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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 699E0C4338F for ; Mon, 9 Aug 2021 13:38:45 +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 D8E1A61019 for ; Mon, 9 Aug 2021 13:38:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D8E1A61019 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ffwll.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F1C9189B5F; Mon, 9 Aug 2021 13:38:43 +0000 (UTC) Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by gabe.freedesktop.org (Postfix) with ESMTPS id 958D189B5F for ; Mon, 9 Aug 2021 13:38:42 +0000 (UTC) Received: by mail-wr1-x429.google.com with SMTP id f5so5714913wrm.13 for ; Mon, 09 Aug 2021 06:38:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=PUoT48Kepu/WtsZ2zSXdg3rVEV6q2hzCreGMpVRHbBY=; b=dRDp3P0MjiNOTlyUFXjf9e+528S552qdXJ7krg52p0OSY36FdlpRvaHvEY1J4HZpfx cXwGcrKEaXw0BbV2yplnU8EM9AwDasAVq2p8sRVh9dInVZOonHVH20GOp1tjv3zydsc/ hTfrwT30/9D+TAxgkiulYHv1IuEc3r9br+Ces= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=PUoT48Kepu/WtsZ2zSXdg3rVEV6q2hzCreGMpVRHbBY=; b=UqmUhZnrp6cbnkkBiBLt0+U82YTEJV0gcZtqupScVGaEzs8BiolZQ2HanuqT/jArPS jbFJeiVivmLmIGtZVbIFOxkIS9384nPdEUL98nbHZh5JoIVRpZgy3rX55h55gvd+U+2F SPRLF357/3NSPNCwn8/2Y0Yj1D/8t2pueak7VAKOfq58fU1bKZ20quyiZVZaSVuO07EF 5slpsH+xggILkBZcYpflMgsJl36L7tdQqOBoJBFHXy8kXxHSD8j2VaY1jpAvXhbEIe4C JLqY4HAz39UEJX7nDMyCP9ptLvzq42flUVzKqWEosqn6U2s3JgK38H7yXlKRrJtMo5BB Cjdw== X-Gm-Message-State: AOAM531eIhX2I0dMdcFu33lADVN57KuGYT2JDQlhhWLKuI8mrLsmdup0 ZtN2QQkL9sSt163ORiiV4PgJog== X-Google-Smtp-Source: ABdhPJwNMIksoNnfwnDL94M6cCLC469zciqEj6l/tCwCCWMtveboPOpy0iUcTZQMtdzk16jAFXwx2Q== X-Received: by 2002:a5d:5750:: with SMTP id q16mr25440040wrw.9.1628516321122; Mon, 09 Aug 2021 06:38:41 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id 140sm18782060wmb.43.2021.08.09.06.38.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Aug 2021 06:38:40 -0700 (PDT) Date: Mon, 9 Aug 2021 15:38:38 +0200 From: Daniel Vetter To: Matthew Brost Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Message-ID: References: <20210808180757.81440-1-matthew.brost@intel.com> <20210808180757.81440-3-matthew.brost@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210808180757.81440-3-matthew.brost@intel.com> X-Operating-System: Linux phenom 5.10.0-7-amd64 Subject: Re: [Intel-gfx] [PATCH 2/3] drm/i915/selftests: Fix memory corruption in live_lrc_isolation X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Sun, Aug 08, 2021 at 11:07:56AM -0700, Matthew Brost wrote: > GuC submission has exposed an existing memory corruption in > live_lrc_isolation. We believe that some writes to the watchdog offsets > in the LRC (0x178 & 0x17c) can result in trashing of portions of the > address space. With GuC submission there are additional objects which > can move the context redzone into the space that is trashed. To > workaround this avoid poisoning the watchdog. A Bspec reference here would be good (we can quote anything that's marked for public release, so doesn't have one of the IP markers). Also I think the above should be replicated in condensed form instead of the XXX comment. With those: Acked-by: Daniel Vetter since I definitely have enough clue here for a detailed review. -Daniel > > Signed-off-by: Matthew Brost > --- > drivers/gpu/drm/i915/gt/selftest_lrc.c | 29 +++++++++++++++++++++++++- > 1 file changed, 28 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/gt/selftest_lrc.c b/drivers/gpu/drm/i915/gt/selftest_lrc.c > index b0977a3b699b..6500e9fce8a0 100644 > --- a/drivers/gpu/drm/i915/gt/selftest_lrc.c > +++ b/drivers/gpu/drm/i915/gt/selftest_lrc.c > @@ -1074,6 +1074,32 @@ record_registers(struct intel_context *ce, > goto err_after; > } > > +static u32 safe_offset(u32 offset, u32 reg) > +{ > + /* XXX skip testing of watchdog */ > + if (offset == 0x178 || offset == 0x17c) > + reg = 0; > + > + return reg; > +} > + > +static int get_offset_mask(struct intel_engine_cs *engine) > +{ > + if (GRAPHICS_VER(engine->i915) < 12) > + return 0xfff; > + > + switch (engine->class) { > + default: > + case RENDER_CLASS: > + return 0x07ff; > + case COPY_ENGINE_CLASS: > + return 0x0fff; > + case VIDEO_DECODE_CLASS: > + case VIDEO_ENHANCEMENT_CLASS: > + return 0x3fff; > + } > +} > + > static struct i915_vma *load_context(struct intel_context *ce, u32 poison) > { > struct i915_vma *batch; > @@ -1117,7 +1143,8 @@ static struct i915_vma *load_context(struct intel_context *ce, u32 poison) > len = (len + 1) / 2; > *cs++ = MI_LOAD_REGISTER_IMM(len); > while (len--) { > - *cs++ = hw[dw]; > + *cs++ = safe_offset(hw[dw] & get_offset_mask(ce->engine), > + hw[dw]); > *cs++ = poison; > dw += 2; > } > -- > 2.28.0 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch