From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f170.google.com (mail-pl1-f170.google.com [209.85.214.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5CD6235E1A5 for ; Mon, 24 Aug 2026 13:43:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787578996; cv=none; b=Bpm+YdFpWrRfMm1g1wPw2IYwUFIgGoxo3nJUwiu0beWEjjkQAYWz/baW2FzCvDl1Wh5TkkR+Wb3UfY/n7lJx3TrYxr6nNhIti6oohhLeu2C27xh/962YZfXqVEt+HRCKTmqsBN25Vkp+pKYJ2Ewd9LhYLahZ4qJL4l2i3jNk7Gw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787578996; c=relaxed/simple; bh=t5Dnvpr75mSiRYxvcDa5qq9C4XOlypp3dsvqxmbZkvk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VQJPgzEAGx/fEpfWZgsWupuWqcANmjVuVQQoj4+5+/kHJrpR7nKTPn1xG1839c7BuunM02NtVFFaCfNgJmMIVfGZ/tddktYrd3iogtjyBGgbJ96/zuzUHSZMJLXUCCBNYyj6pgJ/EaZY55Asvt3JZu5VefzSIoBavD+hxJF44jk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=ckDW2Jo3; arc=none smtp.client-ip=209.85.214.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ckDW2Jo3" Received: by mail-pl1-f170.google.com with SMTP id d9443c01a7336-2cede6375caso165095ad.0 for ; Mon, 24 Aug 2026 06:43:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1787578988; x=1788183788; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=vCw4dJI8ZifsRp4I78bl5/NA1XA7Yj79m2p41cLSM34=; b=ckDW2Jo3U3yFdou3e5NiXT7pndBkVD7Wu4uHHJ1VKvoACfXivDdSxfZtDfkha4MAgd hwFwbuE7mNWsPQPvh8ZO94pjFCEY1HCr3Ge95WrGVWibhVdpZroV0SzLncFaGk4xfojE CoR9fDq1i3nBufWmuikM2iz8CbrODqGpePGyb5kZ6cNPVN1CzPNCCObtz25TUcLYPr9w SBd1eFm/gGkOMOlX3WrKn0Mq6EM8M6AZ1suMjaNWKS4QQE9XPXOdVK+1IBywY5pwFhm2 UgTb+DjaAlmaOF2X62V0tuLNJmgvbABZkrGBCSZ2TmRQ7Myl9xBfewBCTysCZRxYZlH4 aVcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787578988; x=1788183788; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=vCw4dJI8ZifsRp4I78bl5/NA1XA7Yj79m2p41cLSM34=; b=UMYQzQd/N64Y7aMnHE0Tf2RC3rRXa9UFipNT3q/X0pAYJOhtorAb5ox9rquIXSs8iu 7Bx8KrXp6nKktJaCpbbatRdvHnFIy3FpqJqwc+nN2J5AlmMX2cBli6p6stJ5bhEM/PFz xY8ZSqN5/FEFxF+xCOJf/1WgZUiX7y0qG+nP/t9vke0s7OgO7SsbUOiGAOuvWdsK8rmR 8q36BvMo3DVDiTTNbn7dkmL4uBsE+ssvs7AUmZ7IPV4OwCOyZjsu9A4Fu7IPWtfZK2Xl 4OYeIsOVVe9bdnJxIww8OWT1tWG02KCIqVqPSucHfGwI6ddvN9UQuZLlkvvH7ZBK+9sO r6tg== X-Forwarded-Encrypted: i=1; AHgh+RoOauty2aq+DY2q0OTRNwhclu6LhTL/hevAp1EMCoy2sRuFZt14ALu6Pm6jIhcuZtIjaCMmeg5HNYcX73M=@vger.kernel.org X-Gm-Message-State: AFuF++lRcGLDoCU/KHTSyOPE3xbxBueV/Us8oMpbgxchL3Ww5NCBcXC6 GA8vGDEir4HegcQ0cmC0bmwIlT34cBcHROG11s+t1480N7wuZ+eXNakUVTh1mW+ZQw== X-Gm-Gg: AR+sD134LT2Y1zFAbqiwFmm6jrM5v0uSD/MiLN4wV96ECV4sCws0tkjzUXdjqCEKugn gflqgWs8ltlHrTPdmKUxT8GHFScLoyYzc7vwEqHFfiwiqgRbtN+zJ2Bo1qVMNqvb79x+rXIS5Jd o6LnGsQCU5fb4znjIGcuWija8hXpW4NgP8JSS+6LoCNI5EKuWi+3wJr2jgToagsDZsl40nzTQFK IxjUodCOSJVTbLt7QJO7FF740Oox1GRuvfTYx8+g8OdWrVYiY0x8r8b8ZY6VGqYgATJv19f3pWa j6gYlsTGLi63huZupBnQTOPZRUlIPVVj6s1XRZaPlxvzM3EyJoxfwnHXO6jRzRFVk91+qByKLJm wTggTf+yZFLRxxyztstTFDMM2MxT8IcHLJassUYnj2JTfbljuW7WDTD/obm3m94zVDZ3/Eg5YcT 5xTViSTSWawsLlwr6OfudUQGRtPi3XL+mfSY2wKeKEPSpDHESooDRZlwQMACHOgUJr3UIHMkNdE RggNj3zGzqB86OAafwOCL959AM+y2eVCg1A X-Received: by 2002:a17:903:2384:b0:2d5:db3d:1a44 with SMTP id d9443c01a7336-2d673bfffd2mr8845215ad.17.1787578987936; Mon, 24 Aug 2026 06:43:07 -0700 (PDT) Received: from google.com (164.210.142.34.bc.googleusercontent.com. [34.142.210.164]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-395e4b2b97fsm10656102a91.16.2026.08.24.06.43.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Aug 2026 06:43:07 -0700 (PDT) Date: Mon, 24 Aug 2026 13:42:58 +0000 From: Pranjal Shrivastava To: David Matlack Cc: kexec@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, Adithya Jayachandran , Alexander Graf , Alex Williamson , Bjorn Helgaas , Chris Li , David Rientjes , Jacob Pan , Jason Gunthorpe , Jonathan Corbet , Josh Hilke , Leon Romanovsky , Lukas Wunner , Mike Rapoport , Parav Pandit , Pasha Tatashin , Pratyush Yadav , Saeed Mahameed , Samiullah Khawaja , Shuah Khan , Vipin Sharma , William Tu , Yi Liu Subject: Re: [PATCH v8 08/12] PCI: liveupdate: Adopt ACS controls in incoming preserved devices Message-ID: References: <20260728221007.2098560-1-dmatlack@google.com> <20260728221007.2098560-9-dmatlack@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260728221007.2098560-9-dmatlack@google.com> On Tue, Jul 28, 2026 at 10:10:02PM +0000, David Matlack wrote: > Adopt Access Control Services (ACS) controls on all incoming preserved > devices (endpoints and upstream bridges) during a Live Update. > > Inheriting ACS flags avoids changing routing rules while memory > transactions are in flight from preserved devices. This is also strictly > necessary to ensure that IOMMU group assignments do not change during or > after Live Update. > > Cache the inherited ACS controls established by the previous kernel in > struct pci_dev so that ACS controls do not change after a reset > (pci_restore_state() calls pci_enable_acs()). > > To simplify ACS inheritance, reject preserving any devices that require > quirks to enable ACS as those quirks would also have to take Live Update > into account. > > Reviewed-by: Pasha Tatashin > Signed-off-by: David Matlack Reviewed-by: Pranjal Shrivastava Thanks, Praan