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 208A633C5; Wed, 26 Jun 2024 06:22:00 +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=1719382921; cv=none; b=lfZCUhSptFrJNen6hSo8NdOAC7Git/QeH6pl+xczHDm5Vg2fKbihuB9VyVbkdhj8hO+KM8tUeYVWpjlFji0N4YaPM3b7yVPT8xg4V//gH9S4EjhJdbba6CTK9XQE4v1vCPZERKme7eO/eMAVb/d4ezJhSLQnfAkc8krhRRlcHJE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719382921; c=relaxed/simple; bh=1Yqx0WkL7pvMSlUmi9moTnQle6ioWFoYo3zI/ISLmP8=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=tzPC0wZTqx7BXj+UgEc3TphX0yXzl2z/2oEDFgMqq54tKEY9vfMbdWJVuh40HWJngBbAijkoNMw3Pwp9fAQZ63p0qcCEY/d9oNrZWx+xOLZScLYYi54w+oeKnM5oFtwYT15yASuUGVXJTEICXfyMZkyP14VUwKl7I120kMDMvjs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VlQGZrKQ; 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="VlQGZrKQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8ED0EC2BD10; Wed, 26 Jun 2024 06:21:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1719382920; bh=1Yqx0WkL7pvMSlUmi9moTnQle6ioWFoYo3zI/ISLmP8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=VlQGZrKQgu05rMOK6YmjwjYQdiGA5F0WnTMfTUe7Fr58UZDYzil5gT+YvXEQf9Qif 545W0ANA2sQtaPGxw0pBXkW4NVBb3BDDsX5ACVdDWxQWoyGiW9UWnKvQinPJtoC/s+ sbIDhIgvFz3upWBx1m0RPHZRdP/HoIqKfT+CM2ksxQIcc8EFnVEHzHn3M5xhxPyCN7 8l25d1sDn4vbKi3x6eeS30IH7CZNkq36g9UeZlCD3CZezK281XrlORD9jG3DhFknin K3uV0/KOS2YX8IoAhBqGdDMmf9IvNLZUO24Z1Mmuvq05C4UAENCPmjHHc0V2JYaPmY J5C1hb8fbVmJA== Message-ID: Date: Wed, 26 Jun 2024 15:21:58 +0900 Precedence: bulk X-Mailing-List: linux-ide@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 6/6] ata: libata-scsi: Check ATA_QCFLAG_RTF_FILLED before using result_tf To: Igor Pylypiv , Hannes Reinecke Cc: Niklas Cassel , Tejun Heo , "Martin K. Petersen" , Jason Yan , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org References: <20240624221211.2593736-1-ipylypiv@google.com> <20240624221211.2593736-7-ipylypiv@google.com> <7d085940-2ad1-4f44-83bb-33d852e80da0@suse.de> From: Damien Le Moal Content-Language: en-US Organization: Western Digital Research In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 6/26/24 09:30, Igor Pylypiv wrote: > On Tue, Jun 25, 2024 at 08:26:59AM +0200, Hannes Reinecke wrote: >> On 6/25/24 00:12, Igor Pylypiv wrote: >>> qc->result_tf contents are only valid when the ATA_QCFLAG_RTF_FILLED flag >>> is set. The ATA_QCFLAG_RTF_FILLED flag should be always set for commands >>> that failed or for commands that have the ATA_QCFLAG_RESULT_TF flag set. >>> >>> For ATA errors and ATA PASS-THROUGH commands the ATA_QCFLAG_RTF_FILLED >>> flag should be always set. Added WARN_ON_ONCE() checks to generate >>> a warning when ATA_QCFLAG_RTF_FILLED is not set and libata needs to >>> generate sense data. >>> >>> Signed-off-by: Igor Pylypiv >>> --- >>> drivers/ata/libata-scsi.c | 10 ++++++++++ >>> 1 file changed, 10 insertions(+) >>> >>> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c >>> index e5669a296d81..7a8a08692ce9 100644 >>> --- a/drivers/ata/libata-scsi.c >>> +++ b/drivers/ata/libata-scsi.c >>> @@ -246,6 +246,9 @@ static void ata_scsi_set_passthru_sense_fields(struct ata_queued_cmd *qc) >>> struct ata_taskfile *tf = &qc->result_tf; >>> unsigned char *sb = cmd->sense_buffer; >>> >>> + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED))) >>> + return; >>> + >>> if ((sb[0] & 0x7f) >= 0x72) { >>> unsigned char *desc; >>> u8 len; >>> @@ -928,6 +931,9 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc) >>> unsigned char *sb = cmd->sense_buffer; >>> u8 sense_key, asc, ascq; >>> + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED))) >>> + return; >>> + >>> /* >>> * Use ata_to_sense_error() to map status register bits >>> * onto sense key, asc & ascq. >>> @@ -971,6 +977,10 @@ static void ata_gen_ata_sense(struct ata_queued_cmd *qc) >>> ata_scsi_set_sense(dev, cmd, NOT_READY, 0x04, 0x21); >>> return; >>> } >>> + >>> + if (WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_RTF_FILLED))) >>> + return; >>> + >>> /* Use ata_to_sense_error() to map status register bits >>> * onto sense key, asc & ascq. >>> */ >> >> Hmm. Not sure if we really need the WARN_ON() here or whether a simple >> logging message wouldn't be sufficient; after all, we continue fine here. >> > > My worry about adding a simple log statement is that it might cause a log > spam if things go wrong for some reason. > > This code is more like a "this should never happen" comment and we always > expect ATA_QCFLAG_RTF_FILLED to be present when generating sense data > based on ATA registers. > > If WARN_ON_ONCE() is too much for this case I guess we can just remove it > and silently return? what about ata_dev_dbg() or ata_port_dbg() ? No message spamming by default and if problems are detected, they can be turned on to figure out what is going on. > > Damien, Niklas, what are your thoughts on this? > > Thanks, > Igor > >> Cheers, >> >> Hannes >> -- >> Dr. Hannes Reinecke Kernel Storage Architect >> hare@suse.de +49 911 74053 688 >> SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg >> HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich >> -- Damien Le Moal Western Digital Research