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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED670C433FE for ; Wed, 24 Nov 2021 07:46:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240129AbhKXHuA (ORCPT ); Wed, 24 Nov 2021 02:50:00 -0500 Received: from smtp-relay-internal-1.canonical.com ([185.125.188.123]:35906 "EHLO smtp-relay-internal-1.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234692AbhKXHt6 (ORCPT ); Wed, 24 Nov 2021 02:49:58 -0500 Received: from mail-oi1-f197.google.com (mail-oi1-f197.google.com [209.85.167.197]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-internal-1.canonical.com (Postfix) with ESMTPS id CC1603F32E for ; Wed, 24 Nov 2021 07:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1637740007; bh=41d8EvmewBk6qtYJvBs7XURC6hhNsnDFxi4IPnDanww=; h=MIME-Version:References:In-Reply-To:From:Date:Message-ID:Subject: To:Cc:Content-Type; b=UqR9c7oGNZXA0S+16xsqHErQy1ZBEAEVHTHa5iipMGhGydepEKgrltkMfiFJ+iULu 3WwFkXuFlltxV7mF5mB/ghnwQ1ibIpIkZYiaqDIFNI3eDZjCzoyPsA8yqIVRYr6/gQ S9aKqCCf01HpcM1CeN/C/wP877wKklD5DgoBoTVXnsnYXH/Cb04gxJ3hchCy8VGyeC /BUG2geueraudw39g+cJjXiu8P1xas3QHJWP6pfzq+HnG++E4e9WMZ7njRmXMFtsM2 wCR2UrJ1PRQaxUDSXG4GwMGDjAo0u6ntCqbX7jLKZ/2NXDByKT1ClkDP3K9uQ46/yY B7O3ON6JjpEMQ== Received: by mail-oi1-f197.google.com with SMTP id y21-20020aca4b15000000b002a819a3cd6dso1060125oia.15 for ; Tue, 23 Nov 2021 23:46:47 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=41d8EvmewBk6qtYJvBs7XURC6hhNsnDFxi4IPnDanww=; b=4J9FEz4hpsDz1ubyu47+CzyGc2boL4OqUR2eYgl7z1u5cAmzCYgYBVDvoGHT/YZWTS /tnpF7yM/GrIl9N5utrnuwvMzUdmKnuzFk/6rm/t6/5sQjSuPf8Kezc6kFl9XzdzO9W7 NrNjQKd6qpeooyCSab5pnNHj0xZ9XoYD4vkYoBp8DtuxpHDG/9B2+ZD0s35muS41SYc0 p3HgLb/KbMbuSqCaJDwTMIXPYiD/VJB/MGh8c7GjmpNgF37RKr1hYsjZV9RWiiO8XA32 CqRaHxoK6mKRnQYwn2N+0oXkpV2UYR2ESdb6Oec9uhmbar9AbvCoS1GGCU3YOu1nkw7O +oJQ== X-Gm-Message-State: AOAM5317R15wxZ7IR3ItGA8pyMrqKgkOOIVQmISyr7ySiyW4Qfz+6hTB 3UubYP1QwGRw7rvaFTCrMDB44vYiuqUcZdKe639nD2WryU3hf27nE9ulfl2Zo6lJyvbOFhYNVt/ hKFZDm7xEFAZiuAugTSfFie8W49BtTlnkPGTWCP90ou+ME5ViiynTNKYoHQ== X-Received: by 2002:aca:1a05:: with SMTP id a5mr4000793oia.146.1637740006601; Tue, 23 Nov 2021 23:46:46 -0800 (PST) X-Google-Smtp-Source: ABdhPJyM4ycPL4qVHt0LnBtJ22sU+UsiSnwmlB+8bqOrZLqMNyA/ppy7P3eLlCPtz2s+/0I7M+uGLxfmwYchcLstLQ8= X-Received: by 2002:aca:1a05:: with SMTP id a5mr4000767oia.146.1637740006367; Tue, 23 Nov 2021 23:46:46 -0800 (PST) MIME-Version: 1.0 References: <2611837.mvXUDI8C0e@kreacher> <5521509.DvuYhMxLoT@kreacher> In-Reply-To: <5521509.DvuYhMxLoT@kreacher> From: Kai-Heng Feng Date: Wed, 24 Nov 2021 15:46:34 +0800 Message-ID: Subject: Re: [PATCH v2] ACPI: CPPC: Add NULL pointer check to cppc_get_perf() To: "Rafael J. Wysocki" Cc: Linux ACPI , LKML , Linux PM , Srinivas Pandruvada Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 18, 2021 at 9:37 PM Rafael J. Wysocki wrote: > > From: Rafael J. Wysocki > Subject: [PATCH] ACPI: CPPC: Add NULL pointer check to cppc_get_perf() > > Check cpc_desc against NULL in cppc_get_perf(), so it doesn't crash > down the road if cpc_desc is NULL. > > Fixes: 0654cf05d17b ("ACPI: CPPC: Introduce cppc_get_nominal_perf()") > Reported-by: Kai-Heng Feng > Signed-off-by: Rafael J. Wysocki > Cc: 5.15+ # 5.15+ Sorry for the late test, I bricked my previous ADL rig. Tested-by: Kai-Heng Feng > --- > > -> v2: Check cpc_desc against NULL before using it to initialize reg. > > --- > drivers/acpi/cppc_acpi.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > Index: linux-pm/drivers/acpi/cppc_acpi.c > =================================================================== > --- linux-pm.orig/drivers/acpi/cppc_acpi.c > +++ linux-pm/drivers/acpi/cppc_acpi.c > @@ -998,7 +998,14 @@ static int cpc_write(int cpu, struct cpc > static int cppc_get_perf(int cpunum, enum cppc_regs reg_idx, u64 *perf) > { > struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum); > - struct cpc_register_resource *reg = &cpc_desc->cpc_regs[reg_idx]; > + struct cpc_register_resource *reg; > + > + if (!cpc_desc) { > + pr_debug("No CPC descriptor for CPU:%d\n", cpunum); > + return -ENODEV; > + } > + > + reg = &cpc_desc->cpc_regs[reg_idx]; > > if (CPC_IN_PCC(reg)) { > int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); > > >