Merge remote-tracking branch 'airlied/drm-next' into drm-misc-next

Picking up drm-next @ 4.12-rc1 in order to apply Michal Hocko's vmalloc patch set

Signed-off-by: Sean Paul <seanpaul@chromium.org>

1 files changed, 14 insertions, 3 deletions

diff --git a/drivers/misc/cxl/api.c b/drivers/misc/cxl/api.c
index bcc030eacab7..1a138c83f877 100644
--- a/drivers/misc/cxl/api.c
+++ b/drivers/misc/cxl/api.c
@@ -14,6 +14,7 @@
 #include <linux/msi.h>
 #include <linux/module.h>
 #include <linux/mount.h>
+#include <linux/sched/mm.h>
 
 #include "cxl.h"
 
@@ -321,19 +322,29 @@ int cxl_start_context(struct cxl_context *ctx, u64 wed,
 
 	if (task) {
 		ctx->pid = get_task_pid(task, PIDTYPE_PID);
-		ctx->glpid = get_task_pid(task->group_leader, PIDTYPE_PID);
 		kernel = false;
 		ctx->real_mode = false;
+
+		/* acquire a reference to the task's mm */
+		ctx->mm = get_task_mm(current);
+
+		/* ensure this mm_struct can't be freed */
+		cxl_context_mm_count_get(ctx);
+
+		/* decrement the use count */
+		if (ctx->mm)
+			mmput(ctx->mm);
 	}
 
 	cxl_ctx_get();
 
 	if ((rc = cxl_ops->attach_process(ctx, kernel, wed, 0))) {
-		put_pid(ctx->glpid);
 		put_pid(ctx->pid);
-		ctx->glpid = ctx->pid = NULL;
+		ctx->pid = NULL;
 		cxl_adapter_context_put(ctx->afu->adapter);
 		cxl_ctx_put();
+		if (task)
+			cxl_context_mm_count_put(ctx);
 		goto out;
 	}