From: Leon Romanovsky <leon@kernel.org>
To: Logan Gunthorpe <logang@deltatee.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>,
Jonathan Corbet <corbet@lwn.net>,
Shuah Khan <skhan@linuxfoundation.org>,
Alex Williamson <alex@shazbot.org>,
linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-doc@vger.kernel.org
Subject: Re: [PATCH 09/13] PCI/P2PDMA: Document ACS egress control handling
Date: Wed, 5 Aug 2026 12:02:39 +0300 [thread overview]
Message-ID: <20260805090239.GB23431@unreal> (raw)
In-Reply-To: <748b76b4-0a07-4145-87e2-9991412f0401@deltatee.com>
On Tue, Aug 04, 2026 at 04:01:41PM -0600, Logan Gunthorpe wrote:
>
>
> On 2026-08-02 09:09, Leon Romanovsky wrote:
> > +ACS P2P Egress Control does not by itself force a transaction upstream. A
> > +clear Egress Control Vector bit for the peer port permits direct routing; a
> > +set bit redirects the request upstream when P2P Request Redirect is enabled.
> > +When Request Redirect is disabled, a set vector bit causes an ACS Violation
> > +instead. The kernel evaluates these controls together and routes P2P DMA
> > +through the host bridge when the direct path is blocked or cannot be
> > +determined.
>
> One small nit here: I'd put commas around "by itself" to make it read a
> little easier:
>
> "ACS P2P Egress Control does not, by itself, force a transaction..."
>
> Other than that:
>
> Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Thanks for the review. I understand the effort involved and truly
appreciate it.
next prev parent reply other threads:[~2026-08-05 9:02 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-08-02 15:09 [PATCH 00/13] PCI/P2PDMA: Fix ACS egress control handling Leon Romanovsky
2026-08-02 15:09 ` [PATCH 01/13] PCI/P2PDMA: Safely terminate ACS redirect lists Leon Romanovsky
2026-08-04 19:49 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 02/13] PCI/P2PDMA: Report ACS ports when the paths share no upstream bridge Leon Romanovsky
2026-08-04 19:52 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 03/13] PCI/P2PDMA: Document the Address Type assumption Leon Romanovsky
2026-08-04 19:55 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 04/13] PCI: Account for Direct Translated P2P in ACS isolation checks Leon Romanovsky
2026-08-04 20:03 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 05/13] PCI: Add ACS egress control vector accessor Leon Romanovsky
2026-08-04 21:55 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 06/13] PCI: Account for ACS egress control in isolation checks Leon Romanovsky
2026-08-04 21:55 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 07/13] PCI/P2PDMA: Derive peer-to-peer routing from ACS control bits Leon Romanovsky
2026-08-04 21:55 ` Logan Gunthorpe
2026-08-04 21:58 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 08/13] PCI/P2PDMA: Honor ACS egress control vectors Leon Romanovsky
2026-08-04 21:56 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 09/13] PCI/P2PDMA: Document ACS egress control handling Leon Romanovsky
2026-08-04 22:01 ` Logan Gunthorpe
2026-08-05 9:02 ` Leon Romanovsky [this message]
2026-08-02 15:09 ` [PATCH 10/13] PCI/P2PDMA: Extract pure ACS routing decision helpers Leon Romanovsky
2026-08-04 22:07 ` Logan Gunthorpe
2026-08-05 9:06 ` Leon Romanovsky
2026-08-02 15:09 ` [PATCH 11/13] PCI/P2PDMA: Add KUnit tests for ACS routing decisions Leon Romanovsky
2026-08-04 22:37 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 12/13] PCI/P2PDMA: Add KUnit coverage for the ACS P2P routing walk Leon Romanovsky
2026-08-04 22:37 ` Logan Gunthorpe
2026-08-02 15:09 ` [PATCH 13/13] PCI: Add KUnit coverage for ACS isolation checks Leon Romanovsky
2026-08-04 22:38 ` Logan Gunthorpe
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