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commit 613b14884b8595e20b9fac4126bf627313827fbe upstream.
This can't happen right now, but in preparation for allowing
bio_split_to_limits() returning NULL if it ended the bio, check for it
in all the callers.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5e8daf906f890560df430d30617c692a794acb73 ]
A race condition still exists when removing and re-creating md devices
in test cases. However, it is only seen on some setups.
The race condition was tracked down to a reference still being held
to the kobject by the rdev in the md_rdev_misc_wq which will be released
in rdev_delayed_delete().
md_alloc() waits for previous deletions by waiting on the md_misc_wq,
but the md_rdev_misc_wq may still be holding a reference to a recently
removed device.
To fix this, also flush the md_rdev_misc_wq in md_alloc().
Signed-off-by: David Sloan <david.sloan@eideticom.com>
[logang@deltatee.com: rewrote commit message]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0dd84b319352bb8ba64752d4e45396d8b13e6018 upstream.
From the link [1], we can see raid1d was running even after the path
raid_dtr -> md_stop -> __md_stop.
Let's stop write first in destructor to align with normal md-raid to
fix the KASAN issue.
[1]. https://lore.kernel.org/linux-raid/CAPhsuW5gc4AakdGNdF8ubpezAuDLFOYUO_sfMZcec6hQFm8nhg@mail.gmail.com/T/#m7f12bf90481c02c6d2da68c64aeed4779b7df74a
Fixes: 48df498daf62 ("md: move bitmap_destroy to the beginning of __md_stop")
Reported-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1d258758cf06a0734482989911d184dd5837ed4e upstream.
This reverts commit e151db8ecfb019b7da31d076130a794574c89f6f. Because it
obviously breaks clustered raid as noticed by Neil though it fixed KASAN
issue for dm-raid, let's revert it and fix KASAN issue in next commit.
[1]. https://lore.kernel.org/linux-raid/a6657e08-b6a7-358b-2d2a-0ac37d49d23a@linux.dev/T/#m95ac225cab7409f66c295772483d091084a6d470
Fixes: e151db8ecfb0 ("md-raid: destroy the bitmap after destroying the thread")
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9973f0fa7d20269fe6fefe6333997fb5914449c1 ]
The mdadm test 07layouts randomly produces a kernel hung task deadlock.
The deadlock is caused by the suspend_lo/suspend_hi files being set by
the mdadm background process during reshape and not being cleared
because the process hangs. (Leaving aside the issue of the fragility of
freezing kernel tasks by buggy userspace processes...)
When the background mdadm process hangs it, is waiting (without a
timeout) on a change to the sync_completed file signalling that the
reshape has completed. The process is woken up a couple times when
the reshape finishes but it is woken up before MD_RECOVERY_RUNNING
is cleared so sync_completed_show() reports 0 instead of "none".
To fix this, notify the sysfs file in md_reap_sync_thread() after
MD_RECOVERY_RUNNING has been cleared. This wakes up mdadm and causes
it to continue and write to suspend_lo/suspend_hi to allow IO to
continue.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit e151db8ecfb019b7da31d076130a794574c89f6f upstream.
When we ran the lvm test "shell/integrity-blocksize-3.sh" on a kernel with
kasan, we got failure in write_page.
The reason for the failure is that md_bitmap_destroy is called before
destroying the thread and the thread may be waiting in the function
write_page for the bio to complete. When the thread finishes waiting, it
executes "if (test_bit(BITMAP_WRITE_ERROR, &bitmap->flags))", which
triggers the kasan warning.
Note that the commit 48df498daf62 that caused this bug claims that it is
neede for md-cluster, you should check md-cluster and possibly find
another bugfix for it.
BUG: KASAN: use-after-free in write_page+0x18d/0x680 [md_mod]
Read of size 8 at addr ffff889162030c78 by task mdX_raid1/5539
CPU: 10 PID: 5539 Comm: mdX_raid1 Not tainted 5.19.0-rc2 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
print_report.cold+0x45/0x57a
? __lock_text_start+0x18/0x18
? write_page+0x18d/0x680 [md_mod]
kasan_report+0xa8/0xe0
? write_page+0x18d/0x680 [md_mod]
kasan_check_range+0x13f/0x180
write_page+0x18d/0x680 [md_mod]
? super_sync+0x4d5/0x560 [dm_raid]
? md_bitmap_file_kick+0xa0/0xa0 [md_mod]
? rs_set_dev_and_array_sectors+0x2e0/0x2e0 [dm_raid]
? mutex_trylock+0x120/0x120
? preempt_count_add+0x6b/0xc0
? preempt_count_sub+0xf/0xc0
md_update_sb+0x707/0xe40 [md_mod]
md_reap_sync_thread+0x1b2/0x4a0 [md_mod]
md_check_recovery+0x533/0x960 [md_mod]
raid1d+0xc8/0x2a20 [raid1]
? var_wake_function+0xe0/0xe0
? psi_group_change+0x411/0x500
? preempt_count_sub+0xf/0xc0
? _raw_spin_lock_irqsave+0x78/0xc0
? __lock_text_start+0x18/0x18
? raid1_end_read_request+0x2a0/0x2a0 [raid1]
? preempt_count_sub+0xf/0xc0
? _raw_spin_unlock_irqrestore+0x19/0x40
? del_timer_sync+0xa9/0x100
? try_to_del_timer_sync+0xc0/0xc0
? _raw_spin_lock_irqsave+0x78/0xc0
? __lock_text_start+0x18/0x18
? __list_del_entry_valid+0x68/0xa0
? finish_wait+0xa3/0x100
md_thread+0x161/0x260 [md_mod]
? unregister_md_personality+0xa0/0xa0 [md_mod]
? _raw_spin_lock_irqsave+0x78/0xc0
? prepare_to_wait_event+0x2c0/0x2c0
? unregister_md_personality+0xa0/0xa0 [md_mod]
kthread+0x148/0x180
? kthread_complete_and_exit+0x20/0x20
ret_from_fork+0x1f/0x30
</TASK>
Allocated by task 5522:
kasan_save_stack+0x1e/0x40
__kasan_kmalloc+0x80/0xa0
md_bitmap_create+0xa8/0xe80 [md_mod]
md_run+0x777/0x1300 [md_mod]
raid_ctr+0x249c/0x4a30 [dm_raid]
dm_table_add_target+0x2b0/0x620 [dm_mod]
table_load+0x1c8/0x400 [dm_mod]
ctl_ioctl+0x29e/0x560 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x20 [dm_mod]
__do_compat_sys_ioctl+0xfa/0x160
do_syscall_64+0x90/0xc0
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Freed by task 5680:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x40
kasan_set_free_info+0x20/0x40
__kasan_slab_free+0xf7/0x140
kfree+0x80/0x240
md_bitmap_free+0x1c3/0x280 [md_mod]
__md_stop+0x21/0x120 [md_mod]
md_stop+0x9/0x40 [md_mod]
raid_dtr+0x1b/0x40 [dm_raid]
dm_table_destroy+0x98/0x1e0 [dm_mod]
__dm_destroy+0x199/0x360 [dm_mod]
dev_remove+0x10c/0x160 [dm_mod]
ctl_ioctl+0x29e/0x560 [dm_mod]
dm_compat_ctl_ioctl+0x7/0x20 [dm_mod]
__do_compat_sys_ioctl+0xfa/0x160
do_syscall_64+0x90/0xc0
entry_SYSCALL_64_after_hwframe+0x46/0xb0
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 48df498daf62 ("md: move bitmap_destroy to the beginning of __md_stop")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1e267742283a4b5a8ca65755c44166be27e9aa0f ]
Generally, the md_unregister_thread is called with reconfig_mutex, but
raid_message in dm-raid doesn't hold reconfig_mutex to unregister thread,
so md_unregister_thread can be called simulitaneously from two call sites
in theory.
Then after previous commit which remove the protection of reconfig_mutex
for md_unregister_thread completely, the potential issue could be worse
than before.
Let's take pers_lock at the beginning of function to ensure reentrancy.
Reported-by: Donald Buczek <buczek@molgen.mpg.de>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 42b805af102471f53e3c7867b8c2b502ea4eef7e upstream.
Now io_acct_set is alloc and free in personality. Remove the codes that
free io_acct_set in md_free and md_stop.
Fixes: 0c031fd37f69 (md: Move alloc/free acct bioset in to personality)
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64c54d9244a4efe9bc6e9c98e13c4bbb8bb39083 upstream.
The bug is here:
if (!rdev || rdev->desc_nr != nr) {
The list iterator value 'rdev' will *always* be set and non-NULL
by rdev_for_each_rcu(), so it is incorrect to assume that the
iterator value will be NULL if the list is empty or no element
found (In fact, it will be a bogus pointer to an invalid struct
object containing the HEAD). Otherwise it will bypass the check
and lead to invalid memory access passing the check.
To fix the bug, use a new variable 'iter' as the list iterator,
while using the original variable 'pdev' as a dedicated pointer to
point to the found element.
Cc: stable@vger.kernel.org
Fixes: 70bcecdb1534 ("md-cluster: Improve md_reload_sb to be less error prone")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fc8738343eefc4ea8afb6122826dea48eacde514 upstream.
The bug is here:
if (!rdev)
The list iterator value 'rdev' will *always* be set and non-NULL
by rdev_for_each(), so it is incorrect to assume that the iterator
value will be NULL if the list is empty or no element found.
Otherwise it will bypass the NULL check and lead to invalid memory
access passing the check.
To fix the bug, use a new variable 'iter' as the list iterator,
while using the original variable 'rdev' as a dedicated pointer to
point to the found element.
Cc: stable@vger.kernel.org
Fixes: 2aa82191ac36 ("md-cluster: Perform a lazy update")
Acked-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Acked-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b81e0c2372e65e5627864ba034433b64b2fc73f5 upstream.
Drop various include not actually used in genhd.h itself, and
move the remaning includes closer together.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reported-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>a
Reported-by: "H. Nikolaus Schaller" <hns@goldelico.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: "Maciej W. Rozycki" <macro@orcam.me.uk>
[ resolves MIPS build failure by luck, root cause needs to be fixed in
Linus's tree properly, but this is needed for now to fix the build - gregkh ]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 55df1ce0d4e086e05a8ab20619c73c729350f965 upstream.
The superblock of version 1.0 doesn't get moved to the new position on a
device size change. This leads to a rdev without a superblock on a known
position, the raid can't be re-assembled.
The line was removed by mistake and is re-added by this patch.
Fixes: d9c0fa509eaf ("md: fix max sectors calculation for super 1.0")
Cc: stable@vger.kernel.org
Signed-off-by: Markus Hochholdinger <markus@hochholdinger.net>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8b9e2291e355a0eafdd5b1e21a94a6659f24b351 ]
When the in memory flag is changed, we need to persist the change in the
rdev superblock flags. This is needed for "writemostly" and "failfast".
Reviewed-by: Li Feng <fengli@smartx.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Commit b0140891a8cea3 ("md: Fix race when creating a new md device.")
not only moved assigning mddev->gendisk before calling add_disk, which
fixes the races described in the commit log, but also added a
mddev->open_mutex critical section over add_disk and creation of the
md kobj. Adding a kobject after add_disk is racy vs deleting the gendisk
right after adding it, but md already prevents against that by holding
a mddev->active reference.
On the other hand taking this lock added a lock order reversal with what
is not disk->open_mutex (used to be bdev->bd_mutex when the commit was
added) for partition devices, which need that lock for the internal open
for the partition scan, and a recent commit also takes it for
non-partitioned devices, leading to further lockdep splatter.
Fixes: b0140891a8ce ("md: Fix race when creating a new md device.")
Fixes: d62633873590 ("block: support delayed holder registration")
Reported-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: syzbot+fadc0aaf497e6a493b9f@syzkaller.appspotmail.com
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
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Merge tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
"Pretty calm round, mostly just NVMe and a bit of MD:
- NVMe updates (via Christoph)
- improve the APST configuration algorithm (Alexey Bogoslavsky)
- look for StorageD3Enable on companion ACPI device
(Mario Limonciello)
- allow selecting the network interface for TCP connections
(Martin Belanger)
- misc cleanups (Amit Engel, Chaitanya Kulkarni, Colin Ian King,
Christoph)
- move the ACPI StorageD3 code to drivers/acpi/ and add quirks
for certain AMD CPUs (Mario Limonciello)
- zoned device support for nvmet (Chaitanya Kulkarni)
- fix the rules for changing the serial number in nvmet
(Noam Gottlieb)
- various small fixes and cleanups (Dan Carpenter, JK Kim,
Chaitanya Kulkarni, Hannes Reinecke, Wesley Sheng, Geert
Uytterhoeven, Daniel Wagner)
- MD updates (Via Song)
- iostats rewrite (Guoqing Jiang)
- raid5 lock contention optimization (Gal Ofri)
- Fall through warning fix (Gustavo)
- Misc fixes (Gustavo, Jiapeng)"
* tag 'for-5.14/drivers-2021-06-29' of git://git.kernel.dk/linux-block: (78 commits)
nvmet: use NVMET_MAX_NAMESPACES to set nn value
loop: Fix missing discard support when using LOOP_CONFIGURE
nvme.h: add missing nvme_lba_range_type endianness annotations
nvme: remove zeroout memset call for struct
nvme-pci: remove zeroout memset call for struct
nvmet: remove zeroout memset call for struct
nvmet: add ZBD over ZNS backend support
nvmet: add Command Set Identifier support
nvmet: add nvmet_req_bio put helper for backends
nvmet: add req cns error complete helper
block: export blk_next_bio()
nvmet: remove local variable
nvmet: use nvme status value directly
nvmet: use u32 type for the local variable nsid
nvmet: use u32 for nvmet_subsys max_nsid
nvmet: use req->cmd directly in file-ns fast path
nvmet: use req->cmd directly in bdev-ns fast path
nvmet: make ver stable once connection established
nvmet: allow mn change if subsys not discovered
nvmet: make sn stable once connection was established
...
Given it is not obvious for the error handling, let's try to add some
comments here to make it clear.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The bio_set (io_acct_set) is used by personalities to clone bio and
trace the timestamp of bio. Some personalities such as raid1/10 don't
need the bio_set, so add check to not create it unconditionally.
Also update the comment for md_account_bio to make it more clear.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The attribute_group structs are never modified, they're only passed to
sysfs_create_group() and sysfs_remove_group(). Make them const to allow
the compiler to put them in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Song Liu <song@kernel.org>
We introduce a new bioset (io_acct_set) for raid0 and raid5 since they
don't own clone infrastructure to accounting io. And the bioset is added
to mddev instead of to raid0 and raid5 layer, because with this way, we
can put common functions to md.h and reuse them in raid0 and raid5.
Also struct md_io_acct is added accordingly which includes io start_time,
the origin bio and cloned bio. Then we can call bio_{start,end}_io_acct
to get related io status.
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
The commit 41d2d848e5c0 ("md: improve io stats accounting") could cause
double fault problem per the report [1], and also it is not correct to
change ->bi_end_io if md don't own it, so let's revert it.
And io stats accounting will be replemented in later commits.
[1]. https://lore.kernel.org/linux-raid/3bf04253-3fad-434a-63a7-20214e38cf26@gmail.com/T/#t
Fixes: 41d2d848e5c0 ("md: improve io stats accounting")
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
Convert the md driver to use the blk_alloc_disk and blk_cleanup_disk
helpers to simplify gendisk and request_queue allocation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20210521055116.1053587-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Instead of returning an existing mddev, just for it to be discarded
later directly return -EEXIST. Rename the function to mddev_alloc now
that it doesn't find an existing mddev.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Allocate the new mddev first speculatively, which greatly simplifies
the code flow.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Split out a self contained helper to find a free minor for the md
"unit" number.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Split mddev_find into a simple mddev_find that just finds an existing
mddev by the unit number, and a more complicated mddev_find that deals
with find or allocating a mddev.
This turns out to fix this bug reported by Zhao Heming.
----------------------------- snip ------------------------------
commit d3374825ce57 ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.
*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt
*** script ***
about trigger 1 time with 10 tests
`1 node1="15sp3-mdcluster1"
2 node2="15sp3-mdcluster2"
3
4 mdadm -Ss
5 ssh ${node2} "mdadm -Ss"
6 wipefs -a /dev/sda /dev/sdb
7 mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
/dev/sdb --assume-clean
8
9 for i in {1..100}; do
10 echo ==== $i ====;
11
12 echo "test ...."
13 ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
14 sleep 1
15
16 echo "clean ....."
17 ssh ${node2} "mdadm -Ss"
18 done
`
I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.
*** stack ***
`ID: 2831 TASK: ffff8dd7223b5040 CPU: 0 COMMAND: "mdadm"
#0 [ffffa15d00a13b90] __schedule at ffffffffb8f1935f
#1 [ffffa15d00a13ba8] exact_lock at ffffffffb8a4a66d
#2 [ffffa15d00a13bb0] kobj_lookup at ffffffffb8c62fe3
#3 [ffffa15d00a13c28] __blkdev_get at ffffffffb89273b9
#4 [ffffa15d00a13c98] blkdev_get at ffffffffb8927964
#5 [ffffa15d00a13cb0] do_dentry_open at ffffffffb88dc4b4
#6 [ffffa15d00a13ce0] path_openat at ffffffffb88f0ccc
#7 [ffffa15d00a13db8] do_filp_open at ffffffffb88f32bb
#8 [ffffa15d00a13ee0] do_sys_open at ffffffffb88ddc7d
#9 [ffffa15d00a13f38] do_syscall_64 at ffffffffb86053cb ffffffffb900008c
or:
[ 884.226509] mddev_put+0x1c/0xe0 [md_mod]
[ 884.226515] md_open+0x3c/0xe0 [md_mod]
[ 884.226518] __blkdev_get+0x30d/0x710
[ 884.226520] ? bd_acquire+0xd0/0xd0
[ 884.226522] blkdev_get+0x14/0x30
[ 884.226524] do_dentry_open+0x204/0x3a0
[ 884.226531] path_openat+0x2fc/0x1520
[ 884.226534] ? seq_printf+0x4e/0x70
[ 884.226536] do_filp_open+0x9b/0x110
[ 884.226542] ? md_release+0x20/0x20 [md_mod]
[ 884.226543] ? seq_read+0x1d8/0x3e0
[ 884.226545] ? kmem_cache_alloc+0x18a/0x270
[ 884.226547] ? do_sys_open+0x1bd/0x260
[ 884.226548] do_sys_open+0x1bd/0x260
[ 884.226551] do_syscall_64+0x5b/0x1e0
[ 884.226554] entry_SYSCALL_64_after_hwframe+0x44/0xa9
`
*** rootcause ***
"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.
The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.
`<thread 1>: "mdadm -Ss"
md_release
mddev_put deletes mddev from all_mddevs
queue_work for mddev_delayed_delete
at this time, "/dev/md0" is still available for opening
<thread 2>: "mdadm --monitor ..."
md_open
+ mddev_find can't find mddev of /dev/md0, and create a new mddev and
| return.
+ trigger "if (mddev->gendisk != bdev->bd_disk)" and return
-ERESTARTSYS.
`
In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.
In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.
------------------------------ snip ------------------------------
Cc: stable@vger.kernel.org
Fixes: d3374825ce57 ("md: make devices disappear when they are no longer needed.")
Reported-by: Heming Zhao <heming.zhao@suse.com>
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
Factor out a self-contained helper to just lookup a mddev by the dev_t
"unit".
Cc: stable@vger.kernel.org
Reviewed-by: Heming Zhao <heming.zhao@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>
commit d3374825ce57 ("md: make devices disappear when they are no longer
needed.") introduced protection between mddev creating & removing. The
md_open shouldn't create mddev when all_mddevs list doesn't contain
mddev. With currently code logic, there will be very easy to trigger
soft lockup in non-preempt env.
This patch changes md_open returning from -ERESTARTSYS to -EBUSY, which
will break the infinitely retry when md_open enter racing area.
This patch is partly fix soft lockup issue, full fix needs mddev_find
is split into two functions: mddev_find & mddev_find_or_alloc. And
md_open should call new mddev_find (it only does searching job).
For more detail, please refer with Christoph's "split mddev_find" patch
in later commits.
*** env ***
kvm-qemu VM 2C1G with 2 iscsi luns
kernel should be non-preempt
*** script ***
about trigger every time with below script
```
1 node1="mdcluster1"
2 node2="mdcluster2"
3
4 mdadm -Ss
5 ssh ${node2} "mdadm -Ss"
6 wipefs -a /dev/sda /dev/sdb
7 mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda \
/dev/sdb --assume-clean
8
9 for i in {1..10}; do
10 echo ==== $i ====;
11
12 echo "test ...."
13 ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb"
14 sleep 1
15
16 echo "clean ....."
17 ssh ${node2} "mdadm -Ss"
18 done
```
I use mdcluster env to trigger soft lockup, but it isn't mdcluster
speical bug. To stop md array in mdcluster env will do more jobs than
non-cluster array, which will leave enough time/gap to allow kernel to
run md_open.
*** stack ***
```
[ 884.226509] mddev_put+0x1c/0xe0 [md_mod]
[ 884.226515] md_open+0x3c/0xe0 [md_mod]
[ 884.226518] __blkdev_get+0x30d/0x710
[ 884.226520] ? bd_acquire+0xd0/0xd0
[ 884.226522] blkdev_get+0x14/0x30
[ 884.226524] do_dentry_open+0x204/0x3a0
[ 884.226531] path_openat+0x2fc/0x1520
[ 884.226534] ? seq_printf+0x4e/0x70
[ 884.226536] do_filp_open+0x9b/0x110
[ 884.226542] ? md_release+0x20/0x20 [md_mod]
[ 884.226543] ? seq_read+0x1d8/0x3e0
[ 884.226545] ? kmem_cache_alloc+0x18a/0x270
[ 884.226547] ? do_sys_open+0x1bd/0x260
[ 884.226548] do_sys_open+0x1bd/0x260
[ 884.226551] do_syscall_64+0x5b/0x1e0
[ 884.226554] entry_SYSCALL_64_after_hwframe+0x44/0xa9
```
*** rootcause ***
"mdadm -A" (or other array assemble commands) will start a daemon "mdadm
--monitor" by default. When "mdadm -Ss" is running, the stop action will
wakeup "mdadm --monitor". The "--monitor" daemon will immediately get
info from /proc/mdstat. This time mddev in kernel still exist, so
/proc/mdstat still show md device, which makes "mdadm --monitor" to open
/dev/md0.
The previously "mdadm -Ss" is removing action, the "mdadm --monitor"
open action will trigger md_open which is creating action. Racing is
happening.
```
<thread 1>: "mdadm -Ss"
md_release
mddev_put deletes mddev from all_mddevs
queue_work for mddev_delayed_delete
at this time, "/dev/md0" is still available for opening
<thread 2>: "mdadm --monitor ..."
md_open
+ mddev_find can't find mddev of /dev/md0, and create a new mddev and
| return.
+ trigger "if (mddev->gendisk != bdev->bd_disk)" and return
-ERESTARTSYS.
```
In non-preempt kernel, <thread 2> is occupying on current CPU. and
mddev_delayed_delete which was created in <thread 1> also can't be
schedule.
In preempt kernel, it can also trigger above racing. But kernel doesn't
allow one thread running on a CPU all the time. after <thread 2> running
some time, the later "mdadm -A" (refer above script line 13) will call
md_alloc to alloc a new gendisk for mddev. it will break md_open
statement "if (mddev->gendisk != bdev->bd_disk)" and return 0 to caller,
the soft lockup is broken.
Cc: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
Reading /proc/mdstat with a read buffer size that would not
fit the unused status line in the first read will skip this
line from the output.
So 'dd if=/proc/mdstat bs=64 2>/dev/null' will not print something
like: unused devices: <none>
Don't return NULL immediately in start() for v=2 but call
show() once to print the status line also for multiple reads.
Cc: stable@vger.kernel.org
Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface")
Signed-off-by: Jan Glauber <jglauber@digitalocean.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Move these logic from raid0.c to md.c, so that we can also use it in
raid10.c.
Reviewed-by: Coly Li <colyli@suse.de>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Tested-by: Adrian Huang <ahuang12@lenovo.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Make the read-only check in restart_array identical to the other two
read-only checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
->meta_bdev is optional and not set for most arrays. Add a
rdev_read_only helper that calls bdev_read_only for both devices
in a safe way.
Fixes: 6f0d9689b670 ("block: remove the NULL bdev check in bdev_read_only")
Reported-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
md_bio_alloc_sync is never called with a NULL mddev, and ->sync_set is
initialized in md_run, so it always must be initialized as well. Just
open code the remaining call to bio_alloc_bioset.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use an on-stack bio and biovec for the single page synchronous I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bio_alloc_mddev is never called with a NULL mddev, and ->bio_set is
initialized in md_run, so it always must be initialized as well. Just
open code the remaining call to bio_alloc_bioset.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rework the I/O accounting for bio based drivers to use ->bi_bdev. This
means all drivers can now simply use bio_start_io_acct to start
accounting, and it will take partitions into account automatically. To
end I/O account either bio_end_io_acct can be used if the driver never
remaps I/O to a different device, or bio_end_io_acct_remapped if the
driver did remap the I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device. From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
One customer reports a crash problem which causes by flush request. It
triggers a warning before crash.
/* new request after previous flush is completed */
if (ktime_after(req_start, mddev->prev_flush_start)) {
WARN_ON(mddev->flush_bio);
mddev->flush_bio = bio;
bio = NULL;
}
The WARN_ON is triggered. We use spin lock to protect prev_flush_start and
flush_bio in md_flush_request. But there is no lock protection in
md_submit_flush_data. It can set flush_bio to NULL first because of
compiler reordering write instructions.
For example, flush bio1 sets flush bio to NULL first in
md_submit_flush_data. An interrupt or vmware causing an extended stall
happen between updating flush_bio and prev_flush_start. Because flush_bio
is NULL, flush bio2 can get the lock and submit to underlayer disks. Then
flush bio1 updates prev_flush_start after the interrupt or extended stall.
Then flush bio3 enters in md_flush_request. The start time req_start is
behind prev_flush_start. The flush_bio is not NULL(flush bio2 hasn't
finished). So it can trigger the WARN_ON now. Then it calls INIT_WORK
again. INIT_WORK() will re-initialize the list pointers in the
work_struct, which then can result in a corrupted work list and the
work_struct queued a second time. With the work list corrupted, it can
lead in invalid work items being used and cause a crash in
process_one_work.
We need to make sure only one flush bio can be handled at one same time.
So add spin lock in md_submit_flush_data to protect prev_flush_start and
flush_bio in an atomic way.
Reviewed-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
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Merge tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
"Nothing major in here:
- NVMe pull request from Christoph:
- nvmet passthrough improvements (Chaitanya Kulkarni)
- fcloop error injection support (James Smart)
- read-only support for zoned namespaces without Zone Append
(Javier González)
- improve some error message (Minwoo Im)
- reject I/O to offline fabrics namespaces (Victor Gladkov)
- PCI queue allocation cleanups (Niklas Schnelle)
- remove an unused allocation in nvmet (Amit Engel)
- a Kconfig spelling fix (Colin Ian King)
- nvme_req_qid simplication (Baolin Wang)
- MD pull request from Song:
- Fix race condition in md_ioctl() (Dae R. Jeong)
- Initialize read_slot properly for raid10 (Kevin Vigor)
- Code cleanup (Pankaj Gupta)
- md-cluster resync/reshape fix (Zhao Heming)
- Move null_blk into its own directory (Damien Le Moal)
- null_blk zone and discard improvements (Damien Le Moal)
- bcache race fix (Dongsheng Yang)
- Set of rnbd fixes/improvements (Gioh Kim, Guoqing Jiang, Jack Wang,
Lutz Pogrell, Md Haris Iqbal)
- lightnvm NULL pointer deref fix (tangzhenhao)
- sr in_interrupt() removal (Sebastian Andrzej Siewior)
- FC endpoint security support for s390/dasd (Jan Höppner, Sebastian
Ott, Vineeth Vijayan). From the s390 arch guys, arch bits included
as it made it easier for them to funnel the feature through the
block driver tree.
- Follow up fixes (Colin Ian King)"
* tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block: (64 commits)
block: drop dead assignments in loop_init()
sr: Remove in_interrupt() usage in sr_init_command().
sr: Switch the sector size back to 2048 if sr_read_sector() changed it.
cdrom: Reset sector_size back it is not 2048.
drivers/lightnvm: fix a null-ptr-deref bug in pblk-core.c
null_blk: Move driver into its own directory
null_blk: Allow controlling max_hw_sectors limit
null_blk: discard zones on reset
null_blk: cleanup discard handling
null_blk: Improve implicit zone close
null_blk: improve zone locking
block: Align max_hw_sectors to logical blocksize
null_blk: Fail zone append to conventional zones
null_blk: Fix zone size initialization
bcache: fix race between setting bdev state to none and new write request direct to backing
block/rnbd: fix a null pointer dereference on dev->blk_symlink_name
block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
block/rnbd: call kobject_put in the failure path
Documentation/ABI/rnbd-srv: add document for force_close
block/rnbd-srv: close a mapped device from server side.
...
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Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
"Another series of killing more code than what is being added, again
thanks to Christoph's relentless cleanups and tech debt tackling.
This contains:
- blk-iocost improvements (Baolin Wang)
- part0 iostat fix (Jeffle Xu)
- Disable iopoll for split bios (Jeffle Xu)
- block tracepoint cleanups (Christoph Hellwig)
- Merging of struct block_device and hd_struct (Christoph Hellwig)
- Rework/cleanup of how block device sizes are updated (Christoph
Hellwig)
- Simplification of gendisk lookup and removal of block device
aliasing (Christoph Hellwig)
- Block device ioctl cleanups (Christoph Hellwig)
- Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)
- Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)
- sbitmap improvements (Pavel Begunkov)
- Hybrid polling fix (Pavel Begunkov)
- bvec iteration improvements (Pavel Begunkov)
- Zone revalidation fixes (Damien Le Moal)
- blk-throttle limit fix (Yu Kuai)
- Various little fixes"
* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
blk-mq: fix msec comment from micro to milli seconds
blk-mq: update arg in comment of blk_mq_map_queue
blk-mq: add helper allocating tagset->tags
Revert "block: Fix a lockdep complaint triggered by request queue flushing"
nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
block: disable iopoll for split bio
block: Improve blk_revalidate_disk_zones() checks
sbitmap: simplify wrap check
sbitmap: replace CAS with atomic and
sbitmap: remove swap_lock
sbitmap: optimise sbitmap_deferred_clear()
blk-mq: skip hybrid polling if iopoll doesn't spin
blk-iocost: Factor out the base vrate change into a separate function
blk-iocost: Factor out the active iocgs' state check into a separate function
blk-iocost: Move the usage ratio calculation to the correct place
blk-iocost: Remove unnecessary advance declaration
blk-iocost: Fix some typos in comments
blktrace: fix up a kerneldoc comment
block: remove the request_queue to argument request based tracepoints
...
This reverts commit 2628089b74d5a64bd0bcb5d247a18f78d7b6f4d0.
Matthew Ruffell reported data corruption in raid10 due to the changes
in discard handling [1]. Revert these changes before we find a proper fix.
[1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/
Cc: Matthew Ruffell <matthew.ruffell@canonical.com>
Cc: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
The request_queue can trivially be derived from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use struct block_device to lookup partitions on a disk. This removes
all usage of struct hd_struct from the I/O path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: Chao Yu <yuchao0@huawei.com> [f2fs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allocate hd_struct together with struct block_device to pre-load
the lifetime rule changes in preparation of merging the two structures.
Note that part0 was previously embedded into struct gendisk, but is
a separate allocation now, and already points to the block_device instead
of the hd_struct. The lifetime of struct gendisk is still controlled by
the struct device embedded in the part0 hd_struct.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a little helper to find the kobject for a struct block_device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
md-cluster uses MD_CLUSTER_SEND_LOCK to make node can exclusively send msg.
During sending msg, node can concurrently receive msg from another node.
When node does resync job, grab token_lockres:EX may trigger a deadlock:
```
nodeA nodeB
-------------------- --------------------
a.
send METADATA_UPDATED
held token_lockres:EX
b.
md_do_sync
resync_info_update
send RESYNCING
+ set MD_CLUSTER_SEND_LOCK
+ wait for holding token_lockres:EX
c.
mdadm /dev/md0 --remove /dev/sdg
+ held reconfig_mutex
+ send REMOVE
+ wait_event(MD_CLUSTER_SEND_LOCK)
d.
recv_daemon //METADATA_UPDATED from A
process_metadata_update
+ (mddev_trylock(mddev) ||
MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD)
//this time, both return false forever
```
Explaination:
a. A send METADATA_UPDATED
This will block another node to send msg
b. B does sync jobs, which will send RESYNCING at intervals.
This will be block for holding token_lockres:EX lock.
c. B do "mdadm --remove", which will send REMOVE.
This will be blocked by step <b>: MD_CLUSTER_SEND_LOCK is 1.
d. B recv METADATA_UPDATED msg, which send from A in step <a>.
This will be blocked by step <c>: holding mddev lock, it makes
wait_event can't hold mddev lock. (btw,
MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD keep ZERO in this scenario.)
There is a similar deadlock in commit 0ba959774e93
("md-cluster: use sync way to handle METADATA_UPDATED msg")
In that commit, step c is "update sb". This patch step c is
"mdadm --remove".
For fixing this issue, we can refer the solution of function:
metadata_update_start. Which does the same grab lock_token action.
lock_comm can use the same steps to avoid deadlock. By moving
MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD from lock_token to lock_comm.
It enlarge a little bit window of MD_CLUSTER_HOLDING_MUTEX_FOR_RECVD,
but it is safe & can break deadlock.
Repro steps (I only triggered 3 times with hundreds tests):
two nodes share 3 iSCSI luns: sdg/sdh/sdi. Each lun size is 1GB.
```
ssh root@node2 "mdadm -S --scan"
mdadm -S --scan
for i in {g,h,i};do dd if=/dev/zero of=/dev/sd$i oflag=direct bs=1M \
count=20; done
mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sdg /dev/sdh \
--bitmap-chunk=1M
ssh root@node2 "mdadm -A /dev/md0 /dev/sdg /dev/sdh"
sleep 5
mkfs.xfs /dev/md0
mdadm --manage --add /dev/md0 /dev/sdi
mdadm --wait /dev/md0
mdadm --grow --raid-devices=3 /dev/md0
mdadm /dev/md0 --fail /dev/sdg
mdadm /dev/md0 --remove /dev/sdg
mdadm --grow --raid-devices=2 /dev/md0
```
test script will hung when executing "mdadm --remove".
```
# dump stacks by "echo t > /proc/sysrq-trigger"
md0_cluster_rec D 0 5329 2 0x80004000
Call Trace:
__schedule+0x1f6/0x560
? _cond_resched+0x2d/0x40
? schedule+0x4a/0xb0
? process_metadata_update.isra.0+0xdb/0x140 [md_cluster]
? wait_woken+0x80/0x80
? process_recvd_msg+0x113/0x1d0 [md_cluster]
? recv_daemon+0x9e/0x120 [md_cluster]
? md_thread+0x94/0x160 [md_mod]
? wait_woken+0x80/0x80
? md_congested+0x30/0x30 [md_mod]
? kthread+0x115/0x140
? __kthread_bind_mask+0x60/0x60
? ret_from_fork+0x1f/0x40
mdadm D 0 5423 1 0x00004004
Call Trace:
__schedule+0x1f6/0x560
? __schedule+0x1fe/0x560
? schedule+0x4a/0xb0
? lock_comm.isra.0+0x7b/0xb0 [md_cluster]
? wait_woken+0x80/0x80
? remove_disk+0x4f/0x90 [md_cluster]
? hot_remove_disk+0xb1/0x1b0 [md_mod]
? md_ioctl+0x50c/0xba0 [md_mod]
? wait_woken+0x80/0x80
? blkdev_ioctl+0xa2/0x2a0
? block_ioctl+0x39/0x40
? ksys_ioctl+0x82/0xc0
? __x64_sys_ioctl+0x16/0x20
? do_syscall_64+0x5f/0x150
? entry_SYSCALL_64_after_hwframe+0x44/0xa9
md0_resync D 0 5425 2 0x80004000
Call Trace:
__schedule+0x1f6/0x560
? schedule+0x4a/0xb0
? dlm_lock_sync+0xa1/0xd0 [md_cluster]
? wait_woken+0x80/0x80
? lock_token+0x2d/0x90 [md_cluster]
? resync_info_update+0x95/0x100 [md_cluster]
? raid1_sync_request+0x7d3/0xa40 [raid1]
? md_do_sync.cold+0x737/0xc8f [md_mod]
? md_thread+0x94/0x160 [md_mod]
? md_congested+0x30/0x30 [md_mod]
? kthread+0x115/0x140
? __kthread_bind_mask+0x60/0x60
? ret_from_fork+0x1f/0x40
```
At last, thanks for Xiao's solution.
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Suggested-by: Xiao Ni <xni@redhat.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reshape request should be blocked with ongoing resync job. In cluster
env, a node can start resync job even if the resync cmd isn't executed
on it, e.g., user executes "mdadm --grow" on node A, sometimes node B
will start resync job. However, current update_raid_disks() only check
local recovery status, which is incomplete. As a result, we see user will
execute "mdadm --grow" successfully on local, while the remote node deny
to do reshape job when it doing resync job. The inconsistent handling
cause array enter unexpected status. If user doesn't observe this issue
and continue executing mdadm cmd, the array doesn't work at last.
Fix this issue by blocking reshape request. When node executes "--grow"
and detects ongoing resync, it should stop and report error to user.
The following script reproduces the issue with ~100% probability.
(two nodes share 3 iSCSI luns: sdg/sdh/sdi. Each lun size is 1GB)
```
# on node1, node2 is the remote node.
ssh root@node2 "mdadm -S --scan"
mdadm -S --scan
for i in {g,h,i};do dd if=/dev/zero of=/dev/sd$i oflag=direct bs=1M \
count=20; done
mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sdg /dev/sdh
ssh root@node2 "mdadm -A /dev/md0 /dev/sdg /dev/sdh"
sleep 5
mdadm --manage --add /dev/md0 /dev/sdi
mdadm --wait /dev/md0
mdadm --grow --raid-devices=3 /dev/md0
mdadm /dev/md0 --fail /dev/sdg
mdadm /dev/md0 --remove /dev/sdg
mdadm --grow --raid-devices=2 /dev/md0
```
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Request coalescing logic uses 'prev_flush_start' as base to
compare the current request start time. 'prev_flush_start' is
updated in other context.
This patch changes this by using ktime comparison base to
'req_start' for better readability of code.
Signed-off-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>