mirror_zfs/include
George Wilson 460d887c43
panic loop when removing slog device
There is a window in the slog removal code where a panic loop could
ensue if the system crashes during that operation. The original design
of slog removal did not persisted any state because the removal happened
synchronously. This was changed by a later commit which persisted the
vdev_removing flag and exposed this bug. If a slog removal is in
progress and happens to crash after persisting the vdev_removing flag to
the label but before the vdev is removed from the spa config, then the
pool will continue to panic on import. Here's a sample of the panic:

[  134.387411] VERIFY0(0 == dmu_buf_hold_array(os, object, offset, size,
FALSE, FTAG, &numbufs, &dbp)) failed (0 == 22)
[  134.393865] PANIC at dmu.c:1135:dmu_write()
[  134.396035] Kernel panic - not syncing: VERIFY0(0 ==
dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG, &numbufs,
&dbp)) failed (0 == 22)
[  134.397857] CPU: 2 PID: 5914 Comm: txg_sync Kdump: loaded Tainted:
P           OE     5.4.0-1100-dx2023020205-b3751f8c2-azure #106
[  134.407938] Hardware name: Microsoft Corporation Virtual
Machine/Virtual Machine, BIOS 090008  12/07/2018
[  134.407938] Call Trace:
[  134.407938]  dump_stack+0x57/0x6d
[  134.407938]  panic+0xfb/0x2d7
[  134.407938]  spl_panic+0xcf/0x102 [spl]
[  134.407938]  ? traverse_impl+0x1ca/0x420 [zfs]
[  134.407938]  ? dmu_object_alloc_impl+0x3b4/0x3c0 [zfs]
[  134.407938]  ? dnode_hold+0x1b/0x20 [zfs]
[  134.407938]  dmu_write+0xc3/0xd0 [zfs]
[  134.407938]  ? space_map_alloc+0x55/0x80 [zfs]
[  134.407938]  metaslab_sync+0x61a/0x830 [zfs]
[  134.407938]  ? queued_spin_unlock+0x9/0x10 [zfs]
[  134.407938]  vdev_sync+0x72/0x190 [zfs]
[  134.407938]  spa_sync_iterate_to_convergence+0x160/0x250 [zfs]
[  134.407938]  spa_sync+0x2f7/0x670 [zfs]
[  134.407938]  txg_sync_thread+0x22d/0x2d0 [zfs]
[  134.407938]  ? txg_dispatch_callbacks+0xf0/0xf0 [zfs]
[  134.407938]  thread_generic_wrapper+0x83/0xa0 [spl]
[  134.407938]  kthread+0x104/0x140
[  134.407938]  ? kasan_check_write.constprop.0+0x10/0x10 [spl]
[  134.407938]  ? kthread_park+0x90/0x90
[  134.457802]  ret_from_fork+0x1f/0x40

This change no longer persists the vdev_removing flag when removing slog
devices and also cleans up some code that was added which is not used.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Mark Maybee <mark.maybee@delphix.com>
Signed-off-by: George Wilson <gwilson@delphix.com>
Closes #14652
2023-03-24 10:27:07 -07:00
..
os spl: cmn_err_once() should be usable in brace-less if else statements 2023-03-15 11:13:25 -07:00
sys panic loop when removing slog device 2023-03-24 10:27:07 -07:00
.gitignore OpenZFS restructuring - move platform specific sources 2019-09-06 11:26:26 -07:00
cityhash.h libzfs: convert to -fvisibility=hidden 2021-06-03 13:17:55 -07:00
libnvpair.h nvpair: Constify string functions 2023-03-14 15:25:50 -07:00
libuutil_common.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
libuutil_impl.h libuutil: deobfuscate internal pointers 2022-11-03 09:57:05 -07:00
libuutil.h Cleanup: Remove unused uu_pname code 2022-09-19 17:33:52 -07:00
libzfs_core.h Implement a new type of zfs receive: corrective receive (-c) 2022-07-28 15:52:46 -07:00
libzfs.h nvpair: Constify string functions 2023-03-14 15:25:50 -07:00
libzfsbootenv.h lib{efi,avl,share,tpool,zfs_core,zfsbootenv,zutil}: -fvisibility=hidden 2021-06-09 17:04:32 -07:00
libzutil.h Add more ANSI colors to libzfs 2023-03-24 10:21:19 -07:00
Makefile.am Implementation of block cloning for ZFS 2023-03-10 11:59:53 -08:00
thread_pool.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfeature_common.h Implementation of block cloning for ZFS 2023-03-10 11:59:53 -08:00
zfs_comutil.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_deleg.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_fletcher.h zcommon: Refactor FPU state handling in fletcher4 2023-03-14 09:45:28 -07:00
zfs_namecheck.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00
zfs_prop.h Replace dead opensolaris.org license link 2022-07-11 14:16:13 -07:00