From patchwork Wed Sep 13 18:01:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 140122 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a05:612c:172:b0:3f2:4152:657d with SMTP id h50csp787141vqi; Thu, 14 Sep 2023 20:55:34 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEw92Y2ZfdSeutw9YKvz75YS3xsgWQYWKayl1f0r3NCbVN+wIgoJfTPpQOZgLK8Xan16Z4T X-Received: by 2002:a17:903:41c5:b0:1be:f45c:bc38 with SMTP id u5-20020a17090341c500b001bef45cbc38mr662528ple.2.1694750133874; Thu, 14 Sep 2023 20:55:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1694750133; cv=none; d=google.com; s=arc-20160816; b=VAdtJkIfE306YFuEv7rEemLKTcmUnPoPPhJqi3INTzjKmnSEWN+t6idd1Fiq7CXNow uUsoQI0kzH9LZ/Eu5/KseF3DGHFXbteAUPxupe1TriKjV4GjMZRDlWRqdEKwI9GJE7se 347y9/8NK/B6Rd8HIF7g5Z48jDOz9vZA9qXDo5nh4oqskRwDas9V3p6u2rBgk8iWgN5Y EZ79yGCHOqRbPi7AwdLBxGTagvxnn90pNRvewyk+7fKRLpjSjhz5WjWD/eiHuhJ7Gzw0 wiUPPxT59J4m5N0W6dUKO+q7L6YOKydkWbq9+RNvsOWumll8LVY9Z8muJAd2MvLK/9P3 9wJw== 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=Q6i31kdPNVz2CcylcU0YqxIfavYRU5SffpbaRRY0/L4=; fh=BiiXE8BhyFR4xzfWHGxKpxvi0Qyy3d2KeE/afcfauqc=; b=McrdhU6itJrGuO6Fc5HT0PigVkXZ0eHC4f86RrmL3F/KwzlZKI/eXSp98nHTOi57RS CAAsuVUNmpD9g1RkmrIfLgba3Jg4w1kOEulnqp3z3aYRboNlZ7qILoxaOk8hPPgyNtm+ +j7sDxNns1+yKZaQ75Sa0cJQ+vyiuC65TMTYGTEMWIhCXzesgeBbfaOjih092xaMApfo 9SPRohmFzrJGyg4WaK34O6KT4KC2UKJoW0QBKuJ9bHE/QlMdXb+K0CdEp0NtXMFW9LpK r0y5+tXesBx7mWO4tvH1pYPdwCKNo69JIxLlTUZkLeLZC2ut12M7eJ32xILinqHsuLwe M3mw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=LRfs7Bzr; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:2 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from agentk.vger.email (agentk.vger.email. [2620:137:e000::3:2]) by mx.google.com with ESMTPS id kh4-20020a170903064400b001b878f9e11csi2592910plb.54.2023.09.14.20.55.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 14 Sep 2023 20:55:33 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:2 as permitted sender) client-ip=2620:137:e000::3:2; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=LRfs7Bzr; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:2 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by agentk.vger.email (Postfix) with ESMTP id B1BCC81F88EB; Wed, 13 Sep 2023 11:02:25 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at agentk.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231622AbjIMSCQ (ORCPT + 34 others); Wed, 13 Sep 2023 14:02:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229552AbjIMSCO (ORCPT ); Wed, 13 Sep 2023 14:02:14 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 3385019AE for ; Wed, 13 Sep 2023 11:01:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694628085; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=Q6i31kdPNVz2CcylcU0YqxIfavYRU5SffpbaRRY0/L4=; b=LRfs7Bzrh+7rjhGm7b2aHxuFquE+PEhzvFztT7Zwejtfo/SzQYM+g6+CYSWXk1X/25B89x FNeWdiWLbUV/Qw5OWoj9NWhoZS3bJL1TlpDxJShYLLQ6no22TZT2DW94nO20P/CYzOVclB UR+eicZtA6xBTR0X9TJFKBaFTfkTjwQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-597-cLQ3GeOMMR-WZg_i5JKMJA-1; Wed, 13 Sep 2023 14:01:23 -0400 X-MC-Unique: cLQ3GeOMMR-WZg_i5JKMJA-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id DADCE805B32; Wed, 13 Sep 2023 18:01:21 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.192.172]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8C8212904; Wed, 13 Sep 2023 18:01:19 +0000 (UTC) From: Hans de Goede To: Steve Wahl , Justin Ernst , Kyle Meyer , Dimitri Sivanich , Russ Anderson , Darren Hart , Andy Shevchenko , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H . Peter Anvin" Cc: Hans de Goede , x86@kernel.org, linux-kernel@vger.kernel.org, Justin Stitt Subject: [PATCH v2] x86/platform/uv: Rework NMI "action" modparam handling Date: Wed, 13 Sep 2023 20:01:11 +0200 Message-ID: <20230913180111.85397-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 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 (agentk.vger.email [0.0.0.0]); Wed, 13 Sep 2023 11:02:25 -0700 (PDT) X-Spam-Status: No, score=-0.9 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on agentk.vger.email X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: 1776961268293429588 X-GMAIL-MSGID: 1777074316726684549 Rework NMI "action" modparam handling: 1. Replace the uv_nmi_action string with an enum; and 2. Use sysfs_match_string() for string parsing in param_set_action() Suggested-by: Steve Wahl Cc: Justin Stitt Signed-off-by: Hans de Goede --- Changes in v2: - Also change uv_nmi_action to an enum to replace a bunch of strcmp() calls --- arch/x86/platform/uv/uv_nmi.c | 104 +++++++++++++++++++--------------- 1 file changed, 57 insertions(+), 47 deletions(-) diff --git a/arch/x86/platform/uv/uv_nmi.c b/arch/x86/platform/uv/uv_nmi.c index 45d0c17ce77c..b92f1b4adeb0 100644 --- a/arch/x86/platform/uv/uv_nmi.c +++ b/arch/x86/platform/uv/uv_nmi.c @@ -178,49 +178,57 @@ module_param_named(debug, uv_nmi_debug, int, 0644); } while (0) /* Valid NMI Actions */ -#define ACTION_LEN 16 -static struct nmi_action { - char *action; - char *desc; -} valid_acts[] = { - { "kdump", "do kernel crash dump" }, - { "dump", "dump process stack for each cpu" }, - { "ips", "dump Inst Ptr info for each cpu" }, - { "kdb", "enter KDB (needs kgdboc= assignment)" }, - { "kgdb", "enter KGDB (needs gdb target remote)" }, - { "health", "check if CPUs respond to NMI" }, +enum action_t { + nmi_act_kdump, + nmi_act_dump, + nmi_act_ips, + nmi_act_kdb, + nmi_act_kgdb, + nmi_act_health, }; -typedef char action_t[ACTION_LEN]; -static action_t uv_nmi_action = { "dump" }; + +static const char * const actions[] = { + [nmi_act_kdump] = "kdump", + [nmi_act_dump] = "dump", + [nmi_act_ips] = "ips", + [nmi_act_kdb] = "kdb", + [nmi_act_kgdb] = "kgdb", + [nmi_act_health] = "health", +}; + +static const char * const actions_desc[] = { + [nmi_act_kdump] = "do kernel crash dump", + [nmi_act_dump] = "dump process stack for each cpu", + [nmi_act_ips] = "dump Inst Ptr info for each cpu", + [nmi_act_kdb] = "enter KDB (needs kgdboc= assignment)", + [nmi_act_kgdb] = "enter KGDB (needs gdb target remote)", + [nmi_act_health] = "check if CPUs respond to NMI", +}; + +static_assert(ARRAY_SIZE(actions) == ARRAY_SIZE(actions_desc)); + +static enum action_t uv_nmi_action = nmi_act_dump; static int param_get_action(char *buffer, const struct kernel_param *kp) { - return sprintf(buffer, "%s\n", uv_nmi_action); + return sprintf(buffer, "%s\n", actions[uv_nmi_action]); } static int param_set_action(const char *val, const struct kernel_param *kp) { - int i; - int n = ARRAY_SIZE(valid_acts); - char arg[ACTION_LEN]; + int i, n = ARRAY_SIZE(actions); - /* (remove possible '\n') */ - strscpy(arg, val, strnchrnul(val, sizeof(arg)-1, '\n') - val + 1); - - for (i = 0; i < n; i++) - if (!strcmp(arg, valid_acts[i].action)) - break; - - if (i < n) { - strscpy(uv_nmi_action, arg, sizeof(uv_nmi_action)); - pr_info("UV: New NMI action:%s\n", uv_nmi_action); + i = sysfs_match_string(actions, val); + if (i >= 0) { + uv_nmi_action = i; + pr_info("UV: New NMI action:%s\n", actions[i]); return 0; } - pr_err("UV: Invalid NMI action:%s, valid actions are:\n", arg); + pr_err("UV: Invalid NMI action:%s, valid actions are:\n", val); for (i = 0; i < n; i++) - pr_err("UV: %-8s - %s\n", - valid_acts[i].action, valid_acts[i].desc); + pr_err("UV: %-8s - %s\n", actions[i], actions_desc[i]); + return -EINVAL; } @@ -228,15 +236,10 @@ static const struct kernel_param_ops param_ops_action = { .get = param_get_action, .set = param_set_action, }; -#define param_check_action(name, p) __param_check(name, p, action_t) +#define param_check_action(name, p) __param_check(name, p, enum action_t) module_param_named(action, uv_nmi_action, action, 0644); -static inline bool uv_nmi_action_is(const char *action) -{ - return (strncmp(uv_nmi_action, action, strlen(action)) == 0); -} - /* Setup which NMI support is present in system */ static void uv_nmi_setup_mmrs(void) { @@ -727,10 +730,10 @@ static void uv_nmi_dump_state_cpu(int cpu, struct pt_regs *regs) if (cpu == 0) uv_nmi_dump_cpu_ip_hdr(); - if (current->pid != 0 || !uv_nmi_action_is("ips")) + if (current->pid != 0 || uv_nmi_action != nmi_act_ips) uv_nmi_dump_cpu_ip(cpu, regs); - if (uv_nmi_action_is("dump")) { + if (uv_nmi_action == nmi_act_dump) { pr_info("UV:%sNMI process trace for CPU %d\n", dots, cpu); show_regs(regs); } @@ -798,7 +801,7 @@ static void uv_nmi_dump_state(int cpu, struct pt_regs *regs, int master) int saved_console_loglevel = console_loglevel; pr_alert("UV: tracing %s for %d CPUs from CPU %d\n", - uv_nmi_action_is("ips") ? "IPs" : "processes", + uv_nmi_action == nmi_act_ips ? "IPs" : "processes", atomic_read(&uv_nmi_cpus_in_nmi), cpu); console_loglevel = uv_nmi_loglevel; @@ -874,7 +877,7 @@ static inline int uv_nmi_kdb_reason(void) static inline int uv_nmi_kdb_reason(void) { /* Ensure user is expecting to attach gdb remote */ - if (uv_nmi_action_is("kgdb")) + if (uv_nmi_action == nmi_act_kgdb) return 0; pr_err("UV: NMI error: KDB is not enabled in this kernel\n"); @@ -950,28 +953,35 @@ static int uv_handle_nmi(unsigned int reason, struct pt_regs *regs) master = (atomic_read(&uv_nmi_cpu) == cpu); /* If NMI action is "kdump", then attempt to do it */ - if (uv_nmi_action_is("kdump")) { + if (uv_nmi_action == nmi_act_kdump) { uv_nmi_kdump(cpu, master, regs); /* Unexpected return, revert action to "dump" */ if (master) - strscpy(uv_nmi_action, "dump", sizeof(uv_nmi_action)); + uv_nmi_action = nmi_act_dump; } /* Pause as all CPU's enter the NMI handler */ uv_nmi_wait(master); /* Process actions other than "kdump": */ - if (uv_nmi_action_is("health")) { + switch (uv_nmi_action) { + case nmi_act_health: uv_nmi_action_health(cpu, regs, master); - } else if (uv_nmi_action_is("ips") || uv_nmi_action_is("dump")) { + break; + case nmi_act_ips: + case nmi_act_dump: uv_nmi_dump_state(cpu, regs, master); - } else if (uv_nmi_action_is("kdb") || uv_nmi_action_is("kgdb")) { + break; + case nmi_act_kdb: + case nmi_act_kgdb: uv_call_kgdb_kdb(cpu, regs, master); - } else { + break; + default: if (master) - pr_alert("UV: unknown NMI action: %s\n", uv_nmi_action); + pr_alert("UV: unknown NMI action: %d\n", uv_nmi_action); uv_nmi_sync_exit(master); + break; } /* Clear per_cpu "in_nmi" flag */