------------[ cut here ]------------
read > cnt + 1
WARNING: kernel/trace/ring_buffer.c:762 at ring_buffer_nr_dirty_pages+0x207/0x290 kernel/trace/ring_buffer.c:762, CPU#0: syz.8.4856/31421
Modules linked in:
CPU: 0 UID: 0 PID: 31421 Comm: syz.8.4856 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:ring_buffer_nr_dirty_pages+0x207/0x290 kernel/trace/ring_buffer.c:762
Code: 83 c3 01 48 89 ee 48 89 df e8 65 f4 fb ff 48 39 eb 72 11 31 db eb cc e8 37 fa fb ff 90 0f 0b 90 31 db eb bf e8 2a fa fb ff 90 <0f> 0b 90 31 db eb b2 4c 89 e7 e8 5a e6 68 00 e9 f8 fe ff ff 4c 89
RSP: 0018:ffffc900040af5c0 EFLAGS: 00010087
RAX: 00000000000000e2 RBX: 0000000000000001 RCX: ffffc90011054000
RDX: 0000000000080000 RSI: ffffffff820bf2d6 RDI: ffff88807d019f00
RBP: 0000000000000002 R08: 0000000000000006 R09: 0000000000000001
R10: 0000000000000002 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88813fe95000 R14: ffff88813fe4e0a8 R15: ffff88813fe95000
FS: 00007f4cb80ba6c0(0000) GS:ffff888124397000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3080bff8 CR3: 000000004419e000 CR4: 00000000003526f0
Call Trace:
<TASK>
full_hit kernel/trace/ring_buffer.c:784 [inline]
rb_watermark_hit+0x1f5/0x300 kernel/trace/ring_buffer.c:881
ring_buffer_poll_wait+0x2b2/0x490 kernel/trace/ring_buffer.c:1038
trace_poll kernel/trace/trace.c:5327 [inline]
tracing_buffers_poll+0x1cf/0x250 kernel/trace/trace.c:7079
vfs_poll include/linux/poll.h:82 [inline]
select_poll_one fs/select.c:480 [inline]
do_select+0xd54/0x1850 fs/select.c:536
core_sys_select+0x55b/0xbb0 fs/select.c:677
kern_select+0x1d0/0x280 fs/select.c:729
__do_sys_select fs/select.c:736 [inline]
__se_sys_select fs/select.c:733 [inline]
__x64_sys_select+0xbd/0x160 fs/select.c:733
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x840 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4cb719ce59
Code: ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4cb80ba028 EFLAGS: 00000246 ORIG_RAX: 0000000000000017
RAX: ffffffffffffffda RBX: 00007f4cb7415fa0 RCX: 00007f4cb719ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000a
RBP: 00007f4cb7232d6f R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4cb7416038 R14: 00007f4cb7415fa0 R15: 00007fff59572608
</TASK>