From: Andrzej Kacprowski <Andrzej.Kacprowski@xxxxxxxxx>
Multiple threads were accessing mmu cmd queue simultaneously
causing sporadic failures in ivpu_mmu_cmdq_sync() function.
Protect critical code with mmu mutex.
Reviewed-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
Signed-off-by: Andrzej Kacprowski <Andrzej.Kacprowski@xxxxxxxxx>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@xxxxxxxxxxxxxxx>
---
drivers/accel/ivpu/ivpu_mmu.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/accel/ivpu/ivpu_mmu.c b/drivers/accel/ivpu/ivpu_mmu.c
index b80bdded9fd79..5ea010568faa4 100644
--- a/drivers/accel/ivpu/ivpu_mmu.c
+++ b/drivers/accel/ivpu/ivpu_mmu.c
@@ -895,6 +895,9 @@ static int ivpu_mmu_evtq_disable(struct ivpu_device *vdev)
void ivpu_mmu_discard_events(struct ivpu_device *vdev)
{
+ struct ivpu_mmu_info *mmu = vdev->mmu;
+
+ mutex_lock(&mmu->lock);
/*
* Disable event queue (stop MMU from updating the producer)
* to allow synchronization of consumer and producer indexes
@@ -908,6 +911,8 @@ void ivpu_mmu_discard_events(struct ivpu_device *vdev)
ivpu_mmu_evtq_enable(vdev);
drm_WARN_ON_ONCE(&vdev->drm, vdev->mmu->evtq.cons != vdev->mmu->evtq.prod);
+
+ mutex_unlock(&mmu->lock);
}
int ivpu_mmu_disable_ssid_events(struct ivpu_device *vdev, u32 ssid)
@@ -920,6 +925,8 @@ int ivpu_mmu_disable_ssid_events(struct ivpu_device *vdev, u32 ssid)
if (ssid > IVPU_MMU_CDTAB_ENT_COUNT)
return -EINVAL;
+ mutex_lock(&mmu->lock);
+
entry = cdtab->base + (ssid * IVPU_MMU_CDTAB_ENT_SIZE);
val = READ_ONCE(entry[0]);
@@ -932,6 +939,8 @@ int ivpu_mmu_disable_ssid_events(struct ivpu_device *vdev, u32 ssid)
ivpu_mmu_cmdq_write_cfgi_all(vdev);
ivpu_mmu_cmdq_sync(vdev);
+ mutex_unlock(&mmu->lock);
+
return 0;
}
--
2.45.1
