mirror of https://gitee.com/openkylin/linux.git
virtio/s390: fix race on airq_areas[]
The access to airq_areas was racy ever since the adapter interrupts got introduced to virtio-ccw, but since commit39c7dcb158
("virtio/s390: make airq summary indicators DMA") this became an issue in practice as well. Namely before that commit the airq_info that got overwritten was still functional. After that commit however the two infos share a summary_indicator, which aggravates the situation. Which means auto-online mechanism occasionally hangs the boot with virtio_blk. Signed-off-by: Halil Pasic <pasic@linux.ibm.com> Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Cc: stable@vger.kernel.org Fixes:96b14536d9
("virtio-ccw: virtio-ccw adapter interrupt support.") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This commit is contained in:
parent
1a2dcff881
commit
4f419eb142
|
@ -145,6 +145,8 @@ struct airq_info {
|
|||
struct airq_iv *aiv;
|
||||
};
|
||||
static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
|
||||
static DEFINE_MUTEX(airq_areas_lock);
|
||||
|
||||
static u8 *summary_indicators;
|
||||
|
||||
static inline u8 *get_summary_indicator(struct airq_info *info)
|
||||
|
@ -265,9 +267,11 @@ static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
|
|||
unsigned long bit, flags;
|
||||
|
||||
for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
|
||||
mutex_lock(&airq_areas_lock);
|
||||
if (!airq_areas[i])
|
||||
airq_areas[i] = new_airq_info(i);
|
||||
info = airq_areas[i];
|
||||
mutex_unlock(&airq_areas_lock);
|
||||
if (!info)
|
||||
return 0;
|
||||
write_lock_irqsave(&info->lock, flags);
|
||||
|
|
Loading…
Reference in New Issue