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=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 DCDD8C433DF for ; Fri, 3 Jul 2020 04:12:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C2EDD208C7 for ; Fri, 3 Jul 2020 04:12:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726163AbgGCEMG (ORCPT ); Fri, 3 Jul 2020 00:12:06 -0400 Received: from mail.loongson.cn ([114.242.206.163]:56276 "EHLO loongson.cn" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725294AbgGCEMF (ORCPT ); Fri, 3 Jul 2020 00:12:05 -0400 Received: from bogon.localdomain (unknown [113.200.148.30]) by mail.loongson.cn (Coremail) with SMTP id AQAAf9Dxj98OsP5eRPVOAA--.774S2; Fri, 03 Jul 2020 12:11:59 +0800 (CST) From: Xingxing Su To: Thomas Bogendoerfer , Huacai Chen , Jiaxun Yang Cc: linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, Xuefeng Li , Tiezhu Yang Subject: [PATCH] MIPS: Do not use smp_processor_id() in preemptible code Date: Fri, 3 Jul 2020 12:11:58 +0800 Message-Id: <1593749518-16722-1-git-send-email-suxingxing@loongson.cn> X-Mailer: git-send-email 2.1.0 X-CM-TRANSID: AQAAf9Dxj98OsP5eRPVOAA--.774S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJF4kuw17Ar4UKryfXFWDJwb_yoWrXw15pr 1UXr1UGr48Jr17Jr47try5Jr1UKF45A3W7JF1UJw1YqF1UWr1UJr18tFWUKr1DJry5Jry7 XryDtw4Utr1UGw7anT9S1TB71UUUUUDqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvj14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26r4j6ryUM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UM28EF7xvwVC2z280aVAFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r4j6F4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1l42xK82IYc2Ij64vI r41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1l4IxYO2xFxVAFwI0_Jrv_JF1lx2IqxVAqx4xG67 AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIY rxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14 v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWrJr0_WFyUJwCI42IY6I8E87Iv67AKxVWU JVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfU5s jjDUUUU X-CM-SenderInfo: pvx0x0xj0l0wo6or00hjvr0hdfq/1tbiAQAGC13QvL2z8gAAsB Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use preempt_disable() to fix the following bug under CONFIG_DEBUG_PREEMPT. [ 21.915305] BUG: using smp_processor_id() in preemptible [00000000] code: qemu-system-mip/1056 [ 21.923996] caller is do_ri+0x1d4/0x690 [ 21.927921] CPU: 0 PID: 1056 Comm: qemu-system-mip Not tainted 5.8.0-rc2 #3 [ 21.934913] Stack : 0000000000000001 ffffffff81370000 ffffffff8071cd60 a80f926d5ac95694 [ 21.942984] a80f926d5ac95694 0000000000000000 98000007f0043c88 ffffffff80f2fe40 [ 21.951054] 0000000000000000 0000000000000000 0000000000000001 0000000000000000 [ 21.959123] ffffffff802d60cc 98000007f0043dd8 ffffffff81f4b1e8 ffffffff81f60000 [ 21.967192] ffffffff81f60000 ffffffff80fe0000 ffff000000000000 0000000000000000 [ 21.975261] fffffffff500cce1 0000000000000001 0000000000000002 0000000000000000 [ 21.983331] ffffffff80fe1a40 0000000000000006 ffffffff8077f940 0000000000000000 [ 21.991401] ffffffff81460000 98000007f0040000 98000007f0043c80 000000fffba8cf20 [ 21.999471] ffffffff8071cd60 0000000000000000 0000000000000000 0000000000000000 [ 22.007541] 0000000000000000 0000000000000000 ffffffff80212ab4 a80f926d5ac95694 [ 22.015610] ... [ 22.018086] Call Trace: [ 22.020562] [] show_stack+0xa4/0x138 [ 22.025732] [] dump_stack+0xf0/0x150 [ 22.030903] [] check_preemption_disabled+0xf4/0x100 [ 22.037375] [] do_ri+0x1d4/0x690 [ 22.042198] [] handle_ri_int+0x44/0x5c [ 24.359386] BUG: using smp_processor_id() in preemptible [00000000] code: qemu-system-mip/1072 [ 24.368204] caller is do_ri+0x1a8/0x690 [ 24.372169] CPU: 4 PID: 1072 Comm: qemu-system-mip Not tainted 5.8.0-rc2 #3 [ 24.379170] Stack : 0000000000000001 ffffffff81370000 ffffffff8071cd60 a80f926d5ac95694 [ 24.387246] a80f926d5ac95694 0000000000000000 98001007ef06bc88 ffffffff80f2fe40 [ 24.395318] 0000000000000000 0000000000000000 0000000000000001 0000000000000000 [ 24.403389] ffffffff802d60cc 98001007ef06bdd8 ffffffff81f4b818 ffffffff81f60000 [ 24.411461] ffffffff81f60000 ffffffff80fe0000 ffff000000000000 0000000000000000 [ 24.419533] fffffffff500cce1 0000000000000001 0000000000000002 0000000000000000 [ 24.427603] ffffffff80fe0000 0000000000000006 ffffffff8077f940 0000000000000020 [ 24.435673] ffffffff81460020 98001007ef068000 98001007ef06bc80 000000fffbbbb370 [ 24.443745] ffffffff8071cd60 0000000000000000 0000000000000000 0000000000000000 [ 24.451816] 0000000000000000 0000000000000000 ffffffff80212ab4 a80f926d5ac95694 [ 24.459887] ... [ 24.462367] Call Trace: [ 24.464846] [] show_stack+0xa4/0x138 [ 24.470029] [] dump_stack+0xf0/0x150 [ 24.475208] [] check_preemption_disabled+0xf4/0x100 [ 24.481682] [] do_ri+0x1a8/0x690 [ 24.486509] [] handle_ri_int+0x44/0x5c Signed-off-by: Xingxing Su --- arch/mips/kernel/traps.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 7c32c95..a46ce94 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -723,12 +723,14 @@ static int simulate_loongson3_cpucfg(struct pt_regs *regs, perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); /* Do not emulate on unsupported core models. */ - if (!loongson3_cpucfg_emulation_enabled(¤t_cpu_data)) + preempt_disable(); + if (!loongson3_cpucfg_emulation_enabled(¤t_cpu_data)) { + preempt_enable(); return -1; - + } regs->regs[rd] = loongson3_cpucfg_read_synthesized( ¤t_cpu_data, sel); - + preempt_enable(); return 0; } -- 2.1.0