard offline test with hugetlb pages, below deadlock occurs: ====================================================== WARNING: possible circular locking dependency detected 6.8.0-11409-gf6cef5f8c37f #1 Not tainted ------------------------------------------------------ bash/46904 is trying to acquire lock: ffffffffabe68910 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_slow_dec+0x16/0x60 but task is already holding lock: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (pcp_batch_high_lock){+.+.}-{3:3}: __mutex_lock+0x6c/0x770 page_alloc_cpu_online+0x3c/0x70 cpuhp_invoke_callback+0x397/0x5f0 __cpuhp_invoke_callback_range+0x71/0xe0 _cpu_up+0xeb/0x210 cpu_up+0x91/0xe0 cpuhp_bringup_mask+0x49/0xb0 bringup_nonboot_cpus+0xb7/0xe0 smp_init+0x25/0xa0 kernel_init_freeable+0x15f/0x3e0 kernel_init+0x15/0x1b0 ret_from_fork+0x2f/0x50 ret_from_fork_asm+0x1a/0x30 -> #0 (cpu_hotplug_lock){++++}-{0:0}: __lock_acquire+0x1298/0x1cd0 lock_acquire+0xc0/0x2b0 cpus_read_lock+0x2a/0xc0 static_key_slow_dec+0x16/0x60 __hugetlb_vmemmap_restore_folio+0x1b9/0x200 dissolve_free_huge_page+0x211/0x260 __page_handle_poison+0x45/0xc0 memory_failure+0x65e/0xc70 hard_offline_page_store+0x55/0xa0 kernfs_fop_write_iter+0x12c/0x1d0 vfs_write+0x387/0x550 ksys_write+0x64/0xe0 do_syscall_64+0xca/0x1e0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pcp_batch_high_lock); lock(cpu_hotplug_lock); lock(pcp_batch_high_lock); rlock(cpu_hotplug_lock); *** DEADLOCK *** 5 locks held by bash/46904: #0: ffff98f6c3bb23f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0 #1: ffff98f6c328e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0 #2: ffff98ef83b31890 (kn->active#113){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0 #3: ffffffffabf9db48 (mf_mutex){+.+.}-{3:3}, at: memory_failure+0x44/0xc70 #4: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40 stack backtrace: CPU: 10 PID: 46904 Comm: bash Kdump: loaded Not tainted 6.8.0-11409-gf6cef5f8c37f #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x68/0xa0 check_noncircular+0x129/0x140 __lock_acquire+0x1298/0x1cd0 lock_acquire+0xc0/0x2b0 cpus_read_lock+0x2a/0xc0 static_key_slow_dec+0x16/0x60 __hugetlb_vmemmap_restore_folio+0x1b9/0x200 dissolve_free_huge_page+0x211/0x260 __page_handle_poison+0x45/0xc0 memory_failure+0x65e/0xc70 hard_offline_page_store+0x55/0xa0 kernfs_fop_write_iter+0x12c/0x1d0 vfs_write+0x387/0x550 ksys_write+0x64/0xe0 do_syscall_64+0xca/0x1e0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7fc862314887 Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 RSP: 002b:00007fff19311268 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007fc862314887 RDX: 000000000000000c RSI: 000056405645fe10 RDI: 0000000000000001 RBP: 000056405645fe10 R08: 00007fc8623d1460 R09: 000000007fffffff R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c R13: 00007fc86241b780 R14: 00007fc862417600 R15: 00007fc862416a00 In short, below scene breaks the lock dependency chain: memory_failure __page_handle_poison zone_pcp_disable -- lock(pcp_batch_high_lock) dissolve_free_huge_page __hugetlb_vmemmap_restore_folio static_key_slow_dec cpus_read_lock -- rlock(cpu_hotplug_lock) Fix this by calling drain_all_pages() instead. This issue won't occur until commit a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key"). As it introduced rlock(cpu_hotplug_lock) in dissolve_free_huge_page() code path while lock(pcp_batch_high_lock) is already in the __page_handle_poison(). [linmiaohe@huawei.com: extend comment per Oscar] [akpm@linux-foundation.org: reflow block comment] Link: https://lkml.kernel.org/r/20240407085456.2798193-1-linmiaohe@huawei.com Fixes: a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Oscar Salvador <osalvador@suse.de> Reviewed-by: Jane Chu <jane.chu@oracle.com> Cc: Naoya Horiguchi <nao.horiguchi@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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vhost_worker will call tun call backs to receive packets. If too many illegal packets arrives, tun_do_read will keep dumping packet contents. When console is enabled, it will costs much more cpu time to dump packet and soft lockup will be detected. net_ratelimit mechanism can be used to limit the dumping rate. PID: 33036 TASK: ffff949da6f20000 CPU: 23 COMMAND: "vhost-32980" #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e #3 [fffffe00003fced0] do_nmi at ffffffff8922660d #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663 [exception RIP: io_serial_in+20] RIP: ffffffff89792594 RSP: ffffa655314979e8 RFLAGS: 00000002 RAX: ffffffff89792500 RBX: ffffffff8af428a0 RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff8af428a0 RBP: 0000000000002710 R8: 0000000000000004 R9: 000000000000000f R10: 0000000000000000 R11: ffffffff8acbf64f R12: 0000000000000020 R13: ffffffff8acbf698 R14: 0000000000000058 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07 #12 [ffffa65531497b68] printk at ffffffff89318306 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun] #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun] #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net] #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost] #18 [ffffa65531497f10] kthread at ffffffff892d2e72 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors") Signed-off-by: Lei Chen <lei.chen@smartx.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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…rnel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: Patch #1 skips transaction if object type provides no .update interface. Patch #2 skips NETDEV_CHANGENAME which is unused. Patch #3 enables conntrack to handle Multicast Router Advertisements and Multicast Router Solicitations from the Multicast Router Discovery protocol (RFC4286) as untracked opposed to invalid packets. From Linus Luessing. Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of dropping them, from Jason Xing. Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0, also from Jason. Patch #6 removes reference in netfilter's sysctl documentation on pickup entries which were already removed by Florian Westphal. Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which allows to evict entries from the conntrack table, also from Florian. Patches #8 to #16 updates nf_tables pipapo set backend to allocate the datastructure copy on-demand from preparation phase, to better deal with OOM situations where .commit step is too late to fail. Series from Florian Westphal. Patch #17 adds a selftest with packetdrill to cover conntrack TCP state transitions, also from Florian. Patch #18 use GFP_KERNEL to clone elements from control plane to avoid quick atomic reserves exhaustion with large sets, reporter refers to million entries magnitude. * tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: netfilter: nf_tables: allow clone callbacks to sleep selftests: netfilter: add packetdrill based conntrack tests netfilter: nft_set_pipapo: remove dirty flag netfilter: nft_set_pipapo: move cloning of match info to insert/removal path netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone netfilter: nft_set_pipapo: merge deactivate helper into caller netfilter: nft_set_pipapo: prepare walk function for on-demand clone netfilter: nft_set_pipapo: prepare destroy function for on-demand clone netfilter: nft_set_pipapo: make pipapo_clone helper return NULL netfilter: nft_set_pipapo: move prove_locking helper around netfilter: conntrack: remove flowtable early-drop test netfilter: conntrack: documentation: remove reference to non-existent sysctl netfilter: use NF_DROP instead of -NF_DROP netfilter: conntrack: dccp: try not to drop skb in conntrack netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler netfilter: nf_tables: skip transaction if update object is not implemented ==================== Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Bos can be put with multiple unrelated dma-resv locks held. But imported bos attempt to grab the bo dma-resv during dma-buf detach that typically happens during cleanup. That leads to lockde splats similar to the below and a potential ABBA deadlock. Fix this by always taking the delayed workqueue cleanup path for imported bos. Requesting stable fixes from when the Xe driver was introduced, since its usage of drm_exec and wide vm dma_resvs appear to be the first reliable trigger of this. [22982.116427] ============================================ [22982.116428] WARNING: possible recursive locking detected [22982.116429] 6.10.0-rc2+ #10 Tainted: G U W [22982.116430] -------------------------------------------- [22982.116430] glxgears:sh0/5785 is trying to acquire lock: [22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0 [22982.116438] but task is already holding lock: [22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116442] other info that might help us debug this: [22982.116442] Possible unsafe locking scenario: [22982.116443] CPU0 [22982.116444] ---- [22982.116444] lock(reservation_ww_class_mutex); [22982.116445] lock(reservation_ww_class_mutex); [22982.116447] *** DEADLOCK *** [22982.116447] May be due to missing lock nesting notation [22982.116448] 5 locks held by glxgears:sh0/5785: [22982.116449] #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe] [22982.116507] #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe] [22982.116578] #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe] [22982.116647] #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe] [22982.116716] #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116719] stack backtrace: [22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G U W 6.10.0-rc2+ #10 [22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [22982.116723] Call Trace: [22982.116724] <TASK> [22982.116725] dump_stack_lvl+0x77/0xb0 [22982.116727] __lock_acquire+0x1232/0x2160 [22982.116730] lock_acquire+0xcb/0x2d0 [22982.116732] ? dma_buf_detach+0x3b/0xf0 [22982.116734] ? __lock_acquire+0x417/0x2160 [22982.116736] __ww_mutex_lock.constprop.0+0xd0/0x13b0 [22982.116738] ? dma_buf_detach+0x3b/0xf0 [22982.116741] ? dma_buf_detach+0x3b/0xf0 [22982.116743] ? ww_mutex_lock+0x2b/0x90 [22982.116745] ww_mutex_lock+0x2b/0x90 [22982.116747] dma_buf_detach+0x3b/0xf0 [22982.116749] drm_prime_gem_destroy+0x2f/0x40 [drm] [22982.116775] xe_ttm_bo_destroy+0x32/0x220 [xe] [22982.116818] ? __mutex_unlock_slowpath+0x3a/0x290 [22982.116821] drm_exec_unlock_all+0xa1/0xd0 [drm_exec] [22982.116823] drm_exec_fini+0x12/0xb0 [drm_exec] [22982.116824] xe_validation_ctx_fini+0x15/0x40 [xe] [22982.116892] xe_vma_destroy_unlocked+0xb1/0xe0 [xe] [22982.116959] xe_vm_close_and_put+0x41a/0x9b0 [xe] [22982.117025] ? xa_find+0xe3/0x1e0 [22982.117028] xe_file_close+0x10a/0x1c0 [xe] [22982.117074] drm_file_free+0x22a/0x280 [drm] [22982.117099] drm_release_noglobal+0x22/0x70 [drm] [22982.117119] __fput+0xf1/0x2d0 [22982.117122] task_work_run+0x59/0x90 [22982.117125] do_exit+0x330/0xb40 [22982.117127] do_group_exit+0x36/0xa0 [22982.117129] get_signal+0xbd2/0xbe0 [22982.117131] arch_do_signal_or_restart+0x3e/0x240 [22982.117134] syscall_exit_to_user_mode+0x1e7/0x290 [22982.117137] do_syscall_64+0xa1/0x180 [22982.117139] ? lock_acquire+0xcb/0x2d0 [22982.117140] ? __set_task_comm+0x28/0x1e0 [22982.117141] ? find_held_lock+0x2b/0x80 [22982.117144] ? __set_task_comm+0xe1/0x1e0 [22982.117145] ? lock_release+0xca/0x290 [22982.117147] ? __do_sys_prctl+0x245/0xab0 [22982.117149] ? lockdep_hardirqs_on_prepare+0xde/0x190 [22982.117150] ? syscall_exit_to_user_mode+0xb0/0x290 [22982.117152] ? do_syscall_64+0xa1/0x180 [22982.117154] ? __lock_acquire+0x417/0x2160 [22982.117155] ? reacquire_held_locks+0xd1/0x1f0 [22982.117156] ? do_user_addr_fault+0x30c/0x790 [22982.117158] ? lock_acquire+0xcb/0x2d0 [22982.117160] ? find_held_lock+0x2b/0x80 [22982.117162] ? do_user_addr_fault+0x357/0x790 [22982.117163] ? lock_release+0xca/0x290 [22982.117164] ? do_user_addr_fault+0x361/0x790 [22982.117166] ? trace_hardirqs_off+0x4b/0xc0 [22982.117168] ? clear_bhb_loop+0x45/0xa0 [22982.117170] ? clear_bhb_loop+0x45/0xa0 [22982.117172] ? clear_bhb_loop+0x45/0xa0 [22982.117174] entry_SYSCALL_64_after_hwframe+0x76/0x7e [22982.117176] RIP: 0033:0x7f943d267169 [22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f. [22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169 [22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0 [22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff [22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0 [22982.117202] </TASK> Fixes: dd08ebf ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Christian König <christian.koenig@amd.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: dri-devel@lists.freedesktop.org Cc: intel-xe@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v6.8+ Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Reviewed-by: Matthew Brost <matthew.brost@intel.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240628153848.4989-1-thomas.hellstrom@linux.intel.com
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…rnel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: Patch #1 adds ctnetlink support for kernel side filtering for deletions, from Changliang Wu. Patch #2 updates nft_counter support to Use u64_stats_t, from Sebastian Andrzej Siewior. Patch #3 uses kmemdup_array() in all xtables frontends, from Yan Zhen. Patch #4 is a oneliner to use ERR_CAST() in nf_conntrack instead opencoded casting, from Shen Lichuan. Patch #5 removes unused argument in nftables .validate interface, from Florian Westphal. Patch #6 is a oneliner to correct a typo in nftables kdoc, from Simon Horman. Patch #7 fixes missing kdoc in nftables, also from Simon. Patch #8 updates nftables to handle timeout less than CONFIG_HZ. Patch #9 rejects element expiration if timeout is zero, otherwise it is silently ignored. Patch #10 disallows element expiration larger than timeout. Patch #11 removes unnecessary READ_ONCE annotation while mutex is held. Patch #12 adds missing READ_ONCE/WRITE_ONCE annotation in dynset. Patch #13 annotates data-races around element expiration. Patch #14 allocates timeout and expiration in one single set element extension, they are tighly couple, no reason to keep them separated anymore. Patch #15 updates nftables to interpret zero timeout element as never times out. Note that it is already possible to declare sets with elements that never time out but this generalizes to all kind of set with timeouts. Patch #16 supports for element timeout and expiration updates. * tag 'nf-next-24-09-06' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: netfilter: nf_tables: set element timeout update support netfilter: nf_tables: zero timeout means element never times out netfilter: nf_tables: consolidate timeout extension for elements netfilter: nf_tables: annotate data-races around element expiration netfilter: nft_dynset: annotate data-races around set timeout netfilter: nf_tables: remove annotation to access set timeout while holding lock netfilter: nf_tables: reject expiration higher than timeout netfilter: nf_tables: reject element expiration with no timeout netfilter: nf_tables: elements with timeout below CONFIG_HZ never expire netfilter: nf_tables: Add missing Kernel doc netfilter: nf_tables: Correct spelling in nf_tables.h netfilter: nf_tables: drop unused 3rd argument from validate callback ops netfilter: conntrack: Convert to use ERR_CAST() netfilter: Use kmemdup_array instead of kmemdup for multiple allocation netfilter: nft_counter: Use u64_stats_t for statistic. netfilter: ctnetlink: support CTA_FILTER for flush ==================== Link: https://patch.msgid.link/20240905232920.5481-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Daniel Machon says: ==================== net: lan966x: use the newly introduced FDMA library This patch series is the second of a 2-part series [1], that adds a new common FDMA library for Microchip switch chips Sparx5 and lan966x. These chips share the same FDMA engine, and as such will benefit from a common library with a common implementation. This also has the benefit of removing a lot of open-coded bookkeeping and duplicate code for the two drivers. In this second series, the FDMA library will be taken into use by the lan966x switch driver. ################### # Example of use: # ################### - Initialize the rx and tx fdma structs with values for: number of DCB's, number of DB's, channel ID, DB size (data buffer size), and total size of the requested memory. Also provide two callbacks: nextptr_cb() and dataptr_cb() for getting the nextptr and dataptr. - Allocate memory using fdma_alloc_phys() or fdma_alloc_coherent(). - Initialize the DCB's with fdma_dcb_init(). - Add new DCB's with fdma_dcb_add(). - Free memory with fdma_free_phys() or fdma_free_coherent(). ##################### # Patch breakdown: # ##################### Patch #1: select FDMA library for lan966x. Patch #2: includes the fdma_api.h header and removes old symbols. Patch #3: replaces old rx and tx variables with equivalent ones from the fdma struct. Only the variables that can be changed without breaking traffic is changed in this patch. Patch #4: uses the library for allocation of rx buffers. This requires quite a bit of refactoring in this single patch. Patch #5: uses the library for adding DCB's in the rx path. Patch #6: uses the library for freeing rx buffers. Patch #7: uses the library for allocation of tx buffers. This requires quite a bit of refactoring in this single patch. Patch #8: uses the library for adding DCB's in the tx path. Patch #9: uses the library helpers in the tx path. Patch #10: ditch last_in_use variable and use library instead. Patch #11: uses library helpers throughout. Patch #12: refactor lan966x_fdma_reload() function. [1] https://lore.kernel.org/netdev/20240902-fdma-sparx5-v1-0-1e7d5e5a9f34@microchip.com/ Signed-off-by: Daniel Machon <daniel.machon@microchip.com> ==================== Link: https://patch.msgid.link/20240905-fdma-lan966x-v1-0-e083f8620165@microchip.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Ido Schimmel says: ==================== net: fib_rules: Add DSCP selector support Currently, the kernel rejects IPv4 FIB rules that try to match on the upper three DSCP bits: # ip -4 rule add tos 0x1c table 100 # ip -4 rule add tos 0x3c table 100 Error: Invalid tos. The reason for that is that historically users of the FIB lookup API only populated the lower three DSCP bits in the TOS field of the IPv4 flow key ('flowi4_tos'), which fits the TOS definition from the initial IPv4 specification (RFC 791). This is not very useful nowadays and instead some users want to be able to match on the six bits DSCP field, which replaced the TOS and IP precedence fields over 25 years ago (RFC 2474). In addition, the current behavior differs between IPv4 and IPv6 which does allow users to match on the entire DSCP field using the TOS selector. Recent patchsets made sure that callers of the FIB lookup API now populate the entire DSCP field in the IPv4 flow key. Therefore, it is now possible to extend FIB rules to match on DSCP. This is done by adding a new DSCP attribute which is implemented for both IPv4 and IPv6 to provide user space programs a consistent behavior between both address families. The behavior of the old TOS selector is unchanged and IPv4 FIB rules using it will only match on the lower three DSCP bits. The kernel will reject rules that try to use both selectors. Patch #1 adds the new DSCP attribute but rejects its usage. Patches #2-#3 implement IPv4 and IPv6 support. Patch #4 allows user space to use the new attribute. Patches #5-#6 add selftests. ==================== Link: https://patch.msgid.link/20240911093748.3662015-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Nelson Escobar says: ==================== enic: Report per queue stats Patch #1: Use a macro instead of static const variables for array sizes. I didn't want to add more static const variables in the next patch so clean up the existing ones first. Patch #2: Collect per queue statistics Patch #3: Report per queue stats in netdev qstats Patch #4: Report some per queue stats in ethtool # NETIF="eno6" tools/testing/selftests/drivers/net/stats.py KTAP version 1 1..5 ok 1 stats.check_pause # XFAIL pause not supported by the device ok 2 stats.check_fec # XFAIL FEC not supported by the device ok 3 stats.pkt_byte_sum ok 4 stats.qstat_by_ifindex ok 5 stats.check_down # tools/net/ynl/cli.py --spec Documentation/netlink/specs/netdev.yaml \ --dump qstats-get --json '{"ifindex": "34"}' [{'ifindex': 34, 'rx-bytes': 66762680, 'rx-csum-unnecessary': 1009345, 'rx-hw-drop-overruns': 0, 'rx-hw-drops': 0, 'rx-packets': 1009673, 'tx-bytes': 137936674899, 'tx-csum-none': 125, 'tx-hw-gso-packets': 2408712, 'tx-needs-csum': 2431531, 'tx-packets': 15475466, 'tx-stop': 0, 'tx-wake': 0}] v2: https://lore.kernel.org/20240905010900.24152-1-neescoba@cisco.com v1: https://lore.kernel.org/20240823235401.29996-1-neescoba@cisco.com ==================== Link: https://patch.msgid.link/20240912005039.10797-1-neescoba@cisco.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Should have done this issue first since its what kicked the whole thing off. When using 9p, the synchronous nature of protocol operations makes things quite unbearable on connections with any sort of latency and can even limit effective bandwidth via readahead. I think this ultimately motivated recent increases in msize (which has other advantages).
Regardless, underlying problem is no sensible caching options (existing options are somewhat fragile and inconsistent). So, first class problem to solve is enable readahead ideally without the fragility of other caching modes.
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