From 357480ce2fe4dc11ff0b77706d77e2319c96fe31 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Sat, 25 Feb 2017 18:11:20 +0000 Subject: [PATCH] drm/i915: Assert we do not overflow 4lvl page directories Before looking up the page directory entry, check we are still within bounds. Signed-off-by: Chris Wilson Cc: Matthew Auld Reviewed-by: Matthew Auld Link: http://patchwork.freedesktop.org/patch/msgid/20170225181122.4788-2-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_gtt.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 24fa262..e6e0dfa 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -830,6 +830,7 @@ gen8_ppgtt_insert_pte_entries(struct i915_hw_ppgtt *ppgtt, gen8_pte_t *vaddr; bool ret; + GEM_BUG_ON(pdpe >= I915_PDPES_PER_PDP(vm)); pd = pdp->page_directory[pdpe]; vaddr = kmap_atomic_px(pd->page_table[pde]); do { @@ -854,8 +855,7 @@ gen8_ppgtt_insert_pte_entries(struct i915_hw_ppgtt *ppgtt, break; } - GEM_BUG_ON(!i915_vm_is_48bit(&ppgtt->base) && - pdpe >= GEN8_LEGACY_PDPES); + GEM_BUG_ON(pdpe >= I915_PDPES_PER_PDP(vm)); pd = pdp->page_directory[pdpe]; pde = 0; } @@ -904,7 +904,7 @@ static void gen8_ppgtt_insert_4lvl(struct i915_address_space *vm, while (gen8_ppgtt_insert_pte_entries(ppgtt, pdps[pml4e++], &iter, start, cache_level)) - ; + GEM_BUG_ON(pml4e >= GEN8_PML4ES_PER_PML4); } static void gen8_free_page_tables(struct i915_address_space *vm, -- 2.7.4