Revert "blk-mq: fix hctx/ctx kobject use-after-free"

This reverts commit 76d697d107.

The commit 76d697d107 causes general protection fault
reported from Bart Van Assche:

	https://lkml.org/lkml/2015/1/28/334

Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Ming Lei 2015-01-29 20:17:26 +08:00 committed by Jens Axboe
parent c59c961ca5
commit 74170118b2
2 changed files with 7 additions and 24 deletions

View File

@ -15,26 +15,6 @@
static void blk_mq_sysfs_release(struct kobject *kobj)
{
struct request_queue *q;
q = container_of(kobj, struct request_queue, mq_kobj);
free_percpu(q->queue_ctx);
}
static void blk_mq_ctx_release(struct kobject *kobj)
{
struct blk_mq_ctx *ctx;
ctx = container_of(kobj, struct blk_mq_ctx, kobj);
kobject_put(&ctx->queue->mq_kobj);
}
static void blk_mq_hctx_release(struct kobject *kobj)
{
struct blk_mq_hw_ctx *hctx;
hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
kfree(hctx);
}
struct blk_mq_ctx_sysfs_entry {
@ -338,13 +318,13 @@ static struct kobj_type blk_mq_ktype = {
static struct kobj_type blk_mq_ctx_ktype = {
.sysfs_ops = &blk_mq_sysfs_ops,
.default_attrs = default_ctx_attrs,
.release = blk_mq_ctx_release,
.release = blk_mq_sysfs_release,
};
static struct kobj_type blk_mq_hw_ktype = {
.sysfs_ops = &blk_mq_hw_sysfs_ops,
.default_attrs = default_hw_ctx_attrs,
.release = blk_mq_hctx_release,
.release = blk_mq_sysfs_release,
};
static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
@ -375,7 +355,6 @@ static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
return ret;
hctx_for_each_ctx(hctx, ctx, i) {
kobject_get(&q->mq_kobj);
ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
if (ret)
break;

View File

@ -1641,8 +1641,10 @@ static void blk_mq_free_hw_queues(struct request_queue *q,
struct blk_mq_hw_ctx *hctx;
unsigned int i;
queue_for_each_hw_ctx(q, hctx, i)
queue_for_each_hw_ctx(q, hctx, i) {
free_cpumask_var(hctx->cpumask);
kfree(hctx);
}
}
static int blk_mq_init_hctx(struct request_queue *q,
@ -2000,9 +2002,11 @@ void blk_mq_free_queue(struct request_queue *q)
percpu_ref_exit(&q->mq_usage_counter);
free_percpu(q->queue_ctx);
kfree(q->queue_hw_ctx);
kfree(q->mq_map);
q->queue_ctx = NULL;
q->queue_hw_ctx = NULL;
q->mq_map = NULL;