BMC/Intel-BMC/linux.git/block/blk-core.c, branch dev-4.17

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

2018-08-09T10:15:12+00:00

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

2018-07-22T13:16:06+00:00

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

block: Fix cloning of requests with a special payload

2018-07-03T09:27:11+00:00

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

blk-mq: start request gstate with gen 1

2018-04-17T03:56:41+00:00

rq->gstate and rq->aborted_gstate both are zero before rqs are allocated. If we have a small timeout, when the timer fires, there could be rqs that are never allocated, and also there could be rq that has been allocated but not initialized and started. At the moment, the rq->gstate and rq->aborted_gstate both are 0, thus the blk_mq_terminate_expired will identify the rq is timed out and invoke .timeout early. For scsi, this will cause scsi_times_out to be invoked before the scsi_cmnd is not initialized, scsi_cmnd->device is still NULL at the moment, then we will get crash. Cc: Bart Van Assche Cc: Tejun Heo Cc: Ming Lei Cc: Martin Steigerwald Cc: stable@vger.kernel.org Signed-off-by: Jianchao Wang Signed-off-by: Jens Axboe

block: do not use interruptible wait anywhere

2018-04-14T19:54:33+00:00

When blk_queue_enter() waits for a queue to unfreeze, or unset the PREEMPT_ONLY flag, do not allow it to be interrupted by a signal. The PREEMPT_ONLY flag was introduced later in commit 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably"). Note the SCSI device is resumed asynchronously, i.e. after un-freezing userspace tasks. So that commit exposed the bug as a regression in v4.15. A mysterious SIGBUS (or -EIO) sometimes happened during the time the device was being resumed. Most frequently, there was no kernel log message, and we saw Xorg or Xwayland killed by SIGBUS.[1] [1] E.g. https://bugzilla.redhat.com/show_bug.cgi?id=1553979 Without this fix, I get an IO error in this test: # dd if=/dev/sda of=/dev/null iflag=direct & \ while killall -SIGUSR1 dd; do sleep 0.1; done & \ echo mem > /sys/power/state ; \ sleep 5; killall dd # stop after 5 seconds The interruptible wait was added to blk_queue_enter in commit 3ef28e83ab15 ("block: generic request_queue reference counting"). Before then, the interruptible wait was only in blk-mq, but I don't think it could ever have been correct. Reviewed-by: Bart Van Assche Cc: stable@vger.kernel.org Signed-off-by: Alan Jenkins Signed-off-by: Jens Axboe

blk-mq: Avoid that submitting a bio concurrently with device removal triggers a crash

2018-04-10T23:46:40+00:00

Because blkcg_exit_queue() is now called from inside blk_cleanup_queue() it is no longer safe to access cgroup information during or after the blk_cleanup_queue() call. Hence protect the generic_make_request_checks() call with blk_queue_enter() / blk_queue_exit(). Reported-by: Ming Lei Fixes: a063057d7c73 ("block: Fix a race between request queue removal and the block cgroup controller") Signed-off-by: Bart Van Assche Cc: Ming Lei Cc: Joseph Qi Signed-off-by: Jens Axboe

Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block

2018-04-05T21:27:02+00:00

Pull block layer updates from Jens Axboe: "It's a pretty quiet round this time, which is nice. This contains: - series from Bart, cleaning up the way we set/test/clear atomic queue flags. - series from Bart, fixing races between gendisk and queue registration and removal. - set of bcache fixes and improvements from various folks, by way of Michael Lyle. - set of lightnvm updates from Matias, most of it being the 1.2 to 2.0 transition. - removal of unused DIO flags from Nikolay. - blk-mq/sbitmap memory ordering fixes from Omar. - divide-by-zero fix for BFQ from Paolo. - minor documentation patches from Randy. - timeout fix from Tejun. - Alpha "can't write a char atomically" fix from Mikulas. - set of NVMe fixes by way of Keith. - bsg and bsg-lib improvements from Christoph. - a few sed-opal fixes from Jonas. - cdrom check-disk-change deadlock fix from Maurizio. - various little fixes, comment fixes, etc from various folks" * tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits) blk-mq: Directly schedule q->timeout_work when aborting a request blktrace: fix comment in blktrace_api.h lightnvm: remove function name in strings lightnvm: pblk: remove some unnecessary NULL checks lightnvm: pblk: don't recover unwritten lines lightnvm: pblk: implement 2.0 support lightnvm: pblk: implement get log report chunk lightnvm: pblk: rename ppaf* to addrf* lightnvm: pblk: check for supported version lightnvm: implement get log report chunk helpers lightnvm: make address conversions depend on generic device lightnvm: add support for 2.0 address format lightnvm: normalize geometry nomenclature lightnvm: complete geo structure with maxoc* lightnvm: add shorten OCSSD version in geo lightnvm: add minor version to generic geometry lightnvm: simplify geometry structure lightnvm: pblk: refactor init/exit sequences lightnvm: Avoid validation of default op value lightnvm: centralize permission check for lightnvm ioctl ...

block: Change a rcu_read_{lock,unlock}_sched() pair into rcu_read_{lock,unlock}()

2018-03-19T18:50:10+00:00

scsi_device_quiesce() uses synchronize_rcu() to guarantee that the effect of blk_set_preempt_only() will be visible for percpu_ref_tryget() calls that occur after the queue unfreeze by using the approach explained in https://lwn.net/Articles/573497/. The rcu read lock and unlock calls in blk_queue_enter() form a pair with the synchronize_rcu() call in scsi_device_quiesce(). Both scsi_device_quiesce() and blk_queue_enter() must either use regular RCU or RCU-sched. Since neither the RCU-protected code in blk_queue_enter() nor blk_queue_usage_counter_release() sleeps, regular RCU protection is sufficient. Note: scsi_device_quiesce() does not have to be modified since it already uses synchronize_rcu(). Reported-by: Tejun Heo Fixes: 3a0a529971ec ("block, scsi: Make SCSI quiesce and resume work reliably") Signed-off-by: Bart Van Assche Acked-by: Tejun Heo Cc: Tejun Heo Cc: Hannes Reinecke Cc: Ming Lei Cc: Christoph Hellwig Cc: Johannes Thumshirn Cc: Oleksandr Natalenko Cc: Martin Steigerwald Cc: stable@vger.kernel.org # v4.15 Signed-off-by: Jens Axboe

block: bio_check_eod() needs to consider partitions

2018-03-17T20:48:04+00:00

bio_check_eod() should check partition size not the whole disk if bio->bi_partno is non-zero. Do this by moving the call to bio_check_eod() into blk_partition_remap(). Based on an earlier patch from Jiufei Xue. Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") Reported-by: Jiufei Xue Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

block: Introduce blk_queue_flag_{set,clear,test_and_{set,clear}}()

2018-03-08T21:13:48+00:00

Introduce functions that modify the queue flags and that protect these modifications with the request queue lock. Except for moving one wake_up_all() call from inside to outside a critical section, this patch does not change any functionality. Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Ming Lei Reviewed-by: Johannes Thumshirn Reviewed-by: Martin K. Petersen Signed-off-by: Bart Van Assche Signed-off-by: Jens Axboe