From d42a738e5ae5a73212a83414648a4fae524117f3 Mon Sep 17 00:00:00 2001
From: Matthew Auld <matthew.auld@intel.com>
Date: Wed, 29 Jun 2022 18:43:44 +0100
Subject: [PATCH] drm/i915/error: skip non-mappable pages
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Skip capturing any lmem pages that can't be copied using the CPU. This
in now only best effort on platforms that have small BAR.

Testcase: igt@gem-exec-capture@capture-invisible
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220629174350.384910-7-matthew.auld@intel.com
---
 drivers/gpu/drm/i915/i915_gpu_error.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index f9b1969..52ea13f 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -1129,11 +1129,15 @@ i915_vma_coredump_create(const struct intel_gt *gt,
 		dma_addr_t dma;
 
 		for_each_sgt_daddr(dma, iter, vma_res->bi.pages) {
+			dma_addr_t offset = dma - mem->region.start;
 			void __iomem *s;
 
-			s = io_mapping_map_wc(&mem->iomap,
-					      dma - mem->region.start,
-					      PAGE_SIZE);
+			if (offset + PAGE_SIZE > mem->io_size) {
+				ret = -EINVAL;
+				break;
+			}
+
+			s = io_mapping_map_wc(&mem->iomap, offset, PAGE_SIZE);
 			ret = compress_page(compress,
 					    (void __force *)s, dst,
 					    true);
-- 
2.7.4