1 files changed, 56 insertions, 17 deletions

diff --git a/drivers/gpu/arm/mali/context/mali_kbase_context.c b/drivers/gpu/arm/mali/context/mali_kbase_context.c
index f681b8a466b3c6..8e2eac80864dbd 100644
--- a/drivers/gpu/arm/mali/context/mali_kbase_context.c
+++ b/drivers/gpu/arm/mali/context/mali_kbase_context.c
@@ -22,6 +22,16 @@
 /*
  * Base kernel context APIs
  */
+#include <linux/version.h>
+#if KERNEL_VERSION(4, 11, 0) <= LINUX_VERSION_CODE
+#include <linux/sched/task.h>
+#endif
+
+#if KERNEL_VERSION(4, 19, 0) <= LINUX_VERSION_CODE
+#include <linux/sched/signal.h>
+#else
+#include <linux/sched.h>
+#endif
 
 #include <mali_kbase.h>
 #include <gpu/mali_kbase_gpu_regmap.h>
@@ -130,18 +140,47 @@ int kbase_context_common_init(struct kbase_context *kctx)
 	kbase_disjoint_event(kctx->kbdev);
 
 	kctx->process_mm = NULL;
+	kctx->task = NULL;
 	atomic_set(&kctx->nonmapped_pages, 0);
 	atomic_set(&kctx->permanent_mapped_pages, 0);
 	kctx->tgid = current->tgid;
 	kctx->pid = current->pid;
 
 	/* Check if this is a Userspace created context */
-	if (likely(kctx->filp)) {
-		/* This merely takes a reference on the mm_struct and not on the
-		 * address space and so won't block the freeing of address space
-		 * on process exit.
-		 */
-		mmgrab(current->mm);
+	if (likely(kctx->kfile)) {
+		struct pid *pid_struct;
+
+		rcu_read_lock();
+		pid_struct = get_pid(task_tgid(current));
+		if (likely(pid_struct)) {
+			struct task_struct *task = pid_task(pid_struct, PIDTYPE_PID);
+
+			if (likely(task)) {
+				/* Take a reference on the task to avoid slow lookup
+				 * later on from the page allocation loop.
+				 */
+				get_task_struct(task);
+				kctx->task = task;
+			} else {
+				dev_err(kctx->kbdev->dev,
+					"Failed to get task pointer for %s/%d",
+					current->comm, current->pid);
+				err = -ESRCH;
+			}
+
+			put_pid(pid_struct);
+		} else {
+			dev_err(kctx->kbdev->dev,
+				"Failed to get pid pointer for %s/%d",
+				current->comm, current->pid);
+			err = -ESRCH;
+		}
+		rcu_read_unlock();
+
+		if (unlikely(err))
+			return err;
+
+		kbase_mem_mmgrab();
 		kctx->process_mm = current->mm;
 	}
 
@@ -155,7 +194,6 @@ int kbase_context_common_init(struct kbase_context *kctx)
 	spin_lock_init(&kctx->waiting_soft_jobs_lock);
 	INIT_LIST_HEAD(&kctx->waiting_soft_jobs);
 
-	init_waitqueue_head(&kctx->event_queue);
 	atomic_set(&kctx->event_count, 0);
 
 #if !MALI_USE_CSF
@@ -177,16 +215,17 @@ int kbase_context_common_init(struct kbase_context *kctx)
 	kctx->id = atomic_add_return(1, &(kctx->kbdev->ctx_num)) - 1;
 
 	mutex_lock(&kctx->kbdev->kctx_list_lock);
-
 	err = kbase_insert_kctx_to_process(kctx);
+	mutex_unlock(&kctx->kbdev->kctx_list_lock);
 	if (err) {
-		dev_err(kctx->kbdev->dev, "(err:%d) failed to insert kctx to kbase_process", err);
-		if (likely(kctx->filp))
+		dev_err(kctx->kbdev->dev,
+			"(err:%d) failed to insert kctx to kbase_process", err);
+		if (likely(kctx->kfile)) {
 			mmdrop(kctx->process_mm);
+			put_task_struct(kctx->task);
+		}
 	}
 
-	mutex_unlock(&kctx->kbdev->kctx_list_lock);
-
 	return err;
 }
 
@@ -271,18 +310,18 @@ void kbase_context_common_term(struct kbase_context *kctx)
 	kbase_remove_kctx_from_process(kctx);
 	mutex_unlock(&kctx->kbdev->kctx_list_lock);
 
-	if (likely(kctx->filp))
+	if (likely(kctx->kfile)) {
 		mmdrop(kctx->process_mm);
+		put_task_struct(kctx->task);
+	}
 
 	KBASE_KTRACE_ADD(kctx->kbdev, CORE_CTX_DESTROY, kctx, 0u);
 }
 
 int kbase_context_mem_pool_group_init(struct kbase_context *kctx)
 {
-	return kbase_mem_pool_group_init(&kctx->mem_pools,
-		kctx->kbdev,
-		&kctx->kbdev->mem_pool_defaults,
-		&kctx->kbdev->mem_pools);
+	return kbase_mem_pool_group_init(&kctx->mem_pools, kctx->kbdev,
+					 &kctx->kbdev->mem_pool_defaults, &kctx->kbdev->mem_pools);
 }
 
 void kbase_context_mem_pool_group_term(struct kbase_context *kctx)