linux/drivers/md, branch v4.8

Merge tag 'md/4.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md

2016-09-13T18:19:52Z

Pull MD fixes from Shaohua Li: "A few bug fixes for MD: - Guoqing fixed a bug compiling md-cluster in kernel - I fixed a potential deadlock in raid5-cache superblock write, a hang in raid5 reshape resume and a race condition introduced in rc4" * tag 'md/4.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md: raid5: fix a small race condition md-cluster: make md-cluster also can work when compiled into kernel raid5: guarantee enough stripes to avoid reshape hang raid5-cache: fix a deadlock in superblock write

raid5: fix a small race condition

2016-09-09T18:09:19Z

commit 5f9d1fde7d54a5(raid5: fix memory leak of bio integrity data) moves bio_reset to bio_endio. But it introduces a small race condition. It does bio_reset after raid5_release_stripe, which could make the stripe reusable and hence reuse the bio just before bio_reset. Moving bio_reset before raid5_release_stripe is called should fix the race. Reported-and-tested-by: Stefan Priebe - Profihost AG Signed-off-by: Shaohua Li

md-cluster: make md-cluster also can work when compiled into kernel

2016-09-08T18:11:27Z

The md-cluster is compiled as module by default, if it is compiled by built-in way, then we can't make md-cluster works. [64782.630008] md/raid1:md127: active with 2 out of 2 mirrors [64782.630528] md-cluster module not found. [64782.630530] md127: Could not setup cluster service (-2) Fixes: edb39c9 ("Introduce md_cluster_operations to handle cluster functions") Cc: stable@vger.kernel.org (v4.1+) Reported-by: Marc Smith Reviewed-by: NeilBrown Signed-off-by: Guoqing Jiang Signed-off-by: Shaohua Li

Merge tag 'dm-4.8-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2016-09-04T00:29:58Z

Pull device mapper fixes from Mike Snitzer: - a stable fix in both DM crypt and DM log-writes for too large bios (as generated by bcache) - two other stable fixes for DM log-writes - a stable fix for a DM crypt bug that could result in freeing pointers from uninitialized memory in the tfm allocation error path - a DM bufio cleanup to discontinue using create_singlethread_workqueue() * tag 'dm-4.8-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm bufio: remove use of deprecated create_singlethread_workqueue() dm crypt: fix free of bad values after tfm allocation failure dm crypt: fix error with too large bios dm log writes: fix check of kthread_run() return value dm log writes: fix bug with too large bios dm log writes: move IO accounting earlier to fix error path

raid5: guarantee enough stripes to avoid reshape hang

2016-08-31T16:05:23Z

If there aren't enough stripes, reshape will hang. We have a check for this in new reshape, but miss it for reshape resume, hence we could see hang in reshape resume. This patch forces enough stripes existed if reshape resumes. Reviewed-by: NeilBrown Signed-off-by: Shaohua Li

raid5-cache: fix a deadlock in superblock write

2016-08-31T16:05:18Z

There is a potential deadlock in superblock write. Discard could zero data, so before discard we must make sure superblock is updated to new log tail. Updating superblock (either directly call md_update_sb() or depend on md thread) must hold reconfig mutex. On the other hand, raid5_quiesce is called with reconfig_mutex hold. The first step of raid5_quiesce() is waitting for all IO finish, hence waitting for reclaim thread, while reclaim thread is calling this function and waitting for reconfig mutex. So there is a deadlock. We workaround this issue with a trylock. The downside of the solution is we could miss discard if we can't take reconfig mutex. But this should happen rarely (mainly in raid array stop), so miss discard shouldn't be a big problem. Cc: NeilBrown Signed-off-by: Shaohua Li

dm bufio: remove use of deprecated create_singlethread_workqueue()

2016-08-30T23:45:20Z

The workqueue "dm_bufio_wq" queues a single work item &dm_bufio_work so it doesn't require execution ordering. Hence, alloc_workqueue() has been used to replace the deprecated create_singlethread_workqueue(). The WQ_MEM_RECLAIM flag has been set since DM requires forward progress under memory pressure. Since there are fixed number of work items, explicit concurrency limit is unnecessary here. Signed-off-by: Bhaktipriya Shridhar Signed-off-by: Mike Snitzer

dm crypt: fix free of bad values after tfm allocation failure

2016-08-30T23:45:19Z

If crypt_alloc_tfms() had to allocate multiple tfms and it failed before the last allocation, then it would call crypt_free_tfms() and could free pointers from uninitialized memory -- due to the crypt_free_tfms() check for non-zero cc->tfms[i]. Fix by allocating zeroed memory. Signed-off-by: Eric Biggers Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org

dm crypt: fix error with too large bios

2016-08-30T23:44:11Z

When dm-crypt processes writes, it allocates a new bio in crypt_alloc_buffer(). The bio is allocated from a bio set and it can have at most BIO_MAX_PAGES vector entries, however the incoming bio can be larger (e.g. if it was allocated by bcache). If the incoming bio is larger, bio_alloc_bioset() fails and an error is returned. To avoid the error, we test for a too large bio in the function crypt_map() and use dm_accept_partial_bio() to split the bio. dm_accept_partial_bio() trims the current bio to the desired size and asks DM core to send another bio with the rest of the data. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org # v3.16+

dm log writes: fix check of kthread_run() return value

2016-08-30T23:41:43Z

The kthread_run() function returns either a valid task_struct or ERR_PTR() value, check for NULL is invalid. This change fixes potential for oops, e.g. in OOM situation. Signed-off-by: Vladimir Zapolskiy Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org