bisecting fixing commit since cf256fbcbe347b7d0ff58fe2dfa382a156bd3694
building syzkaller on 95777977ade5226323e35e6e5fa1594327640732
testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217
kernel signature: 4f32a8b72bf9ab8d02542fc77b3df0840a678daa4817194e521dec8d0fbfd3ad
run #0: crashed: WARNING in kill_block_super
run #1: crashed: WARNING in kill_block_super
run #2: crashed: WARNING in corrupted
run #3: crashed: WARNING in efs_kill_sb
run #4: crashed: WARNING in corrupted
run #5: crashed: WARNING in corrupted
run #6: crashed: WARNING in kill_block_super
run #7: crashed: WARNING in corrupted
run #8: crashed: WARNING in efs_kill_sb
run #9: crashed: WARNING in efs_kill_sb
run #10: crashed: WARNING in corrupted
run #11: crashed: WARNING in efs_kill_sb
run #12: crashed: WARNING in kill_block_super
run #13: crashed: WARNING in kill_block_super
run #14: crashed: WARNING in kill_block_super
run #15: crashed: WARNING in kill_block_super
run #16: crashed: WARNING in kill_block_super
run #17: crashed: WARNING in kill_block_super
run #18: crashed: WARNING in efs_kill_sb
run #19: crashed: WARNING in kill_block_super
testing current HEAD 7d7d1c0ab3eb7c8d8f63a126535018007823b207
testing commit 7d7d1c0ab3eb7c8d8f63a126535018007823b207 with gcc (GCC) 8.4.1 20210217
kernel signature: 135345e0d4efc21dc3cc58c8b4402cb31214ce32b8e0c947a3c1049e239244e4
run #0: crashed: WARNING in kill_block_super
run #1: crashed: WARNING in kill_block_super
run #2: crashed: WARNING in kill_block_super
run #3: crashed: WARNING in kill_block_super
run #4: crashed: WARNING in corrupted
run #5: crashed: WARNING in kill_block_super
run #6: crashed: WARNING in corrupted
run #7: crashed: WARNING in kill_block_super
run #8: crashed: WARNING in corrupted
run #9: crashed: WARNING in kill_block_super
revisions tested: 2, total time: 24m27.764687078s (build: 17m11.137446071s, test: 6m41.947686387s)
the crash still happens on HEAD
commit msg: Linux 4.14.232
crash: WARNING in kill_block_super
RDX: 0000000020000140 RSI: 0000000020000180 RDI: 00007f1c7c1a4000
RBP: 00007f1c7c1a4040 R08: 00007f1c7c1a4040 R09: 0000000020000140
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000140
R13: 0000000020000180 R14: 00007f1c7c1a4000 R15: 00000000200004c0
------------[ cut here ]------------
WARNING: CPU: 1 PID: 9883 at fs/super.c:1163 kill_block_super+0xba/0xe0 fs/super.c:1165
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 9883 Comm: syz-executor.5 Not tainted 4.14.232-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x14b/0x1e7 lib/dump_stack.c:58
 panic+0x1b0/0x358 kernel/panic.c:183
 __warn.cold.7+0x25/0x25 kernel/panic.c:547
 report_bug+0x1a1/0x200 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x1bd/0x310 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:kill_block_super+0xba/0xe0 fs/super.c:1163
RSP: 0018:ffff88808849fb50 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888094364640 RCX: 1ffff1101205acde
RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8880902d65e8
RBP: ffff88808849fb68 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000050 R11: ffff8880949603c0 R12: ffff8880902d6240
R13: 0000000000000000 R14: ffff888094364640 R15: fffffffffffffff4
 efs_kill_sb+0x37/0x50 fs/efs/super.c:33
 deactivate_locked_super+0x62/0xb0 fs/super.c:319
 sget_userns+0x8eb/0xb40 fs/super.c:537
 sget+0xbe/0x100 fs/super.c:572
 mount_bdev+0xc9/0x330 fs/super.c:1107
 efs_mount+0x10/0x20 fs/efs/super.c:27
 mount_fs+0x7f/0x270 fs/super.c:1237
 vfs_kern_mount.part.9+0x58/0x3c0 fs/namespace.c:1046
 vfs_kern_mount fs/namespace.c:1036 [inline]
 do_new_mount fs/namespace.c:2549 [inline]
 do_mount+0x352/0x2af0 fs/namespace.c:2879
 SYSC_mount fs/namespace.c:3095 [inline]
 SyS_mount+0xb1/0xd0 fs/namespace.c:3072
 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x46797a
RSP: 002b:00007f1c7c1a3fa8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000480 RCX: 000000000046797a
RDX: 0000000020000140 RSI: 0000000020000180 RDI: 00007f1c7c1a4000
RBP: 00007f1c7c1a4040 R08: 00007f1c7c1a4040 R09: 0000000020000140
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000020000140
R13: 0000000020000180 R14: 00007f1c7c1a4000 R15: 00000000200004c0
Kernel Offset: disabled
Rebooting in 86400 seconds..