linux/drivers/md, branch v5.9

dm: fix comment in dm_process_bio()

2020-09-21T23:49:15Z

Refer to the correct function (->submit_bio instead of ->queue_bio). Also, add details about why using blk_queue_split() isn't needed for dm_wq_work()'s call to dm_process_bio(). Fixes: c62b37d96b6eb ("block: move ->make_request_fn to struct block_device_operations") Signed-off-by: Mike Snitzer

dm: fix bio splitting and its bio completion order for regular IO

2020-09-21T23:42:20Z

dm_queue_split() is removed because __split_and_process_bio() _must_ handle splitting bios to ensure proper bio submission and completion ordering as a bio is split. Otherwise, multiple recursive calls to ->submit_bio will cause multiple split bios to be allocated from the same ->bio_split mempool at the same time. This would result in deadlock in low memory conditions because no progress could be made (only one bio is available in ->bio_split mempool). This fix has been verified to still fix the loss of performance, due to excess splitting, that commit 120c9257f5f1 provided. Fixes: 120c9257f5f1 ("Revert "dm: always call blk_queue_split() in dm_process_bio()"") Cc: stable@vger.kernel.org # 5.0+, requires custom backport due to 5.9 changes Reported-by: Ming Lei Signed-off-by: Mike Snitzer

dm: Call proper helper to determine dax support

2020-09-20T15:55:09Z

DM was calling generic_fsdax_supported() to determine whether a device referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that they don't have to duplicate common generic checks. High level code should call dax_supported() helper which that calls into appropriate helper for the particular device. This problem manifested itself as kernel messages: dm-3: error: dax access failed (-95) when lvm2-testsuite run in cases where a DM device was stacked on top of another DM device. Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices") Cc: Tested-by: Adrian Huang Signed-off-by: Jan Kara Acked-by: Mike Snitzer Reported-by: kernel test robot Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

dm/dax: Fix table reference counts

2020-09-20T15:33:56Z

A recent fix to the dm_dax_supported() flow uncovered a latent bug. When dm_get_live_table() fails it is still required to drop the srcu_read_lock(). Without this change the lvm2 test-suite triggers this warning: # lvm2-testsuite --only pvmove-abort-all.sh WARNING: lock held when returning to user space! 5.9.0-rc5+ #251 Tainted: G OE ------------------------------------------------ lvm/1318 is leaving the kernel with locks still held! 1 lock held by lvm/1318: #0: ffff9372abb5a340 (&md->io_barrier){....}-{0:0}, at: dm_get_live_table+0x5/0xb0 [dm_mod] ...and later on this hang signature: INFO: task lvm:1344 blocked for more than 122 seconds. Tainted: G OE 5.9.0-rc5+ #251 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:lvm state:D stack: 0 pid: 1344 ppid: 1 flags:0x00004000 Call Trace: __schedule+0x45f/0xa80 ? finish_task_switch+0x249/0x2c0 ? wait_for_completion+0x86/0x110 schedule+0x5f/0xd0 schedule_timeout+0x212/0x2a0 ? __schedule+0x467/0xa80 ? wait_for_completion+0x86/0x110 wait_for_completion+0xb0/0x110 __synchronize_srcu+0xd1/0x160 ? __bpf_trace_rcu_utilization+0x10/0x10 __dm_suspend+0x6d/0x210 [dm_mod] dm_suspend+0xf6/0x140 [dm_mod] Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices") Cc: Cc: Jan Kara Cc: Alasdair Kergon Cc: Mike Snitzer Reported-by: Adrian Huang Reviewed-by: Ira Weiny Tested-by: Adrian Huang Link: https://lore.kernel.org/r/160045867590.25663.7548541079217827340.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

dm thin metadata: Fix use-after-free in dm_bm_set_read_only

2020-09-02T17:38:40Z

The following error ocurred when testing disk online/offline: [ 301.798344] device-mapper: thin: 253:5: aborting current metadata transaction [ 301.848441] device-mapper: thin: 253:5: failed to abort metadata transaction [ 301.849206] Aborting journal on device dm-26-8. [ 301.850489] EXT4-fs error (device dm-26) in __ext4_new_inode:943: Journal has aborted [ 301.851095] EXT4-fs (dm-26): Delayed block allocation failed for inode 398742 at logical offset 181 with max blocks 19 with error 30 [ 301.854476] BUG: KASAN: use-after-free in dm_bm_set_read_only+0x3a/0x40 [dm_persistent_data] Reason is: metadata_operation_failed abort_transaction dm_pool_abort_metadata __create_persistent_data_objects r = __open_or_format_metadata if (r) --> If failed will free pmd->bm but pmd->bm not set NULL dm_block_manager_destroy(pmd->bm); set_pool_mode dm_pool_metadata_read_only(pool->pmd); dm_bm_set_read_only(pmd->bm); --> use-after-free Add checks to see if pmd->bm is NULL in dm_bm_set_read_only and dm_bm_set_read_write functions. If bm is NULL it means creating the bm failed and so dm_bm_is_read_only must return true. Signed-off-by: Ye Bin Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer

dm thin metadata: Avoid returning cmd->bm wild pointer on error

2020-09-02T17:38:31Z

Maybe __create_persistent_data_objects() caller will use PTR_ERR as a pointer, it will lead to some strange things. Signed-off-by: Ye Bin Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer

dm cache metadata: Avoid returning cmd->bm wild pointer on error

2020-09-02T17:38:24Z

Maybe __create_persistent_data_objects() caller will use PTR_ERR as a pointer, it will lead to some strange things. Signed-off-by: Ye Bin Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer

dm integrity: fix error reporting in bitmap mode after creation

2020-09-01T20:41:57Z

The dm-integrity target did not report errors in bitmap mode just after creation. The reason is that the function integrity_recalc didn't clean up ic->recalc_bitmap as it proceeded with recalculation. Fix this by updating the bitmap accordingly -- the double shift serves to rounddown. Signed-off-by: Mikulas Patocka Fixes: 468dfca38b1a ("dm integrity: add a bitmap mode") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Mike Snitzer

dm crypt: Initialize crypto wait structures

2020-09-01T20:41:57Z

Use the DECLARE_CRYPTO_WAIT() macro to properly initialize the crypto wait structures declared on stack before their use with crypto_wait_req(). Fixes: 39d13a1ac41d ("dm crypt: reuse eboiv skcipher for IV generation") Fixes: bbb1658461ac ("dm crypt: Implement Elephant diffuser for Bitlocker compatibility") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Signed-off-by: Mike Snitzer

dm mpath: fix racey management of PG initialization

2020-09-01T20:41:56Z

Commit 935fcc56abc3 ("dm mpath: only flush workqueue when needed") changed flush_multipath_work() to avoid needless workqueue flushing (of a multipath global workqueue). But that change didn't realize the surrounding flush_multipath_work() code should also only run if 'pg_init_in_progress' is set. Fix this by only doing all of flush_multipath_work()'s PG init related work if 'pg_init_in_progress' is set. Otherwise multipath_wait_for_pg_init_completion() will run unconditionally but the preceeding flush_workqueue(kmpath_handlerd) may not. This could lead to deadlock (though only if kmpath_handlerd never runs a corresponding work to decrement 'pg_init_in_progress'). It could also be, though highly unlikely, that the kmpath_handlerd work that does PG init completes before 'pg_init_in_progress' is set, and then an intervening DM table reload's multipath_postsuspend() triggers flush_multipath_work(). Fixes: 935fcc56abc3 ("dm mpath: only flush workqueue when needed") Cc: stable@vger.kernel.org Reported-by: Ben Marzinski Signed-off-by: Mike Snitzer