From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 859093E3D96; Mon, 27 Apr 2026 19:09:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777316986; cv=none; b=Y5d26dzit+L7dc2YMUOy3QhkNvr8EjUXXrYd6itmCm7HW88alyoyqm7yxeZm+OX0F8IHL7S4RtJGRzteNKwJlxjZBi4KvzEzU2DwSCY8zVn7tZCg/r5jT9enluHu+ZUh5O+DA+Z5vnpnFcWOCWUVWYUWrSmMhDSpa8ov/ZnRsJc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777316986; c=relaxed/simple; bh=GuYS9/hGtuZHiXcvekyT34pWb9SYDnOOkCWMLXLGHTk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KLGVp8KTcGW54MvP4ZflXyuFJ6XpiCqiQZNctIZixvvVJGR7Mx0oH1jf3ejR09w4oAliLepljMNUqYvuKIv4htgczRjH2oe1JQ4BtABGi/t7sorYj8MlOW9NjlV+rZU35jgVK/Ek2gfR247tZcY3fRCL2WbtryvODruQCVXKMYQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RAwze+ZM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RAwze+ZM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72D57C19425; Mon, 27 Apr 2026 19:09:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777316986; bh=GuYS9/hGtuZHiXcvekyT34pWb9SYDnOOkCWMLXLGHTk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=RAwze+ZMMcoOyFQlsJS/GytKxSTe7le7s0F/ZA2SrC1cKMiNf+qxqRa5HzKQmW6UN ufEjPc4lK+WmwF6l6Zey5obs9qNgRb/YQl1xofDcyVWGdkNVwO/BiUh1LZg/HNw8mb vY3F4DWaUqWxHe7o17v/Iihk479UFuHBHAr1n4sozEWcO27Y5H6vS5/QasNyLp6vUw SUJrUeqALqdZml0Cd9wt70zEVneckpA+raAYCs22W7oLmBCTninvubV3mwqNDqMqGI V/K+9JZjUpOSWJwjgC0gmbDVP6RZWGA5N0Ew938dfPABVn2x0EHgDeW3V614oQyl1r w3z5II298HHxw== Date: Mon, 27 Apr 2026 22:09:41 +0300 From: Leon Romanovsky To: Jason Gunthorpe Cc: Paul Moore , Roberto Sassu , KP Singh , Matt Bobrowski , Alexei Starovoitov , Daniel Borkmann , John Fastabend , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , Stanislav Fomichev , Hao Luo , Jiri Olsa , Shuah Khan , Saeed Mahameed , Itay Avraham , Dave Jiang , Jonathan Cameron , bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-rdma@vger.kernel.org, Chiara Meiohas , Maher Sanalla , linux-security-module@vger.kernel.org Subject: Re: [PATCH v2 0/4] Firmware LSM hook Message-ID: <20260427190941.GN440345@unreal> References: <20260413231920.GS3694781@ziepe.ca> <20260415134705.GG2577880@ziepe.ca> <20260417191749.GK2577880@ziepe.ca> <20260423140950.GE172828@unreal> <20260424141921.GA3611611@ziepe.ca> <20260426103957.GH172828@unreal> <20260426134224.GC3501894@ziepe.ca> Precedence: bulk X-Mailing-List: bpf@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: <20260426134224.GC3501894@ziepe.ca> On Sun, Apr 26, 2026 at 10:42:24AM -0300, Jason Gunthorpe wrote: > On Sun, Apr 26, 2026 at 01:39:57PM +0300, Leon Romanovsky wrote: > > On Fri, Apr 24, 2026 at 11:19:21AM -0300, Jason Gunthorpe wrote: > > > On Thu, Apr 23, 2026 at 05:09:50PM +0300, Leon Romanovsky wrote: > > > > > > > > > Leon mentioned that different firmware revisions would have different > > > > > > parameters for a given opcode, and that one would need to inspect > > > > > > those parameters to properly filter the command. Is that not true, or > > > > > > am I misreading or misunderstanding Leon's comments? > > > > > > > > > > They are ABI stable, so there will be rules about future changes that > > > > > old software can follow to ignore or reject future things it doesn't > > > > > understand. > > > > > > > > It is wishful thinking and applicable only to mlx5 devices. No one > > > > promises that other devices follow same ABI rules. > > > > > > Well, I will definately kick them out of fwctl if they don't. > > > > It is easy to say but harder to follow. The kernel includes many devices that > > exist only in specific hyperscale environments, where the update cycle is > > tightly controlled. They easily can break FW backward compatibility. > > Well Linus's rule applies here, if it doesn't bother anyone it didn't > break.. Great, that means they can load any BPF program they want and access whatever firmware fields they choose. Your earlier claim about 'not breaking FW compatibility' is only partially correct. Thanks > > Jason >