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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FF59C7618B for ; Wed, 15 Mar 2023 12:27:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232463AbjCOM1j (ORCPT ); Wed, 15 Mar 2023 08:27:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232519AbjCOM1Q (ORCPT ); Wed, 15 Mar 2023 08:27:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C9FE13771C for ; Wed, 15 Mar 2023 05:26:25 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A9EA361D13 for ; Wed, 15 Mar 2023 12:26:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF42DC433D2; Wed, 15 Mar 2023 12:26:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678883185; bh=87VjF5XzdH+/LkAgNY8ZsKPIgWtTFEPd3GPJfUM5CSQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ggTSfXkUE0sGrOeMokn8EgUYX69CZn0obDGmkPpUEptEBszCvGwYappFxtfx6IHmw pHEwYxG7MY45jh9fRjdt/Et7AoQrfWF6b22QjW5HHRu9TskPasMiziWnP3vsofiv8O iE/jafvM2SS7HTi9rLzJADsG18mNsTj36JcuaVJA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yassine Oudjana , Dmitry Baryshkov , Rob Clark , Sasha Levin Subject: [PATCH 5.15 048/145] drm/msm/a5xx: fix the emptyness check in the preempt code Date: Wed, 15 Mar 2023 13:11:54 +0100 Message-Id: <20230315115740.649308624@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230315115738.951067403@linuxfoundation.org> References: <20230315115738.951067403@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dmitry Baryshkov [ Upstream commit b4fb748f0b734ce1d2e7834998cc599fcbd25d67 ] Quoting Yassine: ring->memptrs->rptr is never updated and stays 0, so the comparison always evaluates to false and get_next_ring always returns ring 0 thinking it isn't empty. Fix this by calling get_rptr() instead of reading rptr directly. Reported-by: Yassine Oudjana Fixes: b1fc2839d2f9 ("drm/msm: Implement preemption for A5XX targets") Signed-off-by: Dmitry Baryshkov Patchwork: https://patchwork.freedesktop.org/patch/522642/ Link: https://lore.kernel.org/r/20230214020956.164473-4-dmitry.baryshkov@linaro.org Signed-off-by: Rob Clark Signed-off-by: Sasha Levin --- drivers/gpu/drm/msm/adreno/a5xx_preempt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/adreno/a5xx_preempt.c b/drivers/gpu/drm/msm/adreno/a5xx_preempt.c index 8abc9a2b114a2..6e326d851ba53 100644 --- a/drivers/gpu/drm/msm/adreno/a5xx_preempt.c +++ b/drivers/gpu/drm/msm/adreno/a5xx_preempt.c @@ -63,7 +63,7 @@ static struct msm_ringbuffer *get_next_ring(struct msm_gpu *gpu) struct msm_ringbuffer *ring = gpu->rb[i]; spin_lock_irqsave(&ring->preempt_lock, flags); - empty = (get_wptr(ring) == ring->memptrs->rptr); + empty = (get_wptr(ring) == gpu->funcs->get_rptr(gpu, ring)); spin_unlock_irqrestore(&ring->preempt_lock, flags); if (!empty) -- 2.39.2