From: Ville Syrjälä <[email protected]> Take the minimum of the object size and the vma size and prefault only that much. Avoids a SIGBUS when mmapping only a portion of the object.
Prefaulting was introduced here: commit b90b91d87038f6b257b40a02b42ed4f9705e06f0 Author: Chris Wilson <[email protected]> Date: Tue Jun 10 12:14:40 2014 +0100 drm/i915: Prefault the entire object on first page fault Cc: Chris Wilson <[email protected]> Signed-off-by: Ville Syrjälä <[email protected]> --- drivers/gpu/drm/i915/i915_gem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 6f8c206..4ef80d1 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -1578,9 +1578,12 @@ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf) pfn >>= PAGE_SHIFT; if (!obj->fault_mappable) { + unsigned long size = min_t(unsigned long, + vma->vm_end - vma->vm_start, + obj->base.size); int i; - for (i = 0; i < obj->base.size >> PAGE_SHIFT; i++) { + for (i = 0; i < size >> PAGE_SHIFT; i++) { ret = vm_insert_pfn(vma, (unsigned long)vma->vm_start + i * PAGE_SIZE, pfn + i); -- 1.8.5.5 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
