Revert "blk-mq: fix hctx/ctx kobject use-after-free"
This reverts commit 76d697d10769048e5721510100bf3a9413a56385.
The commit 76d697d10769048 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>
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 6774a0e..1630a20 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -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_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 @@
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;