kern/60922: Crash in ZFS while bulk-building packages

["riz%tastylime.net@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60922
>Category:       kern
>Synopsis:       Crash in ZFS while bulk-building packages
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sat Oct 24 16:50:00 +0000 2026
>Originator:     Jeff Rizzo
>Release:        11.0_STABLE
>Organization:
ACME widgets LLC
>Environment:
NetBSD rambutan.tastylime.net 11.0_STABLE NetBSD 11.0_STABLE (HZ1000) #0: Fri Sep 11 00:47:28 UTC 2026  riz%acai.tastylime.net@localhost:/tank/netbsd/netbsd-11/obj.amd64/sys/arch/amd64/compile/HZ1000 amd64
>Description:
While running a full (well, mostly full) pkgsrc build, the machine crashed and rebooted - and didn't get a full dump, but maybe this backtrace is useful:

[ 3686768.1881689] panic: solaris assert: arc_decompress(buf) == 0 (0x5 == 0x0), file: /usr/src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/arc.c, line: 4962
[ 3686768.1971683] cpu15: Begin traceback...
[ 3686768.1971683] vpanic() at netbsd:vpanic+0x171
[ 3686768.1971683] panic() at netbsd:panic+0x3c
[ 3686768.1971683] arc_read() at zfs:arc_read+0x9da
[ 3686768.1971683] dbuf_read() at zfs:dbuf_read+0x1c4
[ 3686768.1971683] dmu_buf_hold_array_by_dnode() at zfs:dmu_buf_hold_array_by_dnode+0x123
[ 3686768.1971683] dmu_read_uio_dnode() at zfs:dmu_read_uio_dnode+0x40
[ 3686768.1971683] dmu_read_uio_dbuf() at zfs:dmu_read_uio_dbuf+0x42
[ 3686768.1971683] zfs_netbsd_read() at zfs:zfs_netbsd_read+0x5ae
[ 3686768.1971683] layer_bypass() at netbsd:layer_bypass+0xf0
[ 3686768.1971683] VOP_READ() at netbsd:VOP_READ+0x42
[ 3686768.1971683] vn_read() at netbsd:vn_read+0x140
[ 3686768.1971683] dofileread() at netbsd:dofileread+0x79
[ 3686768.1971683] sys_read() at netbsd:sys_read+0x49
[ 3686768.1971683] syscall() at netbsd:syscall+0x9a
[ 3686768.1971683] --- syscall (number 3) ---
[ 3686768.1971683] netbsd:syscall+0x9a:
[ 3686768.1971683] cpu15: End traceback...

[ 3686768.1971683] dumping to dev 168,7 (offset=8, size=50329365):
[ 3686768.1971683] dump WARNING: lwp 789 (system pgdaemon) flags 0x20020020: timecounter went backwards from (3686769 + 0x2a6416514536574e/2^64) sec to (3686768 + 0x43fd8f5669cca0f2/2^64) sec in netbsd:mi_switch+0x64
[ 3686768.1971683] failed: insufficient space (8388608 < 333331666)


[ 3686768.1971683] rebooting...
>How-To-Repeat:
Well, I'm about to resume the build...

>Fix:
none given