From nobody Tue Apr 7 04:58:33 2026 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 32370C433FE for ; Wed, 12 Oct 2022 08:20:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229640AbiJLIUw (ORCPT ); Wed, 12 Oct 2022 04:20:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229475AbiJLIUa (ORCPT ); Wed, 12 Oct 2022 04:20:30 -0400 Received: from mail-ej1-x631.google.com (mail-ej1-x631.google.com [IPv6:2a00:1450:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B1D2C5D0CE for ; Wed, 12 Oct 2022 01:19:32 -0700 (PDT) Received: by mail-ej1-x631.google.com with SMTP id r17so36369547eja.7 for ; Wed, 12 Oct 2022 01:19:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ventanamicro.com; s=google; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=dE/2qGYkUUnqJE7p+gf/1jfv6b0/ZXiraeAgOCSTCAw=; b=DBvsJD5mAClRAEjKGE5SN+H+mW3bLWszADIthuonbpvLiktT+6fYTnHjxmosZ4zSiP NQsYiSmWvu1H80GdUHnuV/Un4VX85t/EvNLHkwRo9+fhPQlGbUR5lBDtSaaft8xe4jnf rLQ8rfsFW6WdkjItZ+xb9xCp3Zp+3YUw+U2fHINsPgXL7ITN/6oJUG+Jg6jp0yHqAklH N6rDdGsjNA3JmKMKYbvSv9tJS96quK+8X7MMs4yCyIlzTDalP29sIeeb8uGTe3iH4bGW +f7+rJsEYEZAdElXMfY1Lb2MhouuPgojNNtAbPPGJRorUWMFGY9aSr4l7dLHTEBvSggZ iuwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=dE/2qGYkUUnqJE7p+gf/1jfv6b0/ZXiraeAgOCSTCAw=; b=VutIXsbmPSe/N7LqgUlIGdWfDxrSz5lv4s+vcTXTyxe9v3zwfoQE8qGOi7Im+CoWWe anjoaaM4uYULM/kmGDVXeW/rNqlvsCZO5UX80S+YZQQtJQNpvOOE/41XyCYQzRYK5uxm 8fAGtqN67llfgqMlM1RhH/3tGkCVkz69gac5m9eUvQySWjwsy4igOqpAbCc35jESm5Xz JoYTPZePjBqaHRXrv8iEeShYhi1ccjD8Jou9CoPPxcyBPvLNvzf3D0Vy54SUQOeFZobu EfivvpZUUxVOm6cIanY714YwKzXOoalKLIPTgTGiz78hAEpRhE2kQ4zM25C9q4EUMM3o m21Q== X-Gm-Message-State: ACrzQf3NpyecBnieAdRbXq83H8DVNRQlofMprh9DjIHYfQuXgMG2nmkq w9PZwwk3RECnTHPnsNhYY19JOg== X-Google-Smtp-Source: AMsMyM5zSPt7TGKtXNXuQD+Rz0OEiEViKIOyp+31JAL7p5w1LHIq/CuHS1uVMMxyaEdWjJ80spB0Mw== X-Received: by 2002:a17:906:58c9:b0:78d:b042:eecc with SMTP id e9-20020a17090658c900b0078db042eeccmr12367308ejs.658.1665562747414; Wed, 12 Oct 2022 01:19:07 -0700 (PDT) Received: from localhost (cst2-173-61.cust.vodafone.cz. [31.30.173.61]) by smtp.gmail.com with ESMTPSA id i24-20020a50d758000000b00458a03203b1sm10702867edj.31.2022.10.12.01.19.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Oct 2022 01:19:07 -0700 (PDT) From: Andrew Jones To: x86@kernel.org, linux-kernel@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Yury Norov Subject: [PATCH v2] x86: Fix /proc/cpuinfo cpumask warning Date: Wed, 12 Oct 2022 10:19:05 +0200 Message-Id: <20221012081905.1800640-1-ajones@ventanamicro.com> X-Mailer: git-send-email 2.37.3 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" Commit 78e5a3399421 ("cpumask: fix checking valid cpu range") has started issuing warnings[*] when cpu indices equal to nr_cpu_ids - 1 are passed to cpumask_next* functions. seq_read_iter() and cpuinfo's start and next seq operations implement a pattern like n =3D cpumask_next(n - 1, mask); show(n); while (1) { ++n; n =3D cpumask_next(n - 1, mask); if (n >=3D nr_cpu_ids) break; show(n); } which will issue the warning when reading /proc/cpuinfo. Ensure no warning is generated by validating the cpu index before calling cpumask_next(). [*] Warnings will only appear with DEBUG_PER_CPU_MAPS enabled. Signed-off-by: Andrew Jones Cc: Yury Norov --- arch/x86/kernel/cpu/proc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/cpu/proc.c b/arch/x86/kernel/cpu/proc.c index 099b6f0d96bd..94ac02c8dd6f 100644 --- a/arch/x86/kernel/cpu/proc.c +++ b/arch/x86/kernel/cpu/proc.c @@ -153,6 +153,9 @@ static int show_cpuinfo(struct seq_file *m, void *v) =20 static void *c_start(struct seq_file *m, loff_t *pos) { + if (*pos >=3D nr_cpu_ids) + return NULL; + *pos =3D cpumask_next(*pos - 1, cpu_online_mask); if ((*pos) < nr_cpu_ids) return &cpu_data(*pos); --=20 2.37.3