ivpu_device->context_xa is locked both in kernel thread and IRQ context. It requires XA_FLAGS_LOCK_IRQ flag to be passed during initialization otherwise the lock could be acquired from a thread and interrupted by an IRQ that locks it for the second time causing the deadlock.
This deadlock was reported by lockdep and observed in internal tests.
Fixes: 35b137630f08 ("accel/ivpu: Introduce a new DRM driver for Intel VPU") Cc: stable@vger.kernel.org # v6.3+ Signed-off-by: Jacek Lawrynowicz jacek.lawrynowicz@linux.intel.com --- drivers/accel/ivpu/ivpu_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/accel/ivpu/ivpu_drv.c b/drivers/accel/ivpu/ivpu_drv.c index 77283daaedd1..51d3f1a55d02 100644 --- a/drivers/accel/ivpu/ivpu_drv.c +++ b/drivers/accel/ivpu/ivpu_drv.c @@ -517,7 +517,7 @@ static int ivpu_dev_init(struct ivpu_device *vdev) vdev->context_xa_limit.min = IVPU_USER_CONTEXT_MIN_SSID; vdev->context_xa_limit.max = IVPU_USER_CONTEXT_MAX_SSID; atomic64_set(&vdev->unique_id_counter, 0); - xa_init_flags(&vdev->context_xa, XA_FLAGS_ALLOC); + xa_init_flags(&vdev->context_xa, XA_FLAGS_ALLOC | XA_FLAGS_LOCK_IRQ); xa_init_flags(&vdev->submitted_jobs_xa, XA_FLAGS_ALLOC1); xa_init_flags(&vdev->db_xa, XA_FLAGS_ALLOC1); lockdep_set_class(&vdev->submitted_jobs_xa.xa_lock, &submitted_jobs_xa_lock_class_key);
On 4/2/2024 4:49 AM, Jacek Lawrynowicz wrote:
ivpu_device->context_xa is locked both in kernel thread and IRQ context. It requires XA_FLAGS_LOCK_IRQ flag to be passed during initialization otherwise the lock could be acquired from a thread and interrupted by an IRQ that locks it for the second time causing the deadlock.
This deadlock was reported by lockdep and observed in internal tests.
Fixes: 35b137630f08 ("accel/ivpu: Introduce a new DRM driver for Intel VPU") Cc: stable@vger.kernel.org # v6.3+ Signed-off-by: Jacek Lawrynowicz jacek.lawrynowicz@linux.intel.com
Reviewed-by: Jeffrey Hugo quic_jhugo@quicinc.com
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