From nobody Thu Dec 18 14:30:35 2025 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 5A5F5EE49A5 for ; Thu, 24 Aug 2023 15:34:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242252AbjHXPds (ORCPT ); Thu, 24 Aug 2023 11:33:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242233AbjHXPdM (ORCPT ); Thu, 24 Aug 2023 11:33:12 -0400 Received: from mail-pf1-x42c.google.com (mail-pf1-x42c.google.com [IPv6:2607:f8b0:4864:20::42c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DE225CEE for ; Thu, 24 Aug 2023 08:33:10 -0700 (PDT) Received: by mail-pf1-x42c.google.com with SMTP id d2e1a72fcca58-68a402c1fcdso3409089b3a.1 for ; Thu, 24 Aug 2023 08:33:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1692891190; x=1693495990; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=+U+ZFko4eaNVS/k5E5YRzxI9X7/KmekX/8rZmWNkCMw=; b=cS5jIetqAgvoNwttMKW4WTIdVltP+nOpZ6stPUmuzAoBmw/eX/rT/dZLOJ/PnUdndx 3mg0vSOMLBUhFA54TJJKRCLbXxOTgJJLu2+gL3A90a8w+BPukvfIq7bN6HtW0VmGnhFw 6NSUkj9cgyvYTfuGsfZ/V/hb/l98o3t6zQmQI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692891190; x=1693495990; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=+U+ZFko4eaNVS/k5E5YRzxI9X7/KmekX/8rZmWNkCMw=; b=YuxfgRZ9L4E3JksZnOMVtXBiKIj1ZhnyRr2/DP36t/nb/nlC5YBvG8W9iLaOnJ0eom P+UbubG8jTIx1EQkos+62DXluhEo5vddWTR54ktK3Ojc4SWYHoXFySLrIRUaFtIugTBy FXXaD9Jit7weZN32mvtMd9ftlays/cpGJrAGJNwJbZXL7/cNSAYmhS7qmHigyYmHBpLf SJ08nPu95eKNOfFe2jYuGaeVxGD0YfW7OFtx4bh9JnbTt7boedFrx+S2YgpUoBbuEgzu 9d0rQZ8ffhxqQYJ70t0zuJniZtOMJVaPDrqgpluMG8xE1DDt9iqgTcj3dwJSiwDg2+Fw ffIQ== X-Gm-Message-State: AOJu0YyfbEgZXHsBPwr02R4X2O/baraZhJk1icu+P6HScm5TQzhVbBzL EC9IDRMgaap2ZvcLugrEILM5eezj3OXF5f9tkOCH2zLf X-Google-Smtp-Source: AGHT+IHaSpjbeAQ9UzHqXXC2nf4Z9xB3fbVm9xxQZ6RsAAdQhINpMo2utUL4uLzKK7MxM211qE78FA== X-Received: by 2002:a05:6a00:124b:b0:68a:582b:44c4 with SMTP id u11-20020a056a00124b00b0068a582b44c4mr9603241pfi.3.1692891190414; Thu, 24 Aug 2023 08:33:10 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:afa3:fcf5:1b7f:f7e2]) by smtp.gmail.com with ESMTPSA id m30-20020a63711e000000b0056365ee8603sm11631337pgc.67.2023.08.24.08.33.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 24 Aug 2023 08:33:09 -0700 (PDT) From: Douglas Anderson To: Mark Rutland , Catalin Marinas , Will Deacon , Sumit Garg , Daniel Thompson , Marc Zyngier Cc: "Rafael J . Wysocki" , Ard Biesheuvel , Thomas Gleixner , kgdb-bugreport@lists.sourceforge.net, Lecopzer Chen , linux-perf-users@vger.kernel.org, Masayoshi Mizuma , Chen-Yu Tsai , linux-arm-kernel@lists.infradead.org, ito-yuichi@fujitsu.com, Stephen Boyd , Peter Zijlstra , Douglas Anderson , D Scott Phillips , Ingo Molnar , Josh Poimboeuf , Valentin Schneider , linux-kernel@vger.kernel.org Subject: [PATCH v11 5/6] arm64: smp: IPI_CPU_STOP and IPI_CPU_CRASH_STOP should try for NMI Date: Thu, 24 Aug 2023 08:30:31 -0700 Message-ID: <20230824083012.v11.5.Ifadbfd45b22c52edcb499034dd4783d096343260@changeid> X-Mailer: git-send-email 2.42.0.rc1.204.g551eb34607-goog In-Reply-To: <20230824153233.1006420-1-dianders@chromium.org> References: <20230824153233.1006420-1-dianders@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" 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 Signed-off-by: Douglas Anderson Reviewed-by: Sumit Garg --- I don't actually have any good way to test/validate this patch. It's added to the series at Mark's request. (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 c8896cbc5327..4566934aaf9f 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; =20 switch (ipi) { + case IPI_CPU_STOP: + case IPI_CPU_CRASH_STOP: case IPI_CPU_BACKTRACE: return true; default: --=20 2.42.0.rc1.204.g551eb34607-goog