| Message ID | 1460476663-24890-2-git-send-email-matthew.auld@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On ti, 2016-04-12 at 16:57 +0100, Matthew Auld wrote: > For the gen6/gen8_allocate_va_range functions remove the WARN_ON range > sanity checks in favour of simply hardening the allocation paths. This > also fixes the inconsistency in which we don't always handle the > potential overflow in our checks. > Not sure this is the right thing to do. I think I do prefer erroring out on invalid arguments as we're talking of internal programmer interface. Regards, Joonas > Cc: Chris Wilson <chris@chris-wilson.co.uk> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Signed-off-by: Matthew Auld <matthew.auld@intel.com> > --- > drivers/gpu/drm/i915/i915_gem_gtt.c | 17 ++++------------- > 1 file changed, 4 insertions(+), 13 deletions(-) > > diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c > index 5ed713d..fa583d5 100644 > --- a/drivers/gpu/drm/i915/i915_gem_gtt.c > +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c > @@ -1220,15 +1220,6 @@ static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm, > uint32_t pdpes = I915_PDPES_PER_PDP(dev); > int ret; > > - /* Wrap is never okay since we can only represent 48b, and we don't > - * actually use the other side of the canonical address space. > - */ > - if (WARN_ON(start + length < start)) > - return -ENODEV; > - > - if (WARN_ON(start + length > vm->total)) > - return -ENODEV; > - > ret = alloc_gen8_temp_bitmaps(&new_page_dirs, &new_page_tables, pdpes); > if (ret) > return ret; > @@ -1370,6 +1361,8 @@ static int gen8_alloc_va_range(struct i915_address_space *vm, > { > struct i915_hw_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); > > + length = min_t(uint64_t, length, vm->total); > + > if (USES_FULL_48BIT_PPGTT(vm->dev)) > return gen8_alloc_va_range_4lvl(vm, &ppgtt->pml4, start, length); > else > @@ -1860,11 +1853,9 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, > uint32_t pde, temp; > int ret; > > - if (WARN_ON(start_in + length_in > ppgtt->base.total)) > - return -ENODEV; > - > start = start_save = start_in; > - length = length_save = length_in; > + length = length_save = length_in = min_t(uint64_t, length_in, > + ppgtt->base.total); > > bitmap_zero(new_page_tables, I915_PDES); >
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 5ed713d..fa583d5 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1220,15 +1220,6 @@ static int gen8_alloc_va_range_3lvl(struct i915_address_space *vm, uint32_t pdpes = I915_PDPES_PER_PDP(dev); int ret; - /* Wrap is never okay since we can only represent 48b, and we don't - * actually use the other side of the canonical address space. - */ - if (WARN_ON(start + length < start)) - return -ENODEV; - - if (WARN_ON(start + length > vm->total)) - return -ENODEV; - ret = alloc_gen8_temp_bitmaps(&new_page_dirs, &new_page_tables, pdpes); if (ret) return ret; @@ -1370,6 +1361,8 @@ static int gen8_alloc_va_range(struct i915_address_space *vm, { struct i915_hw_ppgtt *ppgtt = i915_vm_to_ppgtt(vm); + length = min_t(uint64_t, length, vm->total); + if (USES_FULL_48BIT_PPGTT(vm->dev)) return gen8_alloc_va_range_4lvl(vm, &ppgtt->pml4, start, length); else @@ -1860,11 +1853,9 @@ static int gen6_alloc_va_range(struct i915_address_space *vm, uint32_t pde, temp; int ret; - if (WARN_ON(start_in + length_in > ppgtt->base.total)) - return -ENODEV; - start = start_save = start_in; - length = length_save = length_in; + length = length_save = length_in = min_t(uint64_t, length_in, + ppgtt->base.total); bitmap_zero(new_page_tables, I915_PDES);
For the gen6/gen8_allocate_va_range functions remove the WARN_ON range sanity checks in favour of simply hardening the allocation paths. This also fixes the inconsistency in which we don't always handle the potential overflow in our checks. Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Matthew Auld <matthew.auld@intel.com> --- drivers/gpu/drm/i915/i915_gem_gtt.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-)