From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=204.191.154.188 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794535413; b=jyG+omOJ+RWOzwHF28Uh/mmrEkjmmjgeVRdZyVMvl3c/PJCHSQdq8ZpYSFLXS6L9UqWB rPLz20ILZ/pYa6Etj04TariTOlvUqsVskLyfQ+ONPGbgyRJhsQiz07vG1skEwWpLC68UG L6hWSSTnk0n5YocuXQY37jchFoV1iA93x08X3VfqE7pSRA8WIed6Wn+5HHypABxwhWzlf w4oD5Gs0BhJyRa9n22vPTBo8Unhlt/Mq5NmD2iVBCKtUVrBKB4V6Yfdy3/yE/Xm3lP3s3 7cWEwY9fq/mJEkKOQ0+R+BcOqvFihvcaBYU4lvY//qUk6SLn3mawVm5bKm0JSsRVkxg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794535413; h=DMARC-Filter:DKIM-Signature:Received:Message-ID:Date:MIME-Version: User-Agent:To:Cc:References:From:Content-Language:In-Reply-To: Content-Type:Content-Transfer-Encoding:X-SA-Exim-Connect-IP: X-SA-Exim-Rcpt-To:X-SA-Exim-Mail-From:X-Spam-Checker-Version: X-Spam-Level:X-Spam-Status:Subject:X-SA-Exim-Version: X-SA-Exim-Scanned; bh=WGp60iebrceeykw5z9ks0STNk2un0gKAwGb3SyzUjH0=; b=Suc+o41ff4SBYEN1GYQqNnIsRaqK/Rv1c4NISzuRREnE9kHHgB8BCyWczArYI6o1sTGg 2CufY4bURV9MrmnxKpyicUPOKwXB9WKKOCkJgJgI1sYTnrNkNOkwDSZtwMuOxsT2equxa Bychh8PODWb07XUXsO5cInLANuiYyecJEThUGYhfwc3F4Lk/iuAgkaE4QjyP4yJmIYtEA b96lzKazBC2cH6AEUKmUzhTi1M0Q0ExnDNAKgOVbc7894EadMTZy3xq7y2Henh8XYqlXv psZXJApU7DRylYoMGuM2lizgNOsCU5OWVv+DFn70kcUY9OAWQrEDQbcQk5G8NsDT0gA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=deltatee.com; spf=pass smtp.mailfrom=deltatee.com; dkim=pass header.d=deltatee.com header.i=@deltatee.com header.a=rsa-sha256 header.s=20200525 header.b=I1cJaawp; arc=none smtp.remote-ip=204.191.154.188 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B6639606A321; Fri, 13 Nov 2026 02:03:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B6639606A321 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=deltatee.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=deltatee.com header.i=@deltatee.com header.a=rsa-sha256 header.s=20200525 header.b=I1cJaawp DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:In-Reply-To:From:References:Cc:To: MIME-Version:Date:Message-ID:content-disposition; bh=WGp60iebrceeykw5z9ks0STNk2un0gKAwGb3SyzUjH0=; b=I1cJaawpaQh/eqik9UCP6jlcV+ +ff2nbpYP/YhCSCiPSviiivDaU1gSLMMWauYCgv5Oluq4obD8slgaHK48V5Jgj2/QAXFJajhUcXRH WgH3787xsl1fWBLE/qO5uqxVUXAUMgzK6WuZyA5HknUUaekzaBrmb729wRbktI6WljU95iQA+YSWC NlA0cONSDNFzMBE5+vxYyMnxyQ3IobzCgntDbcklSx8s7he2B/vXKl7sXJCP1vXJAOdbu/leNFdkZ k1iX0hBRmB6dO93Kcb9vc15bSJy5YoVJGrUkuLMCB1cFB6+Znk6j4jtKNltZ9NRjHYq/qSqDj1iN4 sWecGjJA==; Received: from [104.157.31.28] (helo=[192.168.1.251]) by ale.deltatee.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.98.2) (envelope-from ) id 1xRgdP-00000002R98-2ZLr; Thu, 12 Nov 2026 20:03:24 -0600 Message-ID: <1a07c926-d710-4922-a4a1-be235df7c74c@deltatee.com> Date: Thu, 12 Nov 2026 20:02:53 -0600 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Ben Cressey , Jonathan Corbet , Shuah Khan , Randy Dunlap , Bjorn Helgaas Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, =?UTF-8?Q?Krzysztof_Wilczy=C5=84ski?= , Alex Williamson , Wei Wang , Jason Gunthorpe , "Anthony Vardaro (Anthropic)" References: <20261111-pci-idpath-selector-v2-1-83ea668e38f0@cressey.dev> From: Logan Gunthorpe Content-Language: en-CA In-Reply-To: <20261111-pci-idpath-selector-v2-1-83ea668e38f0@cressey.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 104.157.31.28 X-SA-Exim-Rcpt-To: ben@cressey.dev, corbet@lwn.net, skhan@linuxfoundation.org, rdunlap@infradead.org, bhelgaas@google.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, kwilczynski@kernel.org, alex@shazbot.org, wei.w.wang@hotmail.com, jgg@ziepe.ca, me@anthonyvardaro.com X-SA-Exim-Mail-From: logang@deltatee.com X-Spam-Level: Subject: Re: [PATCH v2] PCI: Add ID@path device format for pci= parameters X-SA-Exim-Version: 4.2.1 (built Sun, 23 Feb 2025 07:57:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) On 2026-11-11 5:36 p.m., Ben Cressey wrote: > The grammar shared by pci=resource_alignment=, > pci=disable_acs_redir= and pci=config_acs= names a device either by > address, with an optional path, or by ID. When one command line serves > more than one platform, neither form limits an entry to the intended > device: an address applies to whatever occupies it on each platform, and > an ID applies to every instance, such as all Downstream Ports of a > switch rather than the one that needs different ACS settings. > > Accept pci::[::]@, where > is the address format, and match only when both halves match. An > entry written for one platform is then inert on another where that > address holds a different device. For example, > > pci=config_acs=xx111x1@pci:10b5:8749@0000:80:02.0/00.0/08.0 > > configures ACS on the Downstream Port at that path only if it is a > PEX 8749 port. > > The path goes last since pci_dev_str_match_path() consumes up to the > next ';'. The IDs are compared first, and the path is parsed only for a > device that matches them. The @ and @ prefixes of > resource_alignment and config_acs are stripped before > pci_dev_str_match() is called, so the callers are unchanged. > > Suggested-by: Wei Wang > Signed-off-by: Ben Cressey Looks pretty straightforward and the reasoning all makes sense to me. Reviewed-by: Logan Gunthorpe