Hello, syzbot found the following issue on: HEAD commit: 52025ebbb518 Add linux-next specific files for 20230508 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=10c27582280000 kernel config: https://syzkaller.appspot.com/x/.config?x=d1f55a88ec660cdb dashboard link: https://syzkaller.appspot.com/bug?extid=3c6cac1550288f8e7060 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/912ed8ef786f/disk-52025ebb.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/d53b6c9decdc/vmlinux-52025ebb.xz kernel image: https://storage.googleapis.com/syzbot-assets/f0d8a6edd999/bzImage-52025ebb.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3c6cac1550288f8e7060@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: 4439, name: syslogd preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 2 locks held by syslogd/4439: #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:785 [inline] #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: lookup_slow fs/namei.c:1706 [inline] #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: walk_component+0x332/0x5a0 fs/namei.c:1998 #1: ffffffff8c799800 (rcu_read_lock){....}-{1:2}, at: lru_gen_refault mm/workingset.c:293 [inline] #1: ffffffff8c799800 (rcu_read_lock){....}-{1:2}, at: workingset_refault+0x175/0x11e0 mm/workingset.c:528 CPU: 1 PID: 4439 Comm: syslogd Not tainted 6.4.0-rc1-next-20230508-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:10153 might_alloc include/linux/sched/mm.h:306 [inline] slab_pre_alloc_hook mm/slab.h:670 [inline] slab_alloc_node mm/slub.c:3433 [inline] slab_alloc mm/slub.c:3459 [inline] __kmem_cache_alloc_lru mm/slub.c:3466 [inline] kmem_cache_alloc+0x357/0x3b0 mm/slub.c:3475 kmem_cache_zalloc include/linux/slab.h:670 [inline] alloc_buffer_head+0x24/0x150 fs/buffer.c:3044 folio_alloc_buffers+0x2f2/0x810 fs/buffer.c:941 alloc_page_buffers fs/buffer.c:976 [inline] grow_dev_page fs/buffer.c:1084 [inline] grow_buffers fs/buffer.c:1130 [inline] __getblk_slow+0x612/0x1230 fs/buffer.c:1157 __getblk_gfp+0x72/0x80 fs/buffer.c:1452 sb_getblk include/linux/buffer_head.h:369 [inline] ext4_getblk+0x211/0x850 fs/ext4/inode.c:845 ext4_bread_batch+0x82/0x500 fs/ext4/inode.c:912 __ext4_find_entry+0x451/0x1050 fs/ext4/namei.c:1650 ext4_lookup_entry fs/ext4/namei.c:1751 [inline] ext4_lookup fs/ext4/namei.c:1819 [inline] ext4_lookup+0x500/0x700 fs/ext4/namei.c:1810 __lookup_slow+0x24c/0x460 fs/namei.c:1690 lookup_slow fs/namei.c:1707 [inline] walk_component+0x33f/0x5a0 fs/namei.c:1998 link_path_walk.part.0+0x74e/0xd60 fs/namei.c:2325 link_path_walk fs/namei.c:2250 [inline] path_openat+0x25c/0x2750 fs/namei.c:3787 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1383 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: 0033:0x7f97344a89a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc296981d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055d433717910 RCX: 00007f97344a89a4 RDX: 0000000000000d41 RSI: 00007f9734647443 RDI: 00000000ffffff9c RBP: 00007f9734647443 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000d41 R13: 000000006459d39e R14: 0000000000000005 R15: 000055d433717a60 </TASK> BUG: sleeping function called from invalid context at include/linux/buffer_head.h:408 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 4439, name: syslogd preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 2 locks held by syslogd/4439: #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:785 [inline] #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: lookup_slow fs/namei.c:1706 [inline] #0: ffff888085665e00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: walk_component+0x332/0x5a0 fs/namei.c:1998 #1: ffffffff8c799800 (rcu_read_lock){....}-{1:2}, at: lru_gen_refault mm/workingset.c:293 [inline] #1: ffffffff8c799800 (rcu_read_lock){....}-{1:2}, at: workingset_refault+0x175/0x11e0 mm/workingset.c:528 CPU: 1 PID: 4439 Comm: syslogd Tainted: G W 6.4.0-rc1-next-20230508-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:10153 lock_buffer include/linux/buffer_head.h:408 [inline] ext4_read_bh_lock+0x28/0xc0 fs/ext4/super.c:208 ext4_bread_batch+0x2cc/0x500 fs/ext4/inode.c:923 __ext4_find_entry+0x451/0x1050 fs/ext4/namei.c:1650 ext4_lookup_entry fs/ext4/namei.c:1751 [inline] ext4_lookup fs/ext4/namei.c:1819 [inline] ext4_lookup+0x500/0x700 fs/ext4/namei.c:1810 __lookup_slow+0x24c/0x460 fs/namei.c:1690 lookup_slow fs/namei.c:1707 [inline] walk_component+0x33f/0x5a0 fs/namei.c:1998 link_path_walk.part.0+0x74e/0xd60 fs/namei.c:2325 link_path_walk fs/namei.c:2250 [inline] path_openat+0x25c/0x2750 fs/namei.c:3787 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1383 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: 0033:0x7f97344a89a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc296981d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055d433717910 RCX: 00007f97344a89a4 RDX: 0000000000000d41 RSI: 00007f9734647443 RDI: 00000000ffffff9c RBP: 00007f9734647443 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000d41 R13: 000000006459d39e R14: 0000000000000005 R15: 000055d433717a60 </TASK> ------------[ cut here ]------------ Voluntary context switch within RCU read-side critical section! WARNING: CPU: 0 PID: 4439 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0xbb9/0x1800 kernel/rcu/tree_plugin.h:318 Modules linked in: CPU: 0 PID: 4439 Comm: syslogd Tainted: G W 6.4.0-rc1-next-20230508-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:318 Code: 9d d0 67 00 4c 8b 4c 24 30 8b 4c 24 28 48 8b 54 24 20 e9 8f 03 00 00 48 c7 c7 e0 2f 4e 8a c6 05 19 97 f5 0c 01 e8 67 bb 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:ffffc9000312f210 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff8880b983d4c0 RCX: 0000000000000000 RDX: ffff88806a4b1dc0 RSI: ffffffff814bf407 RDI: 0000000000000001 RBP: ffff88806a4b1dc0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000186c8 R12: 0000000000000000 R13: ffff88806a4b1dc0 R14: ffffffff8e7abcf0 R15: ffff8880b983c5c0 FS: 00007f9734354380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feeab7831b8 CR3: 000000002780a000 CR4: 00000000003506f0 DR0: 00000000ffff070c DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: <TASK> __schedule+0x276/0x5790 kernel/sched/core.c:6569 schedule+0xde/0x1a0 kernel/sched/core.c:6745 io_schedule+0xbe/0x130 kernel/sched/core.c:8979 bit_wait_io+0x16/0xe0 kernel/sched/wait_bit.c:209 __wait_on_bit+0x64/0x180 kernel/sched/wait_bit.c:49 out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:64 wait_on_bit_io include/linux/wait_bit.h:101 [inline] __wait_on_buffer+0x63/0x70 fs/buffer.c:123 wait_on_buffer include/linux/buffer_head.h:398 [inline] __ext4_find_entry+0x590/0x1050 fs/ext4/namei.c:1660 ext4_lookup_entry fs/ext4/namei.c:1751 [inline] ext4_lookup fs/ext4/namei.c:1819 [inline] ext4_lookup+0x500/0x700 fs/ext4/namei.c:1810 __lookup_slow+0x24c/0x460 fs/namei.c:1690 lookup_slow fs/namei.c:1707 [inline] walk_component+0x33f/0x5a0 fs/namei.c:1998 link_path_walk.part.0+0x74e/0xd60 fs/namei.c:2325 link_path_walk fs/namei.c:2250 [inline] path_openat+0x25c/0x2750 fs/namei.c:3787 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1383 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: 0033:0x7f97344a89a4 Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 RSP: 002b:00007ffc296981d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055d433717910 RCX: 00007f97344a89a4 RDX: 0000000000000d41 RSI: 00007f9734647443 RDI: 00000000ffffff9c RBP: 00007f9734647443 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000d41 R13: 000000006459d39e R14: 0000000000000005 R15: 000055d433717a60 </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
