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 40F26C433EF for ; Mon, 31 Jan 2022 10:24:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358132AbiAaKYA (ORCPT ); Mon, 31 Jan 2022 05:24:00 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:58542 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358122AbiAaKX4 (ORCPT ); Mon, 31 Jan 2022 05:23:56 -0500 Date: Mon, 31 Jan 2022 11:23:52 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1643624633; 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: in-reply-to:in-reply-to:references:references; bh=KP118xyiOlCfNk6Yd6qwpbFDC5oBogtckl9rVGfc3U4=; b=1qqMupU1R69pNXQ/TeFSoXrMek18fQYm3CcWo22+BNV0gvpzOnj0/2zBU81yHvGmd3CzPI Z0b5+It4pK6zgzj3Q5tQUzYR0puoqFdctdXjTXc9+QiMOISO6bUOoDEdz5YNYiYy9vMKob ZY8i4ifLPQGJEewcDzITyVmvKtV4her+Tv1KXbIZE9v5YXL5iMZyblZ697BBQic/wzT3+O XLlZZH0iJROtnuCTOEfahzwp3XQ4JoAGg+oaw2W53qzikqJjbV0GCzZkx/1nR6EKxbva73 nMAZ5WBgFM02EFqx8/M5NwfcEMPtYCsCRuRvaUDdf0GdSxiRuhzYMGAbJUJrUw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1643624633; 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: in-reply-to:in-reply-to:references:references; bh=KP118xyiOlCfNk6Yd6qwpbFDC5oBogtckl9rVGfc3U4=; b=E/2C2AXQkKgwmIl3KTMx+DqHKQS7paMznJWUUCeCefUq64ONtb2twfK0tt02MTsp7fnzjz ca7gtMjUE+FLQCCA== From: Sebastian Andrzej Siewior To: Clark Williams Cc: Steven Rostedt , Thomas Gleixner , linux-rt-users@vger.kernel.org, williams@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH PREEMPT_RT 4.19 STABLE] rt: PREEMPT_RT safety net for backported patches Message-ID: References: <20220130221944.7992CC340E4@smtp.kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20220130221944.7992CC340E4@smtp.kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-rt-users@vger.kernel.org On 2022-01-30 15:46:27 [-0600], Clark Williams wrote: > While doing some 4.19-rt cleanup work, I stumbled across the fact that parts of > two backported patches were dependent on CONFIG_PREEMPT_RT, rather than > the CONFIG_PREEMPT_RT_FULL used in 4.19 and earlier RT series. The commits > in the linux-stable-rt v4.19-rt branch are: > > dad4c6a33bf4e mm: slub: Don't resize the location tracking cache on PREEMPT_RT > e626b6f873f2c net: Treat __napi_schedule_irqoff() as __napi_schedule() on PREEMPT_RT > > Discussing this at the Stable RT maintainers meeting, Steven Rostedt suggested that > we automagically select CONFIG_PREEMPT_RT if CONFIG_PREEMPT_RT_FULL is on, giving > us a safety net for any subsequently backported patches. Here's my first cut at > that patch. > > I suspect we'll need a similar patch for stable RT kernels < 4.19. > > Suggested-by: Steven Rostedt > Signed-off-by: Clark Williams Acked-by: Sebastian Andrzej Siewior > --- > kernel/Kconfig.preempt | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt > index 306567f72a3e..951f58cbd652 100644 > --- a/kernel/Kconfig.preempt > +++ b/kernel/Kconfig.preempt > @@ -6,6 +6,10 @@ config PREEMPT_RT_BASE > bool > select PREEMPT > > +config PREEMPT_RT > + bool > + default false default is false. > + > config HAVE_PREEMPT_LAZY > bool > Sebastian