From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 14DCD3DDDCD for ; Fri, 8 May 2026 12:40:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778244052; cv=none; b=U/jK8TOSiAlXBbBBTSt3nkFbpHjjViKHiaycOTE+DTm2uYnSbxWWiFZMrC8dbb8XYdXs7289NAl1w37pfJu24Xxeupmm4N/sCCajCi2uHgNwLTF1GDhxdzXmgIuAfe0r2pbN/3jSUfDhjP+qd2DV6MwQK7Py4bsEmxQwY6rgwWo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778244052; c=relaxed/simple; bh=2sJkROZAh6Hff/DaVQBve9t+vJREpqTKtF9lHNA9KHE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=o5S76QZemL/oz/qpZyuMDNaDrSxI+FmSsCjPGusz6Fr5ECqJ3bVZoaD4x2eI/D/sOyB8wuIXBhJvEHBpejef1w5gSEuWH9FmexXXBlgmtUyJIoIDCrB5eVQ7aFsqLY8fCs+9J97SsDBkc+OWSsn03f2Gn8toAfC3OHH9hkcpyq0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=AjS48Seo; arc=none smtp.client-ip=192.198.163.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="AjS48Seo" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1778244050; x=1809780050; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=2sJkROZAh6Hff/DaVQBve9t+vJREpqTKtF9lHNA9KHE=; b=AjS48SeogkR7/IgOQ0ars9rsXjoJNup8gQbDWf9fwxaHfGXg5W740juG ax9CfHIojBfFpbXeH455E9mX57HDrMDfvJJQ28RU9Qt9BuQy5XKp81Na8 gcoR9CSnD5aAHqLFmbzsdBQFOgvBLyx3IbwJ8dkjFTDWegyY6/Gq0PoxP 7FyDlSl6BR+c41qOOoPE1tlPdURVYrTgJhsiw2WONJya1iqQN4z7ITX5H kwFUqKDUHMqHrH+k9VkmtJgUDQUs09PFWzl3Javsl6vSOAFwLLX2K9Tfx CISOaBo2RX9RNSywKfMkOKReUmhkkRn9XvQ6bKUtockoJKcCZ8zTvbeCW w==; X-CSE-ConnectionGUID: p9lL8jArSeaMTgo92kt53w== X-CSE-MsgGUID: pgCKLjDoSm+8Ylbv+3iyqg== X-IronPort-AV: E=McAfee;i="6800,10657,11779"; a="79317373" X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="79317373" Received: from fmviesa002.fm.intel.com ([10.60.135.142]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 05:40:49 -0700 X-CSE-ConnectionGUID: atym7dInQ7ey/bmOeotN3w== X-CSE-MsgGUID: r3K7ItInTs6RKGjTxwOUXg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,223,1770624000"; d="scan'208";a="260201936" Received: from abityuts-desk.ger.corp.intel.com (HELO localhost) ([10.245.244.67]) by fmviesa002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 May 2026 05:40:47 -0700 Date: Fri, 8 May 2026 14:40:45 +0200 From: Andi Shyti To: Sebastian Brzezinka Cc: intel-gfx@lists.freedesktop.org, andi.shyti@linux.intel.com, krzysztof.karas@intel.com, stable@vger.kernel.org Subject: Re: [PATCH] drm/i915: skip __i915_request_skip() for already signaled requests Message-ID: References: Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hi Sebastian, On Thu, Apr 16, 2026 at 01:31:18PM +0200, Sebastian Brzezinka wrote: > After a GPU reset the HWSP is zeroed, so previously completed > requests appear incomplete. If such a request is picked up during > reset_rewind() and marked guilty, i915_request_set_error_once() > returns early (fence already signaled), leaving fence.error without > a fatal error code. The subsequent __i915_request_skip() then hits: > ``` > GEM_BUG_ON(!fatal_error(rq->fence.error)) > ``` > > Fixes a kernel BUG observed on Sandy Bridge (Gen6) during > heartbeat-triggered engine resets. > ``` > kernel BUG at drivers/gpu/drm/i915/i915_request.c:556! > RIP: __i915_request_skip+0x15e/0x1d0 [i915] > ... > __i915_request_reset+0x212/0xa70 [i915] > reset_rewind+0xe4/0x280 [i915] > intel_gt_reset+0x30d/0x5b0 [i915] > heartbeat+0x516/0x530 [i915] > ``` > > Guard __i915_request_skip() with i915_request_signaled(), if the > fence is already signaled, the ring content is committed and there > is nothing left to skip. > > Cc: stable@vger.kernel.org > Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/work_items/13729 > Fixes: 36e191f0644b ("drm/i915: Apply i915_request_skip() on submission") > Signed-off-by: Sebastian Brzezinka Merged to drm-intel-gt-next. Thanks, Andi