From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00AA0C433E0 for ; Fri, 24 Jul 2020 21:00:10 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BCF2D206EB for ; Fri, 24 Jul 2020 21:00:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BCF2D206EB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=bugzilla.kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 14FE36EA03; Fri, 24 Jul 2020 21:00:10 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6E3666EA03 for ; Fri, 24 Jul 2020 21:00:09 +0000 (UTC) From: bugzilla-daemon@bugzilla.kernel.org To: dri-devel@lists.freedesktop.org Subject: [Bug 207383] [Regression] 5.7 amdgpu/polaris11 gpf: amdgpu_atomic_commit_tail Date: Fri, 24 Jul 2020 21:00:07 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: Video(DRI - non Intel) X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: blocking X-Bugzilla-Who: nicholas.kazlauskas@amd.com X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: drivers_video-dri@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" https://bugzilla.kernel.org/show_bug.cgi?id=207383 --- Comment #92 from Nicholas Kazlauskas (nicholas.kazlauskas@amd.com) --- This sounds very similar to a bug I fixed a year ago but that issue was with freeing the dc_state. https://bugzilla.kernel.org/show_bug.cgi?id=204181 1. Client requests non-blocking Commit #1, has a new dc_state #1, state is swapped, commit tail is deferred to work queue 2. Client requests non-blocking Commit #2, has a new dc_state #2, state is swapped, commit tail is deferred to work queue 3. Commit #2 work starts before Commit #1, commit tail finishes, atomic state is cleared, dc_state #1 is freed 4. Commit #1 work starts after Commit #2, uses dc_state #1, NULL pointer deref. This issue was fixed, but it occurred under similar conditions - heavy system load and frequent pageflipping. However, in the case of dm_state things can't be solved in the same manner. Commit #2 can't free Commit #1's commit - only the commit tail for Commit #1 can free it along with the IOCTL caller. I don't know if this is going down any of the deadlock paths in DRM core because that might trigger strange behavior as well with clearing/putting the dm_state. If someone who can reproduce this issue can produce a dmesg log with the DRM IOCTLs logged (I think drm.debug=0x54 should work) then I should be able to examine the IOCTL sequence in more detail. -- You are receiving this mail because: You are watching the assignee of the bug. _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel