integrated assembler does not support variable assignment #19

nickdesaulniers · 2018-05-11T20:11:33Z

example:

➜  kernel-all git:(master) ✗ cat test.S 
var_xdata = %rcx

xorq var_xdata, var_xdata
➜  kernel-all git:(master) ✗ gcc -c test.S
➜  kernel-all git:(master) ✗ objdump -D test.o

test.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <.text>:
   0:	48 31 c9             	xor    %rcx,%rcx
➜  kernel-all git:(master) ✗ clang -c test.S  
test.S:1:13: error: unknown token in expression
var_xdata = %rcx
            ^
test.S:1:13: error: missing expression
var_xdata = %rcx
            ^
test.S:3:17: error: invalid operand for instruction
xorq var_xdata, var_xdata
^

nickdesaulniers · 2018-05-11T20:21:00Z

https://llvm.org/pr37425

nickdesaulniers · 2018-05-11T20:31:49Z

A suggestion was to use the .set directive, but that also seems to choke.

nickdesaulniers · 2018-06-07T17:39:54Z

Still need to test, but looks like a fix went into clang-7: https://llvm.org/pr37425

nickdesaulniers · 2018-06-07T17:40:33Z

Thanks @niravhdave 🎉 🎆 🍾

Increase kasan instrumented kernel stack size from 32k to 64k. Other architectures seems to get away with just doubling kernel stack size under kasan, but on s390 this appears to be not enough due to bigger frame size. The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting stack overflow is fs sync on xfs filesystem: #0 [9a0681e8] 704 bytes check_usage at 34b1fc #1 [9a0684a8] 432 bytes check_usage at 34c710 #2 [9a068658] 1048 bytes validate_chain at 35044a #3 [9a068a70] 312 bytes __lock_acquire at 3559fe #4 [9a068ba8] 440 bytes lock_acquire at 3576ee #5 [9a068d60] 104 bytes _raw_spin_lock at 21b44e0 #6 [9a068dc8] 1992 bytes enqueue_entity at 2dbf72 #7 [9a069590] 1496 bytes enqueue_task_fair at 2df5f0 #8 [9a069b68] 64 bytes ttwu_do_activate at 28f438 #9 [9a069ba8] 552 bytes try_to_wake_up at 298c4c #10 [9a069dd0] 168 bytes wake_up_worker at 23f97c #11 [9a069e78] 200 bytes insert_work at 23fc2e #12 [9a069f40] 648 bytes __queue_work at 2487c0 #13 [9a06a1c8] 200 bytes __queue_delayed_work at 24db28 #14 [9a06a290] 248 bytes mod_delayed_work_on at 24de84 #15 [9a06a388] 24 bytes kblockd_mod_delayed_work_on at 153e2a0 #16 [9a06a3a0] 288 bytes __blk_mq_delay_run_hw_queue at 158168c #17 [9a06a4c0] 192 bytes blk_mq_run_hw_queue at 1581a3c #18 [9a06a580] 184 bytes blk_mq_sched_insert_requests at 15a2192 #19 [9a06a638] 1024 bytes blk_mq_flush_plug_list at 1590f3a #20 [9a06aa38] 704 bytes blk_flush_plug_list at 1555028 #21 [9a06acf8] 320 bytes schedule at 219e476 #22 [9a06ae38] 760 bytes schedule_timeout at 21b0aac #23 [9a06b130] 408 bytes wait_for_common at 21a1706 #24 [9a06b2c8] 360 bytes xfs_buf_iowait at fa1540 #25 [9a06b430] 256 bytes __xfs_buf_submit at fadae6 #26 [9a06b530] 264 bytes xfs_buf_read_map at fae3f6 #27 [9a06b638] 656 bytes xfs_trans_read_buf_map at 10ac9a8 #28 [9a06b8c8] 304 bytes xfs_btree_kill_root at e72426 #29 [9a06b9f8] 288 bytes xfs_btree_lookup_get_block at e7bc5e #30 [9a06bb18] 624 bytes xfs_btree_lookup at e7e1a6 #31 [9a06bd88] 2664 bytes xfs_alloc_ag_vextent_near at dfa070 #32 [9a06c7f0] 144 bytes xfs_alloc_ag_vextent at dff3ca #33 [9a06c880] 1128 bytes xfs_alloc_vextent at e05fce #34 [9a06cce8] 584 bytes xfs_bmap_btalloc at e58342 #35 [9a06cf30] 1336 bytes xfs_bmapi_write at e618de #36 [9a06d468] 776 bytes xfs_iomap_write_allocate at ff678e #37 [9a06d770] 720 bytes xfs_map_blocks at f82af8 #38 [9a06da40] 928 bytes xfs_writepage_map at f83cd6 #39 [9a06dde0] 320 bytes xfs_do_writepage at f85872 #40 [9a06df20] 1320 bytes write_cache_pages at 73dfe8 #41 [9a06e448] 208 bytes xfs_vm_writepages at f7f892 #42 [9a06e518] 88 bytes do_writepages at 73fe6a #43 [9a06e570] 872 bytes __writeback_single_inode at a20cb6 #44 [9a06e8d8] 664 bytes writeback_sb_inodes at a23be2 #45 [9a06eb70] 296 bytes __writeback_inodes_wb at a242e0 #46 [9a06ec98] 928 bytes wb_writeback at a2500e #47 [9a06f038] 848 bytes wb_do_writeback at a260ae #48 [9a06f388] 536 bytes wb_workfn at a28228 #49 [9a06f5a0] 1088 bytes process_one_work at 24a234 #50 [9a06f9e0] 1120 bytes worker_thread at 24ba26 #51 [9a06fe40] 104 bytes kthread at 26545a #52 [9a06fea8] kernel_thread_starter at 21b6b62 To be able to increase the stack size to 64k reuse LLILL instruction in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE (65192) value as unsigned. Reported-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

…r-free issue The evlist should be destroyed before the perf session. Detected with gcc's ASan: ================================================================= ==27350==ERROR: AddressSanitizer: heap-use-after-free on address 0x62b000002e38 at pc 0x5611da276999 bp 0x7ffce8f1d1a0 sp 0x7ffce8f1d190 WRITE of size 8 at 0x62b000002e38 thread T0 #0 0x5611da276998 in __list_del /home/work/linux/tools/include/linux/list.h:89 #1 0x5611da276d4a in __list_del_entry /home/work/linux/tools/include/linux/list.h:102 #2 0x5611da276e77 in list_del_init /home/work/linux/tools/include/linux/list.h:145 #3 0x5611da2781cd in thread__put util/thread.c:130 #4 0x5611da2cc0a8 in __thread__zput util/thread.h:68 #5 0x5611da2d2dcb in hist_entry__delete util/hist.c:1148 #6 0x5611da2cdf91 in hists__delete_entry util/hist.c:337 #7 0x5611da2ce19e in hists__delete_entries util/hist.c:365 #8 0x5611da2db2ab in hists__delete_all_entries util/hist.c:2639 #9 0x5611da2db325 in hists_evsel__exit util/hist.c:2651 #10 0x5611da1c5352 in perf_evsel__exit util/evsel.c:1304 #11 0x5611da1c5390 in perf_evsel__delete util/evsel.c:1309 #12 0x5611da1b35f0 in perf_evlist__purge util/evlist.c:124 #13 0x5611da1b38e2 in perf_evlist__delete util/evlist.c:148 #14 0x5611da069781 in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1645 #15 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #16 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #17 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #18 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #19 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) #20 0x5611d9ff35c9 in _start (/home/work/linux/tools/perf/perf+0x3e95c9) 0x62b000002e38 is located 11320 bytes inside of 27448-byte region [0x62b000000200,0x62b000006d38) freed by thread T0 here: #0 0x7fdccb04ab70 in free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedb70) #1 0x5611da260df4 in perf_session__delete util/session.c:201 #2 0x5611da063de5 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1300 #3 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 #4 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #5 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #6 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #7 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #8 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) previously allocated by thread T0 here: #0 0x7fdccb04b138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) #1 0x5611da26010c in zalloc util/util.h:23 #2 0x5611da260824 in perf_session__new util/session.c:118 #3 0x5611da0633a6 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1192 #4 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 #5 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #6 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #7 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #8 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #9 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) SUMMARY: AddressSanitizer: heap-use-after-free /home/work/linux/tools/include/linux/list.h:89 in __list_del Shadow bytes around the buggy address: 0x0c567fff8570: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8580: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8590: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85a0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd =>0x0c567fff85c0: fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd 0x0c567fff85d0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85e0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8610: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==27350==ABORTING Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190316080556.3075-8-changbin.du@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

A recently introduced helper for handling zap vs. remote flush incorrectly bails early, effectively leaking defunct shadow pages. Manifests as a slab BUG when exiting KVM due to the shadow pages being alive when their associated cache is destroyed. ========================================================================== BUG kvm_mmu_page_header: Objects remaining in kvm_mmu_page_header on ... -------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Slab 0x00000000fc436387 objects=26 used=23 fp=0x00000000d023caee ... CPU: 6 PID: 4315 Comm: rmmod Tainted: G B 5.1.0-rc2+ #19 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack+0x46/0x5b slab_err+0xad/0xd0 ? on_each_cpu_mask+0x3c/0x50 ? ksm_migrate_page+0x60/0x60 ? on_each_cpu_cond_mask+0x7c/0xa0 ? __kmalloc+0x1ca/0x1e0 __kmem_cache_shutdown+0x13a/0x310 shutdown_cache+0xf/0x130 kmem_cache_destroy+0x1d5/0x200 kvm_mmu_module_exit+0xa/0x30 [kvm] kvm_arch_exit+0x45/0x60 [kvm] kvm_exit+0x6f/0x80 [kvm] vmx_exit+0x1a/0x50 [kvm_intel] __x64_sys_delete_module+0x153/0x1f0 ? exit_to_usermode_loop+0x88/0xc0 do_syscall_64+0x4f/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: a211363 ("KVM: x86/mmu: Split remote_flush+zap case out of kvm_mmu_flush_or_zap()") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

spdxcheck.py complains: drivers/power/supply/goldfish_battery.c: 1:28 Invalid License ID: GPL which is correct because GPL is not a valid identifier. Of course this could have been caught by checkpatch.pl _before_ submitting or merging the patch. WARNING: 'SPDX-License-Identifier: GPL' is not supported in LICENSES/... #19: FILE: drivers/power/supply/goldfish_battery.c:1: +// SPDX-License-Identifier: GPL Which is absolutely hillarious as the commit introducing this wreckage says in the changelog: There was a checkpatch complain: "Missing or malformed SPDX-License-Identifier tag". Oh well. Replacing a checkpatch warning by a different checkpatch warning is a really useful exercise. Use the proper GPL-2.0 identifier which is what the boiler plate in the file had originally. Fixes: e75e3a1 ("drivers: power: supply: goldfish_battery: Put an SPDX tag") Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

If io_allocate_scq_urings() fails to allocate an sq_* region, it will call io_mem_free() for any previously allocated regions, but leave dangling pointers to these regions in the ctx. Any regions which have not yet been allocated are left NULL. Note that when returning -EOVERFLOW, the previously allocated sq_ring is not freed, which appears to be an unintentional leak. When io_allocate_scq_urings() fails, io_uring_create() will call io_ring_ctx_wait_and_kill(), which calls io_mem_free() on all the sq_* regions, assuming the pointers are valid and not NULL. This can result in pages being freed multiple times, which has been observed to corrupt the page state, leading to subsequent fun. This can also result in virt_to_page() on NULL, resulting in the use of bogus page addresses, and yet more subsequent fun. The latter can be detected with CONFIG_DEBUG_VIRTUAL on arm64. Adding a cleanup path to io_allocate_scq_urings() complicates the logic, so let's leave it to io_ring_ctx_free() to consistently free these pointers, and simplify the io_allocate_scq_urings() error paths. Full splats from before this patch below. Note that the pointer logged by the DEBUG_VIRTUAL "non-linear address" warning has been hashed, and is actually NULL. [ 26.098129] page:ffff80000e949a00 count:0 mapcount:-128 mapping:0000000000000000 index:0x0 [ 26.102976] flags: 0x63fffc000000() [ 26.104373] raw: 000063fffc000000 ffff80000e86c188 ffff80000ea3df08 0000000000000000 [ 26.108917] raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000 [ 26.137235] page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) [ 26.143960] ------------[ cut here ]------------ [ 26.146020] kernel BUG at include/linux/mm.h:547! [ 26.147586] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [ 26.149163] Modules linked in: [ 26.150287] Process syz-executor.21 (pid: 20204, stack limit = 0x000000000e9cefeb) [ 26.153307] CPU: 2 PID: 20204 Comm: syz-executor.21 Not tainted 5.1.0-rc7-00004-g7d30b2ea43d6 #18 [ 26.156566] Hardware name: linux,dummy-virt (DT) [ 26.158089] pstate: 40400005 (nZcv daif +PAN -UAO) [ 26.159869] pc : io_mem_free+0x9c/0xa8 [ 26.161436] lr : io_mem_free+0x9c/0xa8 [ 26.162720] sp : ffff000013003d60 [ 26.164048] x29: ffff000013003d60 x28: ffff800025048040 [ 26.165804] x27: 0000000000000000 x26: ffff800025048040 [ 26.167352] x25: 00000000000000c0 x24: ffff0000112c2820 [ 26.169682] x23: 0000000000000000 x22: 0000000020000080 [ 26.171899] x21: ffff80002143b418 x20: ffff80002143b400 [ 26.174236] x19: ffff80002143b280 x18: 0000000000000000 [ 26.176607] x17: 0000000000000000 x16: 0000000000000000 [ 26.178997] x15: 0000000000000000 x14: 0000000000000000 [ 26.181508] x13: 00009178a5e077b2 x12: 0000000000000001 [ 26.183863] x11: 0000000000000000 x10: 0000000000000980 [ 26.186437] x9 : ffff000013003a80 x8 : ffff800025048a20 [ 26.189006] x7 : ffff8000250481c0 x6 : ffff80002ffe9118 [ 26.191359] x5 : ffff80002ffe9118 x4 : 0000000000000000 [ 26.193863] x3 : ffff80002ffefe98 x2 : 44c06ddd107d1f00 [ 26.196642] x1 : 0000000000000000 x0 : 000000000000003e [ 26.198892] Call trace: [ 26.199893] io_mem_free+0x9c/0xa8 [ 26.201155] io_ring_ctx_wait_and_kill+0xec/0x180 [ 26.202688] io_uring_setup+0x6c4/0x6f0 [ 26.204091] __arm64_sys_io_uring_setup+0x18/0x20 [ 26.205576] el0_svc_common.constprop.0+0x7c/0xe8 [ 26.207186] el0_svc_handler+0x28/0x78 [ 26.208389] el0_svc+0x8/0xc [ 26.209408] Code: aa0203e0 d0006861 9133a021 97fcdc3c (d4210000) [ 26.211995] ---[ end trace bdb81cd43a21e50d ]--- [ 81.770626] ------------[ cut here ]------------ [ 81.825015] virt_to_phys used for non-linear address: 000000000d42f2c7 ( (null)) [ 81.827860] WARNING: CPU: 1 PID: 30171 at arch/arm64/mm/physaddr.c:15 __virt_to_phys+0x48/0x68 [ 81.831202] Modules linked in: [ 81.832212] CPU: 1 PID: 30171 Comm: syz-executor.20 Not tainted 5.1.0-rc7-00004-g7d30b2ea43d6 #19 [ 81.835616] Hardware name: linux,dummy-virt (DT) [ 81.836863] pstate: 60400005 (nZCv daif +PAN -UAO) [ 81.838727] pc : __virt_to_phys+0x48/0x68 [ 81.840572] lr : __virt_to_phys+0x48/0x68 [ 81.842264] sp : ffff80002cf67c70 [ 81.843858] x29: ffff80002cf67c70 x28: ffff800014358e18 [ 81.846463] x27: 0000000000000000 x26: 0000000020000080 [ 81.849148] x25: 0000000000000000 x24: ffff80001bb01f40 [ 81.851986] x23: ffff200011db06c8 x22: ffff2000127e3c60 [ 81.854351] x21: ffff800014358cc0 x20: ffff800014358d98 [ 81.856711] x19: 0000000000000000 x18: 0000000000000000 [ 81.859132] x17: 0000000000000000 x16: 0000000000000000 [ 81.861586] x15: 0000000000000000 x14: 0000000000000000 [ 81.863905] x13: 0000000000000000 x12: ffff1000037603e9 [ 81.866226] x11: 1ffff000037603e8 x10: 0000000000000980 [ 81.868776] x9 : ffff80002cf67840 x8 : ffff80001bb02920 [ 81.873272] x7 : ffff1000037603e9 x6 : ffff80001bb01f47 [ 81.875266] x5 : ffff1000037603e9 x4 : dfff200000000000 [ 81.876875] x3 : ffff200010087528 x2 : ffff1000059ecf58 [ 81.878751] x1 : 44c06ddd107d1f00 x0 : 0000000000000000 [ 81.880453] Call trace: [ 81.881164] __virt_to_phys+0x48/0x68 [ 81.882919] io_mem_free+0x18/0x110 [ 81.886585] io_ring_ctx_wait_and_kill+0x13c/0x1f0 [ 81.891212] io_uring_setup+0xa60/0xad0 [ 81.892881] __arm64_sys_io_uring_setup+0x2c/0x38 [ 81.894398] el0_svc_common.constprop.0+0xac/0x150 [ 81.896306] el0_svc_handler+0x34/0x88 [ 81.897744] el0_svc+0x8/0xc [ 81.898715] ---[ end trace b4a703802243cbba ]--- Fixes: 2b188cc ("Add io_uring IO interface") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: linux-block@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>

A deadlock with this stacktrace was observed. The loop thread does a GFP_KERNEL allocation, it calls into dm-bufio shrinker and the shrinker depends on I/O completion in the dm-bufio subsystem. In order to fix the deadlock (and other similar ones), we set the flag PF_MEMALLOC_NOIO at loop thread entry. PID: 474 TASK: ffff8813e11f4600 CPU: 10 COMMAND: "kswapd0" #0 [ffff8813dedfb938] __schedule at ffffffff8173f405 #1 [ffff8813dedfb990] schedule at ffffffff8173fa27 #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186 #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8 #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81 #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio] #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio] #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio] #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778 #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f #13 [ffff8813dedfbec0] kthread at ffffffff810a8428 #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242 PID: 14127 TASK: ffff881455749c00 CPU: 11 COMMAND: "loop1" #0 [ffff88272f5af228] __schedule at ffffffff8173f405 #1 [ffff88272f5af280] schedule at ffffffff8173fa27 #2 [ffff88272f5af2a0] schedule_preempt_disabled at ffffffff8173fd5e #3 [ffff88272f5af2b0] __mutex_lock_slowpath at ffffffff81741fb5 #4 [ffff88272f5af330] mutex_lock at ffffffff81742133 #5 [ffff88272f5af350] dm_bufio_shrink_count at ffffffffa03865f9 [dm_bufio] #6 [ffff88272f5af380] shrink_slab at ffffffff811a86bd #7 [ffff88272f5af470] shrink_zone at ffffffff811ad778 #8 [ffff88272f5af500] do_try_to_free_pages at ffffffff811adb34 #9 [ffff88272f5af590] try_to_free_pages at ffffffff811adef8 #10 [ffff88272f5af610] __alloc_pages_nodemask at ffffffff811a09c3 #11 [ffff88272f5af710] alloc_pages_current at ffffffff811e8b71 #12 [ffff88272f5af760] new_slab at ffffffff811f4523 #13 [ffff88272f5af7b0] __slab_alloc at ffffffff8173a1b5 #14 [ffff88272f5af880] kmem_cache_alloc at ffffffff811f484b #15 [ffff88272f5af8d0] do_blockdev_direct_IO at ffffffff812535b3 #16 [ffff88272f5afb00] __blockdev_direct_IO at ffffffff81255dc3 #17 [ffff88272f5afb30] xfs_vm_direct_IO at ffffffffa01fe3fc [xfs] #18 [ffff88272f5afb90] generic_file_read_iter at ffffffff81198994 #19 [ffff88272f5afc50] __dta_xfs_file_read_iter_2398 at ffffffffa020c970 [xfs] #20 [ffff88272f5afcc0] lo_rw_aio at ffffffffa0377042 [loop] #21 [ffff88272f5afd70] loop_queue_work at ffffffffa0377c3b [loop] #22 [ffff88272f5afe60] kthread_worker_fn at ffffffff810a8a0c #23 [ffff88272f5afec0] kthread at ffffffff810a8428 #24 [ffff88272f5aff50] ret_from_fork at ffffffff81745242 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>

By reusing the "connect" BPF collector. Testing it system wide and stopping/starting sshd: # perf trace -e bind LLVM: dumping /home/acme/git/perf/tools/perf/examples/bpf/augmented_raw_syscalls.o DNS Res~er #18/15132 bind(243, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #19/4833 bind(247, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #19/4833 bind(238, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #18/15132 bind(243, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #18/10327 bind(258, { .family: PF_NETLINK }, 12) = 0 :6507/6507 bind(24, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #19/4833 bind(238, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #18/15132 bind(242, { .family: PF_NETLINK }, 12) = 0 sshd/6514 bind(3, { .family: PF_NETLINK }, 12) = 0 sshd/6514 bind(5, { .family: PF_INET, port: 22, addr: 0.0.0.0 }, 16) = 0 sshd/6514 bind(7, { .family: PF_INET6, port: 22, addr: :: }, 28) = 0 DNS Res~er #18/10327 bind(229, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #18/15132 bind(231, { .family: PF_NETLINK }, 12) = 0 DNS Res~er #19/4833 bind(229, { .family: PF_NETLINK }, 12) = 0 ^C# Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lkml.kernel.org/n/tip-m2hmxqrckxxw2ciki0tu889u@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Commit <684d984038aa> ('powerpc/powernv: Add debugfs interface for imc-mode and imc') added debugfs interface for the nest imc pmu devices to support changing of different ucode modes. Primarily adding this capability for debug. But when doing so, the code did not consider the case of cpu-less nodes. So when reading the _cmd_ or _mode_ file of a cpu-less node will create this crash. Faulting instruction address: 0xc0000000000d0d58 Oops: Kernel access of bad area, sig: 11 [#1] ... CPU: 67 PID: 5301 Comm: cat Not tainted 5.2.0-rc6-next-20190627+ #19 NIP: c0000000000d0d58 LR: c00000000049aa18 CTR:c0000000000d0d50 REGS: c00020194548f9e0 TRAP: 0300 Not tainted (5.2.0-rc6-next-20190627+) MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR:28022822 XER: 00000000 CFAR: c00000000049aa14 DAR: 000000000003fc08 DSISR:40000000 IRQMASK: 0 ... NIP imc_mem_get+0x8/0x20 LR simple_attr_read+0x118/0x170 Call Trace: simple_attr_read+0x70/0x170 (unreliable) debugfs_attr_read+0x6c/0xb0 __vfs_read+0x3c/0x70 vfs_read+0xbc/0x1a0 ksys_read+0x7c/0x140 system_call+0x5c/0x70 Patch fixes the issue with a more robust check for vbase to NULL. Before patch, ls output for the debugfs imc directory # ls /sys/kernel/debug/powerpc/imc/ imc_cmd_0 imc_cmd_251 imc_cmd_253 imc_cmd_255 imc_mode_0 imc_mode_251 imc_mode_253 imc_mode_255 imc_cmd_250 imc_cmd_252 imc_cmd_254 imc_cmd_8 imc_mode_250 imc_mode_252 imc_mode_254 imc_mode_8 After patch, ls output for the debugfs imc directory # ls /sys/kernel/debug/powerpc/imc/ imc_cmd_0 imc_cmd_8 imc_mode_0 imc_mode_8 Actual bug here is that, we have two loops with potentially different loop counts. That is, in imc_get_mem_addr_nest(), loop count is obtained from the dt entries. But in case of export_imc_mode_and_cmd(), loop was based on for_each_nid() count. Patch fixes the loop count in latter based on the struct mem_info. Ideally it would be better to have array size in struct imc_pmu. Fixes: 684d984 ('powerpc/powernv: Add debugfs interface for imc-mode and imc') Reported-by: Qian Cai <cai@lca.pw> Suggested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20190827101635.6942-1-maddy@linux.vnet.ibm.com

Masoud Sharbiani noticed that commit 29ef680 ("memcg, oom: move out_of_memory back to the charge path") broke memcg OOM called from __xfs_filemap_fault() path. It turned out that try_charge() is retrying forever without making forward progress because mem_cgroup_oom(GFP_NOFS) cannot invoke the OOM killer due to commit 3da88fb ("mm, oom: move GFP_NOFS check to out_of_memory"). Allowing forced charge due to being unable to invoke memcg OOM killer will lead to global OOM situation. Also, just returning -ENOMEM will be risky because OOM path is lost and some paths (e.g. get_user_pages()) will leak -ENOMEM. Therefore, invoking memcg OOM killer (despite GFP_NOFS) will be the only choice we can choose for now. Until 29ef680, we were able to invoke memcg OOM killer when GFP_KERNEL reclaim failed [1]. But since 29ef680, we need to invoke memcg OOM killer when GFP_NOFS reclaim failed [2]. Although in the past we did invoke memcg OOM killer for GFP_NOFS [3], we might get pre-mature memcg OOM reports due to this patch. [1] leaker invoked oom-killer: gfp_mask=0x6200ca(GFP_HIGHUSER_MOVABLE), nodemask=(null), order=0, oom_score_adj=0 CPU: 0 PID: 2746 Comm: leaker Not tainted 4.18.0+ #19 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/13/2018 Call Trace: dump_stack+0x63/0x88 dump_header+0x67/0x27a ? mem_cgroup_scan_tasks+0x91/0xf0 oom_kill_process+0x210/0x410 out_of_memory+0x10a/0x2c0 mem_cgroup_out_of_memory+0x46/0x80 mem_cgroup_oom_synchronize+0x2e4/0x310 ? high_work_func+0x20/0x20 pagefault_out_of_memory+0x31/0x76 mm_fault_error+0x55/0x115 ? handle_mm_fault+0xfd/0x220 __do_page_fault+0x433/0x4e0 do_page_fault+0x22/0x30 ? page_fault+0x8/0x30 page_fault+0x1e/0x30 RIP: 0033:0x4009f0 Code: 03 00 00 00 e8 71 fd ff ff 48 83 f8 ff 49 89 c6 74 74 48 89 c6 bf c0 0c 40 00 31 c0 e8 69 fd ff ff 45 85 ff 7e 21 31 c9 66 90 <41> 0f be 14 0e 01 d3 f7 c1 ff 0f 00 00 75 05 41 c6 04 0e 2a 48 83 RSP: 002b:00007ffe29ae96f0 EFLAGS: 00010206 RAX: 000000000000001b RBX: 0000000000000000 RCX: 0000000001ce1000 RDX: 0000000000000000 RSI: 000000007fffffe5 RDI: 0000000000000000 RBP: 000000000000000c R08: 0000000000000000 R09: 00007f94be09220d R10: 0000000000000002 R11: 0000000000000246 R12: 00000000000186a0 R13: 0000000000000003 R14: 00007f949d845000 R15: 0000000002800000 Task in /leaker killed as a result of limit of /leaker memory: usage 524288kB, limit 524288kB, failcnt 158965 memory+swap: usage 0kB, limit 9007199254740988kB, failcnt 0 kmem: usage 2016kB, limit 9007199254740988kB, failcnt 0 Memory cgroup stats for /leaker: cache:844KB rss:521136KB rss_huge:0KB shmem:0KB mapped_file:0KB dirty:132KB writeback:0KB inactive_anon:0KB active_anon:521224KB inactive_file:1012KB active_file:8KB unevictable:0KB Memory cgroup out of memory: Kill process 2746 (leaker) score 998 or sacrifice child Killed process 2746 (leaker) total-vm:536704kB, anon-rss:521176kB, file-rss:1208kB, shmem-rss:0kB oom_reaper: reaped process 2746 (leaker), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [2] leaker invoked oom-killer: gfp_mask=0x600040(GFP_NOFS), nodemask=(null), order=0, oom_score_adj=0 CPU: 1 PID: 2746 Comm: leaker Not tainted 4.18.0+ #20 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/13/2018 Call Trace: dump_stack+0x63/0x88 dump_header+0x67/0x27a ? mem_cgroup_scan_tasks+0x91/0xf0 oom_kill_process+0x210/0x410 out_of_memory+0x109/0x2d0 mem_cgroup_out_of_memory+0x46/0x80 try_charge+0x58d/0x650 ? __radix_tree_replace+0x81/0x100 mem_cgroup_try_charge+0x7a/0x100 __add_to_page_cache_locked+0x92/0x180 add_to_page_cache_lru+0x4d/0xf0 iomap_readpages_actor+0xde/0x1b0 ? iomap_zero_range_actor+0x1d0/0x1d0 iomap_apply+0xaf/0x130 iomap_readpages+0x9f/0x150 ? iomap_zero_range_actor+0x1d0/0x1d0 xfs_vm_readpages+0x18/0x20 [xfs] read_pages+0x60/0x140 __do_page_cache_readahead+0x193/0x1b0 ondemand_readahead+0x16d/0x2c0 page_cache_async_readahead+0x9a/0xd0 filemap_fault+0x403/0x620 ? alloc_set_pte+0x12c/0x540 ? _cond_resched+0x14/0x30 __xfs_filemap_fault+0x66/0x180 [xfs] xfs_filemap_fault+0x27/0x30 [xfs] __do_fault+0x19/0x40 __handle_mm_fault+0x8e8/0xb60 handle_mm_fault+0xfd/0x220 __do_page_fault+0x238/0x4e0 do_page_fault+0x22/0x30 ? page_fault+0x8/0x30 page_fault+0x1e/0x30 RIP: 0033:0x4009f0 Code: 03 00 00 00 e8 71 fd ff ff 48 83 f8 ff 49 89 c6 74 74 48 89 c6 bf c0 0c 40 00 31 c0 e8 69 fd ff ff 45 85 ff 7e 21 31 c9 66 90 <41> 0f be 14 0e 01 d3 f7 c1 ff 0f 00 00 75 05 41 c6 04 0e 2a 48 83 RSP: 002b:00007ffda45c9290 EFLAGS: 00010206 RAX: 000000000000001b RBX: 0000000000000000 RCX: 0000000001a1e000 RDX: 0000000000000000 RSI: 000000007fffffe5 RDI: 0000000000000000 RBP: 000000000000000c R08: 0000000000000000 R09: 00007f6d061ff20d R10: 0000000000000002 R11: 0000000000000246 R12: 00000000000186a0 R13: 0000000000000003 R14: 00007f6ce59b2000 R15: 0000000002800000 Task in /leaker killed as a result of limit of /leaker memory: usage 524288kB, limit 524288kB, failcnt 7221 memory+swap: usage 0kB, limit 9007199254740988kB, failcnt 0 kmem: usage 1944kB, limit 9007199254740988kB, failcnt 0 Memory cgroup stats for /leaker: cache:3632KB rss:518232KB rss_huge:0KB shmem:0KB mapped_file:0KB dirty:0KB writeback:0KB inactive_anon:0KB active_anon:518408KB inactive_file:3908KB active_file:12KB unevictable:0KB Memory cgroup out of memory: Kill process 2746 (leaker) score 992 or sacrifice child Killed process 2746 (leaker) total-vm:536704kB, anon-rss:518264kB, file-rss:1188kB, shmem-rss:0kB oom_reaper: reaped process 2746 (leaker), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB [3] leaker invoked oom-killer: gfp_mask=0x50, order=0, oom_score_adj=0 leaker cpuset=/ mems_allowed=0 CPU: 1 PID: 3206 Comm: leaker Not tainted 3.10.0-957.27.2.el7.x86_64 #1 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/13/2018 Call Trace: [<ffffffffaf364147>] dump_stack+0x19/0x1b [<ffffffffaf35eb6a>] dump_header+0x90/0x229 [<ffffffffaedbb456>] ? find_lock_task_mm+0x56/0xc0 [<ffffffffaee32a38>] ? try_get_mem_cgroup_from_mm+0x28/0x60 [<ffffffffaedbb904>] oom_kill_process+0x254/0x3d0 [<ffffffffaee36c36>] mem_cgroup_oom_synchronize+0x546/0x570 [<ffffffffaee360b0>] ? mem_cgroup_charge_common+0xc0/0xc0 [<ffffffffaedbc194>] pagefault_out_of_memory+0x14/0x90 [<ffffffffaf35d072>] mm_fault_error+0x6a/0x157 [<ffffffffaf3717c8>] __do_page_fault+0x3c8/0x4f0 [<ffffffffaf371925>] do_page_fault+0x35/0x90 [<ffffffffaf36d768>] page_fault+0x28/0x30 Task in /leaker killed as a result of limit of /leaker memory: usage 524288kB, limit 524288kB, failcnt 20628 memory+swap: usage 524288kB, limit 9007199254740988kB, failcnt 0 kmem: usage 0kB, limit 9007199254740988kB, failcnt 0 Memory cgroup stats for /leaker: cache:840KB rss:523448KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:523448KB inactive_file:464KB active_file:376KB unevictable:0KB Memory cgroup out of memory: Kill process 3206 (leaker) score 970 or sacrifice child Killed process 3206 (leaker) total-vm:536692kB, anon-rss:523304kB, file-rss:412kB, shmem-rss:0kB Bisected by Masoud Sharbiani. Link: http://lkml.kernel.org/r/cbe54ed1-b6ba-a056-8899-2dc42526371d@i-love.sakura.ne.jp Fixes: 3da88fb ("mm, oom: move GFP_NOFS check to out_of_memory") [necessary after 29ef680] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Masoud Sharbiani <msharbiani@apple.com> Tested-by: Masoud Sharbiani <msharbiani@apple.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [4.19+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When the client hits reconnect it iterates over the mid pending queue marking entries for retry and moving them to a temporary list to issue callbacks later without holding GlobalMid_Lock. In the same time there is no guarantee that mids can't be removed from the temporary list or even freed completely by another thread. It may cause a temporary list corruption: [ 430.454897] list_del corruption. prev->next should be ffff98d3a8f316c0, but was 2e885cb266355469 [ 430.464668] ------------[ cut here ]------------ [ 430.466569] kernel BUG at lib/list_debug.c:51! [ 430.468476] invalid opcode: 0000 [#1] SMP PTI [ 430.470286] CPU: 0 PID: 13267 Comm: cifsd Kdump: loaded Not tainted 5.4.0-rc3+ #19 [ 430.473472] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 430.475872] RIP: 0010:__list_del_entry_valid.cold+0x31/0x55 ... [ 430.510426] Call Trace: [ 430.511500] cifs_reconnect+0x25e/0x610 [cifs] [ 430.513350] cifs_readv_from_socket+0x220/0x250 [cifs] [ 430.515464] cifs_read_from_socket+0x4a/0x70 [cifs] [ 430.517452] ? try_to_wake_up+0x212/0x650 [ 430.519122] ? cifs_small_buf_get+0x16/0x30 [cifs] [ 430.521086] ? allocate_buffers+0x66/0x120 [cifs] [ 430.523019] cifs_demultiplex_thread+0xdc/0xc30 [cifs] [ 430.525116] kthread+0xfb/0x130 [ 430.526421] ? cifs_handle_standard+0x190/0x190 [cifs] [ 430.528514] ? kthread_park+0x90/0x90 [ 430.530019] ret_from_fork+0x35/0x40 Fix this by obtaining extra references for mids being retried and marking them as MID_DELETED which indicates that such a mid has been dequeued from the pending list. Also move mid cleanup logic from DeleteMidQEntry to _cifs_mid_q_entry_release which is called when the last reference to a particular mid is put. This allows to avoid any use-after-free of response buffers. The patch needs to be backported to stable kernels. A stable tag is not mentioned below because the patch doesn't apply cleanly to any actively maintained stable kernel. Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-and-tested-by: David Wysochanski <dwysocha@redhat.com> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>

Add ability to specify a list of test name substrings for selecting which tests to run. So now -t is accepting a comma-separated list of strings, similarly to how -n accepts a comma-separated list of test numbers. Additionally, add ability to blacklist tests by name. Blacklist takes precedence over whitelist. Blacklisting is important for cases where it's known that some tests can't pass (e.g., due to perf hardware events that are not available within VM). This is going to be used for libbpf testing in Travis CI in its Github repo. Example runs with just whitelist and whitelist + blacklist: $ sudo ./test_progs -tattach,core/existence #1 attach_probe:OK #6 cgroup_attach_autodetach:OK #7 cgroup_attach_multi:OK #8 cgroup_attach_override:OK #9 core_extern:OK #10/44 existence:OK #10/45 existence___minimal:OK #10/46 existence__err_int_sz:OK #10/47 existence__err_int_type:OK #10/48 existence__err_int_kind:OK #10/49 existence__err_arr_kind:OK #10/50 existence__err_arr_value_type:OK #10/51 existence__err_struct_type:OK #10 core_reloc:OK #19 flow_dissector_reattach:OK #60 tp_attach_query:OK Summary: 8/8 PASSED, 0 SKIPPED, 0 FAILED $ sudo ./test_progs -tattach,core/existence -bcgroup,flow/arr #1 attach_probe:OK #9 core_extern:OK #10/44 existence:OK #10/45 existence___minimal:OK #10/46 existence__err_int_sz:OK #10/47 existence__err_int_type:OK #10/48 existence__err_int_kind:OK #10/51 existence__err_struct_type:OK #10 core_reloc:OK #60 tp_attach_query:OK Summary: 4/6 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Julia Kartseva <hex@fb.com> Link: https://lore.kernel.org/bpf/20200116005549.3644118-1-andriin@fb.com

When experimenting with bpf_send_signal() helper in our production environment (5.2 based), we experienced a deadlock in NMI mode: #5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24 #6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012 #7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd #8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55 #9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602 #10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a #11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227 #12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140 #13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf #14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09 #15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47 #16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d #17 [ffffc9002219fc90] schedule at ffffffff81a3e219 #18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9 #19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529 #20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc #21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c #22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602 #23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068 The above call stack is actually very similar to an issue reported by Commit eac9153 ("bpf/stackmap: Fix deadlock with rq_lock in bpf_get_stack()") by Song Liu. The only difference is bpf_send_signal() helper instead of bpf_get_stack() helper. The above deadlock is triggered with a perf_sw_event. Similar to Commit eac9153, the below almost identical reproducer used tracepoint point sched/sched_switch so the issue can be easily caught. /* stress_test.c */ #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <pthread.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #define THREAD_COUNT 1000 char *filename; void *worker(void *p) { void *ptr; int fd; char *pptr; fd = open(filename, O_RDONLY); if (fd < 0) return NULL; while (1) { struct timespec ts = {0, 1000 + rand() % 2000}; ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0); usleep(1); if (ptr == MAP_FAILED) { printf("failed to mmap\n"); break; } munmap(ptr, 4096 * 64); usleep(1); pptr = malloc(1); usleep(1); pptr[0] = 1; usleep(1); free(pptr); usleep(1); nanosleep(&ts, NULL); } close(fd); return NULL; } int main(int argc, char *argv[]) { void *ptr; int i; pthread_t threads[THREAD_COUNT]; if (argc < 2) return 0; filename = argv[1]; for (i = 0; i < THREAD_COUNT; i++) { if (pthread_create(threads + i, NULL, worker, NULL)) { fprintf(stderr, "Error creating thread\n"); return 0; } } for (i = 0; i < THREAD_COUNT; i++) pthread_join(threads[i], NULL); return 0; } and the following command: 1. run `stress_test /bin/ls` in one windown 2. hack bcc trace.py with the following change: --- a/tools/trace.py +++ b/tools/trace.py @@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s); __data.tgid = __tgid; __data.pid = __pid; bpf_get_current_comm(&__data.comm, sizeof(__data.comm)); + bpf_send_signal(10); %s %s %s.perf_submit(%s, &__data, sizeof(__data)); 3. in a different window run ./trace.py -p $(pidof stress_test) t:sched:sched_switch The deadlock can be reproduced in our production system. Similar to Song's fix, the fix is to delay sending signal if irqs is disabled to avoid deadlocks involving with rq_lock. With this change, my above stress-test in our production system won't cause deadlock any more. I also implemented a scale-down version of reproducer in the selftest (a subsequent commit). With latest bpf-next, it complains for the following potential deadlock. [ 32.832450] -> #1 (&p->pi_lock){-.-.}: [ 32.833100] _raw_spin_lock_irqsave+0x44/0x80 [ 32.833696] task_rq_lock+0x2c/0xa0 [ 32.834182] task_sched_runtime+0x59/0xd0 [ 32.834721] thread_group_cputime+0x250/0x270 [ 32.835304] thread_group_cputime_adjusted+0x2e/0x70 [ 32.835959] do_task_stat+0x8a7/0xb80 [ 32.836461] proc_single_show+0x51/0xb0 ... [ 32.839512] -> #0 (&(&sighand->siglock)->rlock){....}: [ 32.840275] __lock_acquire+0x1358/0x1a20 [ 32.840826] lock_acquire+0xc7/0x1d0 [ 32.841309] _raw_spin_lock_irqsave+0x44/0x80 [ 32.841916] __lock_task_sighand+0x79/0x160 [ 32.842465] do_send_sig_info+0x35/0x90 [ 32.842977] bpf_send_signal+0xa/0x10 [ 32.843464] bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000 [ 32.844301] trace_call_bpf+0x115/0x270 [ 32.844809] perf_trace_run_bpf_submit+0x4a/0xc0 [ 32.845411] perf_trace_sched_switch+0x10f/0x180 [ 32.846014] __schedule+0x45d/0x880 [ 32.846483] schedule+0x5f/0xd0 ... [ 32.853148] Chain exists of: [ 32.853148] &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock [ 32.853148] [ 32.854451] Possible unsafe locking scenario: [ 32.854451] [ 32.855173] CPU0 CPU1 [ 32.855745] ---- ---- [ 32.856278] lock(&rq->lock); [ 32.856671] lock(&p->pi_lock); [ 32.857332] lock(&rq->lock); [ 32.857999] lock(&(&sighand->siglock)->rlock); Deadlock happens on CPU0 when it tries to acquire &sighand->siglock but it has been held by CPU1 and CPU1 tries to grab &rq->lock and cannot get it. This is not exactly the callstack in our production environment, but sympotom is similar and both locks are using spin_lock_irqsave() to acquire the lock, and both involves rq_lock. The fix to delay sending signal when irq is disabled also fixed this issue. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com

When mmap2 events are synthesized the ino_generation field isn't being set leading to uninitialized memory being compared. Caught with clang's -fsanitize=memory: ==124733==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x55a96a6a65cc in __dso_id__cmp tools/perf/util/dsos.c:23:6 #1 0x55a96a6a81d5 in dso_id__cmp tools/perf/util/dsos.c:38:9 #2 0x55a96a6a717f in __dso__cmp_long_name tools/perf/util/dsos.c:74:15 #3 0x55a96a6a6c4c in __dsos__findnew_link_by_longname_id tools/perf/util/dsos.c:106:12 #4 0x55a96a6a851e in __dsos__findnew_by_longname_id tools/perf/util/dsos.c:178:9 #5 0x55a96a6a7798 in __dsos__find_id tools/perf/util/dsos.c:191:9 #6 0x55a96a6a7b57 in __dsos__findnew_id tools/perf/util/dsos.c:251:20 #7 0x55a96a6a7a57 in dsos__findnew_id tools/perf/util/dsos.c:259:17 #8 0x55a96a7776ae in machine__findnew_dso_id tools/perf/util/machine.c:2709:9 #9 0x55a96a77dfcf in map__new tools/perf/util/map.c:193:10 #10 0x55a96a77240a in machine__process_mmap2_event tools/perf/util/machine.c:1670:8 #11 0x55a96a7741a3 in machine__process_event tools/perf/util/machine.c:1882:9 #12 0x55a96a6aee39 in perf_event__process tools/perf/util/event.c:454:9 #13 0x55a96a87d633 in perf_tool__process_synth_event tools/perf/util/synthetic-events.c:63:9 #14 0x55a96a87f131 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:403:7 #15 0x55a96a8815d6 in __event__synthesize_thread tools/perf/util/synthetic-events.c:548:9 #16 0x55a96a882bff in __perf_event__synthesize_threads tools/perf/util/synthetic-events.c:681:3 #17 0x55a96a881ec2 in perf_event__synthesize_threads tools/perf/util/synthetic-events.c:750:9 #18 0x55a96a562b26 in synth_all tools/perf/tests/mmap-thread-lookup.c:136:9 #19 0x55a96a5623b1 in mmap_events tools/perf/tests/mmap-thread-lookup.c:174:8 #20 0x55a96a561fa0 in test__mmap_thread_lookup tools/perf/tests/mmap-thread-lookup.c:230:2 #21 0x55a96a52c182 in run_test tools/perf/tests/builtin-test.c:378:9 #22 0x55a96a52afc1 in test_and_print tools/perf/tests/builtin-test.c:408:9 #23 0x55a96a52966e in __cmd_test tools/perf/tests/builtin-test.c:603:4 #24 0x55a96a52855d in cmd_test tools/perf/tests/builtin-test.c:747:9 #25 0x55a96a2844d4 in run_builtin tools/perf/perf.c:312:11 #26 0x55a96a282bd0 in handle_internal_command tools/perf/perf.c:364:8 #27 0x55a96a284097 in run_argv tools/perf/perf.c:408:2 #28 0x55a96a282223 in main tools/perf/perf.c:538:3 Uninitialized value was stored to memory at #1 0x55a96a6a18f7 in dso__new_id tools/perf/util/dso.c:1230:14 #2 0x55a96a6a78ee in __dsos__addnew_id tools/perf/util/dsos.c:233:20 #3 0x55a96a6a7bcc in __dsos__findnew_id tools/perf/util/dsos.c:252:21 #4 0x55a96a6a7a57 in dsos__findnew_id tools/perf/util/dsos.c:259:17 #5 0x55a96a7776ae in machine__findnew_dso_id tools/perf/util/machine.c:2709:9 #6 0x55a96a77dfcf in map__new tools/perf/util/map.c:193:10 #7 0x55a96a77240a in machine__process_mmap2_event tools/perf/util/machine.c:1670:8 #8 0x55a96a7741a3 in machine__process_event tools/perf/util/machine.c:1882:9 #9 0x55a96a6aee39 in perf_event__process tools/perf/util/event.c:454:9 #10 0x55a96a87d633 in perf_tool__process_synth_event tools/perf/util/synthetic-events.c:63:9 #11 0x55a96a87f131 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:403:7 #12 0x55a96a8815d6 in __event__synthesize_thread tools/perf/util/synthetic-events.c:548:9 #13 0x55a96a882bff in __perf_event__synthesize_threads tools/perf/util/synthetic-events.c:681:3 #14 0x55a96a881ec2 in perf_event__synthesize_threads tools/perf/util/synthetic-events.c:750:9 #15 0x55a96a562b26 in synth_all tools/perf/tests/mmap-thread-lookup.c:136:9 #16 0x55a96a5623b1 in mmap_events tools/perf/tests/mmap-thread-lookup.c:174:8 #17 0x55a96a561fa0 in test__mmap_thread_lookup tools/perf/tests/mmap-thread-lookup.c:230:2 #18 0x55a96a52c182 in run_test tools/perf/tests/builtin-test.c:378:9 #19 0x55a96a52afc1 in test_and_print tools/perf/tests/builtin-test.c:408:9 Uninitialized value was stored to memory at #0 0x55a96a7725af in machine__process_mmap2_event tools/perf/util/machine.c:1646:25 #1 0x55a96a7741a3 in machine__process_event tools/perf/util/machine.c:1882:9 #2 0x55a96a6aee39 in perf_event__process tools/perf/util/event.c:454:9 #3 0x55a96a87d633 in perf_tool__process_synth_event tools/perf/util/synthetic-events.c:63:9 #4 0x55a96a87f131 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:403:7 #5 0x55a96a8815d6 in __event__synthesize_thread tools/perf/util/synthetic-events.c:548:9 #6 0x55a96a882bff in __perf_event__synthesize_threads tools/perf/util/synthetic-events.c:681:3 #7 0x55a96a881ec2 in perf_event__synthesize_threads tools/perf/util/synthetic-events.c:750:9 #8 0x55a96a562b26 in synth_all tools/perf/tests/mmap-thread-lookup.c:136:9 #9 0x55a96a5623b1 in mmap_events tools/perf/tests/mmap-thread-lookup.c:174:8 #10 0x55a96a561fa0 in test__mmap_thread_lookup tools/perf/tests/mmap-thread-lookup.c:230:2 #11 0x55a96a52c182 in run_test tools/perf/tests/builtin-test.c:378:9 #12 0x55a96a52afc1 in test_and_print tools/perf/tests/builtin-test.c:408:9 #13 0x55a96a52966e in __cmd_test tools/perf/tests/builtin-test.c:603:4 #14 0x55a96a52855d in cmd_test tools/perf/tests/builtin-test.c:747:9 #15 0x55a96a2844d4 in run_builtin tools/perf/perf.c:312:11 #16 0x55a96a282bd0 in handle_internal_command tools/perf/perf.c:364:8 #17 0x55a96a284097 in run_argv tools/perf/perf.c:408:2 #18 0x55a96a282223 in main tools/perf/perf.c:538:3 Uninitialized value was created by a heap allocation #0 0x55a96a22f60d in malloc llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:925:3 #1 0x55a96a882948 in __perf_event__synthesize_threads tools/perf/util/synthetic-events.c:655:15 #2 0x55a96a881ec2 in perf_event__synthesize_threads tools/perf/util/synthetic-events.c:750:9 #3 0x55a96a562b26 in synth_all tools/perf/tests/mmap-thread-lookup.c:136:9 #4 0x55a96a5623b1 in mmap_events tools/perf/tests/mmap-thread-lookup.c:174:8 #5 0x55a96a561fa0 in test__mmap_thread_lookup tools/perf/tests/mmap-thread-lookup.c:230:2 #6 0x55a96a52c182 in run_test tools/perf/tests/builtin-test.c:378:9 #7 0x55a96a52afc1 in test_and_print tools/perf/tests/builtin-test.c:408:9 #8 0x55a96a52966e in __cmd_test tools/perf/tests/builtin-test.c:603:4 #9 0x55a96a52855d in cmd_test tools/perf/tests/builtin-test.c:747:9 #10 0x55a96a2844d4 in run_builtin tools/perf/perf.c:312:11 #11 0x55a96a282bd0 in handle_internal_command tools/perf/perf.c:364:8 #12 0x55a96a284097 in run_argv tools/perf/perf.c:408:2 #13 0x55a96a282223 in main tools/perf/perf.c:538:3 SUMMARY: MemorySanitizer: use-of-uninitialized-value tools/perf/util/dsos.c:23:6 in __dso_id__cmp Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: clang-built-linux@googlegroups.com Link: http://lore.kernel.org/lkml/20200313053129.131264-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The following was observed by Kar Hin Ong with RT patchset: Backtrace: irq 19: nobody cared (try booting with the "irqpoll" option) CPU: 0 PID: 3329 Comm: irq/34-nipalk Tainted:4.14.87-rt49 #1 Hardware name: National Instruments NI PXIe-8880/NI PXIe-8880, BIOS 2.1.5f1 01/09/2020 Call Trace: <IRQ> ? dump_stack+0x46/0x5e ? __report_bad_irq+0x2e/0xb0 ? note_interrupt+0x242/0x290 ? nNIKAL100_memoryRead16+0x8/0x10 [nikal] ? handle_irq_event_percpu+0x55/0x70 ? handle_irq_event+0x4f/0x80 ? handle_fasteoi_irq+0x81/0x180 ? handle_irq+0x1c/0x30 ? do_IRQ+0x41/0xd0 ? common_interrupt+0x84/0x84 </IRQ> ... handlers: [<ffffffffb3297200>] irq_default_primary_handler threaded [<ffffffffb3669180>] usb_hcd_irq Disabling IRQ #19 The problem being that this device is triggering boot interrupts due to threaded interrupt handling and masking of the IO-APIC. These boot interrupts are then forwarded on to the legacy PCH's PIRQ lines where there is no handler present for the device. Whenever a PCI device fires interrupt (INTx) to Pin 20 of IOAPIC 2 (GSI 44), the kernel receives two interrupts: 1. Interrupt from Pin 20 of IOAPIC 2 -> Expected 2. Interrupt from Pin 19 of IOAPIC 1 -> UNEXPECTED Quirks for disabling boot interrupts (preferred) or rerouting the handler exist but do not address these Xeon chipsets' mechanism: https://lore.kernel.org/lkml/12131949181903-git-send-email-sassmann@suse.de/ Add a new mechanism via PCI CFG for those chipsets supporting CIPINTRC register's dis_intx_rout2ich bit. Link: https://lore.kernel.org/r/20200220192930.64820-2-sean.v.kelley@linux.intel.com Reported-by: Kar Hin Ong <kar.hin.ong@ni.com> Tested-by: Kar Hin Ong <kar.hin.ong@ni.com> Signed-off-by: Sean V Kelley <sean.v.kelley@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org

I compiled with AddressSanitizer and I had these memory leaks while I was using the tep_parse_format function: Direct leak of 28 byte(s) in 4 object(s) allocated from: #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe) #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985 #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140 #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206 #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291 #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299 #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849 #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161 #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207 #9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786 #10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285 #11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369 #12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335 #13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389 #14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431 #15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251 #16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284 #17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593 #18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727 #19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048 #20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127 #21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152 #22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252 #23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347 #24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461 #25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673 #26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2) The token variable in the process_dynamic_array_len function is allocated in the read_expect_type function, but is not freed before calling the read_token function. Free the token variable before calling read_token in order to plug the leak. Signed-off-by: Philippe Duplessis-Guindon <pduplessis@efficios.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The following deadlock was captured. The first process is holding 'kernfs_mutex' and hung by io. The io was staging in 'r1conf.pending_bio_list' of raid1 device, this pending bio list would be flushed by second process 'md127_raid1', but it was hung by 'kernfs_mutex'. Using sysfs_notify_dirent_safe() to replace sysfs_notify() can fix it. There were other sysfs_notify() invoked from io path, removed all of them. PID: 40430 TASK: ffff8ee9c8c65c40 CPU: 29 COMMAND: "probe_file" #0 [ffffb87c4df37260] __schedule at ffffffff9a8678ec #1 [ffffb87c4df372f8] schedule at ffffffff9a867f06 #2 [ffffb87c4df37310] io_schedule at ffffffff9a0c73e6 #3 [ffffb87c4df37328] __dta___xfs_iunpin_wait_3443 at ffffffffc03a4057 [xfs] #4 [ffffb87c4df373a0] xfs_iunpin_wait at ffffffffc03a6c79 [xfs] #5 [ffffb87c4df373b0] __dta_xfs_reclaim_inode_3357 at ffffffffc039a46c [xfs] #6 [ffffb87c4df37400] xfs_reclaim_inodes_ag at ffffffffc039a8b6 [xfs] #7 [ffffb87c4df37590] xfs_reclaim_inodes_nr at ffffffffc039bb33 [xfs] #8 [ffffb87c4df375b0] xfs_fs_free_cached_objects at ffffffffc03af0e9 [xfs] #9 [ffffb87c4df375c0] super_cache_scan at ffffffff9a287ec7 #10 [ffffb87c4df37618] shrink_slab at ffffffff9a1efd93 #11 [ffffb87c4df37700] shrink_node at ffffffff9a1f5968 #12 [ffffb87c4df37788] do_try_to_free_pages at ffffffff9a1f5ea2 #13 [ffffb87c4df377f0] try_to_free_mem_cgroup_pages at ffffffff9a1f6445 #14 [ffffb87c4df37880] try_charge at ffffffff9a26cc5f #15 [ffffb87c4df37920] memcg_kmem_charge_memcg at ffffffff9a270f6a #16 [ffffb87c4df37958] new_slab at ffffffff9a251430 #17 [ffffb87c4df379c0] ___slab_alloc at ffffffff9a251c85 #18 [ffffb87c4df37a80] __slab_alloc at ffffffff9a25635d #19 [ffffb87c4df37ac0] kmem_cache_alloc at ffffffff9a251f89 #20 [ffffb87c4df37b00] alloc_inode at ffffffff9a2a2b10 #21 [ffffb87c4df37b20] iget_locked at ffffffff9a2a4854 #22 [ffffb87c4df37b60] kernfs_get_inode at ffffffff9a311377 #23 [ffffb87c4df37b80] kernfs_iop_lookup at ffffffff9a311e2b #24 [ffffb87c4df37ba8] lookup_slow at ffffffff9a290118 #25 [ffffb87c4df37c10] walk_component at ffffffff9a291e83 #26 [ffffb87c4df37c78] path_lookupat at ffffffff9a293619 #27 [ffffb87c4df37cd8] filename_lookup at ffffffff9a2953af #28 [ffffb87c4df37de8] user_path_at_empty at ffffffff9a295566 #29 [ffffb87c4df37e10] vfs_statx at ffffffff9a289787 #30 [ffffb87c4df37e70] SYSC_newlstat at ffffffff9a289d5d #31 [ffffb87c4df37f18] sys_newlstat at ffffffff9a28a60e #32 [ffffb87c4df37f28] do_syscall_64 at ffffffff9a003949 #33 [ffffb87c4df37f50] entry_SYSCALL_64_after_hwframe at ffffffff9aa001ad RIP: 00007f617a5f2905 RSP: 00007f607334f838 RFLAGS: 00000246 RAX: ffffffffffffffda RBX: 00007f6064044b20 RCX: 00007f617a5f2905 RDX: 00007f6064044b20 RSI: 00007f6064044b20 RDI: 00007f6064005890 RBP: 00007f6064044aa0 R8: 0000000000000030 R9: 000000000000011c R10: 0000000000000013 R11: 0000000000000246 R12: 00007f606417e6d0 R13: 00007f6064044aa0 R14: 00007f6064044b10 R15: 00000000ffffffff ORIG_RAX: 0000000000000006 CS: 0033 SS: 002b PID: 927 TASK: ffff8f15ac5dbd80 CPU: 42 COMMAND: "md127_raid1" #0 [ffffb87c4df07b28] __schedule at ffffffff9a8678ec #1 [ffffb87c4df07bc0] schedule at ffffffff9a867f06 #2 [ffffb87c4df07bd8] schedule_preempt_disabled at ffffffff9a86825e #3 [ffffb87c4df07be8] __mutex_lock at ffffffff9a869bcc #4 [ffffb87c4df07ca0] __mutex_lock_slowpath at ffffffff9a86a013 #5 [ffffb87c4df07cb0] mutex_lock at ffffffff9a86a04f #6 [ffffb87c4df07cc8] kernfs_find_and_get_ns at ffffffff9a311d83 #7 [ffffb87c4df07cf0] sysfs_notify at ffffffff9a314b3a #8 [ffffb87c4df07d18] md_update_sb at ffffffff9a688696 #9 [ffffb87c4df07d98] md_update_sb at ffffffff9a6886d5 #10 [ffffb87c4df07da8] md_check_recovery at ffffffff9a68ad9c #11 [ffffb87c4df07dd0] raid1d at ffffffffc01f0375 [raid1] #12 [ffffb87c4df07ea0] md_thread at ffffffff9a680348 #13 [ffffb87c4df07f08] kthread at ffffffff9a0b8005 #14 [ffffb87c4df07f50] ret_from_fork at ffffffff9aa00344 Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by: Song Liu <songliubraving@fb.com>

This patch is to fix a crash: #3 [ffffb6580689f898] oops_end at ffffffffa2835bc2 #4 [ffffb6580689f8b8] no_context at ffffffffa28766e7 #5 [ffffb6580689f920] async_page_fault at ffffffffa320135e [exception RIP: f2fs_is_compressed_page+34] RIP: ffffffffa2ba83a2 RSP: ffffb6580689f9d8 RFLAGS: 00010213 RAX: 0000000000000001 RBX: fffffc0f50b34bc0 RCX: 0000000000002122 RDX: 0000000000002123 RSI: 0000000000000c00 RDI: fffffc0f50b34bc0 RBP: ffff97e815a40178 R8: 0000000000000000 R9: ffff97e83ffc9000 R10: 0000000000032300 R11: 0000000000032380 R12: ffffb6580689fa38 R13: fffffc0f50b34bc0 R14: ffff97e825cbd000 R15: 0000000000000c00 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffffb6580689f9d8] __is_cp_guaranteed at ffffffffa2b7ea98 #7 [ffffb6580689f9f0] f2fs_submit_page_write at ffffffffa2b81a69 #8 [ffffb6580689fa30] f2fs_do_write_meta_page at ffffffffa2b99777 #9 [ffffb6580689fae0] __f2fs_write_meta_page at ffffffffa2b75f1a #10 [ffffb6580689fb18] f2fs_sync_meta_pages at ffffffffa2b77466 #11 [ffffb6580689fc98] do_checkpoint at ffffffffa2b78e46 #12 [ffffb6580689fd88] f2fs_write_checkpoint at ffffffffa2b79c29 #13 [ffffb6580689fdd0] f2fs_sync_fs at ffffffffa2b69d95 #14 [ffffb6580689fe20] sync_filesystem at ffffffffa2ad2574 #15 [ffffb6580689fe30] generic_shutdown_super at ffffffffa2a9b582 #16 [ffffb6580689fe48] kill_block_super at ffffffffa2a9b6d1 #17 [ffffb6580689fe60] kill_f2fs_super at ffffffffa2b6abe1 #18 [ffffb6580689fea0] deactivate_locked_super at ffffffffa2a9afb6 #19 [ffffb6580689feb8] cleanup_mnt at ffffffffa2abcad4 #20 [ffffb6580689fee0] task_work_run at ffffffffa28bca28 #21 [ffffb6580689ff00] exit_to_usermode_loop at ffffffffa28050b7 #22 [ffffb6580689ff38] do_syscall_64 at ffffffffa280560e #23 [ffffb6580689ff50] entry_SYSCALL_64_after_hwframe at ffffffffa320008c This occurred when umount f2fs if enable F2FS_FS_COMPRESSION with F2FS_IO_TRACE. Fixes it by adding IS_IO_TRACED_PAGE to check validity of pid for page_private. Signed-off-by: Yu Changchun <yuchangchun1@huawei.com> Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The test_generic_metric() missed to release entries in the pctx. Asan reported following leak (and more): Direct leak of 128 byte(s) in 1 object(s) allocated from: #0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) #1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14) #2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497) #3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111 #4 0x55f7e7341667 in expr__add_ref util/expr.c:120 #5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783 #6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858 #7 0x55f7e712390b in compute_single tests/parse-metric.c:128 #8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180 #9 0x55f7e712446d in compute_metric tests/parse-metric.c:196 #10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295 #11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355 #12 0x55f7e70be09b in run_test tests/builtin-test.c:410 #13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440 #14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661 #15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807 #16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 #17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 #18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 #19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 #20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: 6d432c4 ("perf tools: Add test_generic_metric function") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-8-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The metricgroup__add_metric() can find multiple match for a metric group and it's possible to fail. Also it can fail in the middle like in resolve_metric() even for single metric. In those cases, the intermediate list and ids will be leaked like: Direct leak of 3 byte(s) in 1 object(s) allocated from: #0 0x7f4c938f40b5 in strdup (/lib/x86_64-linux-gnu/libasan.so.5+0x920b5) #1 0x55f7e71c1bef in __add_metric util/metricgroup.c:683 #2 0x55f7e71c31d0 in add_metric util/metricgroup.c:906 #3 0x55f7e71c3844 in metricgroup__add_metric util/metricgroup.c:940 #4 0x55f7e71c488d in metricgroup__add_metric_list util/metricgroup.c:993 #5 0x55f7e71c488d in parse_groups util/metricgroup.c:1045 #6 0x55f7e71c60a4 in metricgroup__parse_groups_test util/metricgroup.c:1087 #7 0x55f7e71235ae in __compute_metric tests/parse-metric.c:164 #8 0x55f7e7124650 in compute_metric tests/parse-metric.c:196 #9 0x55f7e7124650 in test_recursion_fail tests/parse-metric.c:318 #10 0x55f7e7124650 in test__parse_metric tests/parse-metric.c:356 #11 0x55f7e70be09b in run_test tests/builtin-test.c:410 #12 0x55f7e70be09b in test_and_print tests/builtin-test.c:440 #13 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661 #14 0x55f7e70c101a in cmd_test tests/builtin-test.c:807 #15 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 #16 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 #17 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 #18 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 #19 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: 83de0b7 ("perf metric: Collect referenced metrics in struct metric_ref_node") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-9-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

We have some really ancient debug printouts in the x86 boot image build code: Setup is 14108 bytes (padded to 14336 bytes). System is 8802 kB CRC 27e909d4 None of these ever helped debug any sort of breakage that I know of, and they clutter the build output. Remove them - if anyone needs the see the various interim stages of this to debug an obscure bug, they can add these printfs and more. We still keep this one: Kernel: arch/x86/boot/bzImage is ready (#19) As a sentimental leftover, plus the '#19' build count tag is mildly useful. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: linux-kernel@vger.kernel.org Cc: x86@kernel.org

Like evlist cpu map, evsel's cpu map should have a proper refcount. As it's created with a refcount, we don't need to get an extra count. Thanks to Arnaldo for the simpler suggestion. This, together with the following patch, fixes the following ASAN report: Direct leak of 840 byte(s) in 70 object(s) allocated from: #0 0x7fe36703f628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628) #1 0x559fbbf611ca in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79 #2 0x559fbbf6229c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237 #3 0x559fbbcc6c6d in __add_event util/parse-events.c:357 #4 0x559fbbcc6c6d in add_event_tool util/parse-events.c:408 #5 0x559fbbcc6c6d in parse_events_add_tool util/parse-events.c:1414 #6 0x559fbbd8474d in parse_events_parse util/parse-events.y:439 #7 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096 #8 0x559fbbcc95da in __parse_events util/parse-events.c:2141 #9 0x559fbbc2788b in check_parse_id tests/pmu-events.c:406 #10 0x559fbbc2788b in check_parse_id tests/pmu-events.c:393 #11 0x559fbbc2788b in check_parse_fake tests/pmu-events.c:436 #12 0x559fbbc2788b in metric_parse_fake tests/pmu-events.c:553 #13 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:599 #14 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:574 #15 0x559fbbc0109b in run_test tests/builtin-test.c:410 #16 0x559fbbc0109b in test_and_print tests/builtin-test.c:440 #17 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695 #18 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807 #19 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 #20 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 #21 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 #22 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 #23 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308 And I've failed which commit introduced this bug as the code was heavily changed since then. ;-/ Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200917060219.1287863-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Commit 4d00409 ("lockdep: Fix lockdep recursion") uncovered the following issue in lib/crc32test reported on s390: BUG: using __this_cpu_read() in preemptible [00000000] code: swapper/0/1 caller is lockdep_hardirqs_on_prepare+0x48/0x270 CPU: 6 PID: 1 Comm: swapper/0 Not tainted 5.9.0-next-20201015-15164-g03d992bd2de6 #19 Hardware name: IBM 3906 M04 704 (LPAR) Call Trace: lockdep_hardirqs_on_prepare+0x48/0x270 trace_hardirqs_on+0x9c/0x1b8 crc32_test.isra.0+0x170/0x1c0 crc32test_init+0x1c/0x40 do_one_initcall+0x40/0x130 do_initcalls+0x126/0x150 kernel_init_freeable+0x1f6/0x230 kernel_init+0x22/0x150 ret_from_fork+0x24/0x2c no locks held by swapper/0/1. Remove extra local_irq_disable/local_irq_enable helpers calls. Fixes: 5fb7f87 ("lib: add module support to crc32 tests") Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lkml.kernel.org/r/patch.git-4369da00c06e.your-ad-here.call-01602859837-ext-1679@work.hours Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This fix is for a failure that occurred in the DWARF unwind perf test. Stack unwinders may probe memory when looking for frames. Memory sanitizer will poison and track uninitialized memory on the stack, and on the heap if the value is copied to the heap. This can lead to false memory sanitizer failures for the use of an uninitialized value. Avoid this problem by removing the poison on the copied stack. The full msan failure with track origins looks like: ==2168==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x559ceb10755b in handle_cfi elfutils/libdwfl/frame_unwind.c:648:8 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106acf in __libdwfl_frame_reg_set elfutils/libdwfl/frame_unwind.c:77:22 #1 0x559ceb106acf in handle_cfi elfutils/libdwfl/frame_unwind.c:627:13 #2 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #3 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #4 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #5 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #6 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #7 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #8 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #9 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #10 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #11 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #12 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #13 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #14 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #15 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #16 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #17 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #18 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #19 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #20 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #21 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #22 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #23 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #24 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106a54 in handle_cfi elfutils/libdwfl/frame_unwind.c:613:9 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceaff8800 in memory_read tools/perf/util/unwind-libdw.c:156:10 #1 0x559ceb10f053 in expr_eval elfutils/libdwfl/frame_unwind.c:501:13 #2 0x559ceb1060cc in handle_cfi elfutils/libdwfl/frame_unwind.c:603:18 #3 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #4 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #5 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #6 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #7 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #8 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #9 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #10 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #11 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #12 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #13 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #14 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #15 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #16 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #17 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #18 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #19 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #20 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #21 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #22 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #23 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #24 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #25 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559cea9027d9 in __msan_memcpy llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3 #1 0x559cea9d2185 in sample_ustack tools/perf/arch/x86/tests/dwarf-unwind.c:41:2 #2 0x559cea9d202c in test__arch_unwind_sample tools/perf/arch/x86/tests/dwarf-unwind.c:72:9 #3 0x559ceabc9cbd in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:106:6 #4 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #5 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #6 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #7 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #8 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #9 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #10 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #11 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #12 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #13 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #14 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #15 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #16 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #17 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was created by an allocation of 'bf' in the stack frame of function 'perf_event__synthesize_mmap_events' #0 0x559ceafc5f60 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:445 SUMMARY: MemorySanitizer: use-of-uninitialized-value elfutils/libdwfl/frame_unwind.c:648:8 in handle_cfi Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: clang-built-linux@googlegroups.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sandeep Dasgupta <sdasgup@google.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20201113182053.754625-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

nickdesaulniers added the [BUG] llvm A bug that should be fixed in upstream LLVM label May 11, 2018

nickdesaulniers added the [PATCH] Exists There is a patch that fixes this issue label Jun 2, 2018

nickdesaulniers assigned niravhdave Jun 5, 2018

nickdesaulniers added this to the clang-7 milestone Jun 7, 2018

nickdesaulniers closed this as completed Jun 7, 2018

nickdesaulniers added the [ARCH] x86_64 This bug impacts ARCH=x86_64 label Aug 17, 2018

nickdesaulniers added the [FIXED][LLVM] 7 This bug was fixed in LLVM 7.0 label Sep 24, 2018

tpimh removed the [PATCH] Exists There is a patch that fixes this issue label Sep 25, 2018

stephenhines mentioned this issue Feb 21, 2020

Assertion `!isa<CallBrInst>(Preds[i]->getTerminator()) && "Cannot split an edge from a CallBrInst"' failed. #896

Closed

jcai19 mentioned this issue Mar 11, 2020

arch/x86/entry/entry_64_compat.S: Assertion `OS.tell() - Start == Layout.getSectionAddressSize(Sec)' failed #929

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nickdesaulniers mentioned this issue Oct 20, 2020

Assertion `BitWidth == RHS.BitWidth && "Comparison requires equal bit widths"' failed #1183

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arndb mentioned this issue Mar 6, 2021

thinlto: Crash during final link #1322

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pkm774 mentioned this issue Jun 4, 2021

invalid operand for umov #1392

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ms178 mentioned this issue Sep 20, 2021

Clang Full LTO broken on Linux 5.14.6 with LLVM/Clang 14-git 84b07c9b #1460

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ViNi-Arco mentioned this issue Mar 18, 2024

Erro module 'fs/jbd2/commit.o' on function '@jbd2_submit_inode_data' #2008

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integrated assembler does not support variable assignment #19

integrated assembler does not support variable assignment #19

nickdesaulniers commented May 11, 2018 •

edited

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nickdesaulniers commented May 11, 2018 •

edited by nathanchance

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nickdesaulniers commented May 11, 2018

nickdesaulniers commented Jun 7, 2018 •

edited by nathanchance

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nickdesaulniers commented Jun 7, 2018

integrated assembler does not support variable assignment #19

integrated assembler does not support variable assignment #19

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nickdesaulniers commented May 11, 2018 •

edited

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nickdesaulniers commented May 11, 2018 •

edited by nathanchance

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nickdesaulniers commented Jun 7, 2018 •

edited by nathanchance

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