[PATCH v2] drm/msm: Update global fault counter when faulty process has already ended

[Maíra Canal]

The global fault counter is no longer used since commit 12578c075f89
("drm/msm/gpu: Skip retired submits in recover worker"). However, it's
still needed, as we need to handle cases where a GPU fault occurs after
the faulting process has already ended.

Hence, increment the global fault counter when the submitting process
had already ended. This way, the number of faults returned by
MSM_PARAM_FAULTS will stay consistent.

While here, s/unusuable/unusable.

Fixes: 12578c075f89 ("drm/msm/gpu: Skip retired submits in recover worker")
Signed-off-by: Maíra Canal <mcanal at igalia.com>
---

v1 -> v2: https://lore.kernel.org/dri-devel/20250714230813.46279-1-mcanal@igalia.com/T/

* Don't delete the global fault, but instead, increment it when the we get
	a fault after the faulting process has ended (Rob Clark)
* Rewrite the commit message based on the changes.

 drivers/gpu/drm/msm/msm_gpu.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index c317b25a8162..416d47185ef0 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -465,6 +465,7 @@ static void recover_worker(struct kthread_work *work)
 	struct msm_gem_submit *submit;
 	struct msm_ringbuffer *cur_ring = gpu->funcs->active_ring(gpu);
 	char *comm = NULL, *cmd = NULL;
+	struct task_struct *task;
 	int i;
 
 	mutex_lock(&gpu->lock);
@@ -482,16 +483,20 @@ static void recover_worker(struct kthread_work *work)
 
 	/* Increment the fault counts */
 	submit->queue->faults++;
-	if (submit->vm) {
+
+	task = get_pid_task(submit->pid, PIDTYPE_PID);
+	if (!task)
+		gpu->global_faults++;
+	else {
 		struct msm_gem_vm *vm = to_msm_vm(submit->vm);
 
 		vm->faults++;
 
 		/*
 		 * If userspace has opted-in to VM_BIND (and therefore userspace
-		 * management of the VM), faults mark the VM as unusuable.  This
+		 * management of the VM), faults mark the VM as unusable. This
 		 * matches vulkan expectations (vulkan is the main target for
-		 * VM_BIND)
+		 * VM_BIND).
 		 */
 		if (!vm->managed)
 			msm_gem_vm_unusable(submit->vm);
-- 
2.50.0