From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f51.google.com (mail-wm1-f51.google.com [209.85.128.51]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E2AC07C for ; Mon, 23 Jan 2023 12:05:01 +0000 (UTC) Received: by mail-wm1-f51.google.com with SMTP id f25-20020a1c6a19000000b003da221fbf48so8374417wmc.1 for ; Mon, 23 Jan 2023 04:05:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=AMBmfoYya5PgXn4YZDfYUMtggySAK/HwKMtRK6plYP8=; b=aCU33KhsnXFUu/IDemepIQPPaq2LWevf+0j8EsEsDOKcPezA+2LRMTWVj6e7OhCTof 74UbpHP/JGepMFB624HIud3lHqIYZ7ZTbcZ2rbBSRWQnegNZO8yeHwuSr99YMeyeHVJr EyObPon+WO0wm2A7JXtjbdr7TZnPYK9oO3MARvQzG8g4982t7Vwt+KYNKduRnoCFfrng RKugvQXK2NgH85j1FR1B8+7gDZYIKLI5mw25/eIwiaMR37J4PjB06vKn7+MNVR+Sr1BM P3Gdj+KFebm4nRw40LsUcpmUdktHz/xwmbTxbAaTpmgB+Mg01XaT7FpXBTWfQAw74EzU N/Kg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=AMBmfoYya5PgXn4YZDfYUMtggySAK/HwKMtRK6plYP8=; b=x7a9RZy2kgUf+szFz20EhGi6xjZrRSVQIWqZKnlgxzIaEa4UM9a8d6EfZ2QpNIuzkK S+3yayJlKRAfNVcP85X3TIzpQbo+pVlS3PLQihC+fkoT67CNjqC4duq/hVspdFsB3oCx W3sTUGrMDKWM6b/lM2zvp2SiHBpTBUNuHYbpRKPaKNJCAvqwBqCyZ+H+pVkLC38mRctw K+tAu0wDudA4iBqObd3GMiixmyMi79ckv/QDRoofAdfSX6R4ahBMiv3DhFuIa3vqdnzE RjgItosKNVkQisnpYWsl0g/D5USaqO0e5tozEkZ2Ij5fAcUogVnRrGHDb/3w/cchPuAm CdTg== X-Gm-Message-State: AFqh2kridhViPAU51IZt41uM/UZoxgw8GDvrl6uTcpfaWqkno2CXQzG/ l2UrDRZtLSVGt1OgJDqA5Ao= X-Google-Smtp-Source: AMrXdXtxDoap+d7zX3hP2ldTumD2iqOsEVcDveuuO4JcRCXk81Ogw0HNRqLo4TXJHw9H9gLnIDeBwg== X-Received: by 2002:a05:600c:4e4b:b0:3db:2e6d:9f79 with SMTP id e11-20020a05600c4e4b00b003db2e6d9f79mr12360642wmq.39.1674475500256; Mon, 23 Jan 2023 04:05:00 -0800 (PST) Received: from localhost ([102.36.222.112]) by smtp.gmail.com with ESMTPSA id o21-20020a05600c4fd500b003c6f8d30e40sm11642757wmq.31.2023.01.23.04.04.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Jan 2023 04:04:59 -0800 (PST) Date: Mon, 23 Jan 2023 15:04:56 +0300 From: Dan Carpenter To: Christian Hewitt Cc: Neil Armstrong , Mauro Carvalho Chehab , Greg Kroah-Hartman , Kevin Hilman , Jerome Brunet , Martin Blumenstingl , linux-media@vger.kernel.org, linux-amlogic@lists.infradead.org, linux-staging@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Neil Armstrong Subject: Re: [PATCH] media: meson: vdec: esparser: check parsing state with hardware write pointer Message-ID: References: <20230123094300.2816812-1-christianshewitt@gmail.com> Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230123094300.2816812-1-christianshewitt@gmail.com> On Mon, Jan 23, 2023 at 09:43:00AM +0000, Christian Hewitt wrote: > From: Neil Armstrong > > Also check the hardware write pointer to check if ES Parser has stalled. > Presumably this is something which has happens in real life? Say a user has this hardware and is wondering if this patch fixes their bug, what does this bug look like to them? Please add a Fixes tag. > Signed-off-by: Neil Armstrong > Signed-off-by: Christian Hewitt > --- > drivers/staging/media/meson/vdec/esparser.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/drivers/staging/media/meson/vdec/esparser.c b/drivers/staging/media/meson/vdec/esparser.c > index df5956c6141d..41b705f999b2 100644 > --- a/drivers/staging/media/meson/vdec/esparser.c > +++ b/drivers/staging/media/meson/vdec/esparser.c > @@ -300,6 +300,7 @@ esparser_queue(struct amvdec_session *sess, struct vb2_v4l2_buffer *vbuf) > u32 num_dst_bufs = 0; > u32 offset; > u32 pad_size; > + u32 wp, wp2; > > /* > * When max ref frame is held by VP9, this should be -= 3 to prevent a > @@ -354,15 +355,21 @@ esparser_queue(struct amvdec_session *sess, struct vb2_v4l2_buffer *vbuf) > } > > pad_size = esparser_pad_start_code(core, vb, payload_size); > + wp = amvdec_read_parser(core, PARSER_VIDEO_WP); > ret = esparser_write_data(core, phy, payload_size + pad_size); > + wp2 = amvdec_read_parser(core, PARSER_VIDEO_WP); > Why is check not done inside the esparser_write_data() function? It really feels like doing a write where nothing happens should be a bug for both callers... The esparser_write_data() function returns > 0 on success, 0 on timeout (I guess timeout is an error-ish) and negative if the user presses CTR-C. There are no comments to explain the unusual returns. Could we clean this up so it just returns negatives on error and zero on success or if not then let's add a comment explaining what's going on? > if (ret <= 0) { > - dev_warn(core->dev, "esparser: input parsing error\n"); > - amvdec_remove_ts(sess, vb->timestamp); > - v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR); > amvdec_write_parser(core, PARSER_FETCH_CMD, 0); > > - return 0; > + if (ret < 0 || wp2 == wp) { So in this patch if there is a timeout but something was written then that's kind of a success path? regards, dan carpenter > + dev_err(core->dev, "esparser: input parsing error ret %d (%x <=> %x)\n", > + ret, wp, wp2); > + amvdec_remove_ts(sess, vb->timestamp); > + v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_ERROR); > + > + return 0; > + } > } > > atomic_inc(&sess->esparser_queued_bufs);