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2021-09-30md: fix a lock order reversal in md_allocChristoph Hellwig1-5/+0
[ Upstream commit 7df835a32a8bedf7ce88efcfa7c9b245b52ff139 ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-09-30treewide: Change list_sort to use const pointersSami Tolvanen1-1/+2
[ 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>
2021-09-18dm crypt: Avoid percpu_counter spinlock contention in crypt_page_alloc()Arne Welzel1-1/+6
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: 5059353df86e ("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>
2021-09-15bcache: add proper error unwinding in bcache_device_initChristoph Hellwig1-5/+11
[ 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>
2021-08-12md/raid10: properly indicate failure when ending a failed write requestWei Shuyu2-4/+2
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: 7cee6d4e6035 ("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>
2021-07-19dm writecache: write at least 4k when committingMikulas Patocka1-1/+5
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>
2021-07-19dm btree remove: assign new_root only when removal succeedsHou Tao1-1/+2
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>
2021-07-19dm writecache: flush origin device when writing and cache is fullMikulas Patocka1-2/+6
commit ee55b92a7391bf871939330f662651b54be51b73 upstream. Commit d53f1fafec9d086f1c5166436abefdaef30e0363 ("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: d53f1fafec9d ("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>
2021-07-19dm zoned: check zone capacityDamien Le Moal1-0/+7
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>
2021-07-19dm writecache: commit just one block, not a full pageMikulas Patocka1-5/+1
[ 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>
2021-07-19dm: Fix dm_accept_partial_bio() relative to zone management commandsDamien Le Moal1-2/+6
[ 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>
2021-07-19dm writecache: don't split bios when overwriting contiguous cache contentMikulas Patocka1-8/+30
[ 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>
2021-07-19dm space maps: don't reset space map allocation cursor when committingJoe Thornber2-2/+16
[ 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>
2021-06-16dm verity: fix require_signatures module_param permissionsJohn Keeping1-1/+1
[ 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>
2021-06-03dm snapshot: properly fix a crash when an origin has no snapshotsMikulas Patocka1-1/+1
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>
2021-05-26dm snapshot: fix crash with transient storage and zero chunk sizeMikulas Patocka1-0/+1
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>
2021-05-14md: Fix missing unused status line of /proc/mdstatJan Glauber1-1/+5
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: 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14md: md_open returns -EBUSY when entering racing areaZhao Heming1-2/+1
commit 6a4db2a60306eb65bfb14ccc9fde035b74a4b4e7 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14md: factor out a mddev_find_locked helper from mddev_findChristoph Hellwig1-13/+19
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>
2021-05-14md: split mddev_findChristoph Hellwig1-5/+19
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 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.
2021-05-14md-cluster: fix use-after-free issue when removing rdevHeming Zhao1-4/+4
commit f7c7a2f9a23e5b6e0f5251f29648d0238bb7757e upstream. md_kick_rdev_from_array will remove rdev, so we should use rdev_for_each_safe to search list. How to trigger: env: Two nodes on kvm-qemu x86_64 VMs (2C2G with 2 iscsi luns). ``` node2=192.168.0.3 for i in {1..20}; do echo ==== $i `date` ====; mdadm -Ss && ssh ${node2} "mdadm -Ss" wipefs -a /dev/sda /dev/sdb mdadm -CR /dev/md0 -b clustered -e 1.2 -n 2 -l 1 /dev/sda \ /dev/sdb --assume-clean ssh ${node2} "mdadm -A /dev/md0 /dev/sda /dev/sdb" mdadm --wait /dev/md0 ssh ${node2} "mdadm --wait /dev/md0" mdadm --manage /dev/md0 --fail /dev/sda --remove /dev/sda sleep 1 done ``` Crash stack: ``` stack segment: 0000 [#1] SMP ... ... RIP: 0010:md_check_recovery+0x1e8/0x570 [md_mod] ... ... RSP: 0018:ffffb149807a7d68 EFLAGS: 00010207 RAX: 0000000000000000 RBX: ffff9d494c180800 RCX: ffff9d490fc01e50 RDX: fffff047c0ed8308 RSI: 0000000000000246 RDI: 0000000000000246 RBP: 6b6b6b6b6b6b6b6b R08: ffff9d490fc01e40 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: ffff9d494c180818 R14: ffff9d493399ef38 R15: ffff9d4933a1d800 FS: 0000000000000000(0000) GS:ffff9d494f700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe68cab9010 CR3: 000000004c6be001 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: raid1d+0x5c/0xd40 [raid1] ? finish_task_switch+0x75/0x2a0 ? lock_timer_base+0x67/0x80 ? try_to_del_timer_sync+0x4d/0x80 ? del_timer_sync+0x41/0x50 ? schedule_timeout+0x254/0x2d0 ? md_start_sync+0xe0/0xe0 [md_mod] ? md_thread+0x127/0x160 [md_mod] md_thread+0x127/0x160 [md_mod] ? wait_woken+0x80/0x80 kthread+0x10d/0x130 ? kthread_park+0xa0/0xa0 ret_from_fork+0x1f/0x40 ``` Fixes: dbb64f8635f5d ("md-cluster: Fix adding of new disk with new reload code") Fixes: 659b254fa7392 ("md-cluster: remove a disk asynchronously from cluster environment") Cc: stable@vger.kernel.org Reviewed-by: Gang He <ghe@suse.com> Signed-off-by: Heming Zhao <heming.zhao@suse.com> Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-14md/bitmap: wait for external bitmap writes to complete during tear downSudhakar Panneerselvam1-0/+2
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>
2021-05-11dm rq: fix double free of blk_mq_tag_set in dev remove after table load failsBenjamin Block1-0/+2
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: 1c357a1e86a4 ("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>
2021-05-11dm integrity: fix missing goto in bitmap_flush_interval error handlingTian Tao1-0/+1
commit 17e9e134a8efabbbf689a0904eee92bb5a868172 upstream. Fixes: 468dfca38b1a ("dm integrity: add a bitmap mode") Cc: stable@vger.kernel.org Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11dm space map common: fix division bug in sm_ll_find_free_block()Joe Thornber1-0/+2
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>
2021-05-11dm persistent data: packed struct should have an aligned() attribute tooJoe Thornber2-6/+6
commit a88b2358f1da2c9f9fcc432f2e0a79617fea397c upstream. Otherwise most non-x86 architectures (e.g. riscv, arm) will resort to byte-by-byte access. Cc: stable@vger.kernel.org Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-05-11dm raid: fix inconclusive reshape layout on fast raid4/5/6 table reload ↵Heinz Mauelshagen1-6/+28
sequences 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>
2021-05-11md/raid1: properly indicate failure when ending a failed write requestPaul Clements1-0/+2
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: eeba6809d8d5 ("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>
2021-04-21dm verity fec: fix misaligned RS roots IOJaegeuk Kim2-3/+9
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>
2021-03-30dm table: Fix zoned model check and zone sectors checkShin'ichiro Kawasaki2-9/+26
[ 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>
2021-03-30dm ioctl: fix out of bounds array access when no devicesMikulas Patocka1-1/+1
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>
2021-03-30dm verity: fix DM_VERITY_OPTS_MAX valueJeongHyeon Lee1-1/+1
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: 843f38d382b1 ("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>
2021-03-09dm verity: fix FEC for RS roots unaligned to block sizeMilan Broz1-11/+12
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>
2021-03-09dm bufio: subtract the number of initial sectors in dm_bufio_get_device_sizeMikulas Patocka1-0/+4
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>
2021-03-04dm era: only resize metadata in preresumeNikos Tsironis1-11/+10
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: eec40579d84873 ("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>
2021-03-04dm era: Reinitialize bitset cache before digesting a new writesetNikos Tsironis1-6/+6
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.