hi, On Mon, Mar 2, 2026 at 8:19 PM J. Hannken-Illjes <[email protected]> wrote: > > > On 1. Mar 2026, at 15:13, Takashi YAMAMOTO <[email protected]> wrote: > > > > On Fri, Feb 20, 2026 at 5:09 PM Takashi YAMAMOTO <[email protected]> wrote: > >> > >> hi, > >> > >> recently i have used netbsd zfs and have a few questions. > >> > >> * what's the purpose of zfs_zget_cleaner/VN_RELE_CLEANER? > >> i have read the explanation in > >> https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=59885 . > >> but i don't understand why we want to avoid the normal zfs_zget in > >> the first place. > >> for me, it seems working w/o these special versions of functions: > >> > >> https://github.com/yamt/netbsd-src/commit/438ec29437465e0b7e2b831d4452159f83cad0cf > >> (i will attach the same patch to this mail for those who don't like > >> github.) > > > > this version had a few deadlock issues. > > > > i will attach a fixed version i'm currently testing. > > > >> > >> * is anyone using zfs in netbsd seriously? :-) > >> > >> * does anyone have a plan to update the codebase to recent openzfs? > > <a.diff> > > This patch makes the situation better but it fires assertions during unmount. > > Running some stress tests on a 16-core amd64 vm with DEBUG+LOCKDEBUG and > kern.maxvnodes=1105 unmount crashes as it tries to load a vnode during > unmount: > > > panic: kernel diagnostic assertion "mp == NULL || (mp->mnt_iflag & > IMNT_UNMOUNT) == 0 || vp->v_tag == VT_VFS" failed: file > "src/sys/kern/vfs_mount.c", line 545 > > #12 vfs_insmntque (vp=0xffffb751d4324a80, mp=0xffffb751cf2e2000) at > src/sys/kern/vfs_mount.c:545 > #13 vcache_get (mp=0xffffb751cf2e2000, key=key@entry=0xffffc3070a334bc8, > key_len=key_len@entry=8, vpp=vpp@entry=0xffffc3070a334bd8) at > src/sys/kern/vfs_vnode.c:1666 > #14 zfs_zget (zfsvfs=zfsvfs@entry=0xffffc3002f7ba000, obj_num=<optimized > out>, obj_num@entry=24865, zpp=zpp@entry=0xffffc3070a334c20) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_znode.c:1287 > #15 zfs_get_data (arg=0xffffc3002f7ba000, lr=0xffffc30048cd41d8, > buf=0xffffc30048cd4298 "", zio=0xffffb751e587e840) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vnops.c:1500 > #16 zil_lwb_commit (zilog=<optimized out>, itx=0xffffb7517fb6f5c0, > lwb=0xffffb751bffa25f8) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zil.c:1144 > #17 zil_commit_writer (zilog=0xffffb751e664d540) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zil.c:1556 > #18 zil_commit (zilog=0xffffb751e664d540, foid=<optimized out>) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zil.c:1638 > #19 zil_commit (zilog=0xffffb751e664d540, foid=0) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zil.c:1620 > #20 zil_close (zilog=0xffffb751e664d540) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zil.c:1856 > #21 zfsvfs_teardown (zfsvfs=zfsvfs@entry=0xffffc3002f7ba000, > unmounting=unmounting@entry=1) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c:2288 > #22 zfs_umount (vfsp=0xffffb751cf2e2000, fflag=524288) at > src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c:2445 > #23 VFS_UNMOUNT (mp=mp@entry=0xffffb751cf2e2000, a=a@entry=524288) at > src/sys/kern/vfs_subr.c:1526 > #24 dounmount (mp=mp@entry=0xffffb751cf2e2000, flags=524288, > l=l@entry=0xffffb751e855d800) at src/sys/kern/vfs_mount.c:980 > #25 sys_unmount (l=0xffffb751e855d800, uap=0xffffc3070a335000, > retval=<optimized out>) at src/sys/kern/vfs_syscalls.c:728 > #26 sy_call (sy=0xffffffff8210a050 <sysent+528>, l=0xffffb751e855d800, > uap=0xffffc3070a335000, rval=0xffffc3070a334fb0) at > src/sys/sys/syscallvar.h:65 > #27 sy_invoke (sy=0xffffffff8210a050 <sysent+528>, l=0xffffb751e855d800, > uap=0xffffc3070a335000, rval=0xffffc3070a334fb0, code=22) at > src/sys/sys/syscallvar.h:94 > #28 syscall (frame=0xffffc3070a335000) at src/sys/arch/x86/x86/syscall.c:137 > #29 handle_syscall () > > Here we have mp != NULL and mp->mnt_iflag == 0x122 (IMNT_MPSAFE | > IMNT_NCLOOKUP | IMNT_UNMOUNT)
it's an interesting crash. thank you.
i tried to reproduce it by myself. but no luck.
the attached patch (b.diff) would fix it.
well, honestly speaking, i don't understand why zil_close commits the
zil in the first place.
my impression is that it should not be necessary because we are
syncing txg for unmount anyway.
what do you think?
>
>
> Disabling this assertion zfs unmount fails to destroy a list as it is not
> empty:
>
>
> panic: solaris assert: list->list_head.list_next == node, file:
> src/sys/../external/cddl/osnet/dist/uts/common/os/list.c, line: 86
>
> #12 list_destroy (list=list@entry=0xffff940059153040) at
> src/sys/../external/cddl/osnet/dist/uts/common/os/list.c:86
> #13 zfsvfs_free (zfsvfs=0xffff940059152000) at
> src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c:1439
> #14 zfs_freevfs (vfsp=0xffff859a2e81d000) at
> src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c:2782
> #15 zfs_umount (vfsp=0xffff859a2e81d000, fflag=<optimized out>) at
> src/sys/../external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c:2471
> #16 VFS_UNMOUNT (mp=mp@entry=0xffff859a2e81d000, a=a@entry=524288) at
> src/sys/kern/vfs_subr.c:1526
> #17 dounmount (mp=mp@entry=0xffff859a2e81d000, flags=524288,
> l=l@entry=0xffff859a6a698400) at src/sys/kern/vfs_mount.c:980
> #18 sys_unmount (l=0xffff859a6a698400, uap=0xffff94070afdc000,
> retval=<optimized out>) at src/sys/kern/vfs_syscalls.c:728
> #19 sy_call (sy=0xffffffff8210a050 <sysent+528>, l=0xffff859a6a698400,
> uap=0xffff94070afdc000, rval=0xffff94070afdbfb0) at
> src/sys/sys/syscallvar.h:65
> #20 sy_invoke (sy=0xffffffff8210a050 <sysent+528>, l=0xffff859a6a698400,
> uap=0xffff94070afdc000, rval=0xffff94070afdbfb0, code=22) at
> src/sys/sys/syscallvar.h:94
> #21 syscall (frame=0xffff94070afdc000) at src/sys/arch/x86/x86/syscall.c:137
> #22 handle_syscall ()
>
> where *list is (list_t *) 0xffff940059153040:
>
> {
> list_size = 240,
> list_offset = 200,
> list_head = {
> list_next = 0xffff859a07007ab8,
> list_prev = 0xffff8599c322bea8
> }
> }
>
> --
> J. Hannken-Illjes - [email protected]
b.diff
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