syzbot


BUG: scheduling while atomic in exit_to_user_mode_loop

Status: upstream: reported syz repro on 2022/10/09 05:55
Reported-by: syzbot+cceb1394467dba9c62d9@syzkaller.appspotmail.com
First crash: 59d, last: 28d

Cause bisection: failed (bisect log)

Sample crash report:
ntfs3: loop2: Different NTFS' sector size (1024) and media sector size (512)
BUG: scheduling while atomic: syz-executor.2/9901/0x00000002
2 locks held by syz-executor.2/9901:
 #0: ffff888075f880e0 (&type->s_umount_key#47/1){+.+.}-{3:3}, at: alloc_super+0x212/0x920 fs/super.c:228
 #1: ffff8880678e78f0 (&sb->s_type->i_lock_key#33){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline]
 #1: ffff8880678e78f0 (&sb->s_type->i_lock_key#33){+.+.}-{2:2}, at: _atomic_dec_and_lock+0x9d/0x110 lib/dec_and_lock.c:28
Modules linked in:
Preemption disabled at:
[<0000000000000000>] 0x0
Kernel panic - not syncing: scheduling while atomic
CPU: 1 PID: 9901 Comm: syz-executor.2 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 panic+0x2d6/0x715 kernel/panic.c:274
 __schedule_bug+0x1ff/0x250 kernel/sched/core.c:5725
 schedule_debug+0x1d3/0x3c0 kernel/sched/core.c:5754
 __schedule+0xfb/0xdf0 kernel/sched/core.c:6389
 schedule+0xcb/0x190 kernel/sched/core.c:6571
 exit_to_user_mode_loop+0xe5/0x150 kernel/entry/common.c:157
 exit_to_user_mode_prepare+0xb2/0x140 kernel/entry/common.c:201
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 000f:lock_acquire+0x1e1/0x3c0
RSP: 0018:ffffc9000563f900 EFLAGS: 00000206
RAX: 1ffff92000ac7f28 RBX: 0000000000000001 RCX: ffff8880753be2f0
RDX: dffffc0000000000 RSI: ffffffff8a8d9060 RDI: ffffffff8aecb5e0
RBP: ffffc9000563fa28 R08: dffffc0000000000 R09: fffffbfff1fc4229
R10: fffffbfff1fc4229 R11: 1ffffffff1fc4228 R12: dffffc0000000000
R13: 1ffff92000ac7f24 R14: ffffc9000563f940 R15: 0000000000000246
 </TASK>
Kernel Offset: disabled
Rebooting in 86400 seconds..

Fix bisection attempts:
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-fs 2022/11/05 09:45 upstream b208b9fbbcba 267e3bb1 .config log report syz
* Struck through repros no longer work on HEAD.
Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-fs 2022/10/05 05:48 upstream 0326074ff465 267e3bb1 .config log report syz BUG: scheduling while atomic in exit_to_user_mode_loop
* Struck through repros no longer work on HEAD.