[ Upstream commit 6fc51504388c1a1a53db8faafe9fff78fccc7c87 ]
Explicitly convert unsigned int in the right of the conditional
expression to int to match the left side operand and the return type,
fixing the following compiler warning:
drivers/md/dm-crypt.c:2593:43: warning: signed and unsigned
type in conditional expression [-Wsign-compare]
Fixes: c538f6ec9f ("dm crypt: add ability to use keys from the kernel key retention service")
Signed-off-by: Aashish Sharma <shraash@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 887554ab96588de2917b6c8c73e552da082e5368 upstream.
When multiple threads to check btree nodes in parallel, the main
thread wait for all threads to stop or CACHE_SET_IO_DISABLE flag:
wait_event_interruptible(check_state->wait,
atomic_read(&check_state->started) == 0 ||
test_bit(CACHE_SET_IO_DISABLE, &c->flags));
However, the bch_btree_node_read and bch_btree_node_read_done
maybe call bch_cache_set_error, then the CACHE_SET_IO_DISABLE
will be set. If the flag already set, the main thread return
error. At the same time, maybe some threads still running and
read NULL pointer, the kernel will crash.
This patch change the event wait condition, the main thread must
wait for all threads to stop.
Fixes: 8e7102273f ("bcache: make bch_btree_check() to be multithreaded")
Signed-off-by: Mingzhe Zou <mingzhe.zou@easystack.cn>
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cc09e8a9dec4f0e8299e80a7a2a8e6f54164a10b upstream.
Commit f6f72f32c2 ("dm integrity: don't replay journal data past the
end of the device") skips journal replay if the target sector points
beyond the end of the device. Unfortunatelly, it doesn't set the
journal entry unused, which resulted in this BUG being triggered:
BUG_ON(!journal_entry_is_unused(je))
Fix this by calling journal_entry_set_unused() for this case.
Fixes: f6f72f32c2 ("dm integrity: don't replay journal data past the end of the device")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Tested-by: Milan Broz <gmazyland@gmail.com>
[snitzer: revised header]
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d751939235b9b7bc4af15f90a3e99288a8b844a7 ]
Make sure ->dax_dev is NULL on error so that the cleanup path doesn't
trip over an ERR_PTR.
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211129102203.2243509-2-hch@lst.de
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 85bca3c05b6cca31625437eedf2060e846c4bbad ]
Corrupt metadata could trigger an out of bounds write.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ad3fc798800fb7ca04c1dfc439dba946818048d8 upstream.
The commit 41d2d848e5 ("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: 41d2d848e5 ("md: improve io stats accounting")
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
[GM: backport to 5.10-stable]
Signed-off-by: Guillaume Morin <guillaume@morinfr.org>
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: d9c0fa509e ("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>
[ Upstream commit 7df835a32a8bedf7ce88efcfa7c9b245b52ff139 ]
Commit b0140891a8 ("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: b0140891a8 ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4f0f586bf0c898233d8f316f471a21db2abd522d ]
list_sort() internally casts the comparison function passed to it
to a different type with constant struct list_head pointers, and
uses this pointer to call the functions, which trips indirect call
Control-Flow Integrity (CFI) checking.
Instead of removing the consts, this change defines the
list_cmp_func_t type and changes the comparison function types of
all list_sort() callers to use const pointers, thus avoiding type
mismatches.
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 528b16bfc3ae5f11638e71b3b63a81f9999df727 upstream.
On systems with many cores using dm-crypt, heavy spinlock contention in
percpu_counter_compare() can be observed when the page allocation limit
for a given device is reached or close to be reached. This is due
to percpu_counter_compare() taking a spinlock to compute an exact
result on potentially many CPUs at the same time.
Switch to non-exact comparison of allocated and allowed pages by using
the value returned by percpu_counter_read_positive() to avoid taking
the percpu_counter spinlock.
This may over/under estimate the actual number of allocated pages by at
most (batch-1) * num_online_cpus().
Currently, batch is bounded by 32. The system on which this issue was
first observed has 256 CPUs and 512GB of RAM. With a 4k page size, this
change may over/under estimate by 31MB. With ~10G (2%) allowed dm-crypt
allocations, this seems an acceptable error. Certainly preferred over
running into the spinlock contention.
This behavior was reproduced on an EC2 c5.24xlarge instance with 96 CPUs
and 192GB RAM as follows, but can be provoked on systems with less CPUs
as well.
* Disable swap
* Tune vm settings to promote regular writeback
$ echo 50 > /proc/sys/vm/dirty_expire_centisecs
$ echo 25 > /proc/sys/vm/dirty_writeback_centisecs
$ echo $((128 * 1024 * 1024)) > /proc/sys/vm/dirty_background_bytes
* Create 8 dmcrypt devices based on files on a tmpfs
* Create and mount an ext4 filesystem on each crypt devices
* Run stress-ng --hdd 8 within one of above filesystems
Total %system usage collected from sysstat goes to ~35%. Write throughput
on the underlying loop device is ~2GB/s. perf profiling an individual
kworker kcryptd thread shows the following profile, indicating spinlock
contention in percpu_counter_compare():
99.98% 0.00% kworker/u193:46 [kernel.kallsyms] [k] ret_from_fork
|
--ret_from_fork
kthread
worker_thread
|
--99.92%--process_one_work
|
|--80.52%--kcryptd_crypt
| |
| |--62.58%--mempool_alloc
| | |
| | --62.24%--crypt_page_alloc
| | |
| | --61.51%--__percpu_counter_compare
| | |
| | --61.34%--__percpu_counter_sum
| | |
| | |--58.68%--_raw_spin_lock_irqsave
| | | |
| | | --58.30%--native_queued_spin_lock_slowpath
| | |
| | --0.69%--cpumask_next
| | |
| | --0.51%--_find_next_bit
| |
| |--10.61%--crypt_convert
| | |
| | |--6.05%--xts_crypt
...
After applying this patch and running the same test, %system usage is
lowered to ~7% and write throughput on the loop device increases
to ~2.7GB/s. perf report shows mempool_alloc() as ~8% rather than ~62%
in the profile and not hitting the percpu_counter() spinlock anymore.
|--8.15%--mempool_alloc
| |
| |--3.93%--crypt_page_alloc
| | |
| | --3.75%--__alloc_pages
| | |
| | --3.62%--get_page_from_freelist
| | |
| | --3.22%--rmqueue_bulk
| | |
| | --2.59%--_raw_spin_lock
| | |
| | --2.57%--native_queued_spin_lock_slowpath
| |
| --3.05%--_raw_spin_lock_irqsave
| |
| --2.49%--native_queued_spin_lock_slowpath
Suggested-by: DJ Gregor <dj@corelight.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Arne Welzel <arne.welzel@corelight.com>
Fixes: 5059353df8 ("dm crypt: limit the number of allocated pages")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 224b0683228c5f332f9cee615d85e75e9a347170 ]
Except for the IDA none of the allocations in bcache_device_init is
unwound on error, fix that.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Coly Li <colyli@suse.de>
Link: https://lore.kernel.org/r/20210809064028.1198327-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5ba03936c05584b6f6f79be5ebe7e5036c1dd252 upstream.
Similar to [1], this patch fixes the same bug in raid10. Also cleanup the
comments.
[1] commit 2417b9869b81 ("md/raid1: properly indicate failure when ending
a failed write request")
Cc: stable@vger.kernel.org
Fixes: 7cee6d4e60 ("md/raid10: end bio when the device faulty")
Signed-off-by: Wei Shuyu <wsy@dogben.com>
Acked-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 867de40c4c23e6d7f89f9ce4272a5d1b1484c122 upstream.
SSDs perform badly with sub-4k writes (because they perfrorm
read-modify-write internally), so make sure writecache writes at least
4k when committing.
Fixes: 991bd8d7bc78 ("dm writecache: commit just one block, not a full page")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b6e58b5466b2959f83034bead2e2e1395cca8aeb upstream.
remove_raw() in dm_btree_remove() may fail due to IO read error
(e.g. read the content of origin block fails during shadowing),
and the value of shadow_spine::root is uninitialized, but
the uninitialized value is still assign to new_root in the
end of dm_btree_remove().
For dm-thin, the value of pmd->details_root or pmd->root will become
an uninitialized value, so if trying to read details_info tree again
out-of-bound memory may occur as showed below:
general protection fault, probably for non-canonical address 0x3fdcb14c8d7520
CPU: 4 PID: 515 Comm: dmsetup Not tainted 5.13.0-rc6
Hardware name: QEMU Standard PC
RIP: 0010:metadata_ll_load_ie+0x14/0x30
Call Trace:
sm_metadata_count_is_more_than_one+0xb9/0xe0
dm_tm_shadow_block+0x52/0x1c0
shadow_step+0x59/0xf0
remove_raw+0xb2/0x170
dm_btree_remove+0xf4/0x1c0
dm_pool_delete_thin_device+0xc3/0x140
pool_message+0x218/0x2b0
target_message+0x251/0x290
ctl_ioctl+0x1c4/0x4d0
dm_ctl_ioctl+0xe/0x20
__x64_sys_ioctl+0x7b/0xb0
do_syscall_64+0x40/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixing it by only assign new_root when removal succeeds
Signed-off-by: Hou Tao <houtao1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ee55b92a7391bf871939330f662651b54be51b73 upstream.
Commit d53f1fafec ("dm writecache: do
direct write if the cache is full") changed dm-writecache, so that it
writes directly to the origin device if the cache is full.
Unfortunately, it doesn't forward flush requests to the origin device,
so that there is a bug where flushes are being ignored.
Fix this by adding missing flush forwarding.
For PMEM mode, we fix this bug by disabling direct writes to the origin
device, because it performs better.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: d53f1fafec ("dm writecache: do direct write if the cache is full")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bab68499428ed934f0493ac74197ed6f36204260 upstream.
The dm-zoned target cannot support zoned block devices with zones that
have a capacity smaller than the zone size (e.g. NVMe zoned namespaces)
due to the current chunk zone mapping implementation as it is assumed
that zones and chunks have the same size with all blocks usable.
If a zoned drive is found to have zones with a capacity different from
the zone size, fail the target initialization.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 991bd8d7bc78966b4dc427b53a144f276bffcd52 ]
Some architectures have pages larger than 4k and committing a full
page causes needless overhead.
Fix this by writing a single block when committing the superblock.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6842d264aa5205da338b6dcc6acfa2a6732558f1 ]
Fix dm_accept_partial_bio() to actually check that zone management
commands are not passed as explained in the function documentation
comment. Also, since a zone append operation cannot be split, add
REQ_OP_ZONE_APPEND as a forbidden command.
White lines are added around the group of BUG_ON() calls to make the
code more legible.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ee50cc19d80e9b9a8283d1fb517a778faf2f6899 ]
If dm-writecache overwrites existing cached data, it splits the
incoming bio into many block-sized bios. The I/O scheduler does merge
these bios into one large request but this needless splitting and
merging causes performance degradation.
Fix this by avoiding bio splitting if the cache target area that is
being overwritten is contiguous.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5faafc77f7de69147d1e818026b9a0cbf036a7b2 ]
Current commit code resets the place where the search for free blocks
will begin back to the start of the metadata device. There are a couple
of repercussions to this:
- The first allocation after the commit is likely to take longer than
normal as it searches for a free block in an area that is likely to
have very few free blocks (if any).
- Any free blocks it finds will have been recently freed. Reusing them
means we have fewer old copies of the metadata to aid recovery from
hardware error.
Fix these issues by leaving the cursor alone, only resetting when the
search hits the end of the metadata device.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0c1f3193b1cdd21e7182f97dc9bca7d284d18a15 ]
The third parameter of module_param() is permissions for the sysfs node
but it looks like it is being used as the initial value of the parameter
here. In fact, false here equates to omitting the file from sysfs and
does not affect the value of require_signatures.
Making the parameter writable is not simple because going from
false->true is fine but it should not be possible to remove the
requirement to verify a signature. But it can be useful to inspect the
value of this parameter from userspace, so change the permissions to
make a read-only file in sysfs.
Signed-off-by: John Keeping <john@metanate.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7e768532b2396bcb7fbf6f82384b85c0f1d2f197 upstream.
If an origin target has no snapshots, o->split_boundary is set to 0.
This causes BUG_ON(sectors <= 0) in block/bio.c:bio_split().
Fix this by initializing chunk_size, and in turn split_boundary, to
rounddown_pow_of_two(UINT_MAX) -- the largest power of two that fits
into "unsigned" type.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c699a0db2d62e3bbb7f0bf35c87edbc8d23e3062 upstream.
The following commands will crash the kernel:
modprobe brd rd_size=1048576
dmsetup create o --table "0 `blockdev --getsize /dev/ram0` snapshot-origin /dev/ram0"
dmsetup create s --table "0 `blockdev --getsize /dev/ram0` snapshot /dev/ram0 /dev/ram1 N 0"
The reason is that when we test for zero chunk size, we jump to the label
bad_read_metadata without setting the "r" variable. The function
snapshot_ctr destroys all the structures and then exits with "r == 0". The
kernel then crashes because it falsely believes that snapshot_ctr
succeeded.
In order to fix the bug, we set the variable "r" to -EINVAL.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7abfabaf5f805f5171d133ce6af9b65ab766e76a upstream.
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: 1f4aace60b ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6a4db2a60306eb65bfb14ccc9fde035b74a4b4e7 upstream.
commit d3374825ce ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8b57251f9a91f5e5a599de7549915d2d226cc3af upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 65aa97c4d2bfd76677c211b9d03ef05a98c6d68e upstream.
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 d3374825ce ("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.
commit 404a8ef512587b2460107d3272c17a89aef75edf upstream.
NULL pointer dereference was observed in super_written() when it tries
to access the mddev structure.
[The below stack trace is from an older kernel, but the problem described
in this patch applies to the mainline kernel.]
[ 1194.474861] task: ffff8fdd20858000 task.stack: ffffb99d40790000
[ 1194.488000] RIP: 0010:super_written+0x29/0xe1
[ 1194.499688] RSP: 0018:ffff8ffb7fcc3c78 EFLAGS: 00010046
[ 1194.512477] RAX: 0000000000000000 RBX: ffff8ffb7bf4a000 RCX: ffff8ffb78991048
[ 1194.527325] RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffff8ffb56b8a200
[ 1194.542576] RBP: ffff8ffb7fcc3c90 R08: 000000000000000b R09: 0000000000000000
[ 1194.558001] R10: ffff8ffb56b8a298 R11: 0000000000000000 R12: ffff8ffb56b8a200
[ 1194.573070] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
[ 1194.588117] FS: 0000000000000000(0000) GS:ffff8ffb7fcc0000(0000) knlGS:0000000000000000
[ 1194.604264] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1194.617375] CR2: 00000000000002b8 CR3: 00000021e040a002 CR4: 00000000007606e0
[ 1194.632327] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1194.647865] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1194.663316] PKRU: 55555554
[ 1194.674090] Call Trace:
[ 1194.683735] <IRQ>
[ 1194.692948] bio_endio+0xae/0x135
[ 1194.703580] blk_update_request+0xad/0x2fa
[ 1194.714990] blk_update_bidi_request+0x20/0x72
[ 1194.726578] __blk_end_bidi_request+0x2c/0x4d
[ 1194.738373] __blk_end_request_all+0x31/0x49
[ 1194.749344] blk_flush_complete_seq+0x377/0x383
[ 1194.761550] flush_end_io+0x1dd/0x2a7
[ 1194.772910] blk_finish_request+0x9f/0x13c
[ 1194.784544] scsi_end_request+0x180/0x25c
[ 1194.796149] scsi_io_completion+0xc8/0x610
[ 1194.807503] scsi_finish_command+0xdc/0x125
[ 1194.818897] scsi_softirq_done+0x81/0xde
[ 1194.830062] blk_done_softirq+0xa4/0xcc
[ 1194.841008] __do_softirq+0xd9/0x29f
[ 1194.851257] irq_exit+0xe6/0xeb
[ 1194.861290] do_IRQ+0x59/0xe3
[ 1194.871060] common_interrupt+0x1c6/0x382
[ 1194.881988] </IRQ>
[ 1194.890646] RIP: 0010:cpuidle_enter_state+0xdd/0x2a5
[ 1194.902532] RSP: 0018:ffffb99d40793e68 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff43
[ 1194.917317] RAX: ffff8ffb7fce27c0 RBX: ffff8ffb7fced800 RCX: 000000000000001f
[ 1194.932056] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
[ 1194.946428] RBP: ffffb99d40793ea0 R08: 0000000000000004 R09: 0000000000002ed2
[ 1194.960508] R10: 0000000000002664 R11: 0000000000000018 R12: 0000000000000003
[ 1194.974454] R13: 000000000000000b R14: ffffffff925715a0 R15: 0000011610120d5a
[ 1194.988607] ? cpuidle_enter_state+0xcc/0x2a5
[ 1194.999077] cpuidle_enter+0x17/0x19
[ 1195.008395] call_cpuidle+0x23/0x3a
[ 1195.017718] do_idle+0x172/0x1d5
[ 1195.026358] cpu_startup_entry+0x73/0x75
[ 1195.035769] start_secondary+0x1b9/0x20b
[ 1195.044894] secondary_startup_64+0xa5/0xa5
[ 1195.084921] RIP: super_written+0x29/0xe1 RSP: ffff8ffb7fcc3c78
[ 1195.096354] CR2: 00000000000002b8
bio in the above stack is a bitmap write whose completion is invoked after
the tear down sequence sets the mddev structure to NULL in rdev.
During tear down, there is an attempt to flush the bitmap writes, but for
external bitmaps, there is no explicit wait for all the bitmap writes to
complete. For instance, md_bitmap_flush() is called to flush the bitmap
writes, but the last call to md_bitmap_daemon_work() in md_bitmap_flush()
could generate new bitmap writes for which there is no explicit wait to
complete those writes. The call to md_bitmap_update_sb() will return
simply for external bitmaps and the follow-up call to md_update_sb() is
conditional and may not get called for external bitmaps. This results in a
kernel panic when the completion routine, super_written() is called which
tries to reference mddev in the rdev that has been set to
NULL(in unbind_rdev_from_array() by tear down sequence).
The solution is to call md_super_wait() for external bitmaps after the
last call to md_bitmap_daemon_work() in md_bitmap_flush() to ensure there
are no pending bitmap writes before proceeding with the tear down.
Cc: stable@vger.kernel.org
Signed-off-by: Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>
Reviewed-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8e947c8f4a5620df77e43c9c75310dc510250166 upstream.
When loading a device-mapper table for a request-based mapped device,
and the allocation/initialization of the blk_mq_tag_set for the device
fails, a following device remove will cause a double free.
E.g. (dmesg):
device-mapper: core: Cannot initialize queue for request-based dm-mq mapped device
device-mapper: ioctl: unable to set up device queue for new table.
Unable to handle kernel pointer dereference in virtual kernel address space
Failing address: 0305e098835de000 TEID: 0305e098835de803
Fault in home space mode while using kernel ASCE.
AS:000000025efe0007 R3:0000000000000024
Oops: 0038 ilc:3 [#1] SMP
Modules linked in: ... lots of modules ...
Supported: Yes, External
CPU: 0 PID: 7348 Comm: multipathd Kdump: loaded Tainted: G W X 5.3.18-53-default #1 SLE15-SP3
Hardware name: IBM 8561 T01 7I2 (LPAR)
Krnl PSW : 0704e00180000000 000000025e368eca (kfree+0x42/0x330)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 000000000000004a 000000025efe5230 c1773200d779968d 0000000000000000
000000025e520270 000000025e8d1b40 0000000000000003 00000007aae10000
000000025e5202a2 0000000000000001 c1773200d779968d 0305e098835de640
00000007a8170000 000003ff80138650 000000025e5202a2 000003e00396faa8
Krnl Code: 000000025e368eb8: c4180041e100 lgrl %r1,25eba50b8
000000025e368ebe: ecba06b93a55 risbg %r11,%r10,6,185,58
#000000025e368ec4: e3b010000008 ag %r11,0(%r1)
>000000025e368eca: e310b0080004 lg %r1,8(%r11)
000000025e368ed0: a7110001 tmll %r1,1
000000025e368ed4: a7740129 brc 7,25e369126
000000025e368ed8: e320b0080004 lg %r2,8(%r11)
000000025e368ede: b904001b lgr %r1,%r11
Call Trace:
[<000000025e368eca>] kfree+0x42/0x330
[<000000025e5202a2>] blk_mq_free_tag_set+0x72/0xb8
[<000003ff801316a8>] dm_mq_cleanup_mapped_device+0x38/0x50 [dm_mod]
[<000003ff80120082>] free_dev+0x52/0xd0 [dm_mod]
[<000003ff801233f0>] __dm_destroy+0x150/0x1d0 [dm_mod]
[<000003ff8012bb9a>] dev_remove+0x162/0x1c0 [dm_mod]
[<000003ff8012a988>] ctl_ioctl+0x198/0x478 [dm_mod]
[<000003ff8012ac8a>] dm_ctl_ioctl+0x22/0x38 [dm_mod]
[<000000025e3b11ee>] ksys_ioctl+0xbe/0xe0
[<000000025e3b127a>] __s390x_sys_ioctl+0x2a/0x40
[<000000025e8c15ac>] system_call+0xd8/0x2c8
Last Breaking-Event-Address:
[<000000025e52029c>] blk_mq_free_tag_set+0x6c/0xb8
Kernel panic - not syncing: Fatal exception: panic_on_oops
When allocation/initialization of the blk_mq_tag_set fails in
dm_mq_init_request_queue(), it is uninitialized/freed, but the pointer
is not reset to NULL; so when dev_remove() later gets into
dm_mq_cleanup_mapped_device() it sees the pointer and tries to
uninitialize and free it again.
Fix this by setting the pointer to NULL in dm_mq_init_request_queue()
error-handling. Also set it to NULL in dm_mq_cleanup_mapped_device().
Cc: <stable@vger.kernel.org> # 4.6+
Fixes: 1c357a1e86 ("dm: allocate blk_mq_tag_set rather than embed in mapped_device")
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5208692e80a1f3c8ce2063a22b675dd5589d1d80 upstream.
This division bug meant the search for free metadata space could skip
the final allocation bitmap's worth of entries. Fix affects DM thinp,
cache and era targets.
Cc: stable@vger.kernel.org
Signed-off-by: Joe Thornber <ejt@redhat.com>
Tested-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f99a8e4373eeacb279bc9696937a55adbff7a28a upstream.
If fast table reloads occur during an ongoing reshape of raid4/5/6
devices the target may race reading a superblock vs the the MD resync
thread; causing an inconclusive reshape state to be read in its
constructor.
lvm2 test lvconvert-raid-reshape-stripes-load-reload.sh can cause
BUG_ON() to trigger in md_run(), e.g.:
"kernel BUG at drivers/md/raid5.c:7567!".
Scenario triggering the bug:
1. the MD sync thread calls end_reshape() from raid5_sync_request()
when done reshaping. However end_reshape() _only_ updates the
reshape position to MaxSector keeping the changed layout
configuration though (i.e. any delta disks, chunk sector or RAID
algorithm changes). That inconclusive configuration is stored in
the superblock.
2. dm-raid constructs a mapping, loading named inconsistent superblock
as of step 1 before step 3 is able to finish resetting the reshape
state completely, and calls md_run() which leads to mentioned bug
in raid5.c.
3. the MD RAID personality's finish_reshape() is called; which resets
the reshape information on chunk sectors, delta disks, etc. This
explains why the bug is rarely seen on multi-core machines, as MD's
finish_reshape() superblock update races with the dm-raid
constructor's superblock load in step 2.
Fix identifies inconclusive superblock content in the dm-raid
constructor and resets it before calling md_run(), factoring out
identifying checks into rs_is_layout_change() to share in existing
rs_reshape_requested() and new rs_reset_inclonclusive_reshape(). Also
enhance a comment and remove an empty line.
Cc: stable@vger.kernel.org
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2417b9869b81882ab90fd5ed1081a1cb2d4db1dd upstream.
This patch addresses a data corruption bug in raid1 arrays using bitmaps.
Without this fix, the bitmap bits for the failed I/O end up being cleared.
Since we are in the failure leg of raid1_end_write_request, the request
either needs to be retried (R1BIO_WriteError) or failed (R1BIO_Degraded).
Fixes: eeba6809d8 ("md/raid1: end bio when the device faulty")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Paul Clements <paul.clements@us.sios.com>
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 8ca7cab82bda4eb0b8064befeeeaa38106cac637 upstream.
commit df7b59ba9245 ("dm verity: fix FEC for RS roots unaligned to
block size") introduced the possibility for misaligned roots IO
relative to the underlying device's logical block size. E.g. Android's
default RS roots=2 results in dm_bufio->block_size=1024, which causes
the following EIO if the logical block size of the device is 4096,
given v->data_dev_block_bits=12:
E sd 0 : 0:0:0: [sda] tag#30 request not aligned to the logical block size
E blk_update_request: I/O error, dev sda, sector 10368424 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 0
E device-mapper: verity-fec: 254:8: FEC 9244672: parity read failed (block 18056): -5
Fix this by onlu using f->roots for dm_bufio blocksize IFF it is
aligned to v->data_dev_block_bits.
Fixes: df7b59ba9245 ("dm verity: fix FEC for RS roots unaligned to block size")
Cc: stable@vger.kernel.org
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2d669ceb69c276f7637cf760287ca4187add082e ]
Commit 24f6b6036c9e ("dm table: fix zoned iterate_devices based device
capability checks") triggered dm table load failure when dm-zoned device
is set up for zoned block devices and a regular device for cache.
The commit inverted logic of two callback functions for iterate_devices:
device_is_zoned_model() and device_matches_zone_sectors(). The logic of
device_is_zoned_model() was inverted then all destination devices of all
targets in dm table are required to have the expected zoned model. This
is fine for dm-linear, dm-flakey and dm-crypt on zoned block devices
since each target has only one destination device. However, this results
in failure for dm-zoned with regular cache device since that target has
both regular block device and zoned block devices.
As for device_matches_zone_sectors(), the commit inverted the logic to
require all zoned block devices in each target have the specified
zone_sectors. This check also fails for regular block device which does
not have zones.
To avoid the check failures, fix the zone model check and the zone
sectors check. For zone model check, introduce the new feature flag
DM_TARGET_MIXED_ZONED_MODEL, and set it to dm-zoned target. When the
target has this flag, allow it to have destination devices with any
zoned model. For zone sectors check, skip the check if the destination
device is not a zoned block device. Also add comments and improve an
error message to clarify expectations to the two checks.
Fixes: 24f6b6036c9e ("dm table: fix zoned iterate_devices based device capability checks")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4edbe1d7bcffcd6269f3b5eb63f710393ff2ec7a upstream.
If there are not any dm devices, we need to zero the "dev" argument in
the first structure dm_name_list. However, this can cause out of
bounds write, because the "needed" variable is zero and len may be
less than eight.
Fix this bug by reporting DM_BUFFER_FULL_FLAG if the result buffer is
too small to hold the "nl->dev" value.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 160f99db943224e55906dd83880da1a704c6e6b9 upstream.
Three optional parameters must be accepted at once in a DM verity table, e.g.:
(verity_error_handling_mode) (ignore_zero_block) (check_at_most_once)
Fix this to be possible by incrementing DM_VERITY_OPTS_MAX.
Signed-off-by: JeongHyeon Lee <jhs2.lee@samsung.com>
Fixes: 843f38d382 ("dm verity: add 'check_at_most_once' option to only validate hashes once")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit df7b59ba9245c4a3115ebaa905e3e5719a3810da upstream.
Optional Forward Error Correction (FEC) code in dm-verity uses
Reed-Solomon code and should support roots from 2 to 24.
The error correction parity bytes (of roots lengths per RS block) are
stored on a separate device in sequence without any padding.
Currently, to access FEC device, the dm-verity-fec code uses dm-bufio
client with block size set to verity data block (usually 4096 or 512
bytes).
Because this block size is not divisible by some (most!) of the roots
supported lengths, data repair cannot work for partially stored parity
bytes.
This fix changes FEC device dm-bufio block size to "roots << SECTOR_SHIFT"
where we can be sure that the full parity data is always available.
(There cannot be partial FEC blocks because parity must cover whole
sectors.)
Because the optional FEC starting offset could be unaligned to this
new block size, we have to use dm_bufio_set_sector_offset() to
configure it.
The problem is easily reproduced using veritysetup, e.g. for roots=13:
# create verity device with RS FEC
dd if=/dev/urandom of=data.img bs=4096 count=8 status=none
veritysetup format data.img hash.img --fec-device=fec.img --fec-roots=13 | awk '/^Root hash/{ print $3 }' >roothash
# create an erasure that should be always repairable with this roots setting
dd if=/dev/zero of=data.img conv=notrunc bs=1 count=8 seek=4088 status=none
# try to read it through dm-verity
veritysetup open data.img test hash.img --fec-device=fec.img --fec-roots=13 $(cat roothash)
dd if=/dev/mapper/test of=/dev/null bs=4096 status=noxfer
# wait for possible recursive recovery in kernel
udevadm settle
veritysetup close test
With this fix, errors are properly repaired.
device-mapper: verity-fec: 7:1: FEC 0: corrected 8 errors
...
Without it, FEC code usually ends on unrecoverable failure in RS decoder:
device-mapper: verity-fec: 7:1: FEC 0: failed to correct: -74
...
This problem is present in all kernels since the FEC code's
introduction (kernel 4.5).
It is thought that this problem is not visible in Android ecosystem
because it always uses a default RS roots=2.
Depends-on: a14e5ec66a7a ("dm bufio: subtract the number of initial sectors in dm_bufio_get_device_size")
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Tested-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Cc: stable@vger.kernel.org # 4.5+
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a14e5ec66a7a66e57b24e2469f9212a78460207e upstream.
dm_bufio_get_device_size returns the device size in blocks. Before
returning the value, we must subtract the nubmer of starting
sectors. The number of starting sectors may not be divisible by block
size.
Note that currently, no target is using dm_bufio_set_sector_offset and
dm_bufio_get_device_size simultaneously, so this change has no effect.
However, an upcoming dm-verity-fec fix needs this change.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Milan Broz <gmazyland@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cca2c6aebe86f68103a8615074b3578e854b5016 upstream.
Metadata resize shouldn't happen in the ctr. The ctr loads a temporary
(inactive) table that will only become active upon resume. That is why
resize should always be done in terms of resume. Otherwise a load (ctr)
whose inactive table never becomes active will incorrectly resize the
metadata.
Also, perform the resize directly in preresume, instead of using the
worker to do it.
The worker might run other metadata operations, e.g., it could start
digestion, before resizing the metadata. These operations will end up
using the old size.
This could lead to errors, like:
device-mapper: era: metadata_digest_transcribe_writeset: dm_array_set_value failed
device-mapper: era: process_old_eras: digest step failed, stopping digestion
The reason of the above error is that the worker started the digestion
of the archived writeset using the old, larger size.
As a result, metadata_digest_transcribe_writeset tried to write beyond
the end of the era array.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2524933307fd0036d5c32357c693c021ab09a0b0 upstream.
In case of devices with at most 64 blocks, the digestion of consecutive
eras uses the writeset of the first era as the writeset of all eras to
digest, leading to lost writes. That is, we lose the information about
what blocks were written during the affected eras.
The digestion code uses a dm_disk_bitset object to access the archived
writesets. This structure includes a one word (64-bit) cache to reduce
the number of array lookups.
This structure is initialized only once, in metadata_digest_start(),
when we kick off digestion.
But, when we insert a new writeset into the writeset tree, before the
digestion of the previous writeset is done, or equivalently when there
are multiple writesets in the writeset tree to digest, then all these
writesets are digested using the same cache and the cache is not
re-initialized when moving from one writeset to the next.
For devices with more than 64 blocks, i.e., the size of the cache, the
cache is indirectly invalidated when we move to a next set of blocks, so
we avoid the bug.
But for devices with at most 64 blocks we end up using the same cached
data for digesting all archived writesets, i.e., the cache is loaded
when digesting the first writeset and it never gets reloaded, until the
digestion is done.
As a result, the writeset of the first era to digest is used as the
writeset of all the following archived eras, leading to lost writes.
Fix this by reinitializing the dm_disk_bitset structure, and thus
invalidating the cache, every time the digestion code starts digesting a
new writeset.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64f2d15afe7b336aafebdcd14cc835ecf856df4b upstream.
Fix the writeset tree equality test function to use the right value size
when comparing two btree values.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 904e6b266619c2da5c58b5dce14ae30629e39645 upstream.
Deallocate the memory allocated for the in-core bitsets when destroying
the target and in error paths.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c8e846ff93d5eaa5384f6f325a1687ac5921aade upstream.
dm-era doesn't support changing the data block size of existing devices,
so check explicitly that the requested block size for a new target
matches the one stored in the metadata.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Reviewed-by: Ming-Hung Tsai <mtsai@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2099b145d77c1d53f5711f029c37cc537897cee6 upstream.
In case of a system crash, dm-era might fail to mark blocks as written
in its metadata, although the corresponding writes to these blocks were
passed down to the origin device and completed successfully.
Consider the following sequence of events:
1. We write to a block that has not been yet written in the current era
2. era_map() checks the in-core bitmap for the current era and sees
that the block is not marked as written.
3. The write is deferred for submission after the metadata have been
updated and committed.
4. The worker thread processes the deferred write
(process_deferred_bios()) and marks the block as written in the
in-core bitmap, **before** committing the metadata.
5. The worker thread starts committing the metadata.
6. We do more writes that map to the same block as the write of step (1)
7. era_map() checks the in-core bitmap and sees that the block is marked
as written, **although the metadata have not been committed yet**.
8. These writes are passed down to the origin device immediately and the
device reports them as completed.
9. The system crashes, e.g., power failure, before the commit from step
(5) finishes.
When the system recovers and we query the dm-era target for the list of
written blocks it doesn't report the aforementioned block as written,
although the writes of step (6) completed successfully.
The issue is that era_map() decides whether to defer or not a write
based on non committed information. The root cause of the bug is that we
update the in-core bitmap, **before** committing the metadata.
Fix this by updating the in-core bitmap **after** successfully
committing the metadata.
Fixes: eec40579d8 ("dm: add era target")
Cc: stable@vger.kernel.org # v3.15+
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
