- 25 Oct, 2021 4 commits
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Jens Axboe authored
KCSAN complaints about the sbitmap hint update: ================================================================== BUG: KCSAN: data-race in sbitmap_queue_clear / sbitmap_queue_clear write to 0xffffe8ffffd145b8 of 4 bytes by interrupt on cpu 1: sbitmap_queue_clear+0xca/0xf0 lib/sbitmap.c:606 blk_mq_put_tag+0x82/0x90 __blk_mq_free_request+0x114/0x180 block/blk-mq.c:507 blk_mq_free_request+0x2c8/0x340 block/blk-mq.c:541 __blk_mq_end_request+0x214/0x230 block/blk-mq.c:565 blk_mq_end_request+0x37/0x50 block/blk-mq.c:574 lo_complete_rq+0xca/0x170 drivers/block/loop.c:541 blk_complete_reqs block/blk-mq.c:584 [inline] blk_done_softirq+0x69/0x90 block/blk-mq.c:589 __do_softirq+0x12c/0x26e kernel/softirq.c:558 run_ksoftirqd+0x13/0x20 kernel/softirq.c:920 smpboot_thread_fn+0x22f/0x330 kernel/smpboot.c:164 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 write to 0xffffe8ffffd145b8 of 4 bytes by interrupt on cpu 0: sbitmap_queue_clear+0xca/0xf0 lib/sbitmap.c:606 blk_mq_put_tag+0x82/0x90 __blk_mq_free_request+0x114/0x180 block/blk-mq.c:507 blk_mq_free_request+0x2c8/0x340 block/blk-mq.c:541 __blk_mq_end_request+0x214/0x230 block/blk-mq.c:565 blk_mq_end_request+0x37/0x50 block/blk-mq.c:574 lo_complete_rq+0xca/0x170 drivers/block/loop.c:541 blk_complete_reqs block/blk-mq.c:584 [inline] blk_done_softirq+0x69/0x90 block/blk-mq.c:589 __do_softirq+0x12c/0x26e kernel/softirq.c:558 run_ksoftirqd+0x13/0x20 kernel/softirq.c:920 smpboot_thread_fn+0x22f/0x330 kernel/smpboot.c:164 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 value changed: 0x00000035 -> 0x00000044 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10 Comm: ksoftirqd/0 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ================================================================== which is a data race, but not an important one. This is just updating the percpu alloc hint, and the reader of that hint doesn't ever require it to be valid. Just annotate it with data_race() to silence this one. Reported-by: syzbot+4f8bfd804b4a1f95b8f6@syzkaller.appspotmail.com Acked-by:
Marco Elver <elver@google.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk>
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Yu Kuai authored
Our test reports a null pointer dereference: [ 168.534653] ================================================================== [ 168.535614] Disabling lock debugging due to kernel taint [ 168.536346] BUG: kernel NULL pointer dereference, address: 0000000000000008 [ 168.537274] #PF: supervisor read access in kernel mode [ 168.537964] #PF: error_code(0x0000) - not-present page [ 168.538667] PGD 0 P4D 0 [ 168.539025] Oops: 0000 [#1] PREEMPT SMP KASAN [ 168.539656] CPU: 13 PID: 759 Comm: bash Tainted: G B 5.15.0-rc2-next-202100 [ 168.540954] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_0738364 [ 168.542736] RIP: 0010:bfq_pd_init+0x88/0x1e0 [ 168.543318] Code: 98 00 00 00 e8 c9 e4 5b ff 4c 8b 65 00 49 8d 7c 24 08 e8 bb e4 5b ff 4d0 [ 168.545803] RSP: 0018:ffff88817095f9c0 EFLAGS: 00010002 [ 168.546497] RAX: 0000000000000001 RBX: ffff888101a1c000 RCX: 0000000000000000 [ 168.547438] RDX: 0000000000000003 RSI: 0000000000000002 RDI: ffff888106553428 [ 168.548402] RBP: ffff888106553400 R08: ffffffff961bcaf4 R09: 0000000000000001 [ 168.549365] R10: ffffffffa2e16c27 R11: fffffbfff45c2d84 R12: 0000000000000000 [ 168.550291] R13: ffff888101a1c098 R14: ffff88810c7a08c8 R15: ffffffffa55541a0 [ 168.551221] FS: 00007fac75227700(0000) GS:ffff88839ba80000(0000) knlGS:0000000000000000 [ 168.552278] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 168.553040] CR2: 0000000000000008 CR3: 0000000165ce7000 CR4: 00000000000006e0 [ 168.554000] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 168.554929] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 168.555888] Call Trace: [ 168.556221] <TASK> [ 168.556510] blkg_create+0x1c0/0x8c0 [ 168.556989] blkg_conf_prep+0x574/0x650 [ 168.557502] ? stack_trace_save+0x99/0xd0 [ 168.558033] ? blkcg_conf_open_bdev+0x1b0/0x1b0 [ 168.558629] tg_set_conf.constprop.0+0xb9/0x280 [ 168.559231] ? kasan_set_track+0x29/0x40 [ 168.559758] ? kasan_set_free_info+0x30/0x60 [ 168.560344] ? tg_set_limit+0xae0/0xae0 [ 168.560853] ? do_sys_openat2+0x33b/0x640 [ 168.561383] ? do_sys_open+0xa2/0x100 [ 168.561877] ? __x64_sys_open+0x4e/0x60 [ 168.562383] ? __kasan_check_write+0x20/0x30 [ 168.562951] ? copyin+0x48/0x70 [ 168.563390] ? _copy_from_iter+0x234/0x9e0 [ 168.563948] tg_set_conf_u64+0x17/0x20 [ 168.564467] cgroup_file_write+0x1ad/0x380 [ 168.565014] ? cgroup_file_poll+0x80/0x80 [ 168.565568] ? __mutex_lock_slowpath+0x30/0x30 [ 168.566165] ? pgd_free+0x100/0x160 [ 168.566649] kernfs_fop_write_iter+0x21d/0x340 [ 168.567246] ? cgroup_file_poll+0x80/0x80 [ 168.567796] new_sync_write+0x29f/0x3c0 [ 168.568314] ? new_sync_read+0x410/0x410 [ 168.568840] ? __handle_mm_fault+0x1c97/0x2d80 [ 168.569425] ? copy_page_range+0x2b10/0x2b10 [ 168.570007] ? _raw_read_lock_bh+0xa0/0xa0 [ 168.570622] vfs_write+0x46e/0x630 [ 168.571091] ksys_write+0xcd/0x1e0 [ 168.571563] ? __x64_sys_read+0x60/0x60 [ 168.572081] ? __kasan_check_write+0x20/0x30 [ 168.572659] ? do_user_addr_fault+0x446/0xff0 [ 168.573264] __x64_sys_write+0x46/0x60 [ 168.573774] do_syscall_64+0x35/0x80 [ 168.574264] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 168.574960] RIP: 0033:0x7fac74915130 [ 168.575456] Code: 73 01 c3 48 8b 0d 58 ed 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 444 [ 168.577969] RSP: 002b:00007ffc3080e288 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 168.578986] RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007fac74915130 [ 168.579937] RDX: 0000000000000009 RSI: 000056007669f080 RDI: 0000000000000001 [ 168.580884] RBP: 000056007669f080 R08: 000000000000000a R09: 00007fac75227700 [ 168.581841] R10: 000056007655c8f0 R11: 0000000000000246 R12: 0000000000000009 [ 168.582796] R13: 0000000000000001 R14: 00007fac74be55e0 R15: 00007fac74be08c0 [ 168.583757] </TASK> [ 168.584063] Modules linked in: [ 168.584494] CR2: 0000000000000008 [ 168.584964] ---[ end trace 2475611ad0f77a1a ]--- This is because blkg_alloc() is called from blkg_conf_prep() without holding 'q->queue_lock', and elevator is exited before blkg_create(): thread 1 thread 2 blkg_conf_prep spin_lock_irq(&q->queue_lock); blkg_lookup_check -> return NULL spin_unlock_irq(&q->queue_lock); blkg_alloc blkcg_policy_enabled -> true pd = ->pd_alloc_fn blkg->pd[i] = pd blk_mq_exit_sched bfq_exit_queue blkcg_deactivate_policy spin_lock_irq(&q->queue_lock); __clear_bit(pol->plid, q->blkcg_pols); spin_unlock_irq(&q->queue_lock); q->elevator = NULL; spin_lock_irq(&q->queue_lock); blkg_create if (blkg->pd[i]) ->pd_init_fn -> q->elevator is NULL spin_unlock_irq(&q->queue_lock); Because blkcg_deactivate_policy() requires queue to be frozen, we can grab q_usage_counter to synchoronize blkg_conf_prep() against blkcg_deactivate_policy(). Fixes: e21b7a0b ("block, bfq: add full hierarchical scheduling and cgroups support") Signed-off-by:Yu Kuai <yukuai3@huawei.com> Acked-by:
Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20211020014036.2141723-1-yukuai3@huawei.comSigned-off-by:
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Pavel Begunkov authored
Combine bio_iov_bvec_set() and bio_iov_bvec_set_append() and let the caller to do iov_iter_advance(). Also get rid of __bio_iov_bvec_set(), which was duplicated in the final binary, and replace a weird iov_iter_truncate() of a temporal iter copy with min() better reflecting the intention. Signed-off-by:
Pavel Begunkov <asml.silence@gmail.com> Reviewed-by:
Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/bcf1ac36fce769a514e19475f3623cd86a1d8b72.1635006010.git.asml.silence@gmail.comSigned-off-by:
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Pavel Begunkov authored
As with __blkdev_direct_IO_simple(), we can implement direct IO more efficiently if there is only one bio. Add __blkdev_direct_IO_async() and blkdev_bio_end_io_async(). This patch brings me from 4.45-4.5 MIOPS with nullblk to 4.7+. Signed-off-by:
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- 23 Oct, 2021 1 commit
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Jens Axboe authored
If CONFIG_BLOCK isn't set, then it's an empty struct anyway. Just make it generally available, so we don't break the compile: kernel/sched/core.c: In function ‘sched_submit_work’: kernel/sched/core.c:6346:35: error: ‘struct task_struct’ has no member named ‘plug’ 6346 | blk_flush_plug(tsk->plug, true); | ^~ kernel/sched/core.c: In function ‘io_schedule_prepare’: kernel/sched/core.c:8357:20: error: ‘struct task_struct’ has no member named ‘plug’ 8357 | if (current->plug) | ^~ kernel/sched/core.c:8358:39: error: ‘struct task_struct’ has no member named ‘plug’ 8358 | blk_flush_plug(current->plug, true); | ^~ Reported-by:Nathan Chancellor <nathan@kernel.org> Fixes: 008f75a2 ("block: cleanup the flush plug helpers") Signed-off-by:
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- 22 Oct, 2021 2 commits
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John Garry authored
We should not reference the queue tagset in blk_mq_sched_tags_teardown() (see function comment) for the blk-mq flags, so use the passed flags instead. This solves a use-after-free, similarly fixed earlier (and since broken again) in commit f0c1c4d2 ("blk-mq: fix use-after-free in blk_mq_exit_sched"). Reported-by:
Linux Kernel Functional Testing <lkft@linaro.org> Reported-by:
Naresh Kamboju <naresh.kamboju@linaro.org> Tested-by:
Anders Roxell <anders.roxell@linaro.org> Fixes: e155b0c2 ("blk-mq: Use shared tags for shared sbitmap support") Signed-off-by:
John Garry <john.garry@huawei.com> Link: https://lore.kernel.org/r/1634890340-15432-1-git-send-email-john.garry@huawei.comSigned-off-by:
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Pavel Begunkov authored
Shinichiro Kawasaki reports that there is a bug in a recent req_bio_endio() patch causing problems with zonefs. As Shinichiro suggested, inverse the condition in zone append path to resemble how it was before: fail when it's not fully completed. Fixes: 478eb72b ("block: optimise req_bio_endio()") Reported-by:
Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com> Signed-off-by:
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- 21 Oct, 2021 15 commits
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Eric Biggers authored
Rework most of inline-encryption.rst to be easier to follow, to correct some information, to add some important details and remove some unimportant details, and to take into account the renaming from blk_keyslot_manager to blk_crypto_profile. Reviewed-by:
Mike Snitzer <snitzer@redhat.com> Reviewed-by:
Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by:
Eric Biggers <ebiggers@google.com> Link: https://lore.kernel.org/r/20211018180453.40441-5-ebiggers@kernel.orgSigned-off-by:
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Eric Biggers authored
blk_keyslot_manager is misnamed because it doesn't necessarily manage keyslots. It actually does several different things: - Contains the crypto capabilities of the device. - Provides functions to control the inline encryption hardware. Originally these were just for programming/evicting keyslots; however, new functionality (hardware-wrapped keys) will require new functions here which are unrelated to keyslots. Moreover, device-mapper devices already (ab)use "keyslot_evict" to pass key eviction requests to their underlying devices even though device-mapper devices don't have any keyslots themselves (so it really should be "evict_key", not "keyslot_evict"). - Sometimes (but not always!) it manages keyslots. Originally it always did, but device-mapper devices don't have keyslots themselves, so they use a "passthrough keyslot manager" which doesn't actually manage keyslots. This hack works, but the terminology is unnatural. Also, some hardware doesn't have keyslots and thus also uses a "passthrough keyslot manager" (support for such hardware is yet to be upstreamed, but it will happen eventually). Let's stop having keyslot managers which don't actually manage keyslots. Instead, rename blk_keyslot_manager to blk_crypto_profile. This is a fairly big change, since for consistency it also has to update keyslot manager-related function names, variable names, and comments -- not just the actual struct name. However it's still a fairly straightforward change, as it doesn't change any actual functionality. Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Reviewed-by: -
Eric Biggers authored
In preparation for renaming struct blk_keyslot_manager to struct blk_crypto_profile, rename the keyslot-manager.h and keyslot-manager.c source files. Renaming these files separately before making a lot of changes to their contents makes it easier for git to understand that they were renamed. Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # For MMC Reviewed-by:
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Eric Biggers authored
For clarity, avoid using just the "blk_crypto_" prefix for functions and structs that are specific to blk-crypto-fallback. Instead, use "blk_crypto_fallback_". Some places already did this, but others didn't. This is also a prerequisite for using "struct blk_crypto_keyslot" to mean a generic blk-crypto keyslot (which is what it sounds like). Rename the fallback one to "struct blk_crypto_fallback_keyslot". No change in behavior. Reviewed-by:
Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by:
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Xie Yongji authored
When a nbd device encounters a writeback error, that error will get propagated to the bd_inode's wb_err field. Then if this nbd device's backend is disconnected and another is attached, we will get back the previous writeback error on fsync, which is unexpected. To fix it, let's use invalidate_disk() helper to invalidate the disk on disconnect instead of just setting disk's capacity to zero. Signed-off-by:
Xie Yongji <xieyongji@bytedance.com> Reviewed-by:
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Xie Yongji authored
The lo->lo_device can't be null if the lo->lo_backing_file is set. So let's remove the unnecessary bdev checks and the entire bdev variable in __loop_clr_fd() since the lo->lo_backing_file is already checked before. Signed-off-by:
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Xie Yongji authored
Use invalidate_disk() helper to simplify the code for gendisk invalidation. Signed-off-by:
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Xie Yongji authored
To hide internal implementation and simplify some driver code, this adds a helper to invalidate the gendisk. It will clean the gendisk's associated buffer/page caches and reset its internal states. Signed-off-by:
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Pavel Begunkov authored
blk_try_enter_queue() already takes rcu_read_lock/unlock, so we can avoid the second pair in percpu_ref_tryget_live(), use a newly added percpu_ref_tryget_live_rcu(). As rcu_read_lock/unlock imply barrier()s, it's pretty noticeable, especially for for !CONFIG_PREEMPT_RCU (default for some distributions), where __rcu_read_lock/unlock() are not inlined. 3.20% io_uring [kernel.vmlinux] [k] __rcu_read_unlock 3.05% io_uring [kernel.vmlinux] [k] __rcu_read_lock 2.52% io_uring [kernel.vmlinux] [k] __rcu_read_unlock 2.28% io_uring [kernel.vmlinux] [k] __rcu_read_lock Signed-off-by:
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Pavel Begunkov authored
Add percpu_ref_tryget_live_rcu(), which is a version of percpu_ref_tryget_live() but the user is responsible for enclosing it in a RCU read lock section. Signed-off-by:
Dennis Zhou <dennis@kernel.org> Link: https://lore.kernel.org/r/3066500d7a6eb3e03f10adf98b87fdb3b1c49db8.1634822969.git.asml.silence@gmail.comSigned-off-by:
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Pavel Begunkov authored
Don't use shifting by a magic number 9 but replace with a more descriptive SHIFT_SECTOR. Signed-off-by:
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Pavel Begunkov authored
Combine blk_mq_sched_bio_merge() and blk_attempt_plug_merge() under a common if, so we don't check it twice. Signed-off-by:
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Pavel Begunkov authored
Combine pos and len checks and mark unlikely. Also, don't reexpand if it's not truncated. Reviewed-by:
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Jackie Liu authored
We switched to directly use dev_t to get block device, lookup changed the meaning of use, now we fix this conflicting comment. Fixes: 4e7b5671 ("block: remove i_bdev") Cc: Jens Axboe <axboe@kernel.dk> Cc: Christoph Hellwig <hch@lst.de> Cc: linux-fsdevel@vger.kernel.org Signed-off-by:
Jackie Liu <liuyun01@kylinos.cn> Reviewed-by:
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John Garry authored
Since it is now possible for a tagset to share a single set of tags, the iter function should not re-iter the tags for the count of #hw queues in that case. Rather it should just iter once. Fixes: e155b0c2 ("blk-mq: Use shared tags for shared sbitmap support") Reported-by:
Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by:
Ming Lei <ming.lei@redhat.com> Tested-by:
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- 20 Oct, 2021 16 commits
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Christoph Hellwig authored
Consolidate the various helpers into a single blk_flush_plug helper that takes a plk_plug and the from_scheduler bool and switch all callsites to call it directly. Checks that the plug is non-NULL must be performed by the caller, something that most already do anyway. Signed-off-by:
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Pavel Begunkov authored
Don't call flush_plug_callbacks if there are no plug callbacks. Signed-off-by:
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Christoph Hellwig authored
This helper is internal to the block layer. Signed-off-by:
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Christoph Hellwig authored
Replace the call to blk_flush_plug_list in blk_mq_submit_bio with a direct call to blk_mq_flush_plug_list. This means we do not flush plug callback from stackable devices, which doesn't really help with the accumulated requests anyway, and it also means the cached requests aren't freed here as they can still be used later on. Signed-off-by:
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Jens Axboe authored
This check is meant to catch cases where a requeue is attempted on a request that is still inserted. It's never really been useful to catch any misuse, and now it's actively wrong. Outside of that, this should not be a BUG_ON() to begin with. Remove the check as it's now causing active harm, as requeue off the plug path will trigger it even though the request state is just fine. Reported-by:
Yi Zhang <yi.zhang@redhat.com> Link: https://lore.kernel.org/linux-block/CAHj4cs80zAUc2grnCZ015-2Rvd-=gXRfB_dFKy=RTm+wRo09HQ@mail.gmail.com/Signed-off-by:
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Pavel Begunkov authored
Inline BIO_NO_PAGE_REF check of bio_release_pages() to avoid function call. Signed-off-by:
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Pavel Begunkov authored
percpu_ref_put() are inlined for performance and bloat the binary, we don't care about the fail case of blk_try_enter_queue(), so we can replace it with a call to blk_queue_exit(). Reviewed-by:
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Pavel Begunkov authored
First, get rid of an extra branch and chain error checks. Also reshuffle it with bio_advance(), so it goes closer to the final check, with that the compiler loads rq->rq_flags only once, and also doesn't reload bio->bi_iter.bi_size if bio_advance() didn't actually advanced the iter. Reviewed-by:
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Pavel Begunkov authored
Convert bdev->bd_disk->queue to bdev_get_queue(), which is faster. Apparently, there are a few such spots in block that got lost during rebases. Reviewed-by:
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Pavel Begunkov authored
Replace bio_set_dev() with an identical inline helper and move it further to fix a dependency problem with bio_associate_blkg(). Do the same for bio_copy_dev(). Reviewed-by:
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Ming Lei authored
blk_mq_quiesce_queue() has been used a bit wide now, so far we don't support concurrent/nested quiesce. One biggest issue is that unquiesce can happen unexpectedly in case that quiesce/unquiesce are run concurrently from more than one context. This patch introduces q->mq_quiesce_depth to deal concurrent quiesce, and we only unquiesce queue when it is the last/outer-most one of all contexts. Several kernel panic issue has been reported[1][2][3] when running stress quiesce test. And this patch has been verified in these reports. [1] https://lore.kernel.org/linux-block/9b21c797-e505-3821-4f5b-df7bf9380328@huawei.com/T/#m1fc52431fad7f33b1ffc3f12c4450e4238540787 [2] https://lore.kernel.org/linux-block/9b21c797-e505-3821-4f5b-df7bf9380328@huawei.com/T/#m10ad90afeb9c8cc318334190a7c24c8b5c5e0722 [3] https://listman.redhat.com/archives/dm-devel/2021-September/msg00189.htmlSigned-off-by:
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Ming Lei authored
The nvme-loop's admin queue may be freed and reallocated, and we have to reset the flag of NVME_CTRL_ADMIN_Q_STOPPED so that the flag can match with the quiesce state of the admin queue. nvme-loop is the only driver to reallocate request queue, and not see such usage in other nvme drivers. Signed-off-by:
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Ming Lei authored
The current blk_mq_quiesce_queue() and blk_mq_unquiesce_queue() always stops and starts the queue unconditionally. And there can be concurrent quiesce/unquiesce coming from different unrelated code paths, so unquiesce may come unexpectedly and start queue too early. Prepare for supporting concurrent quiesce/unquiesce from multiple contexts, so that we can address the above issue. NVMe has very complicated quiesce/unquiesce use pattern, add one atomic bit for makeiing sure that blk-mq quiece/unquiesce is always called in pair. Signed-off-by:
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Ming Lei authored
Add two helpers so that we can prepare for pairing quiescing and unquiescing which will be done in next patch. Signed-off-by:
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Ming Lei authored
Apply the added two APIs to quiesce/unquiesce admin queue. Signed-off-by:
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Ming Lei authored
Add two APIs for stopping and starting admin queue. Signed-off-by:
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- 19 Oct, 2021 2 commits
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Zheng Liang authored
In bfq_pd_alloc(), the function bfqg_stats_init() init bfqg. If blkg_rwstat_init() init bfqg_stats->bytes successful and init bfqg_stats->ios failed, bfqg_stats_init() return failed, bfqg will be freed. But blkg_rwstat->cpu_cnt is not deleted from the list of percpu_counters. If we traverse the list of percpu_counters, It will have UAF problem. we should use blkg_rwstat_exit() to cleanup bfqg_stats bytes in the above scenario. Fixes: commit fd41e603 ("bfq-iosched: stop using blkg->stat_bytes and ->stat_ios") Signed-off-by:
Zheng Liang <zhengliang6@huawei.com> Acked-by:
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Jens Axboe authored
If we don't use an IO scheduler or have shared tags, then we don't need to call into this external function at all. This saves ~2% for such a setup. Signed-off-by:
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