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,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 1871FC07E96 for ; Thu, 8 Jul 2021 13:03:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DD4B461584 for ; Thu, 8 Jul 2021 13:03:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231433AbhGHNG3 (ORCPT ); Thu, 8 Jul 2021 09:06:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230396AbhGHNG2 (ORCPT ); Thu, 8 Jul 2021 09:06:28 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2B8DC061574; Thu, 8 Jul 2021 06:03:46 -0700 (PDT) From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1625749425; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MRfCbrQnCjc31mun5+lwwycjoViRgOB/BMNUJ5+WFVM=; b=XqHv15B4IzUHDb3aeRgQ9sUauMXSuWJTTUoBLFBg7gfNpqSdZz+HCXNTrRDVU1Hs3lihnx JANDD+V7ccrDsoSGZXo307eDImgnyvANXm0IZz3nwgiSjCqAUWuCMMg9tx6667WyaZF53b QU+hi4vZKSV2MRfp7E1o73tvD1CsOuSdsp/HsqCbe6wvkWcbxqTyBbNODiQIPdr3zDI8xo LLjpGBPv93PD9rzuHIOJrcPSCFdDgKCf5Tit7ww64Vg3jhXI1sTNIbgfzO1tu+btaeikY3 BgkBZMnh6EACv5LXSbZuZsm7z6ct3YEp6uBGDZmmVtJ/Q2c3OWv9jHo3y4PEmg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1625749425; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MRfCbrQnCjc31mun5+lwwycjoViRgOB/BMNUJ5+WFVM=; b=x5+ZjaUMukMtoLsi6pswazdqA74YMyQ4LYDTz12q7iwjXG7PC589ioXdFo3oGf5Lm6/oqS X39v/oanHo5CqlBQ== To: syzbot , akpm@linux-foundation.org, bp@alien8.de, hpa@zytor.com, jmattson@google.com, joro@8bytes.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, mark.rutland@arm.com, masahiroy@kernel.org, mingo@redhat.com, pbonzini@redhat.com, peterz@infradead.org, rafael.j.wysocki@intel.com, rostedt@goodmis.org, seanjc@google.com, sedat.dilek@gmail.com, syzkaller-bugs@googlegroups.com, vitor@massaru.org, vkuznets@redhat.com, wanpengli@tencent.com, will@kernel.org, x86@kernel.org Subject: Re: [syzbot] general protection fault in try_grab_compound_head In-Reply-To: <0000000000009e89e205c63dda94@google.com> References: <0000000000009e89e205c63dda94@google.com> Date: Thu, 08 Jul 2021 15:03:45 +0200 Message-ID: <87fswpot3i.ffs@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Sat, Jul 03 2021 at 13:24, syzbot wrote: > syzbot has bisected this issue to: > > commit 997acaf6b4b59c6a9c259740312a69ea549cc684 > Author: Mark Rutland > Date: Mon Jan 11 15:37:07 2021 +0000 > > lockdep: report broken irq restoration That's the commit which makes the underlying problem visible: raw_local_irq_restore() called with IRQs enabled and is triggered by this call chain: kvm_wait arch/x86/kernel/kvm.c:860 [inline] kvm_wait+0xc3/0xe0 arch/x86/kernel/kvm.c:837 pv_wait arch/x86/include/asm/paravirt.h:564 [inline] pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline] __pv_queued_spin_lock_slowpath+0x8b8/0xb40 kernel/locking/qspinlock.c:508 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:554 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:113 spin_lock include/linux/spinlock.h:354 [inline] alloc_huge_page+0x2b0/0xda0 mm/hugetlb.c:2318 hugetlb_no_page mm/hugetlb.c:4323 [inline] hugetlb_fault+0xc35/0x1cd0 mm/hugetlb.c:4523 follow_hugetlb_page+0x317/0xda0 mm/hugetlb.c:4836 __get_user_pages+0x3fa/0xe30 mm/gup.c:1041 __get_user_pages_locked mm/gup.c:1256 [inline] __gup_longterm_locked+0x15f/0xc80 mm/gup.c:1667 io_sqe_buffer_register fs/io_uring.c:8462 [inline] __io_uring_register fs/io_uring.c:9901 [inline] __do_sys_io_uring_register+0xeb1/0x3350 fs/io_uring.c:10000 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Thanks, tglx