lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Date:   Tue, 12 Apr 2022 19:38:14 +0000
From:   Robert Beckett <bob.beckett@...labora.com>
To:     dri-devel@...ts.freedesktop.org, intel-gfx@...ts.freedesktop.org,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>
Cc:     Robert Beckett <bob.beckett@...labora.com>,
        Matthew Auld <matthew.auld@...el.com>,
        Thomas Hellström 
        <thomas.hellstrom@...ux.intel.com>, linux-kernel@...r.kernel.org
Subject: [PATCH v3 3/5] drm/i915: ttm move/clear logic fix

ttm managed buffers start off with system resource definitions and ttm_tt
tracking structures allocated (though unpopulated).
currently this prevents clearing of buffers on first move to desired
placements.

The desired behaviour is to clear user allocated buffers and any kernel
buffers that specifically requests it only.
Make the logic match the desired behaviour.

Signed-off-by: Robert Beckett <bob.beckett@...labora.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c | 22 +++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
index 9fe8132de3b2..9cf85f91edb5 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
@@ -3,6 +3,7 @@
  * Copyright © 2021 Intel Corporation
  */
 
+#include "drm/ttm/ttm_tt.h"
 #include <drm/ttm/ttm_bo_driver.h>
 
 #include "i915_deps.h"
@@ -470,6 +471,25 @@ __i915_ttm_move(struct ttm_buffer_object *bo,
 	return fence;
 }
 
+static bool
+allow_clear(struct drm_i915_gem_object *obj, struct ttm_tt *ttm, struct ttm_resource *dst_mem)
+{
+	/* never clear stolen */
+	if (dst_mem->mem_type == I915_PL_STOLEN)
+		return false;
+	/*
+	 * we want to clear user buffers and any kernel buffers
+	 * that specifically request clearing.
+	 */
+	if (obj->flags & I915_BO_ALLOC_USER)
+		return true;
+
+	if (ttm && ttm->page_flags & TTM_TT_FLAG_ZERO_ALLOC)
+		return true;
+
+	return false;
+}
+
 /**
  * i915_ttm_move - The TTM move callback used by i915.
  * @bo: The buffer object.
@@ -520,7 +540,7 @@ int i915_ttm_move(struct ttm_buffer_object *bo, bool evict,
 		return PTR_ERR(dst_rsgt);
 
 	clear = !i915_ttm_cpu_maps_iomem(bo->resource) && (!ttm || !ttm_tt_is_populated(ttm));
-	if (!(clear && ttm && !(ttm->page_flags & TTM_TT_FLAG_ZERO_ALLOC))) {
+	if (!clear || allow_clear(obj, ttm, dst_mem)) {
 		struct i915_deps deps;
 
 		i915_deps_init(&deps, GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN);
-- 
2.25.1

Powered by blists - more mailing lists