From patchwork Mon Oct 2 16:45:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 147449 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2a8e:b0:403:3b70:6f57 with SMTP id in14csp1660997vqb; Mon, 2 Oct 2023 13:03:07 -0700 (PDT) X-Google-Smtp-Source: AGHT+IErhoCpQJq5mU95sfHscL1NtBtjPQbqgAWBrIOq/TM5MjCY9+MUedWyAyF0LS3/EkQz1jIr X-Received: by 2002:a17:90a:f697:b0:277:298:deae with SMTP id cl23-20020a17090af69700b002770298deaemr9859021pjb.11.1696276987399; Mon, 02 Oct 2023 13:03:07 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696276987; cv=none; d=google.com; s=arc-20160816; b=0oWbczE8Z54+1Ie88KD0X2v10LGah1hUkMrC5oa5/Bh7Bg/eRa69kvgHfdIXzLj1e8 9KElQd8VvfUjjGsGXhgzOGVxlUUUS9ig1OvSlirVoLygdej3z3Z7GHNRgwz5ool4zvku kr5IIdGnKGYWUvenmIW9TWWt5+QsYmEcoLNLxWspr+aS9s7tf//f/IjG1S4CurMSFiKm UDTjD8q7loom5hlLmdwQXsIGjlFiR5vTKBc41QJOI9h/eTGLItxQtKEtKqenCRmq+QNZ MUExFbvJ+CztTvjMCQg7D78DsAL6V/88UoXlGx02YyCMfgcJfKrIsGxnZ8AfGhD/K5WM g/tQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :message-id:date:subject:cc:to:from:dkim-signature; bh=aLqyuV3WHU1tmRucfRRbNKiUdX9Z1rFjqb2ZE34s0NQ=; fh=Xd8m98G3zYjT7EFfkHwZAQA/eXp27is4MrKgKacKrUg=; b=WLsuSliuC4ebPengeXrmEm5xgnJBeKsxdQYtkBTP5fhJEiiSZOdmw9ua2wn/kgZpXw 900+mpmwzONaRYQQ/YzBjizPQMTdX3rIXTGZRwj2kLK22F9P5YsxXVuMbpQDq1P2P1ZO xYp/bibX6f+a6qN2go38bV8y/i+gSX3+B90y77tb6aE9TQreZW8tfbkyuzZMVhqFgGrS 6hJx7izRmWAHFJwrZ5Oe0HCwd2YMkr1+WuU6MvKC950ri4uVupKLr7Fcvqto7/23sYul h7ZxKURa7p58A7z+HED9WfhOScRfZuVUvXzXt1DUZR7VW/qV7b/Zxwzji/iA6pYG/L86 PYHQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=CaHKVNGl; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from howler.vger.email (howler.vger.email. [23.128.96.34]) by mx.google.com with ESMTPS id bv64-20020a632e43000000b00578666614f1si28365826pgb.63.2023.10.02.13.03.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Oct 2023 13:03:07 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=CaHKVNGl; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id 089E480A8543; Mon, 2 Oct 2023 09:46:41 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238326AbjJBQqX (ORCPT + 18 others); Mon, 2 Oct 2023 12:46:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237844AbjJBQqT (ORCPT ); Mon, 2 Oct 2023 12:46:19 -0400 Received: from mail-pg1-x534.google.com (mail-pg1-x534.google.com [IPv6:2607:f8b0:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89748D7 for ; Mon, 2 Oct 2023 09:46:14 -0700 (PDT) Received: by mail-pg1-x534.google.com with SMTP id 41be03b00d2f7-5859b06509cso2383822a12.2 for ; Mon, 02 Oct 2023 09:46:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1696265174; x=1696869974; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=aLqyuV3WHU1tmRucfRRbNKiUdX9Z1rFjqb2ZE34s0NQ=; b=CaHKVNGliyYtM9Fb0sKWpA+KcRNU5qTHzmNc/IJOKFYYOjDzswi9zOhkK2mhgF0Aix ohiNH1VaomGyVPARikWgxgmuOabKGhGEroCRYK2zeAwxaqp+nWGdyb7slIU7QnCYe+v9 JfpYaIoLu2os/jp81jFr6wErV6ezqlb/ltFRA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696265174; x=1696869974; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=aLqyuV3WHU1tmRucfRRbNKiUdX9Z1rFjqb2ZE34s0NQ=; b=LC7LM6t6ZhnfWXQdvc2V/Kq0W3Hd96G4eXEKb6vBSTsTVQqMsTWJm8MWq0cPb4dy0s YhMt2G7lMPufcchkZIlxZJBe1WOmCLH54j+B9vzM9xMd9HxIX8bVHk/Hk/shupRD98OZ Ov7hQj5edu/wbo6tbXIiwV935b/tb0I7zsgQsAKXxZyo+jEsb5Xw8tCtO+zMU23jv4y0 GnlSxDVoGVFy0ZQUwKqC7pO9c5xyJQAehJaUv1HP2Ai4HRpROklbGQn/8xUN4sLCVOtt OxLagssPW2CAiHeHdFVaO5rJthqSD3jL9jc01rVR9+11R+jIZjwS37iioNRGtt/unc+v G4KQ== X-Gm-Message-State: AOJu0Ywh5zvpxPd0ced07/wYmDKMyExgm7BaY3HitnWcXreebeAFK63x +oPRv1z10gDFkGxHKhmIJmLkIg== X-Received: by 2002:a05:6a20:a110:b0:13d:1d14:6693 with SMTP id q16-20020a056a20a11000b0013d1d146693mr12076717pzk.45.1696265173921; Mon, 02 Oct 2023 09:46:13 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:bb:b2b6:1831:5edd]) by smtp.gmail.com with ESMTPSA id n3-20020a170902d2c300b001c737950e4dsm8455904plc.2.2023.10.02.09.46.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 02 Oct 2023 09:46:13 -0700 (PDT) From: Douglas Anderson To: Catalin Marinas , Will Deacon , Mark Rutland , Marc Zyngier Cc: Stephen Boyd , Valentin Schneider , Chen-Yu Tsai , Douglas Anderson , AngeloGioacchino Del Regno , D Scott Phillips , Josh Poimboeuf , Matthias Brugger , Misono Tomohiro , Peter Zijlstra , Sumit Garg , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org Subject: [PATCH 1/2] arm64: smp: Fix pseudo NMI issues w/ broken Mediatek FW Date: Mon, 2 Oct 2023 09:45:29 -0700 Message-ID: <20231002094526.1.Ie8f760213053e3d11592f892b30912dbac6b8b48@changeid> X-Mailer: git-send-email 2.42.0.582.g8ccd20d70d-goog MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, RCVD_IN_DNSWL_BLOCKED,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Mon, 02 Oct 2023 09:46:41 -0700 (PDT) X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1778666274734121974 X-GMAIL-MSGID: 1778675338276329245 Some mediatek devices have the property "mediatek,broken-save-restore-fw" in their GIC. This means that, although the hardware supports pseudo-NMI, the firmware has a bug that blocks enabling it. When we're in this state, system_uses_irq_prio_masking() will return true but we'll fail to actually enable the IRQ in the GIC. Let's make the code handle this. We'll detect that we failed to request an IPI as NMI and fallback to requesting it normally. Though we expect that either all of our requests will fail or all will succeed, it's just as cheap to keep a per-IPI bitmap and that keeps us robust. Fixes: 331a1b3a836c ("arm64: smp: Add arch support for backtrace using pseudo-NMI") Reported-by: Chen-Yu Tsai Closes: https://issuetracker.google.com/issues/197061987#comment68 Signed-off-by: Douglas Anderson Reviewed-by: Douglas Anderson Tested-by: Douglas Anderson Reviewed-by: Marc Zyngier Tested-by: Chen-Yu Tsai --- arch/arm64/kernel/smp.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 814d9aa93b21..0a6002243a8c 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -87,6 +87,7 @@ enum ipi_msg_type { static int ipi_irq_base __ro_after_init; static int nr_ipi __ro_after_init = NR_IPI; static struct irq_desc *ipi_desc[MAX_IPI] __ro_after_init; +DECLARE_BITMAP(ipi_is_nmi, MAX_IPI); static void ipi_setup(int cpu); @@ -986,7 +987,7 @@ static void ipi_setup(int cpu) return; for (i = 0; i < nr_ipi; i++) { - if (ipi_should_be_nmi(i)) { + if (test_bit(i, ipi_is_nmi)) { prepare_percpu_nmi(ipi_irq_base + i); enable_percpu_nmi(ipi_irq_base + i, 0); } else { @@ -1004,7 +1005,7 @@ static void ipi_teardown(int cpu) return; for (i = 0; i < nr_ipi; i++) { - if (ipi_should_be_nmi(i)) { + if (test_bit(i, ipi_is_nmi)) { disable_percpu_nmi(ipi_irq_base + i); teardown_percpu_nmi(ipi_irq_base + i); } else { @@ -1022,17 +1023,21 @@ void __init set_smp_ipi_range(int ipi_base, int n) nr_ipi = min(n, MAX_IPI); for (i = 0; i < nr_ipi; i++) { - int err; + int err = -EINVAL; if (ipi_should_be_nmi(i)) { err = request_percpu_nmi(ipi_base + i, ipi_handler, "IPI", &cpu_number); - WARN(err, "Could not request IPI %d as NMI, err=%d\n", - i, err); - } else { + if (err) + pr_info_once("NMI unavailable; fallback to IRQ\n"); + else + set_bit(i, ipi_is_nmi); + } + + if (err) { err = request_percpu_irq(ipi_base + i, ipi_handler, "IPI", &cpu_number); - WARN(err, "Could not request IPI %d as IRQ, err=%d\n", + WARN(err, "Could not request IPI %d, err=%d\n", i, err); } From patchwork Mon Oct 2 16:45:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 147537 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:2a8e:b0:403:3b70:6f57 with SMTP id in14csp1727223vqb; Mon, 2 Oct 2023 15:30:28 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEuraktdYm3PptpYvDbQ88644Z1myxUtEQJT09aoL5ehTaflwZKOJf1dGUzKjCUjmgFZ55/ X-Received: by 2002:a05:6a21:99a0:b0:140:253b:b658 with SMTP id ve32-20020a056a2199a000b00140253bb658mr13202189pzb.57.1696285828586; Mon, 02 Oct 2023 15:30:28 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696285828; cv=none; d=google.com; s=arc-20160816; b=r3zurhkl0ggqftiZ4+J1F8wAlgciDtYoNJyeMLWA+nB1Sm9CUc142PnXb3mrIStLsF fgKJyq9P/qzitFGBVsqTtJ/FPpOpR0xUOnsfzvp4nAbUO/4/2k3jhVM66AruMW3wVwbu O39yu67Uvt9+43vR2IYRhk4xSRlLnj7U+GjyXjBrhqm5sTBLc1nXAx6PYqnT4CVD3d3o y8qckGjq9LlaD0kCAtRn/DUcl1exKwLYCKuwO3EGTOYyc8wrbzayLBpAkbiT+C3DHu5u epRAMTgzp9vmfp+++8mkQPLzNnVgk1TKSLgY8E8elgpH1nxlA4OpOWLHVI1nmWO89Rq0 7hSQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=+OYydoz0zgcPlyOphP3bRXT7u9ruoeqId11POu4ytwI=; fh=pZ9UizG2yMvstUfFfsYp5su8tDMJIiAtJ6XUlL6trFY=; b=xi8HTAV4jLZSbkP+D+ZnrjS6FAU8kIVJmDLLrtO+rVJZ5KUkoloVDBKOAW4VVNHIWE atrZL0gi0PW22B/SCH5Cg1DBivao/ScUJSs0vS3pBsyceIP+bV0CfGXoGWmsIXPcOL49 gPyt6lebCc2dWr5n9X0hrwoIWF9NL+ZbCDDpcZikdRRAGUh/bJ2RsM0oXj/GZ9ZDQZCQ es9OtPWVUMTQyEdUK/4uDkf3Ukwa5yTihzEtKjNbQThn4JvuAwPxVzf0Jop/aJeERaO2 +o+1OdJ7qzEHLWiclixR8Zp2ne/59GmaZB936DjhXQI4J3q/fxmoKQV1khSb017+rb+6 3mDA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=A0PpqRnW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from howler.vger.email (howler.vger.email. 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When we did this, we used arch_smp_send_reschedule() directly rather than calling smp_send_reschedule(). The only difference is that calling arch_smp_send_reschedule() directly avoids tracing. Presumably we _don't_ want to avoid tracing here, so switch to smp_send_reschedule(). Fixes: 2b2d0a7a96ab ("arm64: smp: Remove dedicated wakeup IPI") Signed-off-by: Douglas Anderson --- I don't 100% know if this is correct and I don't have any hardware that uses the "ACPI parking protocol", but I think it's right. My main incentive for this is that it makes it easier to backport pseudo-NMI to kernels that don't have arch_smp_send_reschedule(), but I think it's also more correct. If for some reason we truly did want to avoid tracing here, please shout and we can drop this patch. arch/arm64/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 0a6002243a8c..b530d8ef9c1d 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -1063,7 +1063,7 @@ void arch_send_wakeup_ipi(unsigned int cpu) * We use a scheduler IPI to wake the CPU as this avoids the need for a * dedicated IPI and we can safely handle spurious scheduler IPIs. */ - arch_smp_send_reschedule(cpu); + smp_send_reschedule(cpu); } #endif