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 C5CB8C433B4 for ; Mon, 26 Apr 2021 05:40:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 99DFA6135F for ; Mon, 26 Apr 2021 05:40:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231839AbhDZFkl (ORCPT ); Mon, 26 Apr 2021 01:40:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:52626 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229517AbhDZFkk (ORCPT ); Mon, 26 Apr 2021 01:40:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5C06D61008; Mon, 26 Apr 2021 05:39:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619415599; bh=njr0Ysszeqni6GU93C2Jl9VAnXivePqk/JzT60r35Gk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dUNa9LeJJPti4JRdbcQbBld+iwbbbOqsO0AfL8Wa0mxdIP/eM5BhwBTEmvp17FcTK GslDQLDOBMyLyG3mazU4/2nUZ4ZPoelMye4eYUqIY0gB42LOUvTaM6BOwK40Bn9iBF rZ6wyxGwrHKL5VV8C2Kmaekn3BbCwEfy7YzdPEbs= Date: Mon, 26 Apr 2021 07:39:57 +0200 From: Greg KH To: He Ying Cc: patchwork@huawei.com, huawei.libin@huawei.com, yangerkun@huawei.com, xiexiuqi@huawei.com, guohanjun@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: <20210426023929.89400-1-heying24@huawei.com> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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, greg k-h