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author | Hou Tao <houtao1@huawei.com> | 2019-12-05 20:53:11 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-12-05 07:10:09 -0700 |
commit | 08802ed665e47243393f43501bdafa032112eb1c (patch) | |
tree | 59da0b969c07b20f0a3c947d6c38433dc3b8fac3 /block | |
parent | 08bdcc35f00c91b325195723cceaba0937a89ddf (diff) | |
download | lwn-08802ed665e47243393f43501bdafa032112eb1c.tar.gz lwn-08802ed665e47243393f43501bdafa032112eb1c.zip |
bfq-iosched: Ensure bio->bi_blkg is valid before using it
bio->bi_blkg will be NULL when the issue of the request
has bypassed the block layer as shown in the following oops:
Internal error: Oops: 96000005 [#1] SMP
CPU: 17 PID: 2996 Comm: scsi_id Not tainted 5.4.0 #4
Call trace:
percpu_counter_add_batch+0x38/0x4c8
bfqg_stats_update_legacy_io+0x9c/0x280
bfq_insert_requests+0xbac/0x2190
blk_mq_sched_insert_request+0x288/0x670
blk_execute_rq_nowait+0x140/0x178
blk_execute_rq+0x8c/0x140
sg_io+0x604/0x9c0
scsi_cmd_ioctl+0xe38/0x10a8
scsi_cmd_blk_ioctl+0xac/0xe8
sd_ioctl+0xe4/0x238
blkdev_ioctl+0x590/0x20e0
block_ioctl+0x60/0x98
do_vfs_ioctl+0xe0/0x1b58
ksys_ioctl+0x80/0xd8
__arm64_sys_ioctl+0x40/0x78
el0_svc_handler+0xc4/0x270
so ensure its validity before using it.
Fixes: fd41e60331b1 ("bfq-iosched: stop using blkg->stat_bytes and ->stat_ios")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r-- | block/bfq-cgroup.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c index cea0ae12f937..e1419edde2ec 100644 --- a/block/bfq-cgroup.c +++ b/block/bfq-cgroup.c @@ -351,6 +351,9 @@ void bfqg_stats_update_legacy_io(struct request_queue *q, struct request *rq) { struct bfq_group *bfqg = blkg_to_bfqg(rq->bio->bi_blkg); + if (!bfqg) + return; + blkg_rwstat_add(&bfqg->stats.bytes, rq->cmd_flags, blk_rq_bytes(rq)); blkg_rwstat_add(&bfqg->stats.ios, rq->cmd_flags, 1); } |