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Fix a smatch report for the newly added nvme_auth_wq.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pul NVMe fixes from Christoph:
"nvme fixes for Linux 6.2
- fix a missing queue put in nvmet_fc_ls_create_association (Amit Engel)
- clear queue pointers on tag_set initialization failure
(Maurizio Lombardi)
- use workqueue dedicated to authentication (Shin'ichiro Kawasaki)"
* tag 'nvme-6.2-2023-02-02' of git://git.infradead.org/nvme:
nvme-auth: use workqueue dedicated to authentication
nvme: clear the request_queue pointers on failure in nvme_alloc_io_tag_set
nvme: clear the request_queue pointers on failure in nvme_alloc_admin_tag_set
nvme-fc: fix a missing queue put in nvmet_fc_ls_create_association
We source root cgroup stats from the system-wide stats, see blkcg_print_stat
and blkcg_rstat_flush, so don't update io state for root cgroup.
Fixes blkg leak issue introduced in commit 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()")
which starts to grab blkg's reference when adding iostat_cpu into percpu
blkcg list, but this state won't be consumed by blkcg_rstat_flush() where
the blkg reference is dropped.
Tested-by: Bart van Assche <bvanassche@acm.org>
Reported-by: Bart van Assche <bvanassche@acm.org>
Fixes: 3b8cc6298724 ("blk-cgroup: Optimize blkcg_rstat_flush()")
Cc: Tejun Heo <tj@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230202021804.278582-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
NVMe In-Band authentication uses two kinds of works: chap->auth_work and
ctrl->dhchap_auth_work. The latter work flushes or cancels the former
work. However, the both works are queued to the same workqueue nvme-wq.
It results in the lockdep WARNING as follows:
WARNING: possible recursive locking detected
6.2.0-rc4+ #1 Not tainted
--------------------------------------------
kworker/u16:7/69 is trying to acquire lock:
ffff902d52e65548 ((wq_completion)nvme-wq){+.+.}-{0:0}, at: start_flush_work+0x2c5/0x380
but task is already holding lock:
ffff902d52e65548 ((wq_completion)nvme-wq){+.+.}-{0:0}, at: process_one_work+0x210/0x410
To avoid the WARNING, introduce a new workqueue nvme-auth-wq dedicated
to chap->auth_work.
Reported-by: Daniel Wagner <dwagner@suse.de>
Link: https://lore.kernel.org/linux-nvme/20230130110802.paafkiipmitwtnwr@carbon.lan/
Fixes: f50fff73d620 ("nvme: implement In-Band authentication")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Tested-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit 2b3f056f72e5 moved a blk_put_queue() call from
blk_mq_destroy_queue() into its callers. Reflect this change in the
documentation block above blk_mq_destroy_queue().
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Chaitanya Kulkarni <kch@nvidia.com>
Cc: Keith Busch <kbusch@kernel.org>
Fixes: 2b3f056f72e5 ("blk-mq: move the call to blk_put_queue out of blk_mq_destroy_queue")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230130211233.831613-1-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In nvme_alloc_io_tag_set(), the connect_q pointer should be set to NULL
in case of error to avoid potential invalid pointer dereferences.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When validating drafted SPDK ublk target, in a case that
assigning large queue depth to multiqueue ublk device,
ublk target would run into a weird incorrect state. During
rounds of review and debug, An overflow bug was found
in ublk driver.
In ublk_cmd.h, UBLK_MAX_QUEUE_DEPTH is 4096 which means
each ublk queue depth can be set as large as 4096. But
when setting qd for a ublk device,
sizeof(struct ublk_queue) + depth * sizeof(struct ublk_io)
will be larger than 65535 if qd is larger than 2728.
Then queue_size is overflowed, and ublk_get_queue()
references a wrong pointer position. The wrong content of
ublk_queue elements will lead to out-of-bounds memory
access.
Extend queue_size in ublk_device as "unsigned int".
Signed-off-by: Liu Xiaodong <xiaodong.liu@intel.com>
Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20230131070552.115067-1-xiaodong.liu@intel.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If nvme_alloc_admin_tag_set() fails, the admin_q and fabrics_q pointers
are left with an invalid, non-NULL value. Other functions may then check
the pointers and dereference them, e.g. in
nvme_probe() -> out_disable: -> nvme_dev_remove_admin().
Fix the bug by setting admin_q and fabrics_q to NULL in case of error.
Also use the set variable to free the tag_set as ctrl->admin_tagset isn't
initialized yet.
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
After commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'"),
bic->bfqq will be accessed in bic_set_bfqq(), however, in some context
bic->bfqq will be freed, and bic_set_bfqq() is called with the freed
bic->bfqq.
Fix the problem by always freeing bfqq after bic_set_bfqq().
Fixes: 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'")
Reported-and-tested-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230130014136.591038-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
As part of nvmet_fc_ls_create_association there is a case where
nvmet_fc_alloc_target_queue fails right after a new association with an
admin queue is created. In this case, no one releases the get taken in
nvmet_fc_alloc_target_assoc. This fix is adding the missing put.
Signed-off-by: Amit Engel <Amit.Engel@dell.com>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull NVMe fixes from Christoph:
"nvme fixes for Linux 6.2
- flush initial scan_work for async probe (Keith Busch)
- fix passthrough csi check (Keith Busch)
- fix nvme-fc initialization order (Ross Lagerwall)"
* tag 'nvme-6.2-2023-01-26' of git://git.infradead.org/nvme:
nvme: fix passthrough csi check
nvme-pci: flush initial scan_work for async probe
nvme-fc: fix initialization order
The 'ublk_chr_class' is needed when deleting ublk char devices in
ublk_exit(), so move it after devices(idle) are removed.
Fixes the following warning reported by Harris, James R:
[ 859.178950] sysfs group 'power' not found for kobject 'ublkc0'
[ 859.178962] WARNING: CPU: 3 PID: 1109 at fs/sysfs/group.c:278 sysfs_remove_group+0x9c/0xb0
Reported-by: "Harris, James R" <james.r.harris@intel.com>
Fixes: 71f28f3136af ("ublk_drv: add io_uring based userspace block driver")
Link: https://lore.kernel.org/linux-block/Y9JlFmSgDl3+zy3N@T590/T/#t
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Jim Harris <james.r.harris@intel.com>
Link: https://lore.kernel.org/r/20230126115346.263344-1-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The namespace head saves the Command Set Indicator enum, so use that
instead of the Command Set Selected. The two values are not the same.
Fixes: 831ed60c2aca2d ("nvme: also return I/O command effects from nvme_command_effects")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull NVMe fixes from Christoph:
"nvme fixes for Linux 6.2
- fix controller shutdown regression in nvme-apple (Janne Grunau)
- fix a polling on timeout regression in nvme-pci (Keith Busch)"
* tag 'nvme-6.2-2023-01-20' of git://git.infradead.org/nvme:
nvme-pci: fix timeout request state check
nvme-apple: only reset the controller when RTKit is running
nvme-apple: reset controller during shutdown
The nvme device may have a namespace with the root partition, so make
sure we've completed scanning before returning from the async probe.
Fixes: eac3ef262941 ("nvme-pci: split the initial probe from the rest path")
Reported-by: Klaus Jensen <its@irrelevant.dk>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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