Hello, syzbot found the following issue on: HEAD commit: 578215f3e21c Add linux-next specific files for 20230510 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=17fa43b6280000 kernel config: https://syzkaller.appspot.com/x/.config?x=bb5a64fc61c29c5f dashboard link: https://syzkaller.appspot.com/bug?extid=5a5f3b3df8fc04673151 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/61ae2512b5cb/disk-578215f3.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e16190a5b183/vmlinux-578215f3.xz kernel image: https://storage.googleapis.com/syzbot-assets/04000a0b9ddf/bzImage-578215f3.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5a5f3b3df8fc04673151@xxxxxxxxxxxxxxxxxxxxxxxxx BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 21075, name: udevd preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 2 locks held by udevd/21075: #0: ffff88801a8829b0 (mapping.invalidate_lock#2){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:830 [inline] #0: ffff88801a8829b0 (mapping.invalidate_lock#2){.+.+}-{3:3}, at: page_cache_ra_unbounded+0x153/0x5e0 mm/readahead.c:226 #1: ffffffff8c7991c0 (rcu_read_lock){....}-{1:2}, at: lru_gen_refault mm/workingset.c:293 [inline] #1: ffffffff8c7991c0 (rcu_read_lock){....}-{1:2}, at: workingset_refault+0x175/0x11e0 mm/workingset.c:528 CPU: 1 PID: 21075 Comm: udevd Not tainted 6.4.0-rc1-next-20230510-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106 __might_resched+0x358/0x580 kernel/sched/core.c:10148 might_alloc include/linux/sched/mm.h:306 [inline] mempool_alloc+0x1c4/0x360 mm/mempool.c:388 bio_alloc_bioset+0x41e/0x900 block/bio.c:543 bio_alloc include/linux/bio.h:427 [inline] do_mpage_readpage+0xe8c/0x1960 fs/mpage.c:298 mpage_readahead+0x344/0x580 fs/mpage.c:382 read_pages+0x1a2/0xd40 mm/readahead.c:161 page_cache_ra_unbounded+0x477/0x5e0 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra+0x333/0x470 mm/readahead.c:331 page_cache_sync_ra+0x105/0x200 mm/readahead.c:705 page_cache_sync_readahead include/linux/pagemap.h:1211 [inline] filemap_get_pages+0x28d/0x1620 mm/filemap.c:2598 filemap_read+0x35e/0xc70 mm/filemap.c:2693 blkdev_read_iter+0x3eb/0x760 block/fops.c:609 call_read_iter include/linux/fs.h:1862 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4b1/0x8a0 fs/read_write.c:470 ksys_read+0x12b/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1805316b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffccfcc4668 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1805316b6a RDX: 0000000000000400 RSI: 000055ca7c932ca8 RDI: 0000000000000009 RBP: 0000000000000400 R08: 000055ca7c932c80 R09: 0000000000000008 R10: 0000000000000051 R11: 0000000000000246 R12: 000055ca7c932c80 R13: 000055ca7c932c98 R14: 000055ca7c92c118 R15: 000055ca7c92c0c0 </TASK> ============================= [ BUG: Invalid wait context ] 6.4.0-rc1-next-20230510-syzkaller #0 Tainted: G W ----------------------------- udevd/21075 is trying to lock: ffff88801a8829b0 (mapping.invalidate_lock#2){.+.+}-{3:3}, at: filemap_invalidate_lock_shared include/linux/fs.h:830 [inline] (mapping.invalidate_lock#2){.+.+}-{3:3}, at: filemap_update_page mm/filemap.c:2474 [inline] (mapping.invalidate_lock#2){.+.+}-{3:3}, at: filemap_get_pages+0x743/0x1620 mm/filemap.c:2622 other info that might help us debug this: context-{4:4} 1 lock held by udevd/21075: #0: ffffffff8c7991c0 (rcu_read_lock){....}-{1:2}, at: lru_gen_refault mm/workingset.c:293 [inline] #0: ffffffff8c7991c0 (rcu_read_lock){....}-{1:2}, at: workingset_refault+0x175/0x11e0 mm/workingset.c:528 stack backtrace: CPU: 1 PID: 21075 Comm: udevd Tainted: G W 6.4.0-rc1-next-20230510-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_lock_invalid_wait_context kernel/locking/lockdep.c:4729 [inline] check_wait_context kernel/locking/lockdep.c:4799 [inline] __lock_acquire+0x15d5/0x5f30 kernel/locking/lockdep.c:5038 lock_acquire.part.0+0x11c/0x370 kernel/locking/lockdep.c:5705 down_read+0x3d/0x50 kernel/locking/rwsem.c:1520 filemap_invalidate_lock_shared include/linux/fs.h:830 [inline] filemap_update_page mm/filemap.c:2474 [inline] filemap_get_pages+0x743/0x1620 mm/filemap.c:2622 filemap_read+0x35e/0xc70 mm/filemap.c:2693 blkdev_read_iter+0x3eb/0x760 block/fops.c:609 call_read_iter include/linux/fs.h:1862 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4b1/0x8a0 fs/read_write.c:470 ksys_read+0x12b/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1805316b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffccfcc4668 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1805316b6a RDX: 0000000000000400 RSI: 000055ca7c932ca8 RDI: 0000000000000009 RBP: 0000000000000400 R08: 000055ca7c932c80 R09: 0000000000000008 R10: 0000000000000051 R11: 0000000000000246 R12: 000055ca7c932c80 R13: 000055ca7c932c98 R14: 000055ca7c92c118 R15: 000055ca7c92c0c0 </TASK> BUG: sleeping function called from invalid context at lib/iov_iter.c:535 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 21075, name: udevd preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 INFO: lockdep is turned off. CPU: 0 PID: 21075 Comm: udevd Tainted: G W 6.4.0-rc1-next-20230510-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x136/0x150 lib/dump_stack.c:106 __might_resched+0x358/0x580 kernel/sched/core.c:10148 __might_fault+0x79/0x190 mm/memory.c:5732 _copy_to_iter+0x328/0x1360 lib/iov_iter.c:535 copy_page_to_iter lib/iov_iter.c:742 [inline] copy_page_to_iter+0x125/0x1e0 lib/iov_iter.c:727 copy_folio_to_iter include/linux/uio.h:197 [inline] filemap_read+0x682/0xc70 mm/filemap.c:2745 blkdev_read_iter+0x3eb/0x760 block/fops.c:609 call_read_iter include/linux/fs.h:1862 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4b1/0x8a0 fs/read_write.c:470 ksys_read+0x12b/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1805316b6a Code: 00 3d 00 00 41 00 75 0d 50 48 8d 3d 2d 08 0a 00 e8 ea 7d 01 00 31 c0 e9 07 ff ff ff 64 8b 04 25 18 00 00 00 85 c0 75 1b 0f 05 <48> 3d 00 f0 ff ff 76 6c 48 8b 15 8f a2 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffccfcc4668 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1805316b6a RDX: 0000000000000400 RSI: 000055ca7c932ca8 RDI: 0000000000000009 RBP: 0000000000000400 R08: 000055ca7c932c80 R09: 0000000000000008 R10: 0000000000000051 R11: 0000000000000246 R12: 000055ca7c932c80 R13: 000055ca7c932c98 R14: 000055ca7c92c118 R15: 000055ca7c92c0c0 </TASK> ------------[ cut here ]------------ Voluntary context switch within RCU read-side critical section! WARNING: CPU: 0 PID: 21075 at kernel/rcu/tree_plugin.h:320 rcu_note_context_switch+0xbb9/0x1800 kernel/rcu/tree_plugin.h:320 Modules linked in: CPU: 0 PID: 21075 Comm: udevd Tainted: G W 6.4.0-rc1-next-20230510-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:rcu_note_context_switch+0xbb9/0x1800 kernel/rcu/tree_plugin.h:320 Code: fd 04 68 00 4c 8b 4c 24 30 8b 4c 24 28 48 8b 54 24 20 e9 8f 03 00 00 48 c7 c7 c0 2a 4e 8a c6 05 93 44 f6 0c 01 e8 17 b5 dc ff <0f> 0b e9 4c f5 ff ff 81 e5 ff ff ff 7f 0f 84 d7 f6 ff ff 65 48 8b RSP: 0018:ffffc900094f7938 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff8880b983d4c0 RCX: 0000000000000000 RDX: ffff88802211bb80 RSI: ffffffff814bc477 RDI: 0000000000000001 RBP: ffff88802211bb80 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 216e6f6974636573 R12: 0000000000000000 R13: ffff88802211bb80 R14: ffffffff8e7b4130 R15: ffff8880b983c5c0 FS: 00007f18056c2c80(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00024b000 CR3: 00000000ace41000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __schedule+0x276/0x5790 kernel/sched/core.c:6569 schedule+0xde/0x1a0 kernel/sched/core.c:6745 schedule_hrtimeout_range_clock+0x45d/0x4b0 kernel/time/hrtimer.c:2298 ep_poll fs/eventpoll.c:1925 [inline] do_epoll_wait+0x1210/0x1900 fs/eventpoll.c:2322 __do_sys_epoll_wait fs/eventpoll.c:2334 [inline] __se_sys_epoll_wait fs/eventpoll.c:2329 [inline] __x64_sys_epoll_wait+0x15c/0x280 fs/eventpoll.c:2329 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f1805323457 Code: 73 01 c3 48 8b 0d d1 d9 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 e8 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 76 48 8b 15 a2 d9 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffccfcc9bf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1805323457 RDX: 0000000000000004 RSI: 00007ffccfcc9c38 RDI: 0000000000000004 RBP: 000055ca7c92cd00 R08: 0000000000000007 R09: 9f790a821dee0ced R10: 00000000ffffffff R11: 0000000000000246 R12: 000055ca7c915af0 R13: 00007ffccfcc9c38 R14: 0000000000000008 R15: 000055ca7c90b910 </TASK> --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup