diff options
authorChris Wilson <chris@chris-wilson.co.uk>2017-10-16 21:27:32 +0100
committerRodrigo Vivi <rodrigo.vivi@intel.com>2017-10-18 08:11:35 -0700
commitca8d7822054287352c41ff38f656e68fef959732 (patch)
parent038daf5556a486cefc7a239ca4528003a5a4ef00 (diff)
drm/i915: Report -EFAULT before pwrite fast path into shmemfs
When pwriting into shmemfs, the fast path pagecache_write does not notice when it is writing to beyond the end of the truncated shmemfs inode. Report -EFAULT directly when we try to use pwrite into the !I915_MADV_WILLNEED object. Fixes: 7c55e2c5772d ("drm/i915: Use pagecache write to prepopulate shmemfs from pwrite-ioctl") Testcase: igt/gem_madvise/dontneed-before-pwrite Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.william.auld@gmail.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171016202732.25459-1-chris@chris-wilson.co.uk (cherry picked from commit a6d65e451cc4e7127698384868a4447ee7be7d16) Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index af289d35b77a..32e857dc507c 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2657,6 +2657,9 @@ i915_gem_object_pwrite_gtt(struct drm_i915_gem_object *obj,
if (READ_ONCE(obj->mm.pages))
return -ENODEV;
+ if (obj->mm.madv != I915_MADV_WILLNEED)
+ return -EFAULT;
/* Before the pages are instantiated the object is treated as being
* in the CPU domain. The pages will be clflushed as required before
* use, and we can freely write into the pages directly. If userspace