From ccba2e850b0a29f3c8ab5063094125ed2fbd4e09 Mon Sep 17 00:00:00 2001
From: Deepak Nibade <dnibade@nvidia.com>
Date: Thu, 23 Jul 2020 12:22:56 +0530
Subject: [PATCH] gpu: nvgpu: add mutex to serialize profiler ioctl calls

Add new mutex prof->ioctl_lock to serialize all IOCTL calls on profiler
object. Running concurrent IOCTL calls could lead to races and
corrupted state.

Bug 2510974
Jira NVGPU-5360

Change-Id: I66a8d9078c35475a13442ccd34b61aca5b9c1d2b
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2389652
Reviewed-by: automaticguardword <automaticguardword@nvidia.com>
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-misra <svc-mobile-misra@nvidia.com>
Reviewed-by: svc-mobile-cert <svc-mobile-cert@nvidia.com>
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
GVS: Gerrit_Virtual_Submit
---
 drivers/gpu/nvgpu/common/profiler/profiler.c | 2 ++
 drivers/gpu/nvgpu/include/nvgpu/profiler.h   | 4 ++++
 drivers/gpu/nvgpu/os/linux/ioctl_prof.c      | 4 ++++
 3 files changed, 10 insertions(+)

diff --git a/drivers/gpu/nvgpu/common/profiler/profiler.c b/drivers/gpu/nvgpu/common/profiler/profiler.c
index 4d4428648..1ceccd30a 100644
--- a/drivers/gpu/nvgpu/common/profiler/profiler.c
+++ b/drivers/gpu/nvgpu/common/profiler/profiler.c
@@ -25,6 +25,7 @@
 #include <nvgpu/profiler.h>
 #include <nvgpu/atomic.h>
 #include <nvgpu/log.h>
+#include <nvgpu/lock.h>
 #include <nvgpu/kmem.h>
 #include <nvgpu/tsg.h>
 
@@ -52,6 +53,7 @@ int nvgpu_profiler_alloc(struct gk20a *g,
 	prof->scope = scope;
 	prof->g = g;
 
+	nvgpu_mutex_init(&prof->ioctl_lock);
 	nvgpu_init_list_node(&prof->prof_obj_entry);
 	nvgpu_list_add(&prof->prof_obj_entry, &g->profiler_objects);
 
diff --git a/drivers/gpu/nvgpu/include/nvgpu/profiler.h b/drivers/gpu/nvgpu/include/nvgpu/profiler.h
index bab004940..b01912195 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/profiler.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/profiler.h
@@ -26,6 +26,7 @@
 #ifdef CONFIG_NVGPU_PROFILER
 
 #include <nvgpu/list.h>
+#include <nvgpu/lock.h>
 #include <nvgpu/pm_reservation.h>
 
 struct gk20a;
@@ -57,6 +58,9 @@ struct nvgpu_profiler_object {
 	 */
 	bool context_init;
 
+	/* Lock to serialize IOCTL/DEVCTL calls */
+	struct nvgpu_mutex ioctl_lock;
+
 	/* If profiler object has reservation for each resource. */
 	bool reserved[NVGPU_PROFILER_PM_RESOURCE_TYPE_COUNT];
 
diff --git a/drivers/gpu/nvgpu/os/linux/ioctl_prof.c b/drivers/gpu/nvgpu/os/linux/ioctl_prof.c
index 67b09bf0c..0b96f1fd9 100644
--- a/drivers/gpu/nvgpu/os/linux/ioctl_prof.c
+++ b/drivers/gpu/nvgpu/os/linux/ioctl_prof.c
@@ -200,6 +200,8 @@ long nvgpu_prof_fops_ioctl(struct file *filp, unsigned int cmd,
 	nvgpu_log(g, gpu_dbg_prof, "Profiler handle %u received IOCTL cmd %u",
 		prof->prof_handle, cmd);
 
+	nvgpu_mutex_acquire(&prof->ioctl_lock);
+
 	nvgpu_speculation_barrier();
 
 	switch (cmd) {
@@ -218,6 +220,8 @@ long nvgpu_prof_fops_ioctl(struct file *filp, unsigned int cmd,
 		break;
 	}
 
+	nvgpu_mutex_release(&prof->ioctl_lock);
+
 	if ((err == 0) && (_IOC_DIR(cmd) & _IOC_READ))
 		err = copy_to_user((void __user *)arg,
 				   buf, _IOC_SIZE(cmd));