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Linux kernel
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disk_get_part needs to be paired with a disk_put_part.
Cc: stable@vger.kernel.org
Fixes: ef45fe470e1 ("blk-cgroup: show global disk stats in root cgroup io.stat")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For avoiding use-after-free on flush request, we call its .end_io() from
both timeout code path and __blk_mq_end_request().
When flush request's ref doesn't drop to zero, it is still used, we
can't mark it as IDLE, so fix it by marking IDLE when its refcount drops
to zero really.
Fixes: 65ff5cd04551 ("blk-mq: mark flush request as IDLE in flush_end_io()")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Cc: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 716ad0986cbd ("loop: Switch to set_capacity_revalidate_and_notify")
causes an occasional drop of loop device uevent, which are no longer
triggered in loop_set_size() but in a different part of code.
Bug is reproducible with LTP test uevent01 [1]:
i=0; while true; do
i=$((i+1)); echo "== $i =="
lsmod |grep -q loop && rmmod -f loop
./uevent01 || break
done
Put back triggering through code called in loop_set_size().
Fix required to add yet another parameter to
set_capacity_revalidate_and_notify().
[1] https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/uevents/uevent01.c
[hch: rebased on a different change to the prototype of
set_capacity_revalidate_and_notify]
Cc: stable@vger.kernel.org # v5.9
Fixes: 716ad0986cbd ("loop: Switch to set_capacity_revalidate_and_notify")
Reported-by: <ltp@lists.linux.it>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Return if the function ended up sending an uevent or not.
Cc: stable@vger.kernel.org # v5.9
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
bdget_disk needs to be paired with bdput to not leak a reference
on the block device inode.
Fixes: 08ba91ee6e2c ("nbd: Add the nbd NBD_DISCONNECT_ON_CLOSE config flag.")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull NVMe fix from Christoph:
"nvme fixes for 5.10:
- don't clear the read-only bit on a revalidate (Sagi Grimberg)"
* tag 'nvme-5.10-2020-11-10' of git://git.infradead.org/nvme:
nvme: fix incorrect behavior when BLKROSET is called by the user
Commit aa1c09cb65e2 ("null_blk: Fix locking in zoned mode") changed
zone locking to using the potentially sleeping wait_on_bit_io()
function. This is acceptable when memory backing is enabled as the
device queue is in that case marked as blocking, but this triggers a
scheduling while in atomic context with memory backing disabled.
Fix this by relying solely on the device zone spinlock for zone
information protection without temporarily releasing this lock around
null_process_cmd() execution in null_zone_write(). This is OK to do
since when memory backing is disabled, command processing does not
block and the memory backing lock nullb->lock is unused. This solution
avoids the overhead of having to mark a zoned null_blk device queue as
blocking when memory backing is unused.
This patch also adds comments to the zone locking code to explain the
unusual locking scheme.
Fixes: aa1c09cb65e2 ("null_blk: Fix locking in zoned mode")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The offending commit breaks BLKROSET ioctl because a device
revalidation will blindly override BLKROSET setting. Hence,
we remove the disk rw setting in case NVME_NS_ATTR_RO is cleared
from by the controller.
Fixes: 1293477f4f32 ("nvme: set gendisk read only based on nsattr")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull NVMe fixes from Christoph:
"nvme fixes for 5.10:
- revert a nvme_queue size optimization (Keith Bush)
- fabrics timeout races fixes (Chao Leng and Sagi Grimberg)"
* tag 'nvme-5.10-2020-11-05' of git://git.infradead.org/nvme:
nvme-tcp: avoid repeated request completion
nvme-rdma: avoid repeated request completion
nvme-tcp: avoid race between time out and tear down
nvme-rdma: avoid race between time out and tear down
nvme: introduce nvme_sync_io_queues
Revert "nvme-pci: remove last_sq_tail"
The request may be executed asynchronously, and rq->state may be
changed to IDLE. To avoid repeated request completion, only
MQ_RQ_COMPLETE of rq->state is checked in nvme_tcp_complete_timed_out.
It is not safe, so need adding check IDLE for rq->state.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull x86 fixes from Thomas Gleixner:
"Three fixes all related to #DB:
- Handle the BTF bit correctly so it doesn't get lost due to a kernel
#DB
- Only clear and set the virtual DR6 value used by ptrace on user
space triggered #DB. A kernel #DB must leave it alone to ensure
data consistency for ptrace.
- Make the bitmasking of the virtual DR6 storage correct so it does
not lose DR_STEP"
* tag 'x86-urgent-2020-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/debug: Fix DR_STEP vs ptrace_get_debugreg(6)
x86/debug: Only clear/set ->virtual_dr6 for userspace #DB
x86/debug: Fix BTF handling
The request may be executed asynchronously, and rq->state may be
changed to IDLE. To avoid repeated request completion, only
MQ_RQ_COMPLETE of rq->state is checked in nvme_rdma_complete_timed_out.
It is not safe, so need adding check IDLE for rq->state.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Chao Leng <lengchao@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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