From: Keith Busch <kbusch@kernel.org>
To: Matthew Wood <thepacketgeek@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
Nikita Vetoshkin <nekto0n@meta.com>
Subject: Re: [PATCH 4/5] PCI/sysfs: Use user config accessors for link attributes
Date: Mon, 26 Oct 2026 09:21:28 -0600 [thread overview]
Message-ID: <at9v-M0sb9dSRDEt@kbusch-mbp> (raw)
In-Reply-To: <20261025000836.58294-5-thepacketgeek@gmail.com>
On Sat, Oct 24, 2026 at 05:08:32PM -0700, Matthew Wood wrote:
> max_link_width, current_link_speed and current_link_width read the PCIe
> Link Capabilities and Link Status registers with the kernel config
> accessors. Those don't check block_cfg_access so a read that races
> with a reset goes to the device mid-reset and can fail or return a bogus
> value.
>
> Use pcie_capability_user_read_{word,dword}() instead so the read waits for
> any pci_cfg_access_lock() holder (e.g. pci_reset_function()) to finish. For
> max_link_width, this means inlining the pcie_get_width_cap() logic
> instead of creating an additional helper with this single calling location.
Looks good.
Reviewed-by: Keith Busch <kbusch@kernel.org>
next prev parent reply other threads:[~2026-10-26 15:21 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-25 0:08 [PATCH 0/5] PCI/sysfs: Wait for config access lock in sysfs attributes Matthew Wood
2026-10-25 0:08 ` [PATCH 1/5] PCI: Add disconnected device checks to user config reads Matthew Wood
2026-10-25 0:08 ` [PATCH 2/5] PCI/sysfs: Use user config accessors for bus number attributes Matthew Wood
2026-10-26 15:00 ` Keith Busch
2026-10-25 0:08 ` [PATCH 3/5] PCI: Add pcie_capability_user_read_{word,dword}() Matthew Wood
2026-10-26 15:20 ` Keith Busch
2026-10-25 0:08 ` [PATCH 4/5] PCI/sysfs: Use user config accessors for link attributes Matthew Wood
2026-10-26 15:21 ` Keith Busch [this message]
2026-10-25 0:08 ` [PATCH 5/5] PCI/sysfs: Use user config accessors for serial_number Matthew Wood
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=at9v-M0sb9dSRDEt@kbusch-mbp \
--to=kbusch@kernel.org \
--cc=bhelgaas@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=nekto0n@meta.com \
--cc=thepacketgeek@gmail.com \
/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
all inboxes | Powered by JetHome®