linux-kernel - [PATCH 8/14] drm/i915: more struct

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>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 30 May 2011 17:46:59 -0700 (PDT)
From:	Hugh Dickins <hughd@...gle.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
cc:	Chris Wilson <chris@...is-wilson.co.uk>,
	Keith Packard <keithp@...thp.com>,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: [PATCH 8/14] drm/i915: more struct_mutex locking

When auditing the locking in i915_gem.c (for a prospective change which
I then abandoned), I noticed two places where struct_mutex is not held
across GEM object manipulations that would usually require it.  Since
one is in initial setup and the other in driver unload, I'm guessing
the mutex is not required for either; but post a patch in case it is.

Signed-off-by: Hugh Dickins <hughd@...gle.com>
Cc: Chris Wilson <chris@...is-wilson.co.uk>
Cc: Keith Packard <keithp@...thp.com>
---
 drivers/gpu/drm/i915/i915_dma.c      |    3 +--
 drivers/gpu/drm/i915/intel_overlay.c |    5 +++++
 2 files changed, 6 insertions(+), 2 deletions(-)

--- linux.orig/drivers/gpu/drm/i915/i915_dma.c	2011-05-30 13:56:09.972795920 -0700
+++ linux/drivers/gpu/drm/i915/i915_dma.c	2011-05-30 14:26:33.445838032 -0700
@@ -2182,9 +2182,8 @@ int i915_driver_unload(struct drm_device
 		/* Flush any outstanding unpin_work. */
 		flush_workqueue(dev_priv->wq);
 
-		i915_gem_free_all_phys_object(dev);
-
 		mutex_lock(&dev->struct_mutex);
+		i915_gem_free_all_phys_object(dev);
 		i915_gem_cleanup_ringbuffer(dev);
 		mutex_unlock(&dev->struct_mutex);
 		if (I915_HAS_FBC(dev) && i915_powersave)
--- linux.orig/drivers/gpu/drm/i915/intel_overlay.c	2011-05-30 13:56:09.972795920 -0700
+++ linux/drivers/gpu/drm/i915/intel_overlay.c	2011-05-30 14:26:33.449838050 -0700
@@ -1416,6 +1416,8 @@ void intel_setup_overlay(struct drm_devi
 		goto out_free;
 	overlay->reg_bo = reg_bo;
 
+	mutex_lock(&dev->struct_mutex);
+
 	if (OVERLAY_NEEDS_PHYSICAL(dev)) {
 		ret = i915_gem_attach_phys_object(dev, reg_bo,
 						  I915_GEM_PHYS_OVERLAY_REGS,
@@ -1440,6 +1442,8 @@ void intel_setup_overlay(struct drm_devi
                 }
 	}
 
+	mutex_unlock(&dev->struct_mutex);
+
 	/* init all values */
 	overlay->color_key = 0x0101fe;
 	overlay->brightness = -19;
@@ -1463,6 +1467,7 @@ void intel_setup_overlay(struct drm_devi
 out_unpin_bo:
 	i915_gem_object_unpin(reg_bo);
 out_free_bo:
+	mutex_unlock(&dev->struct_mutex);
 	drm_gem_object_unreference(&reg_bo->base);
 out_free:
 	kfree(overlay);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/