kernel_optimize_test/block
Tejun Heo b0814361a2 blkcg: make blkcg_print_stat() print stats only for online blkgs
blkcg_print_stat() iterates blkgs under RCU and doesn't test whether
the blkg is online.  This can call into pd_stat_fn() on a pd which is
still being initialized leading to an oops.

The heaviest operation - recursively summing up rwstat counters - is
already done while holding the queue_lock.  Expand queue_lock to cover
the other operations and skip the blkg if it isn't online yet.  The
online state is protected by both blkcg and queue locks, so this
guarantees that only online blkgs are processed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Roman Gushchin <guro@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Fixes: 903d23f0a3 ("blk-cgroup: allow controllers to output their own stats")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-11-06 17:08:38 -07:00
..
partitions
badblocks.c
bfq-cgroup.c
bfq-iosched.c
bfq-iosched.h
bfq-wf2q.c
bio-integrity.c
bio.c
blk-cgroup.c blkcg: make blkcg_print_stat() print stats only for online blkgs 2019-11-06 17:08:38 -07:00
blk-core.c
blk-exec.c
blk-flush.c block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-09-27 07:01:25 -06:00
blk-integrity.c
blk-ioc.c
blk-iocost.c iocost: don't nest spin_lock_irq in ioc_weight_write() 2019-10-31 11:40:57 -06:00
blk-iolatency.c
blk-lib.c
blk-map.c
blk-merge.c
blk-mq-cpumap.c
blk-mq-debugfs-zoned.c
blk-mq-debugfs.c
blk-mq-debugfs.h
blk-mq-pci.c
blk-mq-rdma.c
blk-mq-sched.c
blk-mq-sched.h
blk-mq-sysfs.c
blk-mq-tag.c
blk-mq-tag.h
blk-mq-virtio.c
blk-mq.c blk-mq: apply normal plugging for HDD 2019-09-27 11:40:21 -06:00
blk-mq.h
blk-pm.c
blk-pm.h
blk-rq-qos.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
blk-rq-qos.h blk-rq-qos: fix first node deletion of rq_qos_del() 2019-10-15 10:13:13 -06:00
blk-settings.c
blk-softirq.c
blk-stat.c
blk-stat.h
blk-sysfs.c rq-qos: get rid of redundant wbt_update_limits() 2019-09-27 01:13:10 -06:00
blk-throttle.c
blk-timeout.c
blk-wbt.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
blk-wbt.h
blk-zoned.c
blk.h block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-09-27 07:01:25 -06:00
bounce.c
bsg-lib.c
bsg.c
cmdline-parser.c
compat_ioctl.c
elevator.c block: Fix elv_support_iosched() 2019-10-14 13:54:09 -06:00
genhd.c
ioctl.c
ioprio.c
Kconfig
Kconfig.iosched
kyber-iosched.c
Makefile
mq-deadline.c
opal_proto.h
partition-generic.c
scsi_ioctl.c
sed-opal.c block: sed-opal: fix sparse warning: convert __be64 data 2019-10-03 14:21:32 -06:00
t10-pi.c