Re: New LOR in zfs?

On Mon, Nov 23, 2015 at 2:12 PM, Mark Johnston <markj_at_freebsd.org> wrote:
> On Mon, Nov 23, 2015 at 12:39 PM, Kurt Lidl <lidl_at_pix.net> wrote:
>> I installed a build of r291086 on a machine today
>> (previously, the machine had been running 10/stable).
>>
>> I ran the following two commands just after rebooting
>> with the new user-land bits:
>>
>> root_at_ton-95: df
>> Filesystem       1K-blocks    Used    Avail Capacity  Mounted on
>> sys/ROOT/default  18061924  804940 17256984     4%    /
>> devfs                    1       1        0   100%    /dev
>> tmpfs                65536       8    65528     0%    /tmp
>> sys/home          17257108     124 17256984     0%    /home
>> sys/local         17283924   26940 17256984     0%    /usr/local
>> sys/obj.4         19440624 2183640 17256984    11%    /usr/obj
>> sys/obj.1         19440440 2183456 17256984    11%    /usr/obj.1
>> sys/obj.2         19588696 2331712 17256984    12%    /usr/obj.2
>> sys/obj.3         19588636 2331652 17256984    12%    /usr/obj.3
>> sys/ports         17257080      96 17256984     0%    /usr/ports
>> sys/src           19740468 2483484 17256984    13%    /usr/src
>> sys/var           17358024  101040 17256984     1%    /var
>> root_at_ton-96: zfs set mountpoint=/usr/obj.4 sys/obj.4
>>
>> I got a LOR (new to me, at any rate) on the console:
>> lock order reversal:
>>  1st 0xfffff8000612da38 zfs (zfs) _at_ /usr/src/sys/kern/vfs_mount.c:1224
>>  2nd 0xfffff8000612d4b0 zfs_gfs (zfs_gfs) _at_
>> /usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/gfs.c:494
>> stack backtrace:
>> #0 0xc05b1e3c at __lockmgr_args???=?-~????+0xa3c
>> #1 0xc06a9118 at vop_std???=?-~????lock+0x38
>> #2 0xc09e8164 at VOP_???=?-~????LOCK1_APV+0x104
>> #3 0xc06d125c a???=?-~????t _vn_lock+0x9c
>> #4 0xc12a7b04 a???=?-~????t gfs_file_create+0x64
>> #5 0xc12???=?-~????a7c14 at gfs_dir_create+0x14
>> #6???=?-~???? 0xc139fc14 at zfsctl_mknode_sn???=?-~????apdir+0x54
>> #7 0xc12a82bc at gfs???=?-~????_dir_lookup+0x31c
>> #8 0xc139f6cc???=?-~???? at zfsctl_root_lookup+0x12c
>> #9???=?-~???? 0xc139f7b4 at zfsctl_umount_sn???=?-~????apshots+0x54
>> #10 0xc13bb44c at ???=?-~????zfs_umount+0x4c
>> #11 0xc06b34a8 ???=?-~????at dounmount+0xbc8
>> #12 0xc06b38???=?-~????f0 at sys_unmount+0x410
>> #13 0xc???=?-~????09de004 at syscall+0x3c4
>>
>> The machine in question is a sparc4u machine, but I do not think
>> it matters.
>
> The garbled output should be fixed by r291217.

This is a tough one, but Will (CC'ed) has made some progress fixing it.

-Alan