From 7a00266f982e6d28b1bc0e838bb7c53baecb97eb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Roberto=20de=20Souza?= <jose.souza@intel.com>
Date: Wed, 23 Feb 2022 11:49:46 -0800
Subject: drm/i915: Check stolen memory size before calling drm_mm_init
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Git-commit: b8986c889e7ac26c57cb548f8f344456fa925a2f
Patch-mainline: v5.18-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
Add check for zero usable stolen memory before calling drm_mm_init
to support configurations where stolen memory exists but is fully
reserved.
Also skip memory test in cases that usable stolen is smaller than
page size(amount mapped and used to test memory).
v2:
- skiping test if available memory is smaller than page size (Lucas)
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Steve Carbonari <steven.carbonari@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220223194946.725328-1-jose.souza@intel.com
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 9 ++++++---
drivers/gpu/drm/i915/intel_memory_region.c | 8 ++++++--
2 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
index b9c3196b91ca..636cdf8a73b0 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -497,13 +497,16 @@ static int i915_gem_init_stolen(struct intel_memory_region *mem)
* memory, so just consider the start. */
reserved_total = stolen_top - reserved_base;
+ i915->stolen_usable_size =
+ resource_size(&i915->dsm) - reserved_total;
+
drm_dbg(&i915->drm,
"Memory reserved for graphics device: %lluK, usable: %lluK\n",
(u64)resource_size(&i915->dsm) >> 10,
- ((u64)resource_size(&i915->dsm) - reserved_total) >> 10);
+ (u64)i915->stolen_usable_size >> 10);
- i915->stolen_usable_size =
- resource_size(&i915->dsm) - reserved_total;
+ if (i915->stolen_usable_size == 0)
+ return 0;
/* Basic memrange allocator for stolen space. */
drm_mm_init(&i915->mm.stolen, 0, i915->stolen_usable_size);
diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c
index c70d7e286a51..16ab62d605b1 100644
--- a/drivers/gpu/drm/i915/intel_memory_region.c
+++ b/drivers/gpu/drm/i915/intel_memory_region.c
@@ -97,10 +97,14 @@ static int iomemtest(struct intel_memory_region *mem,
bool test_all,
const void *caller)
{
- resource_size_t last = resource_size(&mem->region) - PAGE_SIZE;
- resource_size_t page;
+ resource_size_t last, page;
int err;
+ if (resource_size(&mem->region) < PAGE_SIZE)
+ return 0;
+
+ last = resource_size(&mem->region) - PAGE_SIZE;
+
/*
* Quick test to check read/write access to the iomap (backing store).
*
--
2.38.1