From: Pavel Machek Date: Mon, 28 Jul 2014 11:20:58 +0000 (+0200) Subject: drm/i915: work around warning in i915_gem_gtt X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=57007df74a547c68b3373861aa15efb861af6efc;p=deliverable%2Flinux.git drm/i915: work around warning in i915_gem_gtt Gcc warns that addr might be used uninitialized. It may not, but I see why gcc gets confused. Additionally, hiding code with side-effects inside WARN_ON() argument seems uncool, so I moved it outside. Signed-off-by: Pavel Machek [danvet: Add obligatory /* shuts up gcc */ comment.] Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 5188936bca0a..1411613f2174 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -1415,7 +1415,7 @@ static void gen8_ggtt_insert_entries(struct i915_address_space *vm, (gen8_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry; int i = 0; struct sg_page_iter sg_iter; - dma_addr_t addr = 0; + dma_addr_t addr = 0; /* shut up gcc */ for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) { addr = sg_dma_address(sg_iter.sg) + @@ -1461,7 +1461,7 @@ static void gen6_ggtt_insert_entries(struct i915_address_space *vm, (gen6_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry; int i = 0; struct sg_page_iter sg_iter; - dma_addr_t addr; + dma_addr_t addr = 0; for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) { addr = sg_page_iter_dma_address(&sg_iter); @@ -1475,9 +1475,10 @@ static void gen6_ggtt_insert_entries(struct i915_address_space *vm, * of NUMA access patterns. Therefore, even with the way we assume * hardware should work, we must keep this posting read for paranoia. */ - if (i != 0) - WARN_ON(readl(>t_entries[i-1]) != - vm->pte_encode(addr, level, true, flags)); + if (i != 0) { + unsigned long gtt = readl(>t_entries[i-1]); + WARN_ON(gtt != vm->pte_encode(addr, level, true, flags)); + } /* This next bit makes the above posting read even more important. We * want to flush the TLBs only after we're certain all the PTE updates