Commit ab3edc67 authored by Andrzej Hajda's avatar Andrzej Hajda Committed by Rodrigo Vivi
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drm/i915/selftests: fix subtraction overflow bug 

On some machines hole_end can be small enough to cause subtraction
overflow. On the other side (addr + 2 * min_alignment) can overflow
in case of mock tests. This patch should handle both cases.

Fixes: e1c5f754 ("drm/i915: Avoid overflow in computing pot_hole loop termination")
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/3674


Signed-off-by: default avatarAndrzej Hajda <andrzej.hajda@intel.com>
Reviewed-by: default avatarAndi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: default avatarAndi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220624113528.2159210-1-andrzej.hajda@intel.com


Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
parent c877bed8

drivers/gpu/drm/i915/selftests/i915_gem_gtt.c

+1 −1
Original line number Diff line number Diff line
@@ -742,7 +742,7 @@ static int pot_hole(struct i915_address_space *vm, 
		u64 addr;



		for (addr = round_up(hole_start + min_alignment, step) - min_alignment;

		     addr <= round_down(hole_end - (2 * min_alignment), step) - min_alignment;

		     hole_end > addr && hole_end - addr >= 2 * min_alignment;

		     addr += step) {

			err = i915_vma_pin(vma, 0, 0, addr | flags);

			if (err) {