assert "ISSET(bp->b_flags, B_BC)" failed in vfs_bio.c (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 879ea5f6fdb7 Update to reflect support for special keys.
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=12918f42580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7058272de1526588
dashboard link: https://syzkaller.appspot.com/bug?extid=769b6dd090e5fdcccd48

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5cdfa60cfda3/disk-879ea5f6.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/446b64d9feca/bsd-879ea5f6.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7ba09c19069c/kernel-879ea5f6.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+769b6d...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "ISSET(bp->b_flags, B_BC)" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/vfs_bio.c", line 1661
Starting stack trace...
panic(ffffffff833a643d) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff833ea289,ffffffff83436049,67d,ffffffff834531a6) at __assert+0x29 sys/kern/subr_prf.c:-1
bufcache_take(fffffd8075fde378) at bufcache_take+0x2d3 sys/kern/vfs_bio.c:1662
getblk(fffffd806718f648,0,4000,0,ffffffffffffffff) at getblk+0x214 sys/kern/vfs_bio.c:1025
bread(fffffd806718f648,0,4000,ffff80002a3280a0) at bread+0x45 bio_doread sys/kern/vfs_bio.c:418 [inline]
bread(fffffd806718f648,0,4000,ffff80002a3280a0) at bread+0x45 sys/kern/vfs_bio.c:463
ffs_read(ffff80002a328110) at ffs_read+0x325 sys/ufs/ffs/ffs_vnops.c:-1
VOP_READ(fffffd806718f648,ffff80002a3282b8,0,fffffd80097fd618) at VOP_READ+0x101 sys/kern/vfs_vops.c:227
ufs_readdir(ffff80002a328370) at ufs_readdir+0x16d sys/ufs/ufs/ufs_vnops.c:1366
VOP_READDIR(fffffd806718f648,ffff80002a3283f8,fffffd80097fd618,ffff80002a32843c) at VOP_READDIR+0x125 sys/kern/vfs_vops.c:453
sys_getdents(ffff8000ffffd9f8,ffff80002a328590,ffff80002a3284e0) at sys_getdents+0x2df sys/kern/vfs_syscalls.c:3183
syscall(ffff80002a328590) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a328590) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:765
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7585fcfe7490, count: 245
End of stack trace.
syncing disks...


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