Add futex support to LKL. #2
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This uses the GCC builtins for the atomic ops, avoiding architecture-specific code.
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SeanTAllen
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commit fde9f39 upstream. This patch fixes a race condition that causes a use-after-free during amdgpu_dm_atomic_commit_tail. This can occur when 2 non-blocking commits are requested and the second one finishes before the first. Essentially, this bug occurs when the following sequence of events happens: 1. Non-blocking commit #1 is requested w/ a new dm_state #1 and is deferred to the workqueue. 2. Non-blocking commit #2 is requested w/ a new dm_state #2 and is deferred to the workqueue. 3. Commit #2 starts before commit #1, dm_state #1 is used in the commit_tail and commit #2 completes, freeing dm_state #1. 4. Commit #1 starts after commit #2 completes, uses the freed dm_state 1 and dereferences a freelist pointer while setting the context. Since this bug has only been spotted with fast commits, this patch fixes the bug by clearing the dm_state instead of using the old dc_state for fast updates. In addition, since dm_state is only used for its dc_state and amdgpu_dm_atomic_commit_tail will retain the dc_state if none is found, removing the dm_state should not have any consequences in fast updates. This use-after-free bug has existed for a while now, but only caused a noticeable issue starting from 5.7-rc1 due to 3202fa6 ("slub: relocate freelist pointer to middle of object") moving the freelist pointer from dm_state->base (which was unused) to dm_state->context (which is dereferenced). Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207383 Fixes: bd200d1 ("drm/amd/display: Don't replace the dc_state for fast updates") Reported-by: Duncan <1i5t5.duncan@cox.net> Signed-off-by: Mazin Rezk <mnrzk@protonmail.com> Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit e24c644 ] 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 lkl#11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369 lkl#12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335 lkl#13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389 lkl#14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431 lkl#15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251 lkl#16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284 lkl#17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593 lkl#18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727 lkl#19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048 lkl#20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127 lkl#21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152 lkl#22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252 lkl#23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347 lkl#24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461 lkl#25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673 lkl#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> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit e0f1a30 ] When, at probe time, an SCMI communication failure inhibits the capacity to query power domains states, such domains should be skipped. Registering partially initialized SCMI power domains with genpd will causes kernel panic. arm-scmi timed out in resp(caller: scmi_power_state_get+0xa4/0xd0) scmi-power-domain scmi_dev.2: failed to get state for domain 9 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000009f3691000 [0000000000000000] pgd=00000009f1ca0003, p4d=00000009f1ca0003, pud=00000009f35ea003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP CPU: 2 PID: 381 Comm: bash Not tainted 5.8.0-rc1-00011-gebd118c2cca8 #2 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Jan 3 2020 Internal error: Oops: 96000006 [#1] PREEMPT SMP pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--) pc : of_genpd_add_provider_onecell+0x98/0x1f8 lr : of_genpd_add_provider_onecell+0x48/0x1f8 Call trace: of_genpd_add_provider_onecell+0x98/0x1f8 scmi_pm_domain_probe+0x174/0x1e8 scmi_dev_probe+0x90/0xe0 really_probe+0xe4/0x448 driver_probe_device+0xfc/0x168 device_driver_attach+0x7c/0x88 bind_store+0xe8/0x128 drv_attr_store+0x2c/0x40 sysfs_kf_write+0x4c/0x60 kernfs_fop_write+0x114/0x230 __vfs_write+0x24/0x50 vfs_write+0xbc/0x1e0 ksys_write+0x70/0xf8 __arm64_sys_write+0x24/0x30 el0_svc_common.constprop.3+0x94/0x160 do_el0_svc+0x2c/0x98 el0_sync_handler+0x148/0x1a8 el0_sync+0x158/0x180 Do not register any power domain that failed to be queried with genpd. Fixes: 898216c ("firmware: arm_scmi: add device power domain support using genpd") Link: https://lore.kernel.org/r/20200619220330.12217-1-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit ab0db04 ] When running with -o enospc_debug you can get the following splat if one of the dump_space_info's trip ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc5+ lkl#20 Tainted: G OE ------------------------------------------------------ dd/563090 is trying to acquire lock: ffff9e7dbf4f1e18 (&ctl->tree_lock){+.+.}-{2:2}, at: btrfs_dump_free_space+0x2b/0xa0 [btrfs] but task is already holding lock: ffff9e7e2284d428 (&cache->lock){+.+.}-{2:2}, at: btrfs_dump_space_info+0xaa/0x120 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&cache->lock){+.+.}-{2:2}: _raw_spin_lock+0x25/0x30 btrfs_add_reserved_bytes+0x3c/0x3c0 [btrfs] find_free_extent+0x7ef/0x13b0 [btrfs] btrfs_reserve_extent+0x9b/0x180 [btrfs] btrfs_alloc_tree_block+0xc1/0x340 [btrfs] alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs] __btrfs_cow_block+0x122/0x530 [btrfs] btrfs_cow_block+0x106/0x210 [btrfs] commit_cowonly_roots+0x55/0x300 [btrfs] btrfs_commit_transaction+0x4ed/0xac0 [btrfs] sync_filesystem+0x74/0x90 generic_shutdown_super+0x22/0x100 kill_anon_super+0x14/0x30 btrfs_kill_super+0x12/0x20 [btrfs] deactivate_locked_super+0x36/0x70 cleanup_mnt+0x104/0x160 task_work_run+0x5f/0x90 __prepare_exit_to_usermode+0x1bd/0x1c0 do_syscall_64+0x5e/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&space_info->lock){+.+.}-{2:2}: _raw_spin_lock+0x25/0x30 btrfs_block_rsv_release+0x1a6/0x3f0 [btrfs] btrfs_inode_rsv_release+0x4f/0x170 [btrfs] btrfs_clear_delalloc_extent+0x155/0x480 [btrfs] clear_state_bit+0x81/0x1a0 [btrfs] __clear_extent_bit+0x25c/0x5d0 [btrfs] clear_extent_bit+0x15/0x20 [btrfs] btrfs_invalidatepage+0x2b7/0x3c0 [btrfs] truncate_cleanup_page+0x47/0xe0 truncate_inode_pages_range+0x238/0x840 truncate_pagecache+0x44/0x60 btrfs_setattr+0x202/0x5e0 [btrfs] notify_change+0x33b/0x490 do_truncate+0x76/0xd0 path_openat+0x687/0xa10 do_filp_open+0x91/0x100 do_sys_openat2+0x215/0x2d0 do_sys_open+0x44/0x80 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&tree->lock#2){+.+.}-{2:2}: _raw_spin_lock+0x25/0x30 find_first_extent_bit+0x32/0x150 [btrfs] write_pinned_extent_entries.isra.0+0xc5/0x100 [btrfs] __btrfs_write_out_cache+0x172/0x480 [btrfs] btrfs_write_out_cache+0x7a/0xf0 [btrfs] btrfs_write_dirty_block_groups+0x286/0x3b0 [btrfs] commit_cowonly_roots+0x245/0x300 [btrfs] btrfs_commit_transaction+0x4ed/0xac0 [btrfs] close_ctree+0xf9/0x2f5 [btrfs] generic_shutdown_super+0x6c/0x100 kill_anon_super+0x14/0x30 btrfs_kill_super+0x12/0x20 [btrfs] deactivate_locked_super+0x36/0x70 cleanup_mnt+0x104/0x160 task_work_run+0x5f/0x90 __prepare_exit_to_usermode+0x1bd/0x1c0 do_syscall_64+0x5e/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&ctl->tree_lock){+.+.}-{2:2}: __lock_acquire+0x1240/0x2460 lock_acquire+0xab/0x360 _raw_spin_lock+0x25/0x30 btrfs_dump_free_space+0x2b/0xa0 [btrfs] btrfs_dump_space_info+0xf4/0x120 [btrfs] btrfs_reserve_extent+0x176/0x180 [btrfs] __btrfs_prealloc_file_range+0x145/0x550 [btrfs] cache_save_setup+0x28d/0x3b0 [btrfs] btrfs_start_dirty_block_groups+0x1fc/0x4f0 [btrfs] btrfs_commit_transaction+0xcc/0xac0 [btrfs] btrfs_alloc_data_chunk_ondemand+0x162/0x4c0 [btrfs] btrfs_check_data_free_space+0x4c/0xa0 [btrfs] btrfs_buffered_write.isra.0+0x19b/0x740 [btrfs] btrfs_file_write_iter+0x3cf/0x610 [btrfs] new_sync_write+0x11e/0x1b0 vfs_write+0x1c9/0x200 ksys_write+0x68/0xe0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Chain exists of: &ctl->tree_lock --> &space_info->lock --> &cache->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cache->lock); lock(&space_info->lock); lock(&cache->lock); lock(&ctl->tree_lock); *** DEADLOCK *** 6 locks held by dd/563090: #0: ffff9e7e21d18448 (sb_writers#14){.+.+}-{0:0}, at: vfs_write+0x195/0x200 #1: ffff9e7dd0410ed8 (&sb->s_type->i_mutex_key#19){++++}-{3:3}, at: btrfs_file_write_iter+0x86/0x610 [btrfs] #2: ffff9e7e21d18638 (sb_internal#2){.+.+}-{0:0}, at: start_transaction+0x40b/0x5b0 [btrfs] #3: ffff9e7e1f05d688 (&cur_trans->cache_write_mutex){+.+.}-{3:3}, at: btrfs_start_dirty_block_groups+0x158/0x4f0 [btrfs] #4: ffff9e7e2284ddb8 (&space_info->groups_sem){++++}-{3:3}, at: btrfs_dump_space_info+0x69/0x120 [btrfs] #5: ffff9e7e2284d428 (&cache->lock){+.+.}-{2:2}, at: btrfs_dump_space_info+0xaa/0x120 [btrfs] stack backtrace: CPU: 3 PID: 563090 Comm: dd Tainted: G OE 5.8.0-rc5+ lkl#20 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./890FX Deluxe5, BIOS P1.40 05/03/2011 Call Trace: dump_stack+0x96/0xd0 check_noncircular+0x162/0x180 __lock_acquire+0x1240/0x2460 ? wake_up_klogd.part.0+0x30/0x40 lock_acquire+0xab/0x360 ? btrfs_dump_free_space+0x2b/0xa0 [btrfs] _raw_spin_lock+0x25/0x30 ? btrfs_dump_free_space+0x2b/0xa0 [btrfs] btrfs_dump_free_space+0x2b/0xa0 [btrfs] btrfs_dump_space_info+0xf4/0x120 [btrfs] btrfs_reserve_extent+0x176/0x180 [btrfs] __btrfs_prealloc_file_range+0x145/0x550 [btrfs] ? btrfs_qgroup_reserve_data+0x1d/0x60 [btrfs] cache_save_setup+0x28d/0x3b0 [btrfs] btrfs_start_dirty_block_groups+0x1fc/0x4f0 [btrfs] btrfs_commit_transaction+0xcc/0xac0 [btrfs] ? start_transaction+0xe0/0x5b0 [btrfs] btrfs_alloc_data_chunk_ondemand+0x162/0x4c0 [btrfs] btrfs_check_data_free_space+0x4c/0xa0 [btrfs] btrfs_buffered_write.isra.0+0x19b/0x740 [btrfs] ? ktime_get_coarse_real_ts64+0xa8/0xd0 ? trace_hardirqs_on+0x1c/0xe0 btrfs_file_write_iter+0x3cf/0x610 [btrfs] new_sync_write+0x11e/0x1b0 vfs_write+0x1c9/0x200 ksys_write+0x68/0xe0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This is because we're holding the block_group->lock while trying to dump the free space cache. However we don't need this lock, we just need it to read the values for the printk, so move the free space cache dumping outside of the block group lock. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 6c4e9bc ] The WARN_*() macros are intended to catch impossible situations from the SW point of view. They gave a little in case HW<->SW interface is out-of-sync. Such out-of-sync scenario can be due to SW errors that are not part of this flow or because some HW errors, where dump stack won't help either. This specific WARN_ON() is useless because mlx5_core code is prepared to handle such situations and will unfold everything correctly while providing enough information to the users to understand why FS is not working. WARNING: CPU: 0 PID: 3222 at drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:825 connect_fts_in_prio.isra.20+0x1dd/0x260 linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:825 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 3222 Comm: syz-executor861 Not tainted 5.5.0-rc6+ #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack linux/lib/dump_stack.c:77 [inline] dump_stack+0x94/0xce linux/lib/dump_stack.c:118 panic+0x234/0x56f linux/kernel/panic.c:221 __warn+0x1cc/0x1e1 linux/kernel/panic.c:582 report_bug+0x200/0x310 linux/lib/bug.c:195 fixup_bug.part.11+0x32/0x80 linux/arch/x86/kernel/traps.c:174 fixup_bug linux/arch/x86/kernel/traps.c:273 [inline] do_error_trap+0xd3/0x100 linux/arch/x86/kernel/traps.c:267 do_invalid_op+0x31/0x40 linux/arch/x86/kernel/traps.c:286 invalid_op+0x1e/0x30 linux/arch/x86/entry/entry_64.S:1027 RIP: 0010:connect_fts_in_prio.isra.20+0x1dd/0x260 linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:825 Code: 00 00 48 c7 c2 60 8c 31 84 48 c7 c6 00 81 31 84 48 8b 38 e8 3c a8 cb ff 41 83 fd 01 8b 04 24 0f 8e 29 ff ff ff e8 83 7b bc fe <0f> 0b 8b 04 24 e9 1a ff ff ff 89 04 24 e8 c1 20 e0 fe 8b 04 24 eb RSP: 0018:ffffc90004bb7858 EFLAGS: 00010293 RAX: ffff88805de98e80 RBX: 0000000000000c96 RCX: ffffffff827a853d RDX: 0000000000000000 RSI: 0000000000000000 RDI: fffff52000976efa RBP: 0000000000000007 R08: ffffed100da060e3 R09: ffffed100da060e3 R10: 0000000000000001 R11: ffffed100da060e2 R12: dffffc0000000000 R13: 0000000000000002 R14: ffff8880683a1a10 R15: ffffed100d07bc1c connect_prev_fts linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:844 [inline] connect_flow_table linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:975 [inline] __mlx5_create_flow_table+0x8f8/0x1710 linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:1064 mlx5_create_flow_table linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:1094 [inline] mlx5_create_auto_grouped_flow_table+0xe1/0x210 linux/drivers/net/ethernet/mellanox/mlx5/core/fs_core.c:1136 _get_prio linux/drivers/infiniband/hw/mlx5/main.c:3286 [inline] get_flow_table+0x2ea/0x760 linux/drivers/infiniband/hw/mlx5/main.c:3376 mlx5_ib_create_flow+0x331/0x11c0 linux/drivers/infiniband/hw/mlx5/main.c:3896 ib_uverbs_ex_create_flow+0x13e8/0x1b40 linux/drivers/infiniband/core/uverbs_cmd.c:3311 ib_uverbs_write+0xaa5/0xdf0 linux/drivers/infiniband/core/uverbs_main.c:769 __vfs_write+0x7c/0x100 linux/fs/read_write.c:494 vfs_write+0x168/0x4a0 linux/fs/read_write.c:558 ksys_write+0xc8/0x200 linux/fs/read_write.c:611 do_syscall_64+0x9c/0x390 linux/arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45a059 Code: 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fcc17564c98 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fcc17564ca0 RCX: 000000000045a059 RDX: 0000000000000030 RSI: 00000000200003c0 RDI: 0000000000000005 RBP: 0000000000000007 R08: 0000000000000002 R09: 0000000000003131 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006e636c R13: 0000000000000000 R14: 00000000006e6360 R15: 00007ffdcbdaf6a0 Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 1 seconds.. Fixes: f90edfd ("net/mlx5_core: Connect flow tables") Reviewed-by: Maor Gottlieb <maorg@mellanox.com> Reviewed-by: Mark Bloch <markb@mellanox.com> Signed-off-by: Leon Romanovsky <leonro@mellanox.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 2dd2111 upstream. loop_rw_iter() does not check whether the file has a read or write function. This can lead to NULL pointer dereference when the user passes in a file descriptor that does not have read or write function. The crash log looks like this: [ 99.834071] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 99.835364] #PF: supervisor instruction fetch in kernel mode [ 99.836522] #PF: error_code(0x0010) - not-present page [ 99.837771] PGD 8000000079d62067 P4D 8000000079d62067 PUD 79d8c067 PMD 0 [ 99.839649] Oops: 0010 [#2] SMP PTI [ 99.840591] CPU: 1 PID: 333 Comm: io_wqe_worker-0 Tainted: G D 5.8.0 #2 [ 99.842622] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 [ 99.845140] RIP: 0010:0x0 [ 99.845840] Code: Bad RIP value. [ 99.846672] RSP: 0018:ffffa1c7c01ebc08 EFLAGS: 00010202 [ 99.848018] RAX: 0000000000000000 RBX: ffff92363bd67300 RCX: ffff92363d461208 [ 99.849854] RDX: 0000000000000010 RSI: 00007ffdbf696bb0 RDI: ffff92363bd67300 [ 99.851743] RBP: ffffa1c7c01ebc40 R08: 0000000000000000 R09: 0000000000000000 [ 99.853394] R10: ffffffff9ec692a0 R11: 0000000000000000 R12: 0000000000000010 [ 99.855148] R13: 0000000000000000 R14: ffff92363d461208 R15: ffffa1c7c01ebc68 [ 99.856914] FS: 0000000000000000(0000) GS:ffff92363dd00000(0000) knlGS:0000000000000000 [ 99.858651] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 99.860032] CR2: ffffffffffffffd6 CR3: 000000007ac66000 CR4: 00000000000006e0 [ 99.861979] Call Trace: [ 99.862617] loop_rw_iter.part.0+0xad/0x110 [ 99.863838] io_write+0x2ae/0x380 [ 99.864644] ? kvm_sched_clock_read+0x11/0x20 [ 99.865595] ? sched_clock+0x9/0x10 [ 99.866453] ? sched_clock_cpu+0x11/0xb0 [ 99.867326] ? newidle_balance+0x1d4/0x3c0 [ 99.868283] io_issue_sqe+0xd8f/0x1340 [ 99.869216] ? __switch_to+0x7f/0x450 [ 99.870280] ? __switch_to_asm+0x42/0x70 [ 99.871254] ? __switch_to_asm+0x36/0x70 [ 99.872133] ? lock_timer_base+0x72/0xa0 [ 99.873155] ? switch_mm_irqs_off+0x1bf/0x420 [ 99.874152] io_wq_submit_work+0x64/0x180 [ 99.875192] ? kthread_use_mm+0x71/0x100 [ 99.876132] io_worker_handle_work+0x267/0x440 [ 99.877233] io_wqe_worker+0x297/0x350 [ 99.878145] kthread+0x112/0x150 [ 99.878849] ? __io_worker_unuse+0x100/0x100 [ 99.879935] ? kthread_park+0x90/0x90 [ 99.880874] ret_from_fork+0x22/0x30 [ 99.881679] Modules linked in: [ 99.882493] CR2: 0000000000000000 [ 99.883324] ---[ end trace 4453745f4673190b ]--- [ 99.884289] RIP: 0010:0x0 [ 99.884837] Code: Bad RIP value. [ 99.885492] RSP: 0018:ffffa1c7c01ebc08 EFLAGS: 00010202 [ 99.886851] RAX: 0000000000000000 RBX: ffff92363acd7f00 RCX: ffff92363d461608 [ 99.888561] RDX: 0000000000000010 RSI: 00007ffe040d9e10 RDI: ffff92363acd7f00 [ 99.890203] RBP: ffffa1c7c01ebc40 R08: 0000000000000000 R09: 0000000000000000 [ 99.891907] R10: ffffffff9ec692a0 R11: 0000000000000000 R12: 0000000000000010 [ 99.894106] R13: 0000000000000000 R14: ffff92363d461608 R15: ffffa1c7c01ebc68 [ 99.896079] FS: 0000000000000000(0000) GS:ffff92363dd00000(0000) knlGS:0000000000000000 [ 99.898017] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 99.899197] CR2: ffffffffffffffd6 CR3: 000000007ac66000 CR4: 00000000000006e0 Fixes: 3296061 ("io_uring: correctly handle non ->{read,write}_iter() file_operations") Cc: stable@vger.kernel.org Signed-off-by: Guoyu Huang <hgy5945@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 18c850f upstream. There's long existed a lockdep splat because we open our bdev's under the ->device_list_mutex at mount time, which acquires the bd_mutex. Usually this goes unnoticed, but if you do loopback devices at all suddenly the bd_mutex comes with a whole host of other dependencies, which results in the splat when you mount a btrfs file system. ====================================================== WARNING: possible circular locking dependency detected 5.8.0-0.rc3.1.fc33.x86_64+debug #1 Not tainted ------------------------------------------------------ systemd-journal/509 is trying to acquire lock: ffff970831f84db0 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_record_root_in_trans+0x44/0x70 [btrfs] but task is already holding lock: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (sb_pagefaults){.+.+}-{0:0}: __sb_start_write+0x13e/0x220 btrfs_page_mkwrite+0x59/0x560 [btrfs] do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 asm_exc_page_fault+0x1e/0x30 -> #5 (&mm->mmap_lock#2){++++}-{3:3}: __might_fault+0x60/0x80 _copy_from_user+0x20/0xb0 get_sg_io_hdr+0x9a/0xb0 scsi_cmd_ioctl+0x1ea/0x2f0 cdrom_ioctl+0x3c/0x12b4 sr_block_ioctl+0xa4/0xd0 block_ioctl+0x3f/0x50 ksys_ioctl+0x82/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #4 (&cd->lock){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 sr_block_open+0xa2/0x180 __blkdev_get+0xdd/0x550 blkdev_get+0x38/0x150 do_dentry_open+0x16b/0x3e0 path_openat+0x3c9/0xa00 do_filp_open+0x75/0x100 do_sys_openat2+0x8a/0x140 __x64_sys_openat+0x46/0x70 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #3 (&bdev->bd_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 __blkdev_get+0x6a/0x550 blkdev_get+0x85/0x150 blkdev_get_by_path+0x2c/0x70 btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs] open_fs_devices+0x88/0x240 [btrfs] btrfs_open_devices+0x92/0xa0 [btrfs] btrfs_mount_root+0x250/0x490 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 vfs_kern_mount.part.0+0x71/0xb0 btrfs_mount+0x119/0x380 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x8c6/0xca0 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #2 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 btrfs_run_dev_stats+0x36/0x420 [btrfs] commit_cowonly_roots+0x91/0x2d0 [btrfs] btrfs_commit_transaction+0x4e6/0x9f0 [btrfs] btrfs_sync_file+0x38a/0x480 [btrfs] __x64_sys_fdatasync+0x47/0x80 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->tree_log_mutex){+.+.}-{3:3}: __mutex_lock+0x7b/0x820 btrfs_commit_transaction+0x48e/0x9f0 [btrfs] btrfs_sync_file+0x38a/0x480 [btrfs] __x64_sys_fdatasync+0x47/0x80 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&fs_info->reloc_mutex){+.+.}-{3:3}: __lock_acquire+0x1241/0x20c0 lock_acquire+0xb0/0x400 __mutex_lock+0x7b/0x820 btrfs_record_root_in_trans+0x44/0x70 [btrfs] start_transaction+0xd2/0x500 [btrfs] btrfs_dirty_inode+0x44/0xd0 [btrfs] file_update_time+0xc6/0x120 btrfs_page_mkwrite+0xda/0x560 [btrfs] do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 asm_exc_page_fault+0x1e/0x30 other info that might help us debug this: Chain exists of: &fs_info->reloc_mutex --> &mm->mmap_lock#2 --> sb_pagefaults Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sb_pagefaults); lock(&mm->mmap_lock#2); lock(sb_pagefaults); lock(&fs_info->reloc_mutex); *** DEADLOCK *** 3 locks held by systemd-journal/509: #0: ffff97083bdec8b8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x12e/0x4b0 #1: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs] #2: ffff97083144d6a8 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x3f8/0x500 [btrfs] stack backtrace: CPU: 0 PID: 509 Comm: systemd-journal Not tainted 5.8.0-0.rc3.1.fc33.x86_64+debug #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack+0x92/0xc8 check_noncircular+0x134/0x150 __lock_acquire+0x1241/0x20c0 lock_acquire+0xb0/0x400 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] ? lock_acquire+0xb0/0x400 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] __mutex_lock+0x7b/0x820 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs] ? kvm_sched_clock_read+0x14/0x30 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0xc/0xb0 btrfs_record_root_in_trans+0x44/0x70 [btrfs] start_transaction+0xd2/0x500 [btrfs] btrfs_dirty_inode+0x44/0xd0 [btrfs] file_update_time+0xc6/0x120 btrfs_page_mkwrite+0xda/0x560 [btrfs] ? sched_clock+0x5/0x10 do_page_mkwrite+0x4f/0x130 do_wp_page+0x3b0/0x4f0 handle_mm_fault+0xf47/0x1850 do_user_addr_fault+0x1fc/0x4b0 exc_page_fault+0x88/0x300 ? asm_exc_page_fault+0x8/0x30 asm_exc_page_fault+0x1e/0x30 RIP: 0033:0x7fa3972fdbfe Code: Bad RIP value. Fix this by not holding the ->device_list_mutex at this point. The device_list_mutex exists to protect us from modifying the device list while the file system is running. However it can also be modified by doing a scan on a device. But this action is specifically protected by the uuid_mutex, which we are holding here. We cannot race with opening at this point because we have the ->s_mount lock held during the mount. Not having the ->device_list_mutex here is perfectly safe as we're not going to change the devices at this point. CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add some comments ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 01d01ca upstream. We are currently getting this lockdep splat in btrfs/161: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc5+ lkl#20 Tainted: G E ------------------------------------------------------ mount/678048 is trying to acquire lock: ffff9b769f15b6e0 (&fs_devs->device_list_mutex){+.+.}-{3:3}, at: clone_fs_devices+0x4d/0x170 [btrfs] but task is already holding lock: ffff9b76abdb08d0 (&fs_info->chunk_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x6a/0x800 [btrfs] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __mutex_lock+0x8b/0x8f0 btrfs_init_new_device+0x2d2/0x1240 [btrfs] btrfs_ioctl+0x1de/0x2d20 [btrfs] ksys_ioctl+0x87/0xc0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #0 (&fs_devs->device_list_mutex){+.+.}-{3:3}: __lock_acquire+0x1240/0x2460 lock_acquire+0xab/0x360 __mutex_lock+0x8b/0x8f0 clone_fs_devices+0x4d/0x170 [btrfs] btrfs_read_chunk_tree+0x330/0x800 [btrfs] open_ctree+0xb7c/0x18ce [btrfs] btrfs_mount_root.cold+0x13/0xfa [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 fc_mount+0xe/0x40 vfs_kern_mount.part.0+0x71/0x90 btrfs_mount+0x13b/0x3e0 [btrfs] legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x7de/0xb30 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&fs_info->chunk_mutex); lock(&fs_devs->device_list_mutex); lock(&fs_info->chunk_mutex); lock(&fs_devs->device_list_mutex); *** DEADLOCK *** 3 locks held by mount/678048: #0: ffff9b75ff5fb0e0 (&type->s_umount_key#63/1){+.+.}-{3:3}, at: alloc_super+0xb5/0x380 #1: ffffffffc0c2fbc8 (uuid_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x54/0x800 [btrfs] #2: ffff9b76abdb08d0 (&fs_info->chunk_mutex){+.+.}-{3:3}, at: btrfs_read_chunk_tree+0x6a/0x800 [btrfs] stack backtrace: CPU: 2 PID: 678048 Comm: mount Tainted: G E 5.8.0-rc5+ lkl#20 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./890FX Deluxe5, BIOS P1.40 05/03/2011 Call Trace: dump_stack+0x96/0xd0 check_noncircular+0x162/0x180 __lock_acquire+0x1240/0x2460 ? asm_sysvec_apic_timer_interrupt+0x12/0x20 lock_acquire+0xab/0x360 ? clone_fs_devices+0x4d/0x170 [btrfs] __mutex_lock+0x8b/0x8f0 ? clone_fs_devices+0x4d/0x170 [btrfs] ? rcu_read_lock_sched_held+0x52/0x60 ? cpumask_next+0x16/0x20 ? module_assert_mutex_or_preempt+0x14/0x40 ? __module_address+0x28/0xf0 ? clone_fs_devices+0x4d/0x170 [btrfs] ? static_obj+0x4f/0x60 ? lockdep_init_map_waits+0x43/0x200 ? clone_fs_devices+0x4d/0x170 [btrfs] clone_fs_devices+0x4d/0x170 [btrfs] btrfs_read_chunk_tree+0x330/0x800 [btrfs] open_ctree+0xb7c/0x18ce [btrfs] ? super_setup_bdi_name+0x79/0xd0 btrfs_mount_root.cold+0x13/0xfa [btrfs] ? vfs_parse_fs_string+0x84/0xb0 ? rcu_read_lock_sched_held+0x52/0x60 ? kfree+0x2b5/0x310 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 fc_mount+0xe/0x40 vfs_kern_mount.part.0+0x71/0x90 btrfs_mount+0x13b/0x3e0 [btrfs] ? cred_has_capability+0x7c/0x120 ? rcu_read_lock_sched_held+0x52/0x60 ? legacy_get_tree+0x30/0x50 legacy_get_tree+0x30/0x50 vfs_get_tree+0x28/0xc0 do_mount+0x7de/0xb30 ? memdup_user+0x4e/0x90 __x64_sys_mount+0x8e/0xd0 do_syscall_64+0x52/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 This is because btrfs_read_chunk_tree() can come upon DEV_EXTENT's and then read the device, which takes the device_list_mutex. The device_list_mutex needs to be taken before the chunk_mutex, so this is a problem. We only really need the chunk mutex around adding the chunk, so move the mutex around read_one_chunk. An argument could be made that we don't even need the chunk_mutex here as it's during mount, and we are protected by various other locks. However we already have special rules for ->device_list_mutex, and I'd rather not have another special case for ->chunk_mutex. CC: stable@vger.kernel.org # 4.19+ Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit a47bd78 upstream. Dave hit this splat during testing btrfs/078: ====================================================== WARNING: possible circular locking dependency detected 5.8.0-rc6-default+ #1191 Not tainted ------------------------------------------------------ kswapd0/75 is trying to acquire lock: ffffa040e9d04ff8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] but task is already holding lock: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (fs_reclaim){+.+.}-{0:0}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 fs_reclaim_acquire.part.0+0x25/0x30 __kmalloc_track_caller+0x49/0x330 kstrdup+0x2e/0x60 __kernfs_new_node.constprop.0+0x44/0x250 kernfs_new_node+0x25/0x50 kernfs_create_link+0x34/0xa0 sysfs_do_create_link_sd+0x5e/0xd0 btrfs_sysfs_add_devices_dir+0x65/0x100 [btrfs] btrfs_init_new_device+0x44c/0x12b0 [btrfs] btrfs_ioctl+0xc3c/0x25c0 [btrfs] ksys_ioctl+0x68/0xa0 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x50/0xe0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 -> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}: __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 btrfs_chunk_alloc+0x137/0x3e0 [btrfs] find_free_extent+0xb44/0xfb0 [btrfs] btrfs_reserve_extent+0x9b/0x180 [btrfs] btrfs_alloc_tree_block+0xc1/0x350 [btrfs] alloc_tree_block_no_bg_flush+0x4a/0x60 [btrfs] __btrfs_cow_block+0x143/0x7a0 [btrfs] btrfs_cow_block+0x15f/0x310 [btrfs] push_leaf_right+0x150/0x240 [btrfs] split_leaf+0x3cd/0x6d0 [btrfs] btrfs_search_slot+0xd14/0xf70 [btrfs] btrfs_insert_empty_items+0x64/0xc0 [btrfs] __btrfs_commit_inode_delayed_items+0xb2/0x840 [btrfs] btrfs_async_run_delayed_root+0x10e/0x1d0 [btrfs] btrfs_work_helper+0x2f9/0x650 [btrfs] process_one_work+0x22c/0x600 worker_thread+0x50/0x3b0 kthread+0x137/0x150 ret_from_fork+0x1f/0x30 -> #0 (&delayed_node->mutex){+.+.}-{3:3}: check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 __mutex_lock+0xa0/0xaf0 __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 kthread+0x137/0x150 ret_from_fork+0x1f/0x30 other info that might help us debug this: Chain exists of: &delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(&fs_info->chunk_mutex); lock(fs_reclaim); lock(&delayed_node->mutex); *** DEADLOCK *** 3 locks held by kswapd0/75: #0: ffffffff8b0c8040 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30 #1: ffffffff8b0b50b8 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x54/0x2e0 #2: ffffa040e057c0e8 (&type->s_umount_key#26){++++}-{3:3}, at: trylock_super+0x16/0x50 stack backtrace: CPU: 2 PID: 75 Comm: kswapd0 Not tainted 5.8.0-rc6-default+ #1191 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014 Call Trace: dump_stack+0x78/0xa0 check_noncircular+0x16f/0x190 check_prev_add+0x98/0xa20 validate_chain+0xa8c/0x2a00 __lock_acquire+0x56f/0xaa0 lock_acquire+0xa3/0x440 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __mutex_lock+0xa0/0xaf0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? __lock_acquire+0x56f/0xaa0 ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] ? lock_acquire+0xa3/0x440 ? btrfs_evict_inode+0x138/0x560 [btrfs] ? btrfs_evict_inode+0x2fe/0x560 [btrfs] ? __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] __btrfs_release_delayed_node.part.0+0x3f/0x310 [btrfs] btrfs_evict_inode+0x3bf/0x560 [btrfs] evict+0xd6/0x1c0 dispose_list+0x48/0x70 prune_icache_sb+0x54/0x80 super_cache_scan+0x121/0x1a0 do_shrink_slab+0x175/0x420 shrink_slab+0xb1/0x2e0 shrink_node+0x192/0x600 balance_pgdat+0x31f/0x750 kswapd+0x206/0x510 ? _raw_spin_unlock_irqrestore+0x3e/0x50 ? finish_wait+0x90/0x90 ? balance_pgdat+0x750/0x750 kthread+0x137/0x150 ? kthread_stop+0x2a0/0x2a0 ret_from_fork+0x1f/0x30 This is because we're holding the chunk_mutex while adding this device and adding its sysfs entries. We actually hold different locks in different places when calling this function, the dev_replace semaphore for instance in dev replace, so instead of moving this call around simply wrap it's operations in NOFS. CC: stable@vger.kernel.org # 4.14+ Reported-by: David Sterba <dsterba@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 5a25de6 ] Freeing chip on error may lead to an Oops at the next time the system goes to resume. Fix this by removing all snd_echo_free() calls on error. Fixes: 47b5d02 ("ALSA: Echoaudio - Add suspend support #2") Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn> Link: https://lore.kernel.org/r/20200813074632.17022-1-dinghao.liu@zju.edu.cn Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 273108f ] Ext4 uses blkdev_get_by_dev() to get the block_device for journal device which does check to see if the read-only block device was opened read-only. As a result ext4 will hapily proceed mounting the file system with external journal on read-only device. This is bad as we would not be able to use the journal leading to errors later on. Instead of simply failing to mount file system in this case, treat it in a similar way we treat internal journal on read-only device. Allow to mount with -o noload in read-only mode. This can be reproduced easily like this: mke2fs -F -O journal_dev $JOURNAL_DEV 100M mkfs.$FSTYPE -F -J device=$JOURNAL_DEV $FS_DEV blockdev --setro $JOURNAL_DEV mount $FS_DEV $MNT touch $MNT/file umount $MNT leading to error like this [ 1307.318713] ------------[ cut here ]------------ [ 1307.323362] generic_make_request: Trying to write to read-only block-device dm-2 (partno 0) [ 1307.331741] WARNING: CPU: 36 PID: 3224 at block/blk-core.c:855 generic_make_request_checks+0x2c3/0x580 [ 1307.341041] Modules linked in: ext4 mbcache jbd2 rfkill intel_rapl_msr intel_rapl_common isst_if_commd [ 1307.419445] CPU: 36 PID: 3224 Comm: jbd2/dm-2 Tainted: G W I 5.8.0-rc5 #2 [ 1307.427359] Hardware name: Dell Inc. PowerEdge R740/01KPX8, BIOS 2.3.10 08/15/2019 [ 1307.434932] RIP: 0010:generic_make_request_checks+0x2c3/0x580 [ 1307.440676] Code: 94 03 00 00 48 89 df 48 8d 74 24 08 c6 05 cf 2b 18 01 01 e8 7f a4 ff ff 48 c7 c7 50e [ 1307.459420] RSP: 0018:ffffc0d70eb5fb48 EFLAGS: 00010286 [ 1307.464646] RAX: 0000000000000000 RBX: ffff9b33b2978300 RCX: 0000000000000000 [ 1307.471780] RDX: ffff9b33e12a81e0 RSI: ffff9b33e1298000 RDI: ffff9b33e1298000 [ 1307.478913] RBP: ffff9b7b9679e0c0 R08: 0000000000000837 R09: 0000000000000024 [ 1307.486044] R10: 0000000000000000 R11: ffffc0d70eb5f9f0 R12: 0000000000000400 [ 1307.493177] R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 [ 1307.500308] FS: 0000000000000000(0000) GS:ffff9b33e1280000(0000) knlGS:0000000000000000 [ 1307.508396] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1307.514142] CR2: 000055eaf4109000 CR3: 0000003dee40a006 CR4: 00000000007606e0 [ 1307.521273] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1307.528407] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1307.535538] PKRU: 55555554 [ 1307.538250] Call Trace: [ 1307.540708] generic_make_request+0x30/0x340 [ 1307.544985] submit_bio+0x43/0x190 [ 1307.548393] ? bio_add_page+0x62/0x90 [ 1307.552068] submit_bh_wbc+0x16a/0x190 [ 1307.555833] jbd2_write_superblock+0xec/0x200 [jbd2] [ 1307.560803] jbd2_journal_update_sb_log_tail+0x65/0xc0 [jbd2] [ 1307.566557] jbd2_journal_commit_transaction+0x2ae/0x1860 [jbd2] [ 1307.572566] ? check_preempt_curr+0x7a/0x90 [ 1307.576756] ? update_curr+0xe1/0x1d0 [ 1307.580421] ? account_entity_dequeue+0x7b/0xb0 [ 1307.584955] ? newidle_balance+0x231/0x3d0 [ 1307.589056] ? __switch_to_asm+0x42/0x70 [ 1307.592986] ? __switch_to_asm+0x36/0x70 [ 1307.596918] ? lock_timer_base+0x67/0x80 [ 1307.600851] kjournald2+0xbd/0x270 [jbd2] [ 1307.604873] ? finish_wait+0x80/0x80 [ 1307.608460] ? commit_timeout+0x10/0x10 [jbd2] [ 1307.612915] kthread+0x114/0x130 [ 1307.616152] ? kthread_park+0x80/0x80 [ 1307.619816] ret_from_fork+0x22/0x30 [ 1307.623400] ---[ end trace 27490236265b1630 ]--- Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Link: https://lore.kernel.org/r/20200717090605.2612-1-lczerner@redhat.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit 205d300 upstream. We have a number of "uart.port->desc.lock vs desc.lock->uart.port" lockdep reports coming from 8250 driver; this causes a bit of trouble to people, so let's fix it. The problem is reverse lock order in two different call paths: chain #1: serial8250_do_startup() spin_lock_irqsave(&port->lock); disable_irq_nosync(port->irq); raw_spin_lock_irqsave(&desc->lock) chain #2: __report_bad_irq() raw_spin_lock_irqsave(&desc->lock) for_each_action_of_desc() printk() spin_lock_irqsave(&port->lock); Fix this by changing the order of locks in serial8250_do_startup(): do disable_irq_nosync() first, which grabs desc->lock, and grab uart->port after that, so that chain #1 and chain #2 have same lock order. Full lockdep splat: ====================================================== WARNING: possible circular locking dependency detected 5.4.39 lkl#55 Not tainted ====================================================== swapper/0/0 is trying to acquire lock: ffffffffab65b6c0 (console_owner){-...}, at: console_lock_spinning_enable+0x31/0x57 but task is already holding lock: ffff88810a8e34c0 (&irq_desc_lock_class){-.-.}, at: __report_bad_irq+0x5b/0xba which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&irq_desc_lock_class){-.-.}: _raw_spin_lock_irqsave+0x61/0x8d __irq_get_desc_lock+0x65/0x89 __disable_irq_nosync+0x3b/0x93 serial8250_do_startup+0x451/0x75c uart_startup+0x1b4/0x2ff uart_port_activate+0x73/0xa0 tty_port_open+0xae/0x10a uart_open+0x1b/0x26 tty_open+0x24d/0x3a0 chrdev_open+0xd5/0x1cc do_dentry_open+0x299/0x3c8 path_openat+0x434/0x1100 do_filp_open+0x9b/0x10a do_sys_open+0x15f/0x3d7 kernel_init_freeable+0x157/0x1dd kernel_init+0xe/0x105 ret_from_fork+0x27/0x50 -> #1 (&port_lock_key){-.-.}: _raw_spin_lock_irqsave+0x61/0x8d serial8250_console_write+0xa7/0x2a0 console_unlock+0x3b7/0x528 vprintk_emit+0x111/0x17f printk+0x59/0x73 register_console+0x336/0x3a4 uart_add_one_port+0x51b/0x5be serial8250_register_8250_port+0x454/0x55e dw8250_probe+0x4dc/0x5b9 platform_drv_probe+0x67/0x8b really_probe+0x14a/0x422 driver_probe_device+0x66/0x130 device_driver_attach+0x42/0x5b __driver_attach+0xca/0x139 bus_for_each_dev+0x97/0xc9 bus_add_driver+0x12b/0x228 driver_register+0x64/0xed do_one_initcall+0x20c/0x4a6 do_initcall_level+0xb5/0xc5 do_basic_setup+0x4c/0x58 kernel_init_freeable+0x13f/0x1dd kernel_init+0xe/0x105 ret_from_fork+0x27/0x50 -> #0 (console_owner){-...}: __lock_acquire+0x118d/0x2714 lock_acquire+0x203/0x258 console_lock_spinning_enable+0x51/0x57 console_unlock+0x25d/0x528 vprintk_emit+0x111/0x17f printk+0x59/0x73 __report_bad_irq+0xa3/0xba note_interrupt+0x19a/0x1d6 handle_irq_event_percpu+0x57/0x79 handle_irq_event+0x36/0x55 handle_fasteoi_irq+0xc2/0x18a do_IRQ+0xb3/0x157 ret_from_intr+0x0/0x1d cpuidle_enter_state+0x12f/0x1fd cpuidle_enter+0x2e/0x3d do_idle+0x1ce/0x2ce cpu_startup_entry+0x1d/0x1f start_kernel+0x406/0x46a secondary_startup_64+0xa4/0xb0 other info that might help us debug this: Chain exists of: console_owner --> &port_lock_key --> &irq_desc_lock_class Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&irq_desc_lock_class); lock(&port_lock_key); lock(&irq_desc_lock_class); lock(console_owner); *** DEADLOCK *** 2 locks held by swapper/0/0: #0: ffff88810a8e34c0 (&irq_desc_lock_class){-.-.}, at: __report_bad_irq+0x5b/0xba #1: ffffffffab65b5c0 (console_lock){+.+.}, at: console_trylock_spinning+0x20/0x181 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.39 lkl#55 Hardware name: XXXXXX Call Trace: <IRQ> dump_stack+0xbf/0x133 ? print_circular_bug+0xd6/0xe9 check_noncircular+0x1b9/0x1c3 __lock_acquire+0x118d/0x2714 lock_acquire+0x203/0x258 ? console_lock_spinning_enable+0x31/0x57 console_lock_spinning_enable+0x51/0x57 ? console_lock_spinning_enable+0x31/0x57 console_unlock+0x25d/0x528 ? console_trylock+0x18/0x4e vprintk_emit+0x111/0x17f ? lock_acquire+0x203/0x258 printk+0x59/0x73 __report_bad_irq+0xa3/0xba note_interrupt+0x19a/0x1d6 handle_irq_event_percpu+0x57/0x79 handle_irq_event+0x36/0x55 handle_fasteoi_irq+0xc2/0x18a do_IRQ+0xb3/0x157 common_interrupt+0xf/0xf </IRQ> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Fixes: 768aec0 ("serial: 8250: fix shared interrupts issues with SMP and RT kernels") Reported-by: Guenter Roeck <linux@roeck-us.net> Reported-by: Raul Rangel <rrangel@google.com> BugLink: https://bugs.chromium.org/p/chromium/issues/detail?id=1114800 Link: https://lore.kernel.org/lkml/CAHQZ30BnfX+gxjPm1DUd5psOTqbyDh4EJE=2=VAMW_VDafctkA@mail.gmail.com/T/#u Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200817022646.1484638-1-sergey.senozhatsky@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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the commit <1c4404efcf2c0> ("<io_uring: make sure async workqueue
is canceled on exit>") caused a crash in io_sq_wq_submit_work().
when io_ring-wq get a req form async_list, which not have been
added to task_list. Then try to delete the req from task_list will caused
a "NULL pointer dereference".
Ensure add req to async_list and task_list at the sametime.
The crash log looks like this:
[95995.973638] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[95995.979123] pgd = c20c8964
[95995.981803] [00000000] *pgd=1c72d831, *pte=00000000, *ppte=00000000
[95995.988043] Internal error: Oops: 817 [#1] SMP ARM
[95995.992814] Modules linked in: bpfilter(-)
[95995.996898] CPU: 1 PID: 15661 Comm: kworker/u8:5 Not tainted 5.4.56 #2
[95996.003406] Hardware name: Amlogic Meson platform
[95996.008108] Workqueue: io_ring-wq io_sq_wq_submit_work
[95996.013224] PC is at io_sq_wq_submit_work+0x1f4/0x5c4
[95996.018261] LR is at walk_stackframe+0x24/0x40
[95996.022685] pc : [<c059b898>] lr : [<c030da7c>] psr: 600f0093
[95996.028936] sp : dc6f7e88 ip : dc6f7df0 fp : dc6f7ef4
[95996.034148] r10: deff9800 r9 : dc1d1694 r8 : dda58b80
[95996.039358] r7 : dc6f6000 r6 : dc6f7ebc r5 : dc1d1600 r4 : deff99c0
[95996.045871] r3 : 0000cb5d r2 : 00000000 r1 : ef6b9b80 r0 : c059b88c
[95996.052385] Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user
[95996.059593] Control: 10c5387d Table: 22be804a DAC: 00000055
[95996.065325] Process kworker/u8:5 (pid: 15661, stack limit = 0x78013c69)
[95996.071923] Stack: (0xdc6f7e88 to 0xdc6f8000)
[95996.076268] 7e80: dc6f7ecc dc6f7e98 00000000 c1f06c08 de9dc800 deff9a04
[95996.084431] 7ea0: 00000000 dc6f7f7c 00000000 c1f65808 0000080c dc677a00 c1ee9bd0 dc6f7ebc
[95996.092594] 7ec0: dc6f7ebc d085c8f6 c0445a90 dc1d1e00 e008f300 c0288400 e4ef7100 00000000
[95996.100757] 7ee0: c20d45b0 e4ef7115 dc6f7f34 dc6f7ef8 c03725f0 c059b6b0 c0288400 c0288400
[95996.108921] 7f00: c0288400 00000001 c0288418 e008f300 c0288400 e008f314 00000088 c0288418
[95996.117083] 7f20: c1f03d00 dc6f6038 dc6f7f7c dc6f7f38 c0372df8 c037246c dc6f7f5c 00000000
[95996.125245] 7f40: c1f03d00 c1f03d00 c20d3cbe c0288400 dc6f7f7c e1c43880 e4fa7980 00000000
[95996.133409] 7f60: e008f300 c0372d9c e48bbe74 e1c4389c dc6f7fac dc6f7f80 c0379244 c0372da8
[95996.141570] 7f80: 600f0093 e4fa7980 c0379108 00000000 00000000 00000000 00000000 00000000
[95996.149734] 7fa0: 00000000 dc6f7fb0 c03010ac c0379114 00000000 00000000 00000000 00000000
[95996.157897] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[95996.166060] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[95996.174217] Backtrace:
[95996.176662] [<c059b6a4>] (io_sq_wq_submit_work) from [<c03725f0>] (process_one_work+0x190/0x4c0)
[95996.185425] r10:e4ef7115 r9:c20d45b0 r8:00000000 r7:e4ef7100 r6:c0288400 r5:e008f300
[95996.193237] r4:dc1d1e00
[95996.195760] [<c0372460>] (process_one_work) from [<c0372df8>] (worker_thread+0x5c/0x5bc)
[95996.203836] r10:dc6f6038 r9:c1f03d00 r8:c0288418 r7:00000088 r6:e008f314 r5:c0288400
[95996.211647] r4:e008f300
[95996.214173] [<c0372d9c>] (worker_thread) from [<c0379244>] (kthread+0x13c/0x168)
[95996.221554] r10:e1c4389c r9:e48bbe74 r8:c0372d9c r7:e008f300 r6:00000000 r5:e4fa7980
[95996.229363] r4:e1c43880
[95996.231888] [<c0379108>] (kthread) from [<c03010ac>] (ret_from_fork+0x14/0x28)
[95996.239088] Exception stack(0xdc6f7fb0 to 0xdc6f7ff8)
[95996.244127] 7fa0: 00000000 00000000 00000000 00000000
[95996.252291] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[95996.260453] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
[95996.267054] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0379108
[95996.274866] r4:e4fa7980 r3:600f0093
[95996.278430] Code: eb3a59e1 e5952098 e5951094 e5812004 (e5821000)
Signed-off-by: Xin Yin <yinxin_1989@aliyun.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This uses the GCC builtins for the atomic ops, avoiding
architecture-specific code.