From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27FADC433F5 for ; Fri, 4 Feb 2022 11:10:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355457AbiBDLKT (ORCPT ); Fri, 4 Feb 2022 06:10:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57670 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233079AbiBDLKS (ORCPT ); Fri, 4 Feb 2022 06:10:18 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0196AC061714 for ; Fri, 4 Feb 2022 03:10:17 -0800 (PST) Date: Fri, 4 Feb 2022 12:10:13 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1643973015; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=b9MRTqB0n9ccPXPwZOj3EH+x5hdIJMCMAmpD+JN93Ng=; b=oc1hOTQRI9eJR1sii2obCVj4iRkVhy2ikIhKFz5DkqpsX6eKVH+6GLY7JPMJDo0nsCD4gc m4FUwFkitlIS+JU6xwXtabK3b23NZWh1TRLAvfNwWIjl5IWicWyZz4fRc/c4AlXRExB3+z NxZFkHL3ImhmCI0GG4OfJDxnO/Wy+VOEX0X5vOx5vXWhXzMFn9WZZ1Is1Mave7FVuMToWs 7QoZNirJmnbYhAqeFsHCj40KDmS6zAp1ytdcvUqixmlR48NkouSOF+73SSvqmzIVq8PkJ4 52uW1ldIcQs0T8e63UdcH5dK78OS++wYI98BvsjSerCVJGplh0ODhUqscxVfBg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1643973015; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=b9MRTqB0n9ccPXPwZOj3EH+x5hdIJMCMAmpD+JN93Ng=; b=XLWZl/vD9OSiIFjekcSk4adN5cuzfH/mH/NgqeOAKV0EZ+6OxwhJnpgn4gYyy1WeynnmWc xTRYOBi3RBDEn7BA== From: Sebastian Andrzej Siewior To: "Jason A. Donenfeld" Cc: Andy Lutomirski , Boqun Feng , Will Deacon , Peter Zijlstra , Ingo Molnar , Waiman Long , Sultan Alsawaf , Theodore Ts'o , Andy Lutomirski , Jonathan =?utf-8?Q?Neusch=C3=A4fer?= , LKML , Thomas Gleixner Subject: Re: [PATCH v2] random: remove batched entropy locking Message-ID: References: <20220128223548.97807-1-Jason@zx2c4.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-02-04 01:27:55 [+0100], Jason A. Donenfeld wrote: > Hey Andy, >=20 > Think I could bug you to review this patch? The general idea is based > on your original patch, and I think this fits what we talked about on > IRC. I figure we'll probably both page this out of our minds after > another week or two of not thinking about it. >=20 > It's here on cgit if that's easier to look at: > https://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git/commit/?h= =3Djd/no-batch-lock Please don't merge this: - This splat only occurs with CONFIG_PROVE_RAW_LOCK_NESTING enabled. This option has this in its description: =E2=94=82 NOTE: There are known nesting problems. So if you enable this =E2=94=82 option expect lockdep splats until these problems have been ful= ly =E2=94=82 addressed which is work in progress. This config switch allows = to =E2=94=82 identify and analyze these problems. It will be removed and the =E2=94=82 check permanently enabled once the main issues have been fixed. - The problem identified by the splat affects only PREEMPT_RT. Non-RT is not affected by this. - This patch disables interrupts and invokes extract_crng() which leads to other problems. If this patch is the way then it should be merged together with the other outstanding issues. > Thanks, > Jason Sebastian