From 88b98287356762cc16c9ff6cd48116160a5d4dba Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 21 Jul 2014 21:34:30 -0700 Subject: drm/i915: fix freeze with blank screen booting highmem x86_64 boots and displays fine, but booting x86_32 with CONFIG_HIGHMEM has frozen with a blank screen throughout 3.16-rc on this ThinkPad T420s, with i915 generation 6 graphics. Fix 9d0a6fa6c5e6 ("drm/i915: add render state initialization"): kunmap() takes struct page * argument, not virtual address. Which the compiler kindly points out, if you use the appropriate u32 *batch, instead of silencing it with a void *. Why did bisection lead decisively to nearby 229b0489aa75 ("drm/i915: add null render states for gen6, gen7 and gen8")? Because the u32 deposited at that virtual address by the previous stub failed the PageHighMem test, and so did no harm. Signed-off-by: Hugh Dickins Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_gem_render_state.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/i915_gem_render_state.c b/drivers/gpu/drm/i915/i915_gem_render_state.c index 3521f998a178..34894b573064 100644 --- a/drivers/gpu/drm/i915/i915_gem_render_state.c +++ b/drivers/gpu/drm/i915/i915_gem_render_state.c @@ -31,7 +31,7 @@ struct i915_render_state { struct drm_i915_gem_object *obj; unsigned long ggtt_offset; - void *batch; + u32 *batch; u32 size; u32 len; }; @@ -80,7 +80,7 @@ free: static void render_state_free(struct i915_render_state *so) { - kunmap(so->batch); + kunmap(kmap_to_page(so->batch)); i915_gem_object_ggtt_unpin(so->obj); drm_gem_object_unreference(&so->obj->base); kfree(so); -- cgit v1.2.3