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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1936EC83F10 for ; Thu, 31 Aug 2023 10:13:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=HWRxhJITnb/d0BZIGqDnsCi+KtTBLxfQpafh3KKVtFM=; b=ehGBQxGYPCL/A7 8eT4ivNxNuX1yH3FL17gHnEC5pNsEvDy1owpZGEBgSDQFxL+D1Z/0GAT6jq5+d73SdH1V4acNdmrr 4gt+uRLDDNtRgvjQqUGth0mXeZ+45PrWVGFEPWitDTiwyWAaedKgzec0wP2R+8sB37+9pff+UK+Ze skVzQgS20WUCuOliVGSS/yWW8+NhuCBDzM5JDTrzPb7G0ky0rJEyKp8+QOomU1QfZte+ohmTEiyav Ze5V0d6DZkHE/q9uvo/f6qbamlOpLzM4759gIIObP1lmXv0lhV92P9hUowYt02o/MepKkanDK1HmB Unf+N5WqMe7P8kcWxfgw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qbefX-00EzhI-0m; Thu, 31 Aug 2023 10:12:55 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qbefT-00Ezgd-0z for linux-arm-kernel@lists.infradead.org; Thu, 31 Aug 2023 10:12:53 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5DF75C15; Thu, 31 Aug 2023 03:13:27 -0700 (PDT) Received: from FVFF77S0Q05N (unknown [10.57.3.201]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5E2853F64C; Thu, 31 Aug 2023 03:12:42 -0700 (PDT) Date: Thu, 31 Aug 2023 11:12:34 +0100 From: Mark Rutland To: Douglas Anderson Cc: Catalin Marinas , Will Deacon , Sumit Garg , Daniel Thompson , Marc Zyngier , linux-arm-kernel@lists.infradead.org, Masayoshi Mizuma , "Rafael J . Wysocki" , Chen-Yu Tsai , Lecopzer Chen , Tomohiro Misono , Stephane Eranian , kgdb-bugreport@lists.sourceforge.net, Peter Zijlstra , Thomas Gleixner , Stephen Boyd , ito-yuichi@fujitsu.com, linux-perf-users@vger.kernel.org, Ard Biesheuvel , D Scott Phillips , Josh Poimboeuf , Valentin Schneider , linux-kernel@vger.kernel.org Subject: Re: [PATCH v12 5/7] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI Message-ID: References: <20230830191314.1618136-1-dianders@chromium.org> <20230830121115.v12.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230830121115.v12.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230831_031251_388044_B3AB3719 X-CRM114-Status: GOOD ( 18.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Aug 30, 2023 at 12:11:26PM -0700, Douglas Anderson wrote: > There's no reason why IPI_CPU_STOP and IPI_CPU_CRASH_STOP can't be > handled as NMI. They are very simple and everything in them is > NMI-safe. Mark them as things to use NMI for if NMI is available. > > Suggested-by: Mark Rutland > Reviewed-by: Stephen Boyd > Reviewed-by: Misono Tomohiro > Reviewed-by: Sumit Garg > Signed-off-by: Douglas Anderson > --- > I don't actually have any good way to test/validate this patch. It's > added to the series at Mark's request. I've just sent out an LKDTM test that can be used to test this: http://lore.kernel.org/lkml/20230831101026.3122590-1-mark.rutland@arm.com So FWIW: Acked-by: Mark Rutland Tested-by: Mark Rutland Mark. > > (no changes since v10) > > Changes in v10: > - ("IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI") new for v10. > > arch/arm64/kernel/smp.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index 28c904ca499a..800c59cf9b64 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -946,6 +946,8 @@ static bool ipi_should_be_nmi(enum ipi_msg_type ipi) > return false; > > switch (ipi) { > + case IPI_CPU_STOP: > + case IPI_CPU_CRASH_STOP: > case IPI_CPU_BACKTRACE: > return true; > default: > -- > 2.42.0.283.g2d96d420d3-goog > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel