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 25878C05027 for ; Wed, 8 Feb 2023 12:59:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231324AbjBHM7V convert rfc822-to-8bit (ORCPT ); Wed, 8 Feb 2023 07:59:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230262AbjBHM7R (ORCPT ); Wed, 8 Feb 2023 07:59:17 -0500 Received: from outpost1.zedat.fu-berlin.de (outpost1.zedat.fu-berlin.de [130.133.4.66]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C8311FF08; Wed, 8 Feb 2023 04:59:03 -0800 (PST) Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost.zedat.fu-berlin.de (Exim 4.95) with esmtps (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1pPk2F-002T4M-JL; Wed, 08 Feb 2023 13:58:51 +0100 Received: from p57bd9464.dip0.t-ipconnect.de ([87.189.148.100] helo=[192.168.178.81]) by inpost2.zedat.fu-berlin.de (Exim 4.95) with esmtpsa (TLS1.3) tls TLS_AES_256_GCM_SHA384 (envelope-from ) id 1pPk2F-000LfL-Bn; Wed, 08 Feb 2023 13:58:51 +0100 Message-ID: <3a5a4bee5c0739a3b988a328376a6eed3c385fda.camel@physik.fu-berlin.de> Subject: Re: [PATCH V2 3/3] SH: cpuinfo: Fix a warning for CONFIG_CPUMASK_OFFSTACK From: John Paul Adrian Glaubitz To: Huacai Chen , Arnd Bergmann , Thomas Bogendoerfer , Yoshinori Sato , Rich Felker Cc: loongarch@lists.linux.dev, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Huacai Chen , Guo Ren , Xuerui Wang , Jiaxun Yang , linux-mips@vger.kernel.org, linux-sh@vger.kernel.org, stable@vger.kernel.org Date: Wed, 08 Feb 2023 13:58:50 +0100 In-Reply-To: <20220714084136.570176-3-chenhuacai@loongson.cn> References: <20220714084136.570176-1-chenhuacai@loongson.cn> <20220714084136.570176-3-chenhuacai@loongson.cn> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT User-Agent: Evolution 3.46.3 MIME-Version: 1.0 X-Original-Sender: glaubitz@physik.fu-berlin.de X-Originating-IP: 87.189.148.100 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2022-07-14 at 16:41 +0800, Huacai Chen wrote: > When CONFIG_CPUMASK_OFFSTACK and CONFIG_DEBUG_PER_CPU_MAPS is selected, > cpu_max_bits_warn() generates a runtime warning similar as below while > we show /proc/cpuinfo. Fix this by using nr_cpu_ids (the runtime limit) > instead of NR_CPUS to iterate CPUs. > > [ 3.052463] ------------[ cut here ]------------ > [ 3.059679] WARNING: CPU: 3 PID: 1 at include/linux/cpumask.h:108 show_cpuinfo+0x5e8/0x5f0 > [ 3.070072] Modules linked in: efivarfs autofs4 > [ 3.076257] CPU: 0 PID: 1 Comm: systemd Not tainted 5.19-rc5+ #1052 > [ 3.099465] Stack : 9000000100157b08 9000000000f18530 9000000000cf846c 9000000100154000 > [ 3.109127] 9000000100157a50 0000000000000000 9000000100157a58 9000000000ef7430 > [ 3.118774] 90000001001578e8 0000000000000040 0000000000000020 ffffffffffffffff > [ 3.128412] 0000000000aaaaaa 1ab25f00eec96a37 900000010021de80 900000000101c890 > [ 3.138056] 0000000000000000 0000000000000000 0000000000000000 0000000000aaaaaa > [ 3.147711] ffff8000339dc220 0000000000000001 0000000006ab4000 0000000000000000 > [ 3.157364] 900000000101c998 0000000000000004 9000000000ef7430 0000000000000000 > [ 3.167012] 0000000000000009 000000000000006c 0000000000000000 0000000000000000 > [ 3.176641] 9000000000d3de08 9000000001639390 90000000002086d8 00007ffff0080286 > [ 3.186260] 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1c > [ 3.195868] ... > [ 3.199917] Call Trace: > [ 3.203941] [<90000000002086d8>] show_stack+0x38/0x14c > [ 3.210666] [<9000000000cf846c>] dump_stack_lvl+0x60/0x88 > [ 3.217625] [<900000000023d268>] __warn+0xd0/0x100 > [ 3.223958] [<9000000000cf3c90>] warn_slowpath_fmt+0x7c/0xcc > [ 3.231150] [<9000000000210220>] show_cpuinfo+0x5e8/0x5f0 > [ 3.238080] [<90000000004f578c>] seq_read_iter+0x354/0x4b4 > [ 3.245098] [<90000000004c2e90>] new_sync_read+0x17c/0x1c4 > [ 3.252114] [<90000000004c5174>] vfs_read+0x138/0x1d0 > [ 3.258694] [<90000000004c55f8>] ksys_read+0x70/0x100 > [ 3.265265] [<9000000000cfde9c>] do_syscall+0x7c/0x94 > [ 3.271820] [<9000000000202fe4>] handle_syscall+0xc4/0x160 > [ 3.281824] ---[ end trace 8b484262b4b8c24c ]--- > > Cc: stable@vger.kernel.org > Signed-off-by: Huacai Chen > --- > arch/sh/kernel/cpu/proc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/sh/kernel/cpu/proc.c b/arch/sh/kernel/cpu/proc.c > index a306bcd6b341..5f6d0e827bae 100644 > --- a/arch/sh/kernel/cpu/proc.c > +++ b/arch/sh/kernel/cpu/proc.c > @@ -132,7 +132,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) > > static void *c_start(struct seq_file *m, loff_t *pos) > { > - return *pos < NR_CPUS ? cpu_data + *pos : NULL; > + return *pos < nr_cpu_ids ? cpu_data + *pos : NULL; > } > static void *c_next(struct seq_file *m, void *v, loff_t *pos) > { I build-tested the patch and also booted the patched kernel successfully on my SH-7785LCR board. Showing the contents of /proc/cpuinfo works fine, too: root@tirpitz:~> cat /proc/cpuinfo machine : SH7785LCR processor : 0 cpu family : sh4a cpu type : SH7785 cut : 7.x cpu flags : fpu perfctr llsc cache type : split (harvard) icache size : 32KiB (4-way) dcache size : 32KiB (4-way) address sizes : 32 bits physical bogomips : 599.99 root@tirpitz:~> Tested-by: John Paul Adrian Glaubitz I am not sure yet whether the change is also correct as I don't know whether it's possible to change the number of CPUs at runtime on SuperH. Adrian -- .''`. John Paul Adrian Glaubitz : :' : Debian Developer `. `' Physicist `- GPG: 62FF 8A75 84E0 2956 9546 0006 7426 3B37 F5B5 F913