uvm_fault: _rb_remove

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fd49698d88e5 Add support for RK3576 clocks and resets. A c..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1429ef5a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=230923220bfd54de985e

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c159f2fe1cb1/disk-fd49698d.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/d321f1e712d8/bsd-fd49698d.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0df89642a17a/kernel-fd49698d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+230923...@syzkaller.appspotmail.com

uvm_fault(0xfffffd806ccf4a20, 0x7d488207c18, 0, 1) -> e
kernel: page fault trap, code=0
Stopped at _rb_remove+0x5a8: movl 0x18(%r15),%r14d
TID PID UID PRFLAGS PFLAGS CPU COMMAND
*325158 12468 0 0 0x4000000 0 syz-executor
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove_color sys/kern/subr_tree.c:271 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove sys/kern/subr_tree.c:384 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 sys/kern/subr_tree.c:395
brelse(fffffd800e003030) at brelse+0x2f9 sys/kern/vfs_bio.c:891
vinvalbuf(fffffd8064a5e5e8,2,fffffd8007ffd410,ffff8000338d7250,0,ffffffffffffffff) at vinvalbuf+0x539 sys/kern/vfs_subr.c:1997
ffs_truncate(fffffd806c929900,0,4,fffffd8007ffd410) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1
ffs_write(ffff80003c9d3b80) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401
VOP_WRITE(fffffd8064a5e5e8,ffff80003c9d3d38,7,fffffd8007ffd410) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806cc2f088,ffff80003c9d3d38,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff8000338d7250,3,ffff80003c9d3d38,0,ffff80003c9d3de0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff8000338d7250,ffff80003c9d3e90,ffff80003c9d3de0) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80003c9d3e90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c9d3e90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd40f1cc9d90, count: 4
https://www.openbsd.org/ddb.html describes the minimum info required in bug
reports. Insufficient info makes it difficult to find and fix bugs.
ddb>
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
*cpu0: uvm_fault(0xfffffd806ccf4a20, 0x7d488207c18, 0, 1) -> e
ddb> trace
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove_color sys/kern/subr_tree.c:271 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove sys/kern/subr_tree.c:384 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 sys/kern/subr_tree.c:395
brelse(fffffd800e003030) at brelse+0x2f9 sys/kern/vfs_bio.c:891
vinvalbuf(fffffd8064a5e5e8,2,fffffd8007ffd410,ffff8000338d7250,0,ffffffffffffffff) at vinvalbuf+0x539 sys/kern/vfs_subr.c:1997
ffs_truncate(fffffd806c929900,0,4,fffffd8007ffd410) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1
ffs_write(ffff80003c9d3b80) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401
VOP_WRITE(fffffd8064a5e5e8,ffff80003c9d3d38,7,fffffd8007ffd410) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806cc2f088,ffff80003c9d3d38,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff8000338d7250,3,ffff80003c9d3d38,0,ffff80003c9d3de0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff8000338d7250,ffff80003c9d3e90,ffff80003c9d3de0) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80003c9d3e90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c9d3e90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd40f1cc9d90, count: -11
ddb> show registers
rdi 0x1
rsi 0x80000 acpi_pdirpa+0x6be71
rbp 0xffff80003c9d37a0
rbx 0xfffffd806c36d258
rdx 0xffff8000016b3e00
rcx 0xfffffd800e003030
rax 0x7ffff acpi_pdirpa+0x6be70
r8 0
r9 0xffffffffffffffff
r10 0
r11 0xadb2317816258ffb
r12 0xfffffd8077cf8690
r13 0xffffffff8360f000 buf_rb_bufs_RBT_INFO
r14 0x83871000 __kernel_virt_to_phys+0x3871000
r15 0x7d488207c00
rip 0xffffffff81adad18 _rb_remove+0x5a8
cs 0x8
rflags 0x10206 __ALIGN_SIZE+0xf206
rsp 0xffff80003c9d3720
ss 0
_rb_remove+0x5a8: movl 0x18(%r15),%r14d
ddb> show proc
PROC (syz-executor) tid=325158 pid=12468 tcnt=5 stat=onproc
flags process=0 proc=4000000<THREAD>
runpri=17, usrpri=83, slppri=17, nice=20
wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0
forw=0xffffffffffffffff, list=0xffff80003a8f6d28,0xffff8000338d6d30
process=0xffff80002a7b3190 user=0xffff80003c9ce000, vmspace=0xfffffd806ccf4a20
estcpu=33, cpticks=3, pctcpu=0.1, user=0, sys=3, intr=0
ddb> ps
PID TID PPID UID S FLAGS WAIT COMMAND
32836 465887 13957 0 3 0x80 nanoslp syz-executor
32836 506995 13957 0 3 0x4000080 rest syz-executor
32836 232673 13957 0 3 0x4000080 fsleep syz-executor
92831 198495 89460 0 2 0 syz-executor
92831 48127 89460 0 2 0x4000000 syz-executor
93547 268010 71319 0 2 0 syz-executor
93547 143590 71319 0 3 0x4000080 fsleep syz-executor
83527 476531 3064 0 2 0 syz-executor
83527 511335 3064 0 3 0x4000080 fsleep syz-executor
83527 524165 3064 0 3 0x4000080 fsleep syz-executor
12468 159230 95967 0 3 0x80 nanoslp syz-executor
*12468 325158 95967 0 7 0x4000000 syz-executor
12468 312909 95967 0 3 0x4000000 inode syz-executor
12468 35036 95967 0 3 0x4000000 inode syz-executor
12468 268765 95967 0 3 0x4000080 fsleep syz-executor
95967 240994 70442 0 3 0x82 nanoslp syz-executor
43881 240421 0 0 3 0x14280 nfsidl nfsio
92669 390809 0 0 3 0x14280 nfsidl nfsio
71780 336568 0 0 3 0x14280 nfsidl nfsio
10310 62308 0 0 3 0x14280 nfsidl nfsio
42543 152160 0 0 3 0x14280 nfsidl nfsio
99207 419691 0 0 3 0x14280 nfsidl nfsio
9874 132895 0 0 3 0x14280 nfsidl nfsio
48487 181349 0 0 3 0x14280 nfsidl nfsio
12347 77438 0 0 3 0x14280 nfsidl nfsio
46600 356534 0 0 3 0x14280 nfsidl nfsio
52979 444609 0 0 3 0x14280 nfsidl nfsio
23253 404265 0 0 3 0x14280 nfsidl nfsio
68006 339922 0 0 3 0x14280 nfsidl nfsio
96100 341024 0 0 3 0x14280 nfsidl nfsio
22819 377222 0 0 3 0x14280 nfsidl nfsio
3999 339575 0 0 3 0x14280 nfsidl nfsio
74033 412832 0 0 3 0x14280 nfsidl nfsio
8623 117050 0 0 3 0x14280 nfsidl nfsio
70457 400620 0 0 3 0x14280 nfsidl nfsio
18783 509269 0 0 3 0x14280 nfsidl nfsio
34128 296887 0 0 3 0x14200 acct acct
85708 126791 1 0 3 0x100083 ttyopn getty
89460 510847 70442 0 2 0xc82 syz-executor
73585 223107 70442 0 3 0x82 piperd syz-executor
47380 510194 70442 0 3 0x82 wait syz-executor
3064 137383 70442 0 3 0x82 nanoslp syz-executor
62229 424674 70442 0 2 0x2 syz-executor
13957 276192 70442 0 3 0x82 nanoslp syz-executor
71319 132704 70442 0 3 0x82 nanoslp syz-executor
70442 487547 20686 0 3 0x82 nanoslp syz-executor
20686 239220 86109 0 3 0x10008a sigsusp ksh
86109 207871 41974 0 3 0x98 kqread sshd-session
41974 372612 40756 0 3 0x92 kqread sshd-session
40756 86816 1 0 3 0x88 kqread sshd
3443 260373 12771 73 3 0x1100090 kqread syslogd
12771 363761 1 0 3 0x100082 sbwait syslogd
83734 230871 1 0 3 0x100080 kqread resolvd
94288 449875 22594 77 3 0x100092 kqread dhcpleased
38067 164703 22594 77 3 0x100092 kqread dhcpleased
22594 346355 1 0 3 0x80 kqread dhcpleased
65353 57341 0 0 3 0x14200 bored smr
46831 275804 0 0 2 0x14200 zerothread
4245 225657 0 0 3 0x14200 aiodoned aiodoned
93506 477356 0 0 3 0x14200 syncer update
20635 246704 0 0 3 0x14200 cleaner cleaner
70079 170820 0 0 3 0x14200 reaper reaper
20007 276880 0 0 3 0x14200 pgdaemon pagedaemon
77621 162403 0 0 3 0x14200 bored viomb
85866 341436 0 0 3 0x40014200 acpi0 acpi0
93003 255004 0 0 2 0x14200 softnet0
59719 319059 0 0 3 0x14200 bored systqmp
86897 75377 0 0 3 0x14200 bored systq
83485 476074 0 0 3 0x40014200 tmoslp softclock
9033 509255 0 0 3 0x40014200 idle0
1 344360 0 0 3 0x82 wait init
0 0 -1 0 3 0x10010200 scheduler swapper
ddb> show all locks
No such command
ddb> show malloc
Type InUse MemUse HighUse Limit Requests Type Lim
devbuf 11056 12250K 12733K 166960K 13752 0
pcb 17 17K 19K 166960K 295 0
rtable 237 10K 11K 166960K 638 0
pf 31 13K 17K 166960K 131 0
ifaddr 38 7K 8K 166960K 94 0
ifgroup 43 1K 2K 166960K 148 0
sysctl 4 1K 9K 166960K 29 0
counters 32 17K 18K 166960K 116 0
ioctlops 0 0K 8K 166960K 432 0
iov 0 0K 16K 166960K 80 0
mount 1 1K 1K 166960K 1 0
log 0 0K 0K 166960K 4 0
vnodes 1411 89K 89K 166960K 2615 0
UFS quota 1 32K 32K 166960K 1 0
UFS mount 5 36K 36K 166960K 5 0
shm 2 1K 5K 166960K 4 0
VM map 2 1K 1K 166960K 2 0
sem 12 0K 1K 166960K 95 0
dirhash 12 2K 2K 166960K 30 0
ACPI 1692 195K 286K 166960K 12470 0
file desc 16 57K 85K 166960K 1025 0
sigio 0 0K 0K 166960K 19 0
proc 60 59K 91K 166960K 624 0
subproc 72 4K 4K 166960K 81 0
NFS srvsock 1 0K 0K 166960K 1 0
NFS daemon 1 16K 16K 166960K 1 0
ip_moptions 0 0K 0K 166960K 75 0
in_multi 88 6K 7K 166960K 146 0
ether_multi 1 0K 0K 166960K 7 0
mrt 0 0K 0K 166960K 17 0
ISOFS mount 1 32K 32K 166960K 1 0
MSDOSFS mount 1 16K 16K 166960K 1 0
ttys 91 413K 413K 166960K 91 0
exec 0 0K 1K 166960K 500 0
fusefs mount 1 32K 32K 166960K 1 0
pfkey data 0 0K 0K 166960K 1 0
tdb 3 0K 0K 166960K 3 0
VM swap 8 62K 64K 166960K 10 0
UVM amap 215 143K 158K 166960K 10860 0
UVM aobj 33 14K 14K 166960K 35 0
pinsyscall 37 74K 92K 166960K 2149 0
memdesc 1 4K 4K 166960K 1 0
crypto data 1 1K 1K 166960K 1 0
ip6_options 0 0K 1K 166960K 53 0
NDP 10 0K 1K 166960K 63 0
temp 80 9076K 9141K 166960K 33266 0
kqueue 15 24K 34K 166960K 213 0
SYN cache 2 16K 16K 166960K 2 0
ddb> show all pools
Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle
rtpcb 120 129 0 126 1 0 1 1 0 8 0
rtentry 136 160 0 67 4 0 4 4 0 8 0
unpcb 144 657 0 640 4 3 1 4 0 8 0
syncache 336 3 0 3 1 1 0 1 0 8 0
tcpqe 32 8 0 8 1 1 0 1 0 8 0
tcpcb 736 244 0 239 1 0 1 1 0 8 0
arp 96 22 0 5 1 0 1 1 0 8 0
ipq 40 7 0 1 1 0 1 1 0 8 0
ipqe 40 13 0 4 1 0 1 1 0 8 0
inpcb 328 1164 0 1155 19 17 2 12 0 8 1
ip6q 72 7 0 2 1 0 1 1 0 8 0
ip6af 40 12 0 6 1 0 1 1 0 8 0
nd6 112 39 0 19 1 0 1 1 0 8 0
pkpcb 40 5 0 5 1 1 0 1 0 8 0
kcovpl 48 9 0 1 1 0 1 1 0 8 0
mppekey 1024 2 0 2 1 1 0 1 0 8 0
ppxss 1072 70 0 70 3 3 0 1 0 8 0
pppxif 1384 7 0 7 1 1 0 1 0 8 0
pfstscr 40 4 0 4 1 1 0 1 0 8 0
pfrktable 1344 1 0 1 1 1 0 1 0 8 0
pfstlim 224 1 0 1 1 1 0 1 0 8 0
pfanchor 1288 3 0 3 1 1 0 1 0 8 0
pftag 88 1 0 0 1 0 1 1 0 8 0
pfqueue 320 1 0 0 1 0 1 1 0 8 0
pfstitem 24 2 0 0 1 0 1 1 0 8 0
pfstkey 128 10 0 8 2 1 1 1 0 8 0
pfstate 384 5 0 4 2 1 1 1 0 8 0
pfrule 1360 6 0 6 2 2 0 1 0 8 0
art_heap8 4096 4 0 0 4 0 4 4 0 8 0
art_heap4 256 648 0 228 30 3 27 30 0 8 0
art_table 40 652 0 228 5 0 5 5 0 8 0
art_node 32 158 0 74 1 0 1 1 0 8 0
sysvmsgpl 40 20 0 14 1 0 1 1 0 8 0
semupl 112 2 0 2 1 1 0 1 0 8 0
semapl 112 91 0 81 1 0 1 1 0 8 0
shmpl 112 27 0 1 1 0 1 1 0 8 0
dirhash 1024 29 0 12 3 0 3 3 0 8 0
dino2pl 256 3568 0 2119 92 0 92 92 0 8 0
ffsino 256 3569 0 2119 92 0 92 92 0 8 0
nchpl 144 5041 0 3344 64 0 64 64 0 8 0
rtmask 32 7 0 7 1 1 0 1 0 8 0
vnodes 216 4262 0 0 237 0 237 237 0 8 0
namei 1024 17044 0 17041 2 1 1 1 0 8 0
vcpupl 3904 5 0 1 1 0 1 1 0 8 0
vmpool 808 5 0 1 1 0 1 1 0 8 0
kstatmem 264 88 0 68 3 1 2 3 0 8 0
scsiplug 72 4 0 4 1 1 0 1 0 8 0
scxspl 216 21661 0 21661 8 7 1 8 1 8 1
plimitpl 152 419 0 401 1 0 1 1 0 8 0
sigapl 424 1340 0 1278 8 0 8 8 0 8 0
knotepl 120 52855 0 52566 38 29 9 18 0 8 0
kqueuepl 184 366 0 354 5 4 1 3 0 8 0
pipepl 304 266 0 236 3 0 3 3 0 8 0
fdescpl 448 1305 0 1277 4 0 4 4 0 8 0
filepl 120 8953 0 8729 15 7 8 11 0 8 0
lockfpl 104 324 0 321 1 0 1 1 0 8 0
lockfspl 48 148 0 145 1 0 1 1 0 8 0
sessionpl 144 23 0 15 1 0 1 1 0 8 0
pgrppl 48 41 0 25 1 0 1 1 0 8 0
ucredpl 104 1906 0 1895 1 0 1 1 0 8 0
zombiepl 144 1354 0 1353 1 0 1 1 0 8 0
processpl 1152 1340 0 1278 5 0 5 5 0 8 0
procpl 664 2702 0 2630 7 0 7 7 0 8 0
sosppl 176 11 0 11 3 3 0 1 0 8 0
sockpl 552 1988 0 1959 17 14 3 12 0 8 0
mcl64k 65536 120 0 117 1 0 1 1 0 8 0
mcl16k 16384 3 5 3 1 1 0 1 0 8 0
mcl12k 12288 2 6 2 1 1 0 1 0 8 0
mcl9k 9216 3 1 3 1 1 0 1 0 8 0
mcl8k 8192 19 12 19 1 1 0 1 0 8 0
mcl4k 4096 3665 92 3611 14 7 7 14 0 8 0
mcl2k 2048 1107 0 1097 4 2 2 4 0 8 0
mtagpl 96 62 0 16 2 0 2 2 0 8 0
mbufpl 256 14254 0 14051 21 4 17 21 0 8 0
bufpl 280 7685 0 1467 445 0 445 445 0 8 0
bufpl: pool(0xffffffff839dc9a8:bufpl): page inconsistency: page 0x0; at page head addr 0xfffffd806c36df90 (p 0xfffffd806c36d000)
anonpl 24 199330 0 191365 77 28 49 57 0 187 0
amapchunkpl 152 37235 0 36771 44 21 23 30 0 158 0
amappl16 200 3665 0 3352 34 17 17 17 0 8 0
amappl15 192 3 0 3 1 1 0 1 0 8 0
amappl14 184 424 0 423 1 0 1 1 0 8 0
amappl13 176 115 0 105 1 0 1 1 0 8 0
amappl12 168 1556 0 1529 2 0 2 2 0 8 0
amappl11 160 6 0 6 1 1 0 1 0 8 0
amappl10 152 75 0 65 1 0 1 1 0 8 0
amappl9 144 260 0 259 1 0 1 1 0 8 0
amappl8 136 102 0 101 1 0 1 1 0 8 0
amappl7 128 50 0 48 1 0 1 1 0 8 0
amappl6 120 263 0 252 1 0 1 1 0 8 0
amappl5 112 97 0 90 1 0 1 1 0 8 0
amappl4 104 448 0 414 2 1 1 2 0 8 0
amappl3 96 6295 0 6211 3 0 3 3 0 8 0
amappl2 88 1397 0 1331 2 0 2 2 0 8 0
amappl1 80 12742 0 12211 12 0 12 12 0 8 0
amappl 88 9976 0 9823 5 0 5 5 0 92 0
uvmvnodes 80 133 0 0 3 0 3 3 0 8 0
dma32768 32768 1 0 1 1 1 0 1 0 8 0
dma8192 8192 1 0 1 1 1 0 1 0 8 0
dma4096 4096 1 0 1 1 1 0 1 0 8 0
dma1024 1024 1 0 0 1 0 1 1 0 8 0
dma256 256 6 0 6 1 1 0 1 0 8 0
dma128 128 254 0 254 1 1 0 1 0 8 0
dma64 64 7 0 7 2 1 1 1 0 8 1
dma32 32 7 0 7 1 1 0 1 0 8 0
dma16 16 18 0 17 1 0 1 1 0 8 0
aobjpl 72 34 0 2 1 0 1 1 0 8 0
uaddrrnd 24 1305 0 1277 1 0 1 1 0 8 0
uaddrbest 32 2 0 0 1 0 1 1 0 8 0
uaddr 24 1305 0 1277 1 0 1 1 0 8 0
vmmpekpl 168 11521 0 11472 3 0 3 3 0 8 0
vmmpepl 168 86731 0 84689 105 11 94 94 0 357 0
vmsppl 368 1304 0 1277 4 1 3 4 0 8 0
rwobjpl 40 24159 0 22874 14 0 14 14 0 8 0
pdppl 4096 2626 0 2560 102 31 71 76 0 8 5
pvpl 32 575249 0 561683 188 74 114 133 0 265 1
pmappl 216 1309 0 1278 2 0 2 2 0 8 0
extentpl 40 45 0 27 1 0 1 1 0 8 0
phpool 112 386 0 59 11 0 11 11 0 8 0
ddb> machine ddbcpu 0
No such command
ddb> trace
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove_color sys/kern/subr_tree.c:271 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove sys/kern/subr_tree.c:384 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 sys/kern/subr_tree.c:395
brelse(fffffd800e003030) at brelse+0x2f9 sys/kern/vfs_bio.c:891
vinvalbuf(fffffd8064a5e5e8,2,fffffd8007ffd410,ffff8000338d7250,0,ffffffffffffffff) at vinvalbuf+0x539 sys/kern/vfs_subr.c:1997
ffs_truncate(fffffd806c929900,0,4,fffffd8007ffd410) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1
ffs_write(ffff80003c9d3b80) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401
VOP_WRITE(fffffd8064a5e5e8,ffff80003c9d3d38,7,fffffd8007ffd410) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806cc2f088,ffff80003c9d3d38,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff8000338d7250,3,ffff80003c9d3d38,0,ffff80003c9d3de0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff8000338d7250,ffff80003c9d3e90,ffff80003c9d3de0) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80003c9d3e90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c9d3e90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd40f1cc9d90, count: -11
ddb> machine ddbcpu 1
No such command
ddb> trace
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove_color sys/kern/subr_tree.c:271 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 rbe_remove sys/kern/subr_tree.c:384 [inline]
_rb_remove(ffffffff8360f000,fffffd8064a5e650,fffffd800e003030) at _rb_remove+0x5a8 sys/kern/subr_tree.c:395
brelse(fffffd800e003030) at brelse+0x2f9 sys/kern/vfs_bio.c:891
vinvalbuf(fffffd8064a5e5e8,2,fffffd8007ffd410,ffff8000338d7250,0,ffffffffffffffff) at vinvalbuf+0x539 sys/kern/vfs_subr.c:1997
ffs_truncate(fffffd806c929900,0,4,fffffd8007ffd410) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1
ffs_write(ffff80003c9d3b80) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401
VOP_WRITE(fffffd8064a5e5e8,ffff80003c9d3d38,7,fffffd8007ffd410) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245
vn_write(fffffd806cc2f088,ffff80003c9d3d38,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408
dofilewritev(ffff8000338d7250,3,ffff80003c9d3d38,0,ffff80003c9d3de0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384
sys_write(ffff8000338d7250,ffff80003c9d3e90,ffff80003c9d3de0) at sys_write+0xa2 sys/kern/sys_generic.c:300
syscall(ffff80003c9d3e90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80003c9d3e90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd40f1cc9d90, count: -11


---
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