Linux PCI subsystem development
 help / color / mirror / Atom feed
From: sashiko-bot@kernel.org
To: "Mohamad Raizudeen" <raizudeen.kerneldev@gmail.com>
Cc: linux-pci@vger.kernel.org
Subject: Re: [PATCH v2] PCI: Fix 32-bit config write in Intel RP MPC ACS quirk
Date: Thu, 23 Jul 2026 17:18:15 +0000	[thread overview]
Message-ID: <20260723171834.17FFF1F000E9@smtp.kernel.org> (raw)
In-Reply-To: <20260723171203.4892-1-raizudeen.kerneldev@gmail.com>

> The pci_quirk_enable_intel_rp_mpc_acs() reads a 32 bit DWORD from the
> MPC register, sets bit 26 (INTEL_MPC_REG_IRBNCE), but it writes it back
> using pci_write_config_word().
> 
> Because bit 26 resides in the upper 16 bits of the 32 bit register, a 16
> bit write to offset 0xd8 completely drops the newly set bit. The quirk
> logs that it is enabling IRBNCE, but the hardware never actually
> receives the command.
> 
> Fix this by using pci_write_config_dword() to ensure the full 32 bit
> value is written back to the hardware.
> 
> Fixes: d99321b63b1f ("PCI: Enable quirks for PCIe ACS on Intel PCH root ports")
> Signed-off-by: Mohamad Raizudeen <raizudeen.kerneldev@gmail.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260723171203.4892-1-raizudeen.kerneldev@gmail.com?part=1


      reply	other threads:[~2026-07-23 17:18 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-23 17:12 [PATCH v2] PCI: Fix 32-bit config write in Intel RP MPC ACS quirk Mohamad Raizudeen
2026-07-23 17:18 ` sashiko-bot [this message]

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=20260723171834.17FFF1F000E9@smtp.kernel.org \
    --to=sashiko-bot@kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=raizudeen.kerneldev@gmail.com \
    --cc=sashiko-reviews@lists.linux.dev \
    /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