From: Matthew Auld Date: Wed, 27 Oct 2021 16:18:11 +0000 (+0100) Subject: drm/i915/clflush: disallow on discrete X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=c52b3b489783b3b244c8134204d542a4d07030b7;p=linux.git drm/i915/clflush: disallow on discrete We seem to have an unfortunate issue where we arrive from: i915_gem_object_flush_if_display+0x86/0xd0 [i915] intel_user_framebuffer_dirty+0x1a/0x50 [i915] drm_mode_dirtyfb_ioctl+0xfb/0x1b0 which can be before the pages are populated(and pinned for display), and so i915_gem_object_has_struct_page() might still return true, as per the ttm backend. We could re-order the later get_pages() call here, but since on discrete everything should already be coherent, with the exception of the display engine, and even there display surfaces must be allocated in device local-memory anyway, so there should in theory be no conceivable reason to ever call i915_gem_clflush_object() on discrete. References: https://gitlab.freedesktop.org/drm/intel/-/issues/4320 Signed-off-by: Matthew Auld Cc: Thomas Hellström Reviewed-by: Thomas Hellström Link: https://patchwork.freedesktop.org/patch/msgid/20211027161813.3094681-2-matthew.auld@intel.com --- diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c index 47586a8a1b732..fc76175bf9bee 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c @@ -69,6 +69,7 @@ static struct clflush *clflush_work_create(struct drm_i915_gem_object *obj) bool i915_gem_clflush_object(struct drm_i915_gem_object *obj, unsigned int flags) { + struct drm_i915_private *i915 = to_i915(obj->base.dev); struct clflush *clflush; assert_object_held(obj); @@ -80,7 +81,7 @@ bool i915_gem_clflush_object(struct drm_i915_gem_object *obj, * anything not backed by physical memory we consider to be always * coherent and not need clflushing. */ - if (!i915_gem_object_has_struct_page(obj)) { + if (!i915_gem_object_has_struct_page(obj) || IS_DGFX(i915)) { obj->cache_dirty = false; return false; } @@ -105,7 +106,7 @@ bool i915_gem_clflush_object(struct drm_i915_gem_object *obj, if (clflush) { i915_sw_fence_await_reservation(&clflush->base.chain, obj->base.resv, NULL, true, - i915_fence_timeout(to_i915(obj->base.dev)), + i915_fence_timeout(i915), I915_FENCE_GFP); dma_resv_add_excl_fence(obj->base.resv, &clflush->base.dma); dma_fence_work_commit(&clflush->base);