From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Widawsky Subject: [PATCH 2/8] drm/i915: Round l3 parity reads down Date: Thu, 12 Sep 2013 22:28:28 -0700 Message-ID: <1379050122-12774-3-git-send-email-benjamin.widawsky@intel.com> References: <1379050122-12774-1-git-send-email-benjamin.widawsky@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail.bwidawsk.net (bwidawsk.net [166.78.191.112]) by gabe.freedesktop.org (Postfix) with ESMTP id F30FAE637E for ; Thu, 12 Sep 2013 22:28:51 -0700 (PDT) In-Reply-To: <1379050122-12774-1-git-send-email-benjamin.widawsky@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org Cc: bryan.j.bell@intel.com, Ben Widawsky , Ben Widawsky , vishnu.venkatesh@intel.com List-Id: intel-gfx@lists.freedesktop.org We always read a register for l3 parity reads, and we don't really want to ever let userspace trick us into giving back less than the dword. Writes are okay because we assume everything will be 0 filled, and as such, if a user really wants to write less than a dword, let them. Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_sysfs.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_sysfs.c b/drivers/gpu/drm/i915/i915_sysfs.c index c8c4112..9070f50 100644 --- a/drivers/gpu/drm/i915/i915_sysfs.c +++ b/drivers/gpu/drm/i915/i915_sysfs.c @@ -121,6 +121,8 @@ i915_l3_read(struct file *filp, struct kobject *kobj, uint32_t misccpctl; int i, ret; + count = round_down(count, 4); + ret = l3_access_valid(drm_dev, offset); if (ret) return ret; -- 1.8.4