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 X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC7C8C43461 for ; Tue, 8 Sep 2020 18:37:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFC4A2080C for ; Tue, 8 Sep 2020 18:37:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="QNOSICBK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731362AbgIHShe (ORCPT ); Tue, 8 Sep 2020 14:37:34 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:39126 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728572AbgIHSh2 (ORCPT ); Tue, 8 Sep 2020 14:37:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599590247; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4hFz93R/epUx5ygJCxi7aKlkiNQm5+bqKazJAau4MUY=; b=QNOSICBKCCkjT3z/L/0rfRzs4Nm+zR79po9yr+CpxkXMRft+y3zO4/fhyFR7dsUjbshS0Y 4FQ6wV8eOZTlSrDoA/LhI7QEbOlZI3RbeNvTxJI8gLczau3DYCmKmXFPKH3PYSB4o90rGB 6VFM1nO63Jn2DGqQJuETyJX3ClAw7GE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-510-KwvEnB2CMD-KkDvmAjm5DQ-1; Tue, 08 Sep 2020 14:37:25 -0400 X-MC-Unique: KwvEnB2CMD-KkDvmAjm5DQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 66DC9801AB2; Tue, 8 Sep 2020 18:37:23 +0000 (UTC) Received: from ovpn-112-26.rdu2.redhat.com (ovpn-112-26.rdu2.redhat.com [10.10.112.26]) by smtp.corp.redhat.com (Postfix) with ESMTP id C50EB282F0; Tue, 8 Sep 2020 18:37:22 +0000 (UTC) Message-ID: <489a7918b244e83736feff79c59a4b74d4e5cad0.camel@redhat.com> Subject: Re: [PATCH] drivers/perf: xgene_pmu: Fix uninitialized resource struct From: Mark Salter To: Will Deacon Cc: Mark Rutland , Khuong Dinh , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Date: Tue, 08 Sep 2020 14:37:22 -0400 In-Reply-To: <20200907135026.GC12551@willie-the-truck> References: <20200902182729.27415-1-msalter@redhat.com> <20200907135026.GC12551@willie-the-truck> Organization: Red Hat, Inc Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.3 (3.36.3-1.module_f32+9025+599b805f) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2020-09-07 at 14:50 +0100, Will Deacon wrote: > On Wed, Sep 02, 2020 at 02:27:29PM -0400, Mark Salter wrote: > > diff --git a/drivers/perf/xgene_pmu.c b/drivers/perf/xgene_pmu.c > > index edac28cd25dd..fdbbd0804b92 100644 > > --- a/drivers/perf/xgene_pmu.c > > +++ b/drivers/perf/xgene_pmu.c > > @@ -1483,6 +1483,7 @@ xgene_pmu_dev_ctx *acpi_get_pmu_hw_inf(struct xgene_pmu *xgene_pmu, > > return NULL; > > > > INIT_LIST_HEAD(&resource_list); > > + memset(&res, 0, sizeof(res)); > > rc = acpi_dev_get_resources(adev, &resource_list, > > acpi_pmu_dev_add_resource, &res); > > acpi_dev_free_resource_list(&resource_list); > > Hmm, to be honest, I'm not sure we should be calling devm_ioremap_resource() > at all here. The resource is clearly bogus, even with this change: the name > and the resource hierarchy pointers will all be NULL. I think it would be > better to follow the TX2 PMU driver (drivers/perf/thunderx2_pmu.c) which > appears to assign the resource directly in tx2_uncore_pmu_init_dev(). > > Is there a reason we can't do that? > > Will > There's no difference between xgene and tx2 wrt resouce name/hierarchy. They both call devm_ioresource_remap() which ends up setting the name and hierarchy. The difference is that xgene calls acpi_dev_resource_memory() directly from the acpi_dev_get_resources() callback. TX2 doesn't use such a callback and in that case, acpi_dev_resource_memory() gets called with a zeroed struct. That said, changing xgene to avoid the callback like TX2 does would fix the problem as well. If you'd rather go that route, I can send a patch for it. Mark