From: Lucas Stach <l.stach@pengutronix.de>
Date: Fri, 17 Nov 2017 17:51:19 +0100
Subject: drm/etnaviv: add lockdep annotations to buffer manipulation functions
Git-commit: b6d6223f5029d3c4fe466ce1711fe4cb23d06013
Patch-mainline: v4.16-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

When manipulating the kernel command buffer the GPU mutex must be held, as
otherwise different callers might try to replace the same part of the
buffer, wreacking havok in the GPU execution.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/etnaviv/etnaviv_buffer.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

--- a/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_buffer.c
@@ -100,6 +100,8 @@ static void etnaviv_cmd_select_pipe(stru
 {
 	u32 flush = 0;
 
+	lockdep_assert_held(&gpu->lock);
+
 	/*
 	 * This assumes that if we're switching to 2D, we're switching
 	 * away from 3D, and vice versa.  Hence, if we're switching to
@@ -166,6 +168,8 @@ u16 etnaviv_buffer_init(struct etnaviv_g
 {
 	struct etnaviv_cmdbuf *buffer = gpu->buffer;
 
+	lockdep_assert_held(&gpu->lock);
+
 	/* initialize buffer */
 	buffer->user_size = 0;
 
@@ -180,6 +184,8 @@ u16 etnaviv_buffer_config_mmuv2(struct e
 {
 	struct etnaviv_cmdbuf *buffer = gpu->buffer;
 
+	lockdep_assert_held(&gpu->lock);
+
 	buffer->user_size = 0;
 
 	if (gpu->identity.features & chipFeatures_PIPE_3D) {
@@ -215,6 +221,8 @@ void etnaviv_buffer_end(struct etnaviv_g
 	unsigned int waitlink_offset = buffer->user_size - 16;
 	u32 link_target, flush = 0;
 
+	lockdep_assert_held(&gpu->lock);
+
 	if (gpu->exec_state == ETNA_PIPE_2D)
 		flush = VIVS_GL_FLUSH_CACHE_PE2D;
 	else if (gpu->exec_state == ETNA_PIPE_3D)
@@ -257,6 +265,8 @@ void etnaviv_sync_point_queue(struct etn
 	unsigned int waitlink_offset = buffer->user_size - 16;
 	u32 dwords, target;
 
+	lockdep_assert_held(&gpu->lock);
+
 	/*
 	 * We need at most 3 dwords in the return target:
 	 * 1 event + 1 end + 1 wait + 1 link.
@@ -296,6 +306,8 @@ void etnaviv_buffer_queue(struct etnaviv
 	u32 link_target, link_dwords;
 	bool switch_context = gpu->exec_state != cmdbuf->exec_state;
 
+	lockdep_assert_held(&gpu->lock);
+
 	if (drm_debug & DRM_UT_DRIVER)
 		etnaviv_buffer_dump(gpu, buffer, 0, 0x50);