From patchwork Wed Jan 30 21:57:07 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herton Ronaldo Krzesinski X-Patchwork-Id: 217039 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id DE3FD2C0295 for ; Thu, 31 Jan 2013 10:12:19 +1100 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U0fed-0008RZ-19; Wed, 30 Jan 2013 21:57:15 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1U0fea-0008QS-4y for kernel-team@lists.ubuntu.com; Wed, 30 Jan 2013 21:57:12 +0000 Received: from 189.58.14.63.dynamic.adsl.gvt.net.br ([189.58.14.63] helo=canonical.com) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1U0feZ-0004rH-0q; Wed, 30 Jan 2013 21:57:11 +0000 From: Herton Ronaldo Krzesinski To: Chris Wilson Subject: [ 3.5.y.z extended stable ] Patch "drm/i915: Invalidate the relocation presumed_offsets along" has been added to staging queue Date: Wed, 30 Jan 2013 19:57:07 -0200 Message-Id: <1359583027-16992-1-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 X-Extended-Stable: 3.5 Cc: Daniel Vetter , kernel-team@lists.ubuntu.com, Daniel Vetter X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com This is a note to let you know that I have just added a patch titled drm/i915: Invalidate the relocation presumed_offsets along to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Herton ------ From 1562e9ee4e0a36ee6bb7ff6b10a9a58d0bf39660 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 15 Jan 2013 16:17:54 +0000 Subject: [PATCH] drm/i915: Invalidate the relocation presumed_offsets along the slow path commit 262b6d363fcff16359c93bd58c297f961f6e6273 upstream. In the slow path, we are forced to copy the relocations prior to acquiring the struct mutex in order to handle pagefaults. We forgo copying the new offsets back into the relocation entries in order to prevent a recursive locking bug should we trigger a pagefault whilst holding the mutex for the reservations of the execbuffer. Therefore, we need to reset the presumed_offsets just in case the objects are rebound back into their old locations after relocating for this exexbuffer - if that were to happen we would assume the relocations were valid and leave the actual pointers to the kernels dangling, instant hang. Fixes regression from commit bcf50e2775bbc3101932d8e4ab8c7902aa4163b4 Author: Chris Wilson Date: Sun Nov 21 22:07:12 2010 +0000 drm/i915: Handle pagefaults in execbuffer user relocations Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55984 Signed-off-by: Chris Wilson Cc: Daniel Vetter Signed-off-by: Daniel Vetter Signed-off-by: Herton Ronaldo Krzesinski --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) -- 1.7.9.5 diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c index 3debf95..fadd6d6 100644 --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -749,6 +749,8 @@ i915_gem_execbuffer_relocate_slow(struct drm_device *dev, total = 0; for (i = 0; i < count; i++) { struct drm_i915_gem_relocation_entry __user *user_relocs; + u64 invalid_offset = (u64)-1; + int j; user_relocs = (void __user *)(uintptr_t)exec[i].relocs_ptr; @@ -759,6 +761,25 @@ i915_gem_execbuffer_relocate_slow(struct drm_device *dev, goto err; } + /* As we do not update the known relocation offsets after + * relocating (due to the complexities in lock handling), + * we need to mark them as invalid now so that we force the + * relocation processing next time. Just in case the target + * object is evicted and then rebound into its old + * presumed_offset before the next execbuffer - if that + * happened we would make the mistake of assuming that the + * relocations were valid. + */ + for (j = 0; j < exec[i].relocation_count; j++) { + if (copy_to_user(&user_relocs[j].presumed_offset, + &invalid_offset, + sizeof(invalid_offset))) { + ret = -EFAULT; + mutex_lock(&dev->struct_mutex); + goto err; + } + } + reloc_offset[i] = total; total += exec[i].relocation_count; }