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=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, 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 31095C433ED for ; Mon, 26 Apr 2021 09:05:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F05F4611AE for ; Mon, 26 Apr 2021 09:05:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232181AbhDZJGY (ORCPT ); Mon, 26 Apr 2021 05:06:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:36532 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232068AbhDZJGX (ORCPT ); Mon, 26 Apr 2021 05:06:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E0BCC61001; Mon, 26 Apr 2021 09:05:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619427942; bh=RPVEzH89LdDz+18RiANymiSp2qhrJ+TwA0Z1Q0cns8w=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=zVBtfoXgAr8Wg8QdmWf9uoAMtSDyzGt6I2dOmPjVEG6X9Zlb+sI/eGA1jNV+xdQdE 2sWOxIWNSq4ftY+D7uLhc8SX+DV4N+7eGlD4iiGkV5qcuJJgN7GGhE1NsLezGAaZMd QwuQ+yoH70MyHQbSDgYcLOKMJICnzgyKpZjan/Xw= Date: Mon, 26 Apr 2021 11:05:39 +0200 From: Greg KH To: Hanjun Guo Cc: He Ying , patchwork@huawei.com, huawei.libin@huawei.com, yangerkun@huawei.com, xiexiuqi@huawei.com, Marc Zyngier , stable@vger.kernel.org Subject: Re: [PATCH hulk-4.19-next] irqchip/gic-v3: Do not enable irqs when handling spurious interrups Message-ID: References: <20210426023929.89400-1-heying24@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, Apr 26, 2021 at 04:44:45PM +0800, Hanjun Guo wrote: > On 2021/4/26 13:39, Greg KH wrote: > > On Sun, Apr 25, 2021 at 10:39:29PM -0400, He Ying wrote: > > > hulk inclusion > > > category: bugfix > > > bugzilla: NA > > > DTS: NA > > > CVE: NA > > > > > > -------------------------------- > > > > > > We triggered the following error while running our 4.19 kernel > > > with the pseudo-NMI patches backported to it: > > > > > > [ 14.816231] ------------[ cut here ]------------ > > > [ 14.816231] kernel BUG at irq.c:99! > > > [ 14.816232] Internal error: Oops - BUG: 0 [#1] SMP > > > [ 14.816232] Process swapper/0 (pid: 0, stack limit = 0x(____ptrval____)) > > > [ 14.816233] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G O 4.19.95.aarch64 #14 > > > [ 14.816233] Hardware name: evb (DT) > > > [ 14.816234] pstate: 80400085 (Nzcv daIf +PAN -UAO) > > > [ 14.816234] pc : asm_nmi_enter+0x94/0x98 > > > [ 14.816235] lr : asm_nmi_enter+0x18/0x98 > > > [ 14.816235] sp : ffff000008003c50 > > > [ 14.816235] pmr_save: 00000070 > > > [ 14.816237] x29: ffff000008003c50 x28: ffff0000095f56c0 > > > [ 14.816238] x27: 0000000000000000 x26: ffff000008004000 > > > [ 14.816239] x25: 00000000015e0000 x24: ffff8008fb916000 > > > [ 14.816240] x23: 0000000020400005 x22: ffff0000080817cc > > > [ 14.816241] x21: ffff000008003da0 x20: 0000000000000060 > > > [ 14.816242] x19: 00000000000003ff x18: ffffffffffffffff > > > [ 14.816243] x17: 0000000000000008 x16: 003d090000000000 > > > [ 14.816244] x15: ffff0000095ea6c8 x14: ffff8008fff5ab40 > > > [ 14.816244] x13: ffff8008fff58b9d x12: 0000000000000000 > > > [ 14.816245] x11: ffff000008c8a200 x10: 000000008e31fca5 > > > [ 14.816246] x9 : ffff000008c8a208 x8 : 000000000000000f > > > [ 14.816247] x7 : 0000000000000004 x6 : ffff8008fff58b9e > > > [ 14.816248] x5 : 0000000000000000 x4 : 0000000080000000 > > > [ 14.816249] x3 : 0000000000000000 x2 : 0000000080000000 > > > [ 14.816250] x1 : 0000000000120000 x0 : ffff0000095f56c0 > > > [ 14.816251] Call trace: > > > [ 14.816251] asm_nmi_enter+0x94/0x98 > > > [ 14.816251] el1_irq+0x8c/0x180 (IRQ C) > > > [ 14.816252] gic_handle_irq+0xbc/0x2e4 > > > [ 14.816252] el1_irq+0xcc/0x180 (IRQ B) > > > [ 14.816253] arch_timer_handler_virt+0x38/0x58 > > > [ 14.816253] handle_percpu_devid_irq+0x90/0x240 > > > [ 14.816253] generic_handle_irq+0x34/0x50 > > > [ 14.816254] __handle_domain_irq+0x68/0xc0 > > > [ 14.816254] gic_handle_irq+0xf8/0x2e4 > > > [ 14.816255] el1_irq+0xcc/0x180 (IRQ A) > > > [ 14.816255] arch_cpu_idle+0x34/0x1c8 > > > [ 14.816255] default_idle_call+0x24/0x44 > > > [ 14.816256] do_idle+0x1d0/0x2c8 > > > [ 14.816256] cpu_startup_entry+0x28/0x30 > > > [ 14.816256] rest_init+0xb8/0xc8 > > > [ 14.816257] start_kernel+0x4c8/0x4f4 > > > [ 14.816257] Code: 940587f1 d5384100 b9401001 36a7fd01 (d4210000) > > > [ 14.816258] Modules linked in: start_dp(O) smeth(O) > > > [ 15.103092] ---[ end trace 701753956cb14aa8 ]--- > > > [ 15.103093] Kernel panic - not syncing: Fatal exception in interrupt > > > [ 15.103099] SMP: stopping secondary CPUs > > > [ 15.103100] Kernel Offset: disabled > > > [ 15.103100] CPU features: 0x36,a2400218 > > > [ 15.103100] Memory Limit: none > > > > > > which is cause by a 'BUG_ON(in_nmi())' in nmi_enter(). > > > > > > >From the call trace, we can find three interrupts (noted A, B, C above): > > > interrupt (A) is preempted by (B), which is further interrupted by (C). > > > > > > Subsequent investigations show that (B) results in nmi_enter() being > > > called, but that it actually is a spurious interrupt. Furthermore, > > > interrupts are reenabled in the context of (B), and (C) fires with > > > NMI priority. We end-up with a nested NMI situation, something > > > we definitely do not want to (and cannot) handle. > > > > > > The bug here is that spurious interrupts should never result in any > > > state change, and we should just return to the interrupted context. > > > Moving the handling of spurious interrupts as early as possible in > > > the GICv3 handler fixes this issue. > > > > > > Fixes: 3f1f3234bc2d ("irqchip/gic-v3: Switch to PMR masking before calling IRQ handler") > > > > This commit is in 5.1, not 4.19. > > > > How are you hitting this? > > > > What are we supposed to do wit this patch? > > > > confused, > > Sorry for the noise, we have an internally used kernel which is based > on LTS 4.19 kernel, and we backported some mainline features including > the pseudo NMI for ARM64, that's why we backporting the following > bugfixes as well. > > I didn't notice it was cced stable and Marc as well, and adding > my review tag (for internally review process), sorry. Not a problem, thanks for letting us know. greg k-h