From: Matthew Auld Date: Mon, 18 Oct 2021 17:45:04 +0000 (+0100) Subject: drm/i915/userptr: add paranoid flush-on-acquire X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=63430347713a5ba48617687cc8b2aa1f01514432;p=linux.git drm/i915/userptr: add paranoid flush-on-acquire Even though userptr objects are always coherent with the GPU, with no way for userspace to change this with the set_caching ioctl, even on non-LLC platforms, there is still the 'Bypass LCC' mocs setting, which might permit reading the contents of main memory directly. Signed-off-by: Matthew Auld Cc: Thomas Hellström Reviewed-by: Thomas Hellström Link: https://patchwork.freedesktop.org/patch/msgid/20211018174508.2137279-5-matthew.auld@intel.com --- diff --git a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c index 887aca9e8dd23..3173c9f9a0402 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_userptr.c @@ -165,8 +165,11 @@ alloc_table: goto err; } - sg_page_sizes = i915_sg_dma_sizes(st->sgl); + WARN_ON_ONCE(!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_WRITE)); + if (i915_gem_object_can_bypass_llc(obj)) + obj->cache_dirty = true; + sg_page_sizes = i915_sg_dma_sizes(st->sgl); __i915_gem_object_set_pages(obj, st, sg_page_sizes); return 0;