From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bmailout1.hostsharing.net (bmailout1.hostsharing.net [83.223.95.100]) (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 BE95C2045AD; Fri, 20 Feb 2026 11:45:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=83.223.95.100 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771587930; cv=none; b=bGo82lc+vJZrkhDP4mMAvEV/rGbopbjImWVBy4YTaw8M9Z/5/iAb+6Er2g3DO+SGVuSvlBrtUeuv/t8uDGV/wZB5LSYBCIRqYRzA6OuhpRXiWh5aOm5SZYfYWu2UwEaKbuobpBXnAZxwdQNpUCh0jtKB0SV3WOEW3EOJ07zciPQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771587930; c=relaxed/simple; bh=SulkP6+PfQG4DexfHMgTizwen4Gpni8L3ImOizm4iag=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=EHQUFt0ymo1c9aWArUrowXGqZfHEZ8ZmsKXcr8JrGB2uF1GHfUqMFKNPatTTxCeg8UNFSzkQ2w5H9jX5n2QwgXQjBvxwGvFYuegO3VOYrbXNr3BOrfp+qrild2SU53vOGHVa+jo6iVbf0D9w/bSTfaAU4L1p/F4K+GmWYRgsHf4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de; spf=none smtp.mailfrom=h08.hostsharing.net; arc=none smtp.client-ip=83.223.95.100 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=h08.hostsharing.net Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384 client-signature ECDSA (secp384r1) client-digest SHA384) (Client CN "*.hostsharing.net", Issuer "GlobalSign GCC R6 AlphaSSL CA 2025" (verified OK)) by bmailout1.hostsharing.net (Postfix) with ESMTPS id 2BED3202011E; Fri, 20 Feb 2026 12:45:20 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 020F5100E1; Fri, 20 Feb 2026 12:45:19 +0100 (CET) Date: Fri, 20 Feb 2026 12:45:19 +0100 From: Lukas Wunner To: Greg KH Cc: Jason Gunthorpe , dan.j.williams@intel.com, Alistair Francis , bhelgaas@google.com, rust-for-linux@vger.kernel.org, akpm@linux-foundation.org, linux-pci@vger.kernel.org, Jonathan.Cameron@huawei.com, linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org, alex.gaynor@gmail.com, benno.lossin@proton.me, boqun.feng@gmail.com, a.hindborg@kernel.org, gary@garyguo.net, bjorn3_gh@protonmail.com, tmgross@umich.edu, ojeda@kernel.org, wilfred.mallawa@wdc.com, aliceryhl@google.com, Alistair Francis , aneesh.kumar@kernel.org, yilun.xu@linux.intel.com, aik@amd.com Subject: Re: [RFC v3 00/27] lib: Rust implementation of SPDM Message-ID: References: <20260219124313.GE723117@nvidia.com> <20260219124119.GD723117@nvidia.com> <2026021944-material-hardhat-c508@gregkh> <2026022028-upstage-dollop-ee16@gregkh> Precedence: bulk X-Mailing-List: rust-for-linux@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: <2026022028-upstage-dollop-ee16@gregkh> On Fri, Feb 20, 2026 at 10:14:56AM +0100, Greg KH wrote: > On Fri, Feb 20, 2026 at 08:46:21AM +0100, Lukas Wunner wrote: > > On Thu, Feb 19, 2026 at 03:40:25PM +0100, Greg KH wrote: > > > On Thu, Feb 19, 2026 at 03:15:34PM +0100, Lukas Wunner wrote: > > > > # What's the certificate chain in slot0? > > > > openssl storeutl -text /sys/bus/pci/devices/0000:03:00.0/certificates/slot0 > > > > > > > > # Fingerprint of root cert in slot0, does it match what vendor claims? > > > > openssl x509 -fingerprint -in /sys/bus/pci/devices/0000:03:00.0/certificates/slot0 > > > > > > > > # Looks good, let's trust it: > > > > keyctl padd asymmetric "" %:.cma < /sys/bus/pci/devices/0000:03:00.0/certificates/slot0 > > > > So if a device is removed and a different one added between steps 2 and > three above, with the same pci number, all is ok? > > Remember, PCI device ids are not unique, they can come and go and be > reordered and reused at any point in time. They are fully dynamic and > should NEVER be used as a unique identifier except for a specific moment > in time. > > In other words, you are expecting that device id to always refer to the > same device across all 3 operations, which is never guaranteed. If the user chooses to replace the device between steps 2 and 3, they get to keep the pieces. Thanks, Lukas