user/sven/linux.git/block, branch v4.18.11

blk-mq: avoid to synchronize rcu inside blk_cleanup_queue()

2018-09-26T06:39:43Z

[ Upstream commit 1311326cf4755c7ffefd20f576144ecf46d9906b ] SCSI probing may synchronously create and destroy a lot of request_queues for non-existent devices. Any synchronize_rcu() in queue creation or destroy path may introduce long latency during booting, see detailed description in comment of blk_register_queue(). This patch removes one synchronize_rcu() inside blk_cleanup_queue() for this case, commit c2856ae2f315d75(blk-mq: quiesce queue before freeing queue) needs synchronize_rcu() for implementing blk_mq_quiesce_queue(), but when queue isn't initialized, it isn't necessary to do that since only pass-through requests are involved, no original issue in scsi_execute() at all. Without this patch and previous one, it may take more 20+ seconds for virtio-scsi to complete disk probe. With the two patches, the time becomes less than 100ms. Fixes: c2856ae2f315d75 ("blk-mq: quiesce queue before freeing queue") Reported-by: Andrew Jones Cc: Omar Sandoval Cc: Bart Van Assche Cc: linux-scsi@vger.kernel.org Cc: "Martin K. Petersen" Cc: Christoph Hellwig Tested-by: Andrew Jones Signed-off-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

blk-mq: only attempt to merge bio if there is rq in sw queue

2018-09-26T06:39:43Z

[ Upstream commit b04f50ab8a74129b3041a2836c33c916be3c6667 ] Only attempt to merge bio iff the ctx->rq_list isn't empty, because: 1) for high-performance SSD, most of times dispatch may succeed, then there may be nothing left in ctx->rq_list, so don't try to merge over sw queue if it is empty, then we can save one acquiring of ctx->lock 2) we can't expect good merge performance on per-cpu sw queue, and missing one merge on sw queue won't be a big deal since tasks can be scheduled from one CPU to another. Cc: Laurence Oberman Cc: Omar Sandoval Cc: Bart Van Assche Tested-by: Kashyap Desai Reported-by: Kashyap Desai Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

block: allow max_discard_segments to be stacked

2018-09-26T06:39:23Z

[ Upstream commit 42c9cdfe1e11e083dceb0f0c4977b758cf7403b9 ] Set max_discard_segments to USHRT_MAX in blk_set_stacking_limits() so that blk_stack_limits() can stack up this limit for stacked devices. before: $ cat /sys/block/nvme0n1/queue/max_discard_segments 256 $ cat /sys/block/dm-0/queue/max_discard_segments 1 after: $ cat /sys/block/nvme0n1/queue/max_discard_segments 256 $ cat /sys/block/dm-0/queue/max_discard_segments 256 Fixes: 1e739730c5b9e ("block: optionally merge discontiguous discard bios into a single request") Reviewed-by: Christoph Hellwig Signed-off-by: Mike Snitzer Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

partitions/aix: fix usage of uninitialized lv_info and lvname structures

2018-09-19T20:41:35Z

[ Upstream commit 14cb2c8a6c5dae57ee3e2da10fa3db2b9087e39e ] The if-block that sets a successful return value in aix_partition() uses 'lvip[].pps_per_lv' and 'n[].name' potentially uninitialized. For example, if 'numlvs' is zero or alloc_lvn() fails, neither is initialized, but are used anyway if alloc_pvd() succeeds after it. So, make the alloc_pvd() call conditional on their initialization. This has been hit when attaching an apparently corrupted/stressed AIX LUN, misleading the kernel to pr_warn() invalid data and hang. [...] partition (null) (11 pp's found) is not contiguous [...] partition (null) (2 pp's found) is not contiguous [...] partition (null) (3 pp's found) is not contiguous [...] partition (null) (64 pp's found) is not contiguous Fixes: 6ceea22bbbc8 ("partitions: add aix lvm partition support files") Signed-off-by: Mauricio Faria de Oliveira Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

partitions/aix: append null character to print data from disk

2018-09-19T20:41:35Z

[ Upstream commit d43fdae7bac2def8c4314b5a49822cb7f08a45f1 ] Even if properly initialized, the lvname array (i.e., strings) is read from disk, and might contain corrupt data (e.g., lack the null terminating character for strings). So, make sure the partition name string used in pr_warn() has the null terminating character. Fixes: 6ceea22bbbc8 ("partitions: add aix lvm partition support files") Suggested-by: Daniel J. Axtens Signed-off-by: Mauricio Faria de Oliveira Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

blk-mq: fix updating tags depth

2018-09-19T20:41:26Z

[ Upstream commit 75d6e175fc511e95ae3eb8f708680133bc211ed3 ] The passed 'nr' from userspace represents the total depth, meantime inside 'struct blk_mq_tags', 'nr_tags' stores the total tag depth, and 'nr_reserved_tags' stores the reserved part. There are two issues in blk_mq_tag_update_depth() now: 1) for growing tags, we should have used the passed 'nr', and keep the number of reserved tags not changed. 2) the passed 'nr' should have been used for checking against 'tags->nr_tags', instead of number of the normal part. This patch fixes the above two cases, and avoids kernel crash caused by wrong resizing sbitmap queue. Cc: "Ewan D. Milne" Cc: Christoph Hellwig Cc: Bart Van Assche Cc: Omar Sandoval Tested by: Marco Patalano Signed-off-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

block: bfq: swap puts in bfqg_and_blkg_put

2018-09-19T20:41:20Z

commit d5274b3cd6a814ccb2f56d81ee87cbbf51bd4cf7 upstream. Fix trivial use-after-free. This could be last reference to bfqg. Fixes: 8f9bebc33dd7 ("block, bfq: access and cache blkg data only when safe") Acked-by: Paolo Valente Signed-off-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block: don't warn when doing fsync on read-only devices

2018-09-19T20:41:20Z

commit 8b2ded1c94c06f841f8c1612bcfa33c85012a36b upstream. It is possible to call fsync on a read-only handle (for example, fsck.ext2 does it when doing read-only check), and this call results in kernel warning. The patch b089cfd95d32 ("block: don't warn for flush on read-only device") attempted to disable the warning, but it is buggy and it doesn't (op_is_flush tests flags, but bio_op strips off the flags). Signed-off-by: Mikulas Patocka Fixes: 721c7fc701c7 ("block: fail op_is_write() requests to read-only partitions") Cc: stable@vger.kernel.org # 4.18 Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

cfq: Suppress compiler warnings about comparisons

2018-09-15T07:46:53Z

[ Upstream commit f7ecb1b109da1006a08d5675debe60990e824432 ] This patch does not change any functionality but avoids that gcc reports the following warnings when building with W=1: block/cfq-iosched.c: In function ?cfq_back_seek_max_store?: block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4756:1: note: in expansion of macro ?STORE_FUNCTION? STORE_FUNCTION(cfq_back_seek_max_store, &cfqd->cfq_back_max, 0, UINT_MAX, 0); ^~~~~~~~~~~~~~ block/cfq-iosched.c: In function ?cfq_slice_idle_store?: block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4759:1: note: in expansion of macro ?STORE_FUNCTION? STORE_FUNCTION(cfq_slice_idle_store, &cfqd->cfq_slice_idle, 0, UINT_MAX, 1); ^~~~~~~~~~~~~~ block/cfq-iosched.c: In function ?cfq_group_idle_store?: block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4760:1: note: in expansion of macro ?STORE_FUNCTION? STORE_FUNCTION(cfq_group_idle_store, &cfqd->cfq_group_idle, 0, UINT_MAX, 1); ^~~~~~~~~~~~~~ block/cfq-iosched.c: In function ?cfq_low_latency_store?: block/cfq-iosched.c:4741:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4765:1: note: in expansion of macro ?STORE_FUNCTION? STORE_FUNCTION(cfq_low_latency_store, &cfqd->cfq_latency, 0, 1, 0); ^~~~~~~~~~~~~~ block/cfq-iosched.c: In function ?cfq_slice_idle_us_store?: block/cfq-iosched.c:4775:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4782:1: note: in expansion of macro ?USEC_STORE_FUNCTION? USEC_STORE_FUNCTION(cfq_slice_idle_us_store, &cfqd->cfq_slice_idle, 0, UINT_MAX); ^~~~~~~~~~~~~~~~~~~ block/cfq-iosched.c: In function ?cfq_group_idle_us_store?: block/cfq-iosched.c:4775:13: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits] if (__data < (MIN)) \ ^ block/cfq-iosched.c:4783:1: note: in expansion of macro ?USEC_STORE_FUNCTION? USEC_STORE_FUNCTION(cfq_group_idle_us_store, &cfqd->cfq_group_idle, 0, UINT_MAX); ^~~~~~~~~~~~~~~~~~~ Signed-off-by: Bart Van Assche Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

blk-mq: count the hctx as active before allocating tag

2018-09-15T07:46:52Z

[ Upstream commit d263ed9926823c462f99a7679e18f0c9e5b8550d ] Currently, we count the hctx as active after allocate driver tag successfully. If a previously inactive hctx try to get tag first time, it may fails and need to wait. However, due to the stale tag ->active_queues, the other shared-tags users are still able to occupy all driver tags while there is someone waiting for tag. Consequently, even if the previously inactive hctx is waked up, it still may not be able to get a tag and could be starved. To fix it, we count the hctx as active before try to allocate driver tag, then when it is waiting the tag, the other shared-tag users will reserve budget for it. Reviewed-by: Ming Lei Signed-off-by: Jianchao Wang Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman