From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH 07/14] proc/kcore: hide a harmless warning Date: Fri, 14 Jul 2017 11:25:19 +0200 Message-ID: <20170714092540.1217397-8-arnd@arndb.de> References: <20170714092540.1217397-1-arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20170714092540.1217397-1-arnd@arndb.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: linux-kernel@vger.kernel.org, Jiri Olsa Cc: Pratyush Anand , Kees Cook , Arnd Bergmann , Ard Biesheuvel , Greg Kroah-Hartman , dri-devel@lists.freedesktop.org, linux-ide@vger.kernel.org, Tejun Heo , akpm@linux-foundation.org, Linus Torvalds , Ingo Molnar , Guenter Roeck , linux-media@vger.kernel.org List-Id: linux-ide@vger.kernel.org Z2NjIHdhcm5zIHdoZW4gTU9EVUxFU19WQUREUi9FTkQgaXMgZGVmaW5lZCB0byB0aGUgc2FtZSB2 YWx1ZSBhcwpWTUFMTE9DX1NUQVJUL1ZNQUxMT0NfRU5ELCBlLmcuIG9uIHg4Ni0zMjoKCmZzL3By b2Mva2NvcmUuYzogSW4gZnVuY3Rpb24g4oCYYWRkX21vZHVsZXNfcmFuZ2XigJk6CmZzL3Byb2Mv a2NvcmUuYzo2MjI6MTYxOiBlcnJvcjogc2VsZi1jb21wYXJpc29uIGFsd2F5cyBldmFsdWF0ZXMg dG8gZmFsc2UgWy1XZXJyb3I9dGF1dG9sb2dpY2FsLWNvbXBhcmVdCiAgaWYgKC8qTU9EVUxFU19W QUREUiAhPSBWTUFMTE9DX1NUQVJUICYmICovTU9EVUxFU19FTkQgIT0gVk1BTExPQ19FTkQpIHsK ClRoZSBjb2RlIGlzIGNvcnJlY3QgYXMgaXQgaXMgcmVxdWlyZWQgZm9yIG1vc3Qgb3RoZXIgY29u ZmlndXJhdGlvbnMuClRoZSBiZXN0IHdvcmthcm91bmQgSSBmb3VuZCBmb3Igc2h1dHRpbmcgdXAg dGhhdCB3YXJuaW5nIGlzIHRvIG1ha2UKaXQgYSBsaXR0bGUgbW9yZSBjb21wbGV4IGJ5IGFkZGlu ZyBhIHRlbXBvcmFyeSB2YXJpYWJsZS4gVGhlIGNvbXBpbGVyCndpbGwgc3RpbGwgb3B0aW1pemUg YXdheSB0aGUgY29kZSBhcyBpdCBmaW5kcyB0aGUgdHdvIHRvIGJlIGlkZW50aWNhbCwKYnV0IGl0 IG5vIGxvbmdlciB3YXJucyBiZWNhdXNlIGl0IGRvZXNuJ3QgY29uZGlkZXIgdGhlIGNvbXBhcmlz b24KInRhdXRvbG9naWNhbCIgYW55IG1vcmUuCgpTaWduZWQtb2ZmLWJ5OiBBcm5kIEJlcmdtYW5u IDxhcm5kQGFybmRiLmRlPgotLS0KIGZzL3Byb2Mva2NvcmUuYyB8IDEwICsrKysrKy0tLS0KIDEg ZmlsZSBjaGFuZ2VkLCA2IGluc2VydGlvbnMoKyksIDQgZGVsZXRpb25zKC0pCgpkaWZmIC0tZ2l0 IGEvZnMvcHJvYy9rY29yZS5jIGIvZnMvcHJvYy9rY29yZS5jCmluZGV4IDQ1NjI5ZjRiNTQwMi4u YzUwM2FkNjU3YzQ2IDEwMDY0NAotLS0gYS9mcy9wcm9jL2tjb3JlLmMKKysrIGIvZnMvcHJvYy9r Y29yZS5jCkBAIC02MjAsMTIgKzYyMCwxNCBAQCBzdGF0aWMgdm9pZCBfX2luaXQgcHJvY19rY29y ZV90ZXh0X2luaXQodm9pZCkKIC8qCiAgKiBNT0RVTEVTX1ZBRERSIGhhcyBubyBpbnRlcnNlY3Rp b24gd2l0aCBWTUFMTE9DX0FERFIuCiAgKi8KLXN0cnVjdCBrY29yZV9saXN0IGtjb3JlX21vZHVs ZXM7CitzdGF0aWMgc3RydWN0IGtjb3JlX2xpc3Qga2NvcmVfbW9kdWxlczsKIHN0YXRpYyB2b2lk IF9faW5pdCBhZGRfbW9kdWxlc19yYW5nZSh2b2lkKQogewotCWlmIChNT0RVTEVTX1ZBRERSICE9 IFZNQUxMT0NfU1RBUlQgJiYgTU9EVUxFU19FTkQgIT0gVk1BTExPQ19FTkQpIHsKLQkJa2NsaXN0 X2FkZCgma2NvcmVfbW9kdWxlcywgKHZvaWQgKilNT0RVTEVTX1ZBRERSLAotCQkJTU9EVUxFU19F TkQgLSBNT0RVTEVTX1ZBRERSLCBLQ09SRV9WTUFMTE9DKTsKKwl2b2lkICpzdGFydCA9ICh2b2lk ICopTU9EVUxFU19WQUREUjsKKwlzaXplX3QgbGVuID0gTU9EVUxFU19FTkQgLSBNT0RVTEVTX1ZB RERSOworCisJaWYgKHN0YXJ0ICE9ICh2b2lkICopVk1BTExPQ19TVEFSVCAmJiBsZW4gIT0gVk1B TExPQ19FTkQgLSBWTUFMTE9DX1NUQVJUKSB7CisJCWtjbGlzdF9hZGQoJmtjb3JlX21vZHVsZXMs IHN0YXJ0LCBsZW4sIEtDT1JFX1ZNQUxMT0MpOwogCX0KIH0KICNlbHNlCi0tIAoyLjkuMAoKX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVsIG1h aWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMu ZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753812AbdGNJ30 (ORCPT ); Fri, 14 Jul 2017 05:29:26 -0400 Received: from mout.kundenserver.de ([217.72.192.74]:62117 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753492AbdGNJ3T (ORCPT ); Fri, 14 Jul 2017 05:29:19 -0400 From: Arnd Bergmann To: linux-kernel@vger.kernel.org, Jiri Olsa Cc: Greg Kroah-Hartman , Linus Torvalds , Tejun Heo , Guenter Roeck , linux-ide@vger.kernel.org, linux-media@vger.kernel.org, akpm@linux-foundation.org, dri-devel@lists.freedesktop.org, Arnd Bergmann , Kees Cook , Ingo Molnar , Laura Abbott , Pratyush Anand , Ard Biesheuvel Subject: [PATCH 07/14] proc/kcore: hide a harmless warning Date: Fri, 14 Jul 2017 11:25:19 +0200 Message-Id: <20170714092540.1217397-8-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 In-Reply-To: <20170714092540.1217397-1-arnd@arndb.de> References: <20170714092540.1217397-1-arnd@arndb.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Provags-ID: V03:K0:ghCtubTquugxYj8GXBf21w0WF6x6A7m1oGb4vIk2ntS06+UzIB7 6rSzAPq4SiIApfV4cpU6NyXP3Lms3VmwqLd02hu5oG8f9aBijH3E7GPqdnd0D/tRxFZ1B7O mufbTLejE0GUH25bXTY4+iJRQq9yyK+RLzpSTzIMRUSoG7Awnhh1Ki4r6cvqJhnWQCj5jK6 OG1uvXkfoIQensG4aEkNg== X-UI-Out-Filterresults: notjunk:1;V01:K0:REZFiXnP75U=:QZwO4+FWBmB5fJGgVtJAmK QMxqjeknBVgUZ4ccWWGvHi3vgPcQrS7LICvNYSdg/1GSkAZ/51b2BVWaM0Bv2XWbggrITk4jL toVt7XqPzBvQRJEWK8cJeeAwAeWpboQ4Us4Pt16cL8jfDHOarruueiTt2lV8fiVFlib67u8SP wXeva3XyP7IzKno9Qtxu0yBOhsgGaqA55gFBiBko9WGgeMqSlYfG8IrWW2alUJ1ZR2KnvP0aC KMp1t6m76DYRqbebZx22VTmn+vYa88lcsGipB3YMBnliZiQZswz8lelgyq0D1jTGiKGKCL4ic Rtlayygx1DV2cdny4TY6aWbOb49OsQj117vox635BsTNtWFklepnAbgIImRKN9x1tyjyoWGHh 8j0qIho8amkwuBLMc4HCG5PxdqPn+A7r4rg3ro46pTnwBG4jLtwkRc5FkmFTnHOuaWvdjVXVY t7cn+qqwzQcISu2a6JVmIfuknRW7i65Tq4gDxv28mq3t1vaSZ9IBZLRV1nLytX3aNb5K8JTpS FmeXhDhxaIUdNwwyXnjid32kQ/kf6/X1v/dCWEuc2AhIZ9rylZj6wz6Y84XcpwLz8Nh44AU+R bz7W6r0adv6voPGOYlOJ4N93V7yrrkXZx39uQk0HE0/wuWVf/5JWs4XzV6cOvBHk7GWLVIZlU fR6V/MUzAUYAnYdKP0wutv0ayO2AOUlF5MYXxH9H07JhwDW4Cts+rpJg3SnSbDP8tzDEbaj/u YfBknCWKcPY4HkprEUI4wCEEiOL1iFMEbvZK6WbIH040xortuULl0JdcJMI= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org gcc warns when MODULES_VADDR/END is defined to the same value as VMALLOC_START/VMALLOC_END, e.g. on x86-32: fs/proc/kcore.c: In function ‘add_modules_range’: fs/proc/kcore.c:622:161: error: self-comparison always evaluates to false [-Werror=tautological-compare] if (/*MODULES_VADDR != VMALLOC_START && */MODULES_END != VMALLOC_END) { The code is correct as it is required for most other configurations. The best workaround I found for shutting up that warning is to make it a little more complex by adding a temporary variable. The compiler will still optimize away the code as it finds the two to be identical, but it no longer warns because it doesn't condider the comparison "tautological" any more. Signed-off-by: Arnd Bergmann --- fs/proc/kcore.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 45629f4b5402..c503ad657c46 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -620,12 +620,14 @@ static void __init proc_kcore_text_init(void) /* * MODULES_VADDR has no intersection with VMALLOC_ADDR. */ -struct kcore_list kcore_modules; +static struct kcore_list kcore_modules; static void __init add_modules_range(void) { - if (MODULES_VADDR != VMALLOC_START && MODULES_END != VMALLOC_END) { - kclist_add(&kcore_modules, (void *)MODULES_VADDR, - MODULES_END - MODULES_VADDR, KCORE_VMALLOC); + void *start = (void *)MODULES_VADDR; + size_t len = MODULES_END - MODULES_VADDR; + + if (start != (void *)VMALLOC_START && len != VMALLOC_END - VMALLOC_START) { + kclist_add(&kcore_modules, start, len, KCORE_VMALLOC); } } #else -- 2.9.0