From aaeb1ba041aedf2b58cd1303fd5fa9cf9173fa9b Mon Sep 17 00:00:00 2001 From: John Harrison Date: Fri, 5 Dec 2014 13:49:34 +0000 Subject: [PATCH] drm/i915: Zero fill the request structure There is a general theory that kzmalloc is better/safer than kmalloc, especially for interesting data structures. This change updates the request structure allocation to be zero filled. This also fixes crashes in the reset code. Quoting Mika's patch: "Clean the request structure on alloc. Otherwise we might end up referencing uninitialized fields. This is apparent when we try to cleanup the preallocated request on ring reset, before any request has been submitted to the ring. The request->ctx is foobar and we end up freeing the foobarness." Note that this fixes a regression introduced in commit 9eba5d4a1d79d5094321469479b4dbe418f60110 Author: John Harrison Date: Mon Nov 24 18:49:23 2014 +0000 drm/i915: Ensure OLS & PLR are always in sync References: https://bugs.freedesktop.org/show_bug.cgi?id=86959 References: https://bugs.freedesktop.org/show_bug.cgi?id=86962 References: https://bugs.freedesktop.org/show_bug.cgi?id=86992 Change-Id: I68715ef758025fab8db763941ef63bf60d7031e2 For: VIZ-4377 Signed-off-by: John Harrison Reviewed-by: Thomas Daniel Cc: Mika Kuoppala Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_lrc.c | 2 +- drivers/gpu/drm/i915/intel_ringbuffer.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c index 7986eb3e5027..782e97638ed8 100644 --- a/drivers/gpu/drm/i915/intel_lrc.c +++ b/drivers/gpu/drm/i915/intel_lrc.c @@ -885,7 +885,7 @@ static int logical_ring_alloc_request(struct intel_engine_cs *ring, if (ring->outstanding_lazy_request) return 0; - request = kmalloc(sizeof(*request), GFP_KERNEL); + request = kzalloc(sizeof(*request), GFP_KERNEL); if (request == NULL) return -ENOMEM; diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index f52101521653..882821913937 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -2032,7 +2032,7 @@ intel_ring_alloc_request(struct intel_engine_cs *ring) if (ring->outstanding_lazy_request) return 0; - request = kmalloc(sizeof(*request), GFP_KERNEL); + request = kzalloc(sizeof(*request), GFP_KERNEL); if (request == NULL) return -ENOMEM; -- 2.20.1