kernel/block, branch linux-4.17.y

blk-mq: don't queue more if we get a busy return

2018-08-24T11:06:54Z

[ Upstream commit 1f57f8d442f8017587eeebd8617913bfc3661d3d ] Some devices have different queue limits depending on the type of IO. A classic case is SATA NCQ, where some commands can queue, but others cannot. If we have NCQ commands inflight and encounter a non-queueable command, the driver returns busy. Currently we attempt to dispatch more from the scheduler, if we were able to queue some commands. But for the case where we ended up stopping due to BUSY, we should not attempt to retrieve more from the scheduler. If we do, we can get into a situation where we attempt to queue a non-queueable command, get BUSY, then successfully retrieve more commands from that scheduler and queue those. This can repeat forever, starving the non-queuable command indefinitely. Fix this by NOT attempting to pull more commands from the scheduler, if we get a BUSY return. This should also be more optimal in terms of letting requests stay in the scheduler for as long as possible, if we get a BUSY due to the regular out-of-tags condition. Reviewed-by: Omar Sandoval Reviewed-by: Ming Lei Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

block: sed-opal: Fix a couple off by one bugs

2018-08-24T11:06:45Z

[ Upstream commit ce042c183bcb94eb2919e8036473a1fc203420f9 ] resp->num is the number of tokens in resp->tok[]. It gets set in response_parse(). So if n == resp->num then we're reading beyond the end of the data. Fixes: 455a7b238cd6 ("block: Add Sed-opal library") Reviewed-by: Scott Bauer Tested-by: Scott Bauer Signed-off-by: Dan Carpenter Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

blk-mq-debugfs: Off by one in blk_mq_rq_state_name()

2018-08-24T11:06:45Z

[ Upstream commit a1e79188628580465ac6d7a93a313336ee3364f1 ] If rq_state == ARRAY_SIZE() then we read one element beyond the end of the blk_mq_rq_state_name_array[] array. Fixes: ec6dcf63c55c ("blk-mq-debugfs: Show more request state information") Reviewed-by: Bart Van Assche Signed-off-by: Dan Carpenter Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

Partially revert "block: fail op_is_write() requests to read-only partitions"

2018-08-09T10:15:12Z

commit a32e236eb93e62a0f692e79b7c3c9636689559b9 upstream. It turns out that commit 721c7fc701c7 ("block: fail op_is_write() requests to read-only partitions"), while obviously correct, causes problems for some older lvm2 installations. The reason is that the lvm snapshotting will continue to write to the snapshow COW volume, even after the volume has been marked read-only. End result: snapshot failure. This has actually been fixed in newer version of the lvm2 tool, but the old tools still exist, and the breakage was reported both in the kernel bugzilla and in the Debian bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200439 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=900442 The lvm2 fix is here https://sourceware.org/git/?p=lvm2.git;a=commit;h=a6fdb9d9d70f51c49ad11a87ab4243344e6701a3 but until everybody has updated to recent versions, we'll have to weaken the "never write to read-only partitions" check. It now allows the write to happen, but causes a warning, something like this: generic_make_request: Trying to write to read-only block-device dm-3 (partno X) Modules linked in: nf_tables xt_cgroup xt_owner kvm_intel iwlmvm kvm irqbypass iwlwifi CPU: 1 PID: 77 Comm: kworker/1:1 Not tainted 4.17.9-gentoo #3 Hardware name: LENOVO 20B6A019RT/20B6A019RT, BIOS GJET91WW (2.41 ) 09/21/2016 Workqueue: ksnaphd do_metadata RIP: 0010:generic_make_request_checks+0x4ac/0x600 ... Call Trace: generic_make_request+0x64/0x400 submit_bio+0x6c/0x140 dispatch_io+0x287/0x430 sync_io+0xc3/0x120 dm_io+0x1f8/0x220 do_metadata+0x1d/0x30 process_one_work+0x1b9/0x3e0 worker_thread+0x2b/0x3c0 kthread+0x113/0x130 ret_from_fork+0x35/0x40 Note that this is a "revert" in behavior only. I'm leaving alone the actual code cleanups in commit 721c7fc701c7, but letting the previously uncaught request go through with a warning instead of stopping it. Fixes: 721c7fc701c7 ("block: fail op_is_write() requests to read-only partitions") Reported-and-tested-by: WGH Acked-by: Mike Snitzer Cc: Sagi Grimberg Cc: Ilya Dryomov Cc: Jens Axboe Cc: Zdenek Kabelac Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

block: reset bi_iter.bi_done after splitting bio

2018-08-03T05:48:02Z

commit 5151842b9d8732d4cbfa8400b40bff894f501b2f upstream. After the bio has been updated to represent the remaining sectors, reset bi_done so bio_rewind_iter() does not rewind further than it should. This resolves a bio_integrity_process() failure on reads where the original request was split. Fixes: 63573e359d05 ("bio-integrity: Restore original iterator on verify stage") Signed-off-by: Greg Edwards Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block: bio_iov_iter_get_pages: fix size of last iovec

2018-08-03T05:48:02Z

commit b403ea2404889e1227812fa9657667a1deb9c694 upstream. If the last page of the bio is not "full", the length of the last vector slot needs to be corrected. This slot has the index (bio->bi_vcnt - 1), but only in bio->bi_io_vec. In the "bv" helper array, which is shifted by the value of bio->bi_vcnt at function invocation, the correct index is (nr_pages - 1). v2: improved readability following suggestions from Ming Lei. v3: followed a formatting suggestion from Christoph Hellwig. Fixes: 2cefe4dbaadf ("block: add bio_iov_iter_get_pages()") Reviewed-by: Hannes Reinecke Reviewed-by: Ming Lei Reviewed-by: Jan Kara Reviewed-by: Christoph Hellwig Signed-off-by: Martin Wilck Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block, bfq: remove wrong lock in bfq_requests_merged

2018-08-03T05:47:39Z

[ Upstream commit a12bffebc0c9d6a5851f062aaea3aa7c4adc6042 ] In bfq_requests_merged(), there is a deadlock because the lock on bfqq->bfqd->lock is held by the calling function, but the code of this function tries to grab the lock again. This deadlock is currently hidden by another bug (fixed by next commit for this source file), which causes the body of bfq_requests_merged() to be never executed. This commit removes the deadlock by removing the lock/unlock pair. Signed-off-by: Filippo Muzzini Signed-off-by: Paolo Valente Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

block: don't use blocking queue entered for recursive bio submits

2018-07-22T13:16:06Z

commit cd4a4ae4683dc2e09380118e205e057896dcda2b upstream. If we end up splitting a bio and the queue goes away between the initial submission and the later split submission, then we can block forever in blk_queue_enter() waiting for the reference to drop to zero. This will never happen, since we already hold a reference. Mark a split bio as already having entered the queue, so we can just use the live non-blocking queue enter variant. Thanks to Tetsuo Handa for the analysis. Reported-by: syzbot+c4f9cebf9d651f6e54de@syzkaller.appspotmail.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

bsg: fix bogus EINVAL on non-data commands

2018-07-17T09:48:32Z

commit 70dbcc2254fa2a9add74a122b9dac954c4736e01 upstream. Fix a regression introduced in Linux kernel 4.17 where sending a SCSI command that does not transfer data (such as TEST UNIT READY) via /dev/bsg/* results in EINVAL. Fixes: 17cb960f29c2 ("bsg: split handling of SCSI CDBs vs transport requeues") Cc: # 4.17+ Reviewed-by: Christoph Hellwig Signed-off-by: Tony Battersby Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

block: Fix cloning of requests with a special payload

2018-07-03T09:27:11Z

commit 297ba57dcdec7ea37e702bcf1a577ac32a034e21 upstream. This patch avoids that removing a path controlled by the dm-mpath driver while mkfs is running triggers the following kernel bug: kernel BUG at block/blk-core.c:3347! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 20 PID: 24369 Comm: mkfs.ext4 Not tainted 4.18.0-rc1-dbg+ #2 RIP: 0010:blk_end_request_all+0x68/0x70 Call Trace: dm_softirq_done+0x326/0x3d0 [dm_mod] blk_done_softirq+0x19b/0x1e0 __do_softirq+0x128/0x60d irq_exit+0x100/0x110 smp_call_function_single_interrupt+0x90/0x330 call_function_single_interrupt+0xf/0x20 Fixes: f9d03f96b988 ("block: improve handling of the magic discard payload") Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig Acked-by: Mike Snitzer Signed-off-by: Bart Van Assche Cc: Hannes Reinecke Cc: Johannes Thumshirn Cc: Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman