From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CC6DE15B125; Mon, 19 Aug 2024 11:01:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724065315; cv=none; b=mByPiBsiaPrlYwI6lkySSFluNjbSmPuDnIeUWhBE7qiUeA1WZeUlf27nrdhZwHIkD5r7Pyr/qgFj4zO6j1FFXBVmXKnuToW6hArTS1khf33o3LIszw4PQDcpPvYwSwA0TqqJFRQZRlWLGK/rgNVxOBD5RqCmfGIi+niGJx0lFGQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724065315; c=relaxed/simple; bh=RKjobX7+cX15lxVhF/xFB6okKKom6P4UVqu82yq3zr0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=PJKN4qMfOjvh+FDhqmAISuJ6oZOPDtb6AxlumPHfRgU4DMDTFZCoZHTd3q/wcvOvleRf8utOhwj5h6nx6qy//NK1FydrBXuXZ65BDtjk6JOTmk/hhCDKVF7jnBWrtGZKfGI1qHp6dIMboxZdTwGwQ0zWkZkDhUXeGGZrVgXURGI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S+uG3ule; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="S+uG3ule" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 616A0C32782; Mon, 19 Aug 2024 11:01:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724065315; bh=RKjobX7+cX15lxVhF/xFB6okKKom6P4UVqu82yq3zr0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=S+uG3uleWXjeur9lX+9XwXwxgSHehaXUwK+vFzMctal4HzHStOMls2jxPEzk0Wjfo Bu/h9UZC0pCV6jNe5Bg1rHMUO8gI/M/5Sbt2+B40OcTSu8N5wzCYg1qQKGFtqvVkUq QmWI8CXEu/xi4bPLtz2PRSnXB7VeXD/RsJ8A7ohg03DWcpMEDbEFNquRY2BcrxfGEe TbLGt2xeH91Lv1R73kGteOt/rnUy6Etc2p/1FmRHxdxp/pFcM/4sryD40sFRa5Kqr9 flmplLT4BzvhyUrZQbpk4w94J1Bapnux9sHIHeqxHWXP045OHXcRJcDhPmjoSFIx41 qFykD+krjPjtg== Message-ID: <737ad178-1198-4103-b1ee-46a67ecf12e4@kernel.org> Date: Mon, 19 Aug 2024 20:01:53 +0900 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH] ata: pata_macio: Use WARN instead of BUG To: Michael Ellerman , cassel@kernel.org Cc: linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, hch@lst.de, linux-ppc@kolla.no, vidra@ufal.mff.cuni.cz References: <20240819101913.489513-1-mpe@ellerman.id.au> From: Damien Le Moal Content-Language: en-US Organization: Western Digital Research In-Reply-To: <20240819101913.489513-1-mpe@ellerman.id.au> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/19/24 19:19, Michael Ellerman wrote: > The overflow/underflow conditions in pata_macio_qc_prep() should never > happen. But if they do there's no need to kill the system entirely, a > WARN and failing the IO request should be sufficient and might allow the > system to keep running. > > Signed-off-by: Michael Ellerman > --- > drivers/ata/pata_macio.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > Not sure if AC_ERR_OTHER is the right error code to use? Given that this would trigger if the command split has is buggy, I think that AC_ERR_SYSTEM would be better. Can you resend with the change and no "RFC" ? > > diff --git a/drivers/ata/pata_macio.c b/drivers/ata/pata_macio.c > index eaffa510de49..552e3ac0d391 100644 > --- a/drivers/ata/pata_macio.c > +++ b/drivers/ata/pata_macio.c > @@ -554,7 +554,8 @@ static enum ata_completion_errors pata_macio_qc_prep(struct ata_queued_cmd *qc) > > while (sg_len) { > /* table overflow should never happen */ > - BUG_ON (pi++ >= MAX_DCMDS); > + if (WARN_ON_ONCE(pi >= MAX_DCMDS)) > + return AC_ERR_OTHER; > > len = (sg_len < MAX_DBDMA_SEG) ? sg_len : MAX_DBDMA_SEG; > table->command = cpu_to_le16(write ? OUTPUT_MORE: INPUT_MORE); > @@ -566,11 +567,13 @@ static enum ata_completion_errors pata_macio_qc_prep(struct ata_queued_cmd *qc) > addr += len; > sg_len -= len; > ++table; > + ++pi; > } > } > > /* Should never happen according to Tejun */ > - BUG_ON(!pi); > + if (WARN_ON_ONCE(!pi)) > + return AC_ERR_OTHER; > > /* Convert the last command to an input/output */ > table--; -- Damien Le Moal Western Digital Research