From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752469Ab3FHQsj (ORCPT ); Sat, 8 Jun 2013 12:48:39 -0400 Received: from mail.skyhub.de ([78.46.96.112]:48479 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752212Ab3FHQsi (ORCPT ); Sat, 8 Jun 2013 12:48:38 -0400 From: Borislav Petkov To: X86 ML Cc: LKML , Borislav Petkov Subject: [PATCH] x86, intel_cacheinfo: Shut up last long-standing warning Date: Sat, 8 Jun 2013 18:48:15 +0200 Message-Id: <1370710095-20547-1-git-send-email-bp@alien8.de> X-Mailer: git-send-email 1.8.3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov arch/x86/kernel/cpu/intel_cacheinfo.c: In function ‘init_intel_cacheinfo’: arch/x86/kernel/cpu/intel_cacheinfo.c:642:28: warning: ‘this_leaf.size’ may be used uninitialized in this function [-Wmaybe-uninitialized] arch/x86/kernel/cpu/intel_cacheinfo.c:643:29: warning: ‘this_leaf.eax.split.num_threads_sharing’ may be used uninitialized in this function [-Wmaybe-uninitialized] This keeps on happening during randbuilds and the compiler is wrong here: In the case where cpuid4_cache_lookup_regs() returns 0, both this_leaf.size and this_leaf.eax get initialized. In the case where the CPUID leaf doesn't contain valid cache info, we error out which init_intel_cacheinfo() handles correctly without touching the abovementioned fields. So shut up the warning by clearing out the struct which we hand down. While at it, reverse error handling and gain one indentation level. Signed-off-by: Borislav Petkov --- arch/x86/kernel/cpu/intel_cacheinfo.c | 52 +++++++++++++++++------------------ 1 file changed, 25 insertions(+), 27 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c index 7c6f7d548c0f..8dc72dda66fe 100644 --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -618,36 +618,34 @@ unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c) * parameters cpuid leaf to find the cache details */ for (i = 0; i < num_cache_leaves; i++) { - struct _cpuid4_info_regs this_leaf; + struct _cpuid4_info_regs this_leaf = {}; int retval; retval = cpuid4_cache_lookup_regs(i, &this_leaf); - if (retval >= 0) { - switch (this_leaf.eax.split.level) { - case 1: - if (this_leaf.eax.split.type == - CACHE_TYPE_DATA) - new_l1d = this_leaf.size/1024; - else if (this_leaf.eax.split.type == - CACHE_TYPE_INST) - new_l1i = this_leaf.size/1024; - break; - case 2: - new_l2 = this_leaf.size/1024; - num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing; - index_msb = get_count_order(num_threads_sharing); - l2_id = c->apicid & ~((1 << index_msb) - 1); - break; - case 3: - new_l3 = this_leaf.size/1024; - num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing; - index_msb = get_count_order( - num_threads_sharing); - l3_id = c->apicid & ~((1 << index_msb) - 1); - break; - default: - break; - } + if (retval < 0) + continue; + + switch (this_leaf.eax.split.level) { + case 1: + if (this_leaf.eax.split.type == CACHE_TYPE_DATA) + new_l1d = this_leaf.size/1024; + else if (this_leaf.eax.split.type == CACHE_TYPE_INST) + new_l1i = this_leaf.size/1024; + break; + case 2: + new_l2 = this_leaf.size/1024; + num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing; + index_msb = get_count_order(num_threads_sharing); + l2_id = c->apicid & ~((1 << index_msb) - 1); + break; + case 3: + new_l3 = this_leaf.size/1024; + num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing; + index_msb = get_count_order(num_threads_sharing); + l3_id = c->apicid & ~((1 << index_msb) - 1); + break; + default: + break; } } } -- 1.8.3