drm/msm: Add a way to override processes comm/cmdline

In the cause of using the GPU via virtgpu, the host side process is really a sort of proxy, and not terribly interesting from the PoV of crash/fault logging. Add a way to override these per process so that we can see the guest process's name. v2: Handle kmalloc failure, add comment to explain kstrdup returns NULL if passed NULL [Dan Carpenter]

Rob Clark committed 4 years ago

Commit d4726d71 parent 39ba0c05 files · +60 −5Browse files

Unified · Split

5 files

drivers/gpu/drm/msm/adreno/adreno_gpu.c +40 −3
drivers/gpu/drm/msm/msm_gpu.c +10 −2
drivers/gpu/drm/msm/msm_gpu.h +6 −0
drivers/gpu/drm/msm/msm_submitqueue.c +2 −0
include/uapi/drm/msm_drm.h +2 −0

drivers/gpu/drm/msm/adreno/adreno_gpu.c+40−3

@@ -290,11 +290,48 @@ int adreno_get_param(struct msm_gpu gpu, struct msm_file_private ctx, · 289 unmodified lines
290	290	int adreno_set_param(struct msm_gpu gpu, struct msm_file_private ctx,
291	291	uint32_t param, uint64_t value, uint32_t len)
292	292	{
293		− /* No pointer params yet */
294		− if (len != 0)
295		− return -EINVAL;
	293	+ switch (param) {
	294	+ case MSM_PARAM_COMM:
	295	+ case MSM_PARAM_CMDLINE:
	296	+ /* kstrdup_quotable_cmdline() limits to PAGE_SIZE, so
	297	+ * that should be a reasonable upper bound
	298	+ */
	299	+ if (len > PAGE_SIZE)
	300	+ return -EINVAL;
	301	+ break;
	302	+ default:
	303	+ if (len != 0)
	304	+ return -EINVAL;
	305	+ }
296	306
297	307	switch (param) {
	308	+ case MSM_PARAM_COMM:
	309	+ case MSM_PARAM_CMDLINE: {
	310	+ char str, *paramp;
	311	+
	312	+ str = kmalloc(len + 1, GFP_KERNEL);
	313	+ if (!str)
	314	+ return -ENOMEM;
	315	+
	316	+ if (copy_from_user(str, u64_to_user_ptr(value), len)) {
	317	+ kfree(str);
	318	+ return -EFAULT;
	319	+ }
	320	+
	321	+ /* Ensure string is null terminated: */
	322	+ str[len] = '\0';
	323	+
	324	+ if (param == MSM_PARAM_COMM) {
	325	+ paramp = &ctx->comm;
	326	+ } else {
	327	+ paramp = &ctx->cmdline;
	328	+ }
	329	+
	330	+ kfree(*paramp);
	331	+ *paramp = str;
	332	+
	333	+ return 0;
	334	+ }
298	335	case MSM_PARAM_SYSPROF:
299	336	if (!capable(CAP_SYS_ADMIN))
300	337	return -EPERM;

drivers/gpu/drm/msm/msm_gpu.c+10−2

@@ -353,14 +353,22 @@ static void retire_submits(struct msm_gpu *gpu); · 352 unmodified lines
353	353
354	354	static void get_comm_cmdline(struct msm_gem_submit submit, char comm, char *cmd)
355	355	{
	356	+ struct msm_file_private *ctx = submit->queue->ctx;
356	357	struct task_struct *task;
357	358
	359	+ /* Note that kstrdup will return NULL if argument is NULL: */
	360	+ *comm = kstrdup(ctx->comm, GFP_KERNEL);
	361	+ *cmd = kstrdup(ctx->cmdline, GFP_KERNEL);
	362	+
358	363	task = get_pid_task(submit->pid, PIDTYPE_PID);
359	364	if (!task)
360	365	return;
361	366
362		− *comm = kstrdup(task->comm, GFP_KERNEL);
363		− *cmd = kstrdup_quotable_cmdline(task, GFP_KERNEL);
	367	+ if (!*comm)
	368	+ *comm = kstrdup(task->comm, GFP_KERNEL);
	369	+
	370	+ if (!*cmd)
	371	+ *cmd = kstrdup_quotable_cmdline(task, GFP_KERNEL);
364	372
365	373	put_task_struct(task);
366	374	}

drivers/gpu/drm/msm/msm_gpu.h+6−0

@@ -355,6 +355,12 @@ struct msm_file_private { · 354 unmodified lines
355	355	*/
356	356	int sysprof;
357	357
	358	+ /** comm: Overridden task comm, see MSM_PARAM_COMM */
	359	+ char *comm;
	360	+
	361	+ /** cmdline: Overridden task cmdline, see MSM_PARAM_CMDLINE */
	362	+ char *cmdline;
	363	+
358	364	/**
359	365	* entities:
360	366	*

drivers/gpu/drm/msm/msm_submitqueue.c+2−0

@@ -61,6 +61,8 @@ void __msm_file_private_destroy(struct kref *kref) · 60 unmodified lines
61	61	}
62	62
63	63	msm_gem_address_space_put(ctx->aspace);
	64	+ kfree(ctx->comm);
	65	+ kfree(ctx->cmdline);
64	66	kfree(ctx);
65	67	}
66	68

include/uapi/drm/msm_drm.h+2−0

@@ -82,6 +82,8 @@ struct drm_msm_timespec { · 81 unmodified lines
82	82	#define MSM_PARAM_FAULTS 0x09 /* RO */
83	83	#define MSM_PARAM_SUSPENDS 0x0a /* RO */
84	84	#define MSM_PARAM_SYSPROF 0x0b /* WO: 1 preserves perfcntrs, 2 also disables suspend */
	85	+#define MSM_PARAM_COMM 0x0c /* WO: override for task->comm */
	86	+#define MSM_PARAM_CMDLINE 0x0d /* WO: override for task cmdline */
85	87
86	88	/* For backwards compat. The original support for preemption was based on
87	89	* a single ring per priority level so # of priority levels equals the #