4.14-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit ca22f32a6296cbfa29de56328c8505560a18cfa8 ] Legacy behaviour was to allow non-page-aligned mmap requests, as does the linux mmap(2) implementation by virtue of automatically rounding up for the caller. To avoid breaking legacy userspace relax the newly introduced fix. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Fixes: 5c4604e757ba ("drm/i915: Prevent a race during I915_GEM_MMAP ioctl with WC set") Reported-by: Guenter Roeck <linux@xxxxxxxxxxxx> Cc: Adam Zabrocki <adamza@xxxxxxxxxxxxx> Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # v4.0+ Cc: Akash Goel <akash.goel@xxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20190305110409.28633-1-tvrtko.ursulin@xxxxxxxxxxxxxxx (cherry picked from commit a90e1948efb648f567444f87f3c19b2a0787affd) Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/i915/i915_gem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1640,7 +1640,8 @@ __vma_matches(struct vm_area_struct *vma if (vma->vm_file != filp) return false; - return vma->vm_start == addr && (vma->vm_end - vma->vm_start) == size; + return vma->vm_start == addr && + (vma->vm_end - vma->vm_start) == PAGE_ALIGN(size); } /**