From: Damien Le Moal <damien.lemoal@opensource.wdc.com>
To: Serge Semin <Sergey.Semin@baikalelectronics.ru>,
Hans de Goede <hdegoede@redhat.com>, Jens Axboe <axboe@kernel.dk>
Cc: Serge Semin <fancer.lancer@gmail.com>,
Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>,
Pavel Parkhomenko <Pavel.Parkhomenko@baikalelectronics.ru>,
Rob Herring <robh+dt@kernel.org>,
linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org,
devicetree@vger.kernel.org
Subject: Re: [PATCH 07/21] ata: libahci_platform: Sanity check the DT child nodes number
Date: Thu, 24 Mar 2022 10:40:40 +0900 [thread overview]
Message-ID: <ab7f2a2e-0ca9-ed97-e4ed-bf8ef0ed69a5@opensource.wdc.com> (raw)
In-Reply-To: <20220324001628.13028-8-Sergey.Semin@baikalelectronics.ru>
On 3/24/22 09:16, Serge Semin wrote:
> Having greater than (AHCI_MAX_PORTS = 32) ports detected isn't that
> critical from the further AHCI-platform initialization point of view since
> exceeding the ports upper limit will cause allocating more resources than
> will be used afterwards. But detecting too many child DT-nodes doesn't
> seem right since it's very unlikely to have it on an ordinary platform. In
> accordance with the AHCI specification there can't be more than 32 ports
> implemented at least due to having the CAP.NP field of 4 bits wide and the
> PI register of dword size. Thus if such situation is found the DTB must
> have been corrupted and the data read from it shouldn't be reliable. Let's
> consider that as an erroneous situation and halt further resources
> allocation.
>
> Note it's logically more correct to have the nports set only after the
> initialization value is checked for being sane. So while at it let's make
> sure nports is assigned with a correct value.
>
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> ---
> drivers/ata/libahci_platform.c | 16 +++++++++++-----
> 1 file changed, 11 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
> index 4fb9629c03ab..845042295b97 100644
> --- a/drivers/ata/libahci_platform.c
> +++ b/drivers/ata/libahci_platform.c
> @@ -470,15 +470,21 @@ struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev,
> }
> }
>
> - hpriv->nports = child_nodes = of_get_child_count(dev->of_node);
> -
> /*
> - * If no sub-node was found, we still need to set nports to
> - * one in order to be able to use the
> + * Too many sub-nodes most likely means having something wrong with
> + * firmware. If no sub-node was found, we still need to set nports
> + * to one in order to be able to use the
> * ahci_platform_[en|dis]able_[phys|regulators] functions.
> */
> - if (!child_nodes)
> + child_nodes = of_get_child_count(dev->of_node);
> + if (child_nodes > AHCI_MAX_PORTS) {
> + rc = -EINVAL;
> + goto err_out;
> + } else if (!child_nodes) {
No need for "else" after a return.
> hpriv->nports = 1;
> + } else {
> + hpriv->nports = child_nodes;
> + }
>
> hpriv->phys = devm_kcalloc(dev, hpriv->nports, sizeof(*hpriv->phys), GFP_KERNEL);
> if (!hpriv->phys) {
--
Damien Le Moal
Western Digital Research
next prev parent reply other threads:[~2022-03-24 1:40 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-24 0:16 [PATCH 00/21] ata: ahci: Add DWC/Baikal-T1 AHCI SATA support Serge Semin
2022-03-24 0:16 ` [PATCH 01/21] dt-bindings: ata: sata: Extend number of SATA ports Serge Semin
2022-03-29 8:15 ` Damien Le Moal
2022-04-11 19:25 ` Serge Semin
2022-03-24 0:16 ` [PATCH 02/21] dt-bindings: ata: Convert AHCI-bindings to DT schema Serge Semin
2022-03-28 19:32 ` Rob Herring
2022-04-11 19:34 ` Serge Semin
2022-03-24 0:16 ` [PATCH 03/21] ata: libahci_platform: Explicitly set rc on devres_alloc failure Serge Semin
2022-03-24 0:58 ` Damien Le Moal
2022-03-24 21:37 ` Serge Semin
2022-03-25 1:56 ` Damien Le Moal
2022-04-06 20:03 ` Serge Semin
2022-03-29 8:20 ` Damien Le Moal
2022-03-24 0:16 ` [PATCH 04/21] ata: libahci_platform: Convert to using handy devm-ioremap methods Serge Semin
2022-03-24 1:11 ` Damien Le Moal
2022-04-06 20:42 ` Serge Semin
2022-03-24 0:16 ` [PATCH 05/21] ata: libahci_platform: Convert to using devm bulk clocks API Serge Semin
2022-03-24 1:29 ` Damien Le Moal
2022-04-09 4:59 ` Serge Semin
2022-03-28 22:36 ` kernel test robot
2022-03-28 23:42 ` kernel test robot
2022-03-29 0:03 ` kernel test robot
2022-03-24 0:16 ` [PATCH 06/21] ata: libahci_platform: Add function returning a clock-handle by id Serge Semin
2022-03-24 1:36 ` Damien Le Moal
2022-04-11 6:02 ` Serge Semin
2022-03-24 0:16 ` [PATCH 07/21] ata: libahci_platform: Sanity check the DT child nodes number Serge Semin
2022-03-24 1:40 ` Damien Le Moal [this message]
2022-03-24 8:12 ` Sergey Shtylyov
2022-03-24 8:13 ` Damien Le Moal
2022-04-11 13:10 ` Serge Semin
2022-03-24 0:16 ` [PATCH 08/21] ata: libahci_platform: Parse ports-implemented property in resources getter Serge Semin
2022-03-24 0:16 ` [PATCH 09/21] ata: libahci_platform: Introduce reset assertion/deassertion methods Serge Semin
2022-03-24 1:52 ` Damien Le Moal
2022-04-11 10:57 ` Serge Semin
2022-03-24 0:16 ` [PATCH 10/21] dt-bindings: ata: ahci: Add platform capability properties Serge Semin
2022-03-24 0:16 ` [PATCH 11/21] ata: libahci: Extend port-cmd flags set with port capabilities Serge Semin
2022-03-24 0:16 ` [PATCH 12/21] ata: libahci: Discard redundant force_port_map parameter Serge Semin
2022-03-24 2:05 ` Damien Le Moal
2022-04-11 12:11 ` Serge Semin
2022-04-11 12:25 ` Damien Le Moal
2022-04-11 20:52 ` Serge Semin
2022-04-11 22:48 ` Damien Le Moal
2022-04-12 12:29 ` Serge Semin
2022-03-24 0:16 ` [PATCH 13/21] ata: libahci: Don't read AHCI version twice in the save-config method Serge Semin
2022-03-24 0:16 ` [PATCH 14/21] ata: ahci: Convert __ahci_port_base to accepting hpriv as arguments Serge Semin
2022-03-24 0:16 ` [PATCH 15/21] ata: ahci: Introduce firmware-specific caps initialization Serge Semin
2022-03-24 0:16 ` [PATCH 16/21] dt-bindings: ata: ahci: Add DWC AHCI SATA controller DT schema Serge Semin
2022-04-01 0:06 ` Rob Herring
2022-04-11 20:00 ` Serge Semin
2022-03-24 0:16 ` [PATCH 17/21] ata: ahci: Add DWC AHCI SATA controller support Serge Semin
2022-03-24 2:21 ` Damien Le Moal
2022-04-11 12:41 ` Serge Semin
2022-04-11 13:03 ` Damien Le Moal
2022-04-11 20:41 ` Serge Semin
2022-03-24 0:16 ` [PATCH 18/21] dt-bindings: ata: ahci: Add Baikal-T1 AHCI SATA controller DT schema Serge Semin
2022-03-24 0:16 ` [PATCH 19/21] ata: ahci-dwc: Add platform-specific quirks support Serge Semin
2022-03-24 0:16 ` [PATCH 20/21] ata: ahci-dwc: Add Baikal-T1 AHCI SATA interface support Serge Semin
2022-03-24 0:16 ` [PATCH 21/21] MAINTAINERS: Add maintainers for DWC AHCI SATA driver Serge Semin
2022-03-24 2:17 ` Damien Le Moal
2022-04-11 12:16 ` Serge Semin
2022-03-28 20:06 ` [PATCH 00/21] ata: ahci: Add DWC/Baikal-T1 AHCI SATA support Damien Le Moal
2022-03-29 8:30 ` Damien Le Moal
2022-04-06 19:54 ` Serge Semin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=ab7f2a2e-0ca9-ed97-e4ed-bf8ef0ed69a5@opensource.wdc.com \
--to=damien.lemoal@opensource.wdc.com \
--cc=Alexey.Malahov@baikalelectronics.ru \
--cc=Pavel.Parkhomenko@baikalelectronics.ru \
--cc=Sergey.Semin@baikalelectronics.ru \
--cc=axboe@kernel.dk \
--cc=devicetree@vger.kernel.org \
--cc=fancer.lancer@gmail.com \
--cc=hdegoede@redhat.com \
--cc=linux-ide@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=robh+dt@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).