From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 57096361970; Tue, 4 Aug 2026 20:03:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=204.191.154.188 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785873800; cv=none; b=p+YNlQrnhfexxFgIMDmrh5APGiI+GIBsYKid6wUpUsGlfArDquZ6v5pAxC+BbIhs6+gWM5VGOc61YLZHTsFFOc6jltUyfz8MxIO++r0mHOLZr1e9Hi5q4+W7+lJ8KyitdNqsMboAknJVUOJhWWCSDulhuM0+54rL8Y0URRKrQBk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785873800; c=relaxed/simple; bh=EKl4VXD2TveRtNvkzzY0QLOs6hT9Swht+AhBNmDHQt4=; h=Message-ID:Date:MIME-Version:To:Cc:References:From:In-Reply-To: Content-Type:Subject; b=iznSgh9wsYKIvVe7ScXB901bmMZr8+rIObftX5gKDZ4oOWBG6LDiU+24amB37iAs/jH4rlI6l5UwjtYdpRuNdx2GzSPnEX4ITi4ZASR3KduIIGNAVAD5TQL3iI8ELS2Dm3ZGOLAGSS7t/+WnhL27l+0d1Jf8WIqCQFg03oqDs1Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=deltatee.com; spf=pass smtp.mailfrom=deltatee.com; dkim=pass (2048-bit key) header.d=deltatee.com header.i=@deltatee.com header.b=gmtSJEad; arc=none smtp.client-ip=204.191.154.188 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) header.d=deltatee.com header.i=@deltatee.com header.b="gmtSJEad" 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=fXoKWej1UuOX16jfhGM2WAZHIRZZk8cB3V/1ULcgatA=; b=gmtSJEadokGFnG8BX5mTFCBbdO 1e+v1x5/AO+DDGtiKayh79RMjVkjWlqkP0IQDDk9JJMIMpFCR44UZx54rtEwo+E1AYhTebTiWkXuj ZVh5RO4UhjHRpWtyhKjALoLMqQGwET/18Td88wfJAI1yvw4Ge4rME5OxZMpdnbNS0/JEaJj09d+0w TAZz6kKlvXS5XiK34EW8I7Dg1XHPf8WlZ3ECebrtzbB2BOJx3L1TKWQbyIJL3Iw8Uf8aV6RaNKny9 hi7wwoUaGpBruJ4acqyfTWs2fvq6y85C36fkqL37GuIyv+oMza2TPYWagKwDLg5Y4WNQnY+PqzMVJ 20dKILDA==; Received: from guinness.priv.deltatee.com ([172.16.1.162]) by ale.deltatee.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.98.2) (envelope-from ) id 1wrLM5-0000000016x-13yw; Tue, 04 Aug 2026 14:03:17 -0600 Message-ID: Date: Tue, 4 Aug 2026 14:03:16 -0600 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Leon Romanovsky , Bjorn Helgaas , Jonathan Corbet , Shuah Khan , Alex Williamson Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org References: <20260802-fix-p2p-acs-v1-0-a7c5eb64fff6@nvidia.com> <20260802-fix-p2p-acs-v1-4-a7c5eb64fff6@nvidia.com> Content-Language: en-CA From: Logan Gunthorpe In-Reply-To: <20260802-fix-p2p-acs-v1-4-a7c5eb64fff6@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.162 X-SA-Exim-Rcpt-To: leon@kernel.org, bhelgaas@google.com, corbet@lwn.net, skhan@linuxfoundation.org, alex@shazbot.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org X-SA-Exim-Mail-From: logang@deltatee.com X-Spam-Level: Subject: Re: [PATCH 04/13] PCI: Account for Direct Translated P2P in ACS isolation checks 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 2026-08-02 09:09, Leon Romanovsky wrote: > From: Leon Romanovsky > > PCIe r7.0, sec 6.12.3: > > peer-to-peer Memory Requests whose Address Type (AT) field indicates a > Translated address must be routed to the peer Port/Function without > redirection, regardless of ACS P2P Request Redirect and ACS P2P Egress > Control settings. > > Request Redirect therefore does not isolate devices below a Port with > ACS Direct Translated P2P enabled. > > Sec 6.12.1.1 makes such a Request an ACS Violation once Translation > Blocking is enabled, and that error "must take precedence over ... ACS > P2P control mechanisms". Report isolation only in that case. Without > Translation Blocking, devices below such a Port now share an IOMMU > group. > > Fixes: ad805758c0eb ("PCI: add ACS validation utility") > Signed-off-by: Leon Romanovsky LGTM Reviewed-by: Logan Gunthorpe