[syzbot] [ext4?] INFO: task hung in __writeback_inodes_sb_nr (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 62d8779610bb Merge tag 'ext4_for_linus_stable' of git://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1623de37280000
kernel config: https://syzkaller.appspot.com/x/.config?x=ac246111fb601aec
dashboard link: https://syzkaller.appspot.com/bug?extid=38d04642cea49f3a3d2e
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/f2ffbf05c9a8/disk-62d87796.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4809ae14c9e7/vmlinux-62d87796.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9cd8b18ed845/bzImage-62d87796.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+38d046...@syzkaller.appspotmail.com

INFO: task syz-executor.2:687 blocked for more than 143 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:23232 pid:687 ppid:24312 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fd6b008c391
RSP: 002b:0000000020000160 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd6b01abf80 RCX: 00007fd6b008c389
RDX: 0000000020000180 RSI: 0000000020000160 RDI: 0000000002000000
RBP: 00007fd6b00d7493 R08: 0000000020000200 R09: 0000000020000200
R10: 00000000200001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffddfff939f R14: 00007fd6b0dfd300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.4:740 blocked for more than 143 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:23248 pid:740 ppid:542 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fbf7328c391
RSP: 002b:0000000020000160 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fbf733ac050 RCX: 00007fbf7328c389
RDX: 0000000020000180 RSI: 0000000020000160 RDI: 0000000002000000
RBP: 00007fbf732d7493 R08: 0000000020000200 R09: 0000000020000200
R10: 00000000200001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc83f3088f R14: 00007fbf74061300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.4:885 blocked for more than 145 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:23824 pid:885 ppid:542 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fbf7328c391
RSP: 002b:0000000020000160 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fbf733abf80 RCX: 00007fbf7328c389
RDX: 0000000020000180 RSI: 0000000020000160 RDI: 0000000002000000
RBP: 00007fbf732d7493 R08: 0000000020000200 R09: 0000000020000200
R10: 00000000200001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc83f3088f R14: 00007fbf74082300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.4:908 blocked for more than 146 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:23944 pid:908 ppid:542 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fbf7328c391
RSP: 002b:0000000020000280 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fbf733abf80 RCX: 00007fbf7328c389
RDX: 00000000200002c0 RSI: 0000000020000280 RDI: 0000000000000200
RBP: 00007fbf732d7493 R08: 0000000020000340 R09: 0000000020000340
R10: 0000000020000300 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc83f3088f R14: 00007fbf74082300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.4:936 blocked for more than 147 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:23944 pid:936 ppid:542 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fbf7328c391
RSP: 002b:0000000020000160 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fbf733abf80 RCX: 00007fbf7328c389
RDX: 0000000020000180 RSI: 0000000020000160 RDI: 0000000002000000
RBP: 00007fbf732d7493 R08: 0000000020000200 R09: 0000000020000200
R10: 00000000200001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffc83f3088f R14: 00007fbf74082300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.2:971 blocked for more than 147 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:22928 pid:971 ppid:24312 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fd6b008c391
RSP: 002b:0000000020000280 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd6b01abf80 RCX: 00007fd6b008c389
RDX: 00000000200002c0 RSI: 0000000020000280 RDI: 0000000000000200
RBP: 00007fd6b00d7493 R08: 0000000020000340 R09: 0000000020000340
R10: 0000000020000300 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffddfff939f R14: 00007fd6b0dfd300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.2:983 blocked for more than 148 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:23776 pid:983 ppid:24312 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fd6b008c391
RSP: 002b:0000000020000160 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd6b01abf80 RCX: 00007fd6b008c389
RDX: 0000000020000180 RSI: 0000000020000160 RDI: 0000000002000000
RBP: 00007fd6b00d7493 R08: 0000000020000200 R09: 0000000020000200
R10: 00000000200001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffddfff939f R14: 00007fd6b0dfd300 R15: 0000000000022000
</TASK>
INFO: task syz-executor.2:997 blocked for more than 148 seconds.
Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:23744 pid:997 ppid:24312 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5343 [inline]
__schedule+0xc9a/0x5880 kernel/sched/core.c:6669
schedule+0xde/0x1a0 kernel/sched/core.c:6745
wb_wait_for_completion+0x182/0x240 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d7/0x280 fs/fs-writeback.c:2644
try_to_writeback_inodes_sb+0x98/0xc0 fs/fs-writeback.c:2692
ext4_nonda_switch+0x1aa/0x1f0 fs/ext4/inode.c:2864
ext4_da_write_begin+0x172/0x8c0 fs/ext4/inode.c:2891
generic_perform_write+0x256/0x570 mm/filemap.c:3929
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:289
ext4_file_write_iter+0xbe0/0x1740 fs/ext4/file.c:710
__kernel_write_iter+0x262/0x7a0 fs/read_write.c:517
dump_emit_page fs/coredump.c:888 [inline]
dump_user_range+0x23c/0x710 fs/coredump.c:915
elf_core_dump+0x277e/0x36e0 fs/binfmt_elf.c:2142
do_coredump+0x2f2b/0x4020 fs/coredump.c:764
get_signal+0x1c02/0x25b0 kernel/signal.c:2862
arch_do_signal_or_restart+0x79/0x5c0 arch/x86/kernel/signal.c:306
exit_to_user_mode_loop kernel/entry/common.c:168 [inline]
exit_to_user_mode_prepare+0x11f/0x240 kernel/entry/common.c:204
irqentry_exit_to_user_mode+0x9/0x40 kernel/entry/common.c:310
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:564
RIP: 0033:0x7fd6b008c391
RSP: 002b:0000000020000280 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd6b01abf80 RCX: 00007fd6b008c389
RDX: 00000000200002c0 RSI: 0000000020000280 RDI: 0000000000000200
RBP: 00007fd6b00d7493 R08: 0000000020000340 R09: 0000000020000340
R10: 0000000020000300 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ffddfff939f R14: 00007fd6b0dfd300 R15: 0000000000022000
</TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/13:
#0: ffffffff8c7984b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:518
1 lock held by rcu_tasks_trace/14:
#0: ffffffff8c7981b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:518
1 lock held by khungtaskd/28:
#0: ffffffff8c7990c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6559
3 locks held by kworker/u4:3/46:
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1324 [inline]
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:643 [inline]
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:670 [inline]
#0: ffff888145672138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x883/0x15e0 kernel/workqueue.c:2376
#1: ffffc90000b77db0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8b7/0x15e0 kernel/workqueue.c:2380
#2: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
2 locks held by getty/4753:
#0: ffff88802aec0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900015802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2176
3 locks held by syz-executor.2/24312:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff88803fe02c00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff88803fe02c00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff888083300400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff888083300400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316
3 locks held by syz-executor.2/687:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082afd400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082afd400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.4/740:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88808724c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88808724c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.4/885:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888046cf0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888046cf0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.4/908:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88805471a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88805471a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.4/936:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888050412c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888050412c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.2/971:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880874e5e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880874e5e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.2/983:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88808724b600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88808724b600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
3 locks held by syz-executor.2/997:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082afca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082afca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
#2: ffff88802c31c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: try_to_writeback_inodes_sb+0x21/0xc0 fs/fs-writeback.c:2689
1 lock held by syz-executor.0/5907:
#0: ffff8880546eac00 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xd1/0x6f0 fs/readdir.c:55
1 lock held by syz-executor.1/7188:
#0: ffff888082aeb600 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xd1/0x6f0 fs/readdir.c:55
1 lock held by syz-executor.0/7562:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/7739:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/7802:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/7812:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/7827:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/7838:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/7856:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.2/7858:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.5/8636:
#0: ffff888082aec000 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xd1/0x6f0 fs/readdir.c:55
1 lock held by syz-executor.5/8731:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.5/8734:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
2 locks held by syz-executor.5/8877:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880870e4000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880870e4000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/8885:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082f0f200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082f0f200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/8886:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082f0de00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082f0de00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.2/8888:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082f0a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082f0a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/8889:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082f0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082f0e800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/8890:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880870e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880870e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/8891:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880870e5400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880870e5400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/8907:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082aed400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082aed400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/8911:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803cddb600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803cddb600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.2/8912:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082ae8e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082ae8e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/8918:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880826e9800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880826e9800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/8919:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803cddca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803cddca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/8923:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880826eca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880826eca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/8924:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880826ec000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880826ec000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
3 locks held by syz-executor.2/8938:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
#1: ffff88814be58990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfb4/0x14e0 fs/jbd2/transaction.c:461
#2: ffff888078e9f088 (&ei->i_data_sem){++++}-{3:3}, at: ext4_map_blocks+0x707/0x18d0 fs/ext4/inode.c:616
2 locks held by syz-executor.1/8942:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888078e9de00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888078e9de00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
1 lock held by syz-executor.4/8955:
#0: ffff8880546eb600 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xd1/0x6f0 fs/readdir.c:55
1 lock held by syz-executor.0/9094:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/9096:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.3/9157:
#0: ffff88803444e800 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: iterate_dir+0xd1/0x6f0 fs/readdir.c:55
2 locks held by syz-executor.3/9599:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88802fd5d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88802fd5d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9600:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88802fd5ca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88802fd5ca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.2/9619:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803e361800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803e361800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/9625:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888046cf3600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888046cf3600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
1 lock held by syz-executor.1/9626:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
2 locks held by syz-executor.3/9627:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803ce98e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803ce98e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9629:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888046cf7200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888046cf7200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9635:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88805471c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88805471c000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/9637:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888046cf2c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888046cf2c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/9640:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88805471d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88805471d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
1 lock held by syz-executor.2/9785:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/9790:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/9795:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/9796:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/9797:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/9806:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.0/9807:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/9815:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/9819:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.2/9829:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.1/9847:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
1 lock held by syz-executor.2/9852:
#0: ffff88802c31eb98 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: do_writepages+0x1a8/0x640 mm/page-writeback.c:2551
2 locks held by syz-executor.4/9858:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888087255400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888087255400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9861:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803e364a00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803e364a00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9863:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803e367200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803e367200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9866:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88802fd5ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88802fd5ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/9869:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88802fd5a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88802fd5a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9873:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082afc000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082afc000 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/9875:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803450ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803450ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9879:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082af8e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082af8e00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/9883:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082b4b600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082b4b600 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/9884:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082b4ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082b4ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9888:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082b48400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082b48400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/9889:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082b4d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082b4d400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/9891:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082afac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082afac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9894:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888082b4a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888082b4a200 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9899:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880546eca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880546eca00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9905:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880546e8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880546e8400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/9906:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803fe01800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803fe01800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/9911:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff88803fe00400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff88803fe00400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.2/9912:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880546e9800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880546e9800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.4/9930:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888033322c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888033322c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.2/9931:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888083300400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888083300400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.3/9937:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888033326800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888033326800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.0/9938:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff888033325400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff888033325400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.1/9939:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880874e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880874e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
2 locks held by syz-executor.5/9940:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: get_signal+0x1c02/0x25b0 kernel/signal.c:2862
#1: ffff8880874e0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#1: ffff8880874e0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: ext4_buffered_write_iter+0xb0/0x460 fs/ext4/file.c:283
3 locks held by syz-executor.4/9942:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff8880546eb600 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff8880546eb600 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff888033322c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff888033322c00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316
3 locks held by syz-executor.1/9943:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff888082aeb600 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff888082aeb600 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff8880874e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff8880874e6800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316
3 locks held by syz-executor.3/9945:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff88803444e800 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff88803444e800 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff888033326800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff888033326800 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316
3 locks held by syz-executor.0/9948:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff8880546eac00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff8880546eac00 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff888033325400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff888033325400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316
3 locks held by syz-executor.5/9949:
#0: ffff88802c31c460 (sb_writers#4){.+.+}-{0:0}, at: do_unlinkat+0x190/0x680 fs/namei.c:4374
#1: ffff888082aec000 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:810 [inline]
#1: ffff888082aec000 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x280/0x680 fs/namei.c:4378
#2: ffff8880874e0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:775 [inline]
#2: ffff8880874e0400 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xd9/0x930 fs/namei.c:4316

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xe16/0x1090 kernel/hung_task.c:379
kthread+0x344/0x440 kernel/kthread.c:379
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 68 Comm: kworker/u4:4 Not tainted 6.4.0-rc6-syzkaller-00049-g62d8779610bb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: phy90 ieee80211_iface_work
RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3740 [inline]
RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3760 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3815 [inline]
RIP: 0010:__lock_acquire+0x19cb/0x5f30 kernel/locking/lockdep.c:5088
Code: 08 49 c1 ec 2f 84 c0 4e 8d 2c e5 60 2c 41 91 0f 84 c2 03 00 00 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 80 3c 02 00 <0f> 85 53 3d 00 00 4a 8b 1c e5 60 2c 41 91 48 85 db 74 63 48 83 eb
RSP: 0018:ffffc900020af840 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff81659797
RDX: 1ffffffff228d43e RSI: 0000000000000008 RDI: ffffffff9152ad00
RBP: ffff888019af8000 R08: 0000000000000000 R09: ffffffff9152ad07
R10: fffffbfff22a55a0 R11: 0000000000094001 R12: 000000000000aeb2
R13: ffffffff9146a1f0 R14: 0000000000000000 R15: ffff888019af8b18
FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555556a55848 CR3: 000000002994d000 CR4: 0000000000350ef0
Call Trace:
<NMI>
</NMI>
<TASK>
lock_acquire kernel/locking/lockdep.c:5705 [inline]
lock_acquire+0x1b1/0x520 kernel/locking/lockdep.c:5670
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x3d/0x60 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:1011 [inline]
debug_check_no_obj_freed+0xcb/0x420 lib/debugobjects.c:1054
slab_free_hook mm/slub.c:1756 [inline]
slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1807
slab_free mm/slub.c:3786 [inline]
kmem_cache_free+0xe9/0x480 mm/slub.c:3808
skb_kfree_head net/core/skbuff.c:903 [inline]
skb_kfree_head net/core/skbuff.c:899 [inline]
skb_free_head+0x17f/0x1b0 net/core/skbuff.c:918
skb_release_data+0x598/0x820 net/core/skbuff.c:948
skb_release_all net/core/skbuff.c:1014 [inline]
__kfree_skb net/core/skbuff.c:1028 [inline]
kfree_skb_reason+0x179/0x3c0 net/core/skbuff.c:1064
kfree_skb include/linux/skbuff.h:1236 [inline]
ieee80211_iface_work+0x357/0xd70 net/mac80211/iface.c:1650
process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405
worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552
kthread+0x344/0x440 kernel/kthread.c:379
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>


---
This report is generated by a bot. It may contain errors.
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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:
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(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

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 4853c74bd7ab Merge tag 'parisc-for-6.5-rc7' of git://git.k..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=178eb2efa80000
kernel config: https://syzkaller.appspot.com/x/.config?x=aa796b6080b04102
dashboard link: https://syzkaller.appspot.com/bug?extid=38d04642cea49f3a3d2e
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171242cfa80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17934703a80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/fef982ba26aa/disk-4853c74b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/633875549882/vmlinux-4853c74b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a1d2d81c82f6/bzImage-4853c74b.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/45ecbb86ca49/mount_4.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+38d046...@syzkaller.appspotmail.com

INFO: task syz-executor359:5018 blocked for more than 143 seconds.
Not tainted 6.5.0-rc6-syzkaller-00036-g4853c74bd7ab #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz-executor359 state:D stack:27216 pid:5018 ppid:5015 flags:0x00004002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5381 [inline]
__schedule+0xee1/0x59f0 kernel/sched/core.c:6710
schedule+0xe7/0x1b0 kernel/sched/core.c:6786
wb_wait_for_completion+0x1ae/0x270 fs/fs-writeback.c:192
__writeback_inodes_sb_nr+0x1d8/0x270 fs/fs-writeback.c:2650
sync_filesystem fs/sync.c:54 [inline]
sync_filesystem+0xb6/0x280 fs/sync.c:30
generic_shutdown_super+0x74/0x480 fs/super.c:472
kill_block_super+0x64/0xb0 fs/super.c:1417
deactivate_locked_super+0x9a/0x170 fs/super.c:330
deactivate_super+0xde/0x100 fs/super.c:361
cleanup_mnt+0x222/0x3d0 fs/namespace.c:1254
task_work_run+0x14d/0x240 kernel/task_work.c:179
ptrace_notify+0x10c/0x130 kernel/signal.c:2376
ptrace_report_syscall include/linux/ptrace.h:411 [inline]
ptrace_report_syscall_exit include/linux/ptrace.h:473 [inline]
syscall_exit_work kernel/entry/common.c:252 [inline]
syscall_exit_to_user_mode_prepare+0x120/0x220 kernel/entry/common.c:279
__syscall_exit_to_user_mode_work kernel/entry/common.c:284 [inline]
syscall_exit_to_user_mode+0xd/0x50 kernel/entry/common.c:297
do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f497ef65487
RSP: 002b:00007ffdd57d4148 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f497ef65487
RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffdd57d4200
RBP: 00007ffdd57d4200 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffdd57d5270
R13: 00005555566da6c0 R14: 431bde82d7b634db R15: 00007ffdd57d5290

</TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/13:

#0: ffffffff8c9a67f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x2c/0xe20 kernel/rcu/tasks.h:522

1 lock held by rcu_tasks_trace/14:

#0: ffffffff8c9a64f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x2c/0xe20 kernel/rcu/tasks.h:522
1 lock held by khungtaskd/27:
#0: ffffffff8c9a7400 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6615
3 locks held by kworker/u4:2/34:
2 locks held by getty/4774:
#0: ffff88802cdfa098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900015c02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfcb/0x1480 drivers/tty/n_tty.c:2187
1 lock held by syz-executor359/5018:
#0: ffff88807b0e80e0 (&type->s_umount_key#42){+.+.}-{3:3}, at: deactivate_super+0xd6/0x100 fs/super.c:360

=============================================

NMI backtrace for cpu 1

CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.5.0-rc6-syzkaller-00036-g4853c74bd7ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023

Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]

dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x2ac/0x310 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf29/0x11b0 kernel/hung_task.c:379
kthread+0x33a/0x430 kernel/kthread.c:389
ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0

CPU: 0 PID: 34 Comm: kworker/u4:2 Not tainted 6.5.0-rc6-syzkaller-00036-g4853c74bd7ab #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:200
Code: a6 27 99 02 66 0f 1f 44 00 00 f3 0f 1e fa 48 8b be b0 01 00 00 e8 b0 ff ff ff 31 c0 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 <f3> 0f 1e fa 65 8b 05 dd b0 7d 7e 89 c1 48 8b 34 24 81 e1 00 01 00
RSP: 0018:ffffc90000ab74e8 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffea0001c90174 RCX: ffffffff81fa92f9
RDX: ffff8880136fbb80 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000003 R11: 1ffffffff1936441 R12: 0000000000000003
R13: 0000000000000200 R14: 0000000000000003 R15: ffffea0001c90140

FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 000055fded888928 CR3: 0000000028191000 CR4: 0000000000350ef0

Call Trace:
<NMI>
</NMI>
<TASK>

instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1375 [inline]
page_ref_dec_and_test include/linux/page_ref.h:210 [inline]
put_page_testzero include/linux/mm.h:1028 [inline]
folio_put_testzero include/linux/mm.h:1033 [inline]
folio_put include/linux/mm.h:1439 [inline]
grow_dev_page fs/buffer.c:1093 [inline]
grow_buffers fs/buffer.c:1123 [inline]
__getblk_slow+0x4b7/0x720 fs/buffer.c:1150
__getblk_gfp fs/buffer.c:1445 [inline]
__bread_gfp+0x215/0x310 fs/buffer.c:1479
sb_bread include/linux/buffer_head.h:351 [inline]
exfat_get_dentry_set+0x283/0xc10 fs/exfat/dir.c:878
__exfat_write_inode+0x2c0/0x9e0 fs/exfat/inode.c:45
exfat_write_inode+0xad/0x130 fs/exfat/inode.c:94
write_inode fs/fs-writeback.c:1456 [inline]
__writeback_single_inode+0xa81/0xe70 fs/fs-writeback.c:1668
writeback_sb_inodes+0x599/0x1010 fs/fs-writeback.c:1894
wb_writeback+0x2a5/0xa90 fs/fs-writeback.c:2070
wb_do_writeback fs/fs-writeback.c:2217 [inline]
wb_workfn+0x29c/0xfd0 fs/fs-writeback.c:2257
process_one_work+0xaa2/0x16f0 kernel/workqueue.c:2600
worker_thread+0x687/0x1110 kernel/workqueue.c:2751
kthread+0x33a/0x430 kernel/kthread.c:389
ret_from_fork+0x2c/0x70 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.463 msecs


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[syzbot]

syzbot has bisected this issue to:

commit 5904de0d735bbb3b4afe9375c5b4f9748f882945
Author: Chen Yu <yu.c...@intel.com>
Date: Fri Apr 14 12:10:42 2023 +0000

PM: hibernate: Do not get block device exclusively in test_resume mode

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1275be4ba80000
start commit: 4853c74bd7ab Merge tag 'parisc-for-6.5-rc7' of git://git.k..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=1175be4ba80000
console output: https://syzkaller.appspot.com/x/log.txt?x=1675be4ba80000

kernel config: https://syzkaller.appspot.com/x/.config?x=aa796b6080b04102
dashboard link: https://syzkaller.appspot.com/bug?extid=38d04642cea49f3a3d2e

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171242cfa80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17934703a80000

Reported-by: syzbot+38d046...@syzkaller.appspotmail.com
Fixes: 5904de0d735b ("PM: hibernate: Do not get block device exclusively in test_resume mode")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Chen Yu]

Hi,

Thanks for reporting this, the commit has set the exclusive open mode incorrectly
for non-snapshot_test mode, I'll post a fix patch.

thanks,
Chenyu