Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753079AbaKZRhf (ORCPT ); Wed, 26 Nov 2014 12:37:35 -0500 Received: from mail-qc0-f171.google.com ([209.85.216.171]:47732 "EHLO mail-qc0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751012AbaKZRh0 (ORCPT ); Wed, 26 Nov 2014 12:37:26 -0500 MIME-Version: 1.0 In-Reply-To: <20141126143413.GA5876@redhat.com> References: <20141115213405.GA31971@redhat.com> <20141116014006.GA5016@redhat.com> <20141126002501.GA11752@redhat.com> <5475596A.9010301@suse.com> <54756424.6020409@suse.com> <20141126143413.GA5876@redhat.com> Date: Wed, 26 Nov 2014 09:37:25 -0800 X-Google-Sender-Auth: lDPYb4EI_qLWaT7XOXtjtrgr11U Message-ID: Subject: Re: frequent lockups in 3.18rc4 From: Linus Torvalds To: Dave Jones , Linus Torvalds , Juergen Gross , "the arch/x86 maintainers" , Kernel Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 26, 2014 at 6:34 AM, Dave Jones wrote: > > Woke up to the below trace. Looks like a different issue. Yeah, apparently the Xen issue was really just a Xen bug. > NMI watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [trinity-c149:24766] > RIP: 0010:[] [] kernel_map_pages+0xbc/0x120 Well, this one at least makes some amount of sense. The "Code:" line says it's 1b: 9c pushfq 1c: 5a pop %rdx 1d: fa cli 1e: 0f 20 e0 mov %cr4,%rax 21: 48 89 c1 mov %rax,%rcx 24: 80 e1 7f and $0x7f,%cl 27: 0f 22 e1 mov %rcx,%cr4 2a: 0f 22 e0 mov %rax,%cr4 2d: 52 push %rdx 2e: 9d popfq 2f:* eb cf jmp back <-- trapping instruction and %rdx is 0x0202 which is actually a valid flags value. That looks like the code for __native_flush_tlb_global(). Not that interrupt should have been disabled very long. > Call Trace: > [] get_page_from_freelist+0x49f/0xaa0 > [] __alloc_pages_nodemask+0x22e/0xb60 > [] alloc_pages_vma+0xee/0x1b0 > [] shmem_alloc_page+0x6e/0xc0 > [] shmem_getpage_gfp+0x4d0/0x7e0 > [] shmem_write_begin+0x42/0x70 > [] generic_perform_write+0xd4/0x1f0 > [] __generic_file_write_iter+0x162/0x350 > [] generic_file_write_iter+0x3f/0xb0 > [] do_iter_readv_writev+0x78/0xc0 > [] do_readv_writev+0xd8/0x2a0 > [] vfs_writev+0x3c/0x50 > [] SyS_writev+0x5c/0x100 > [] tracesys_phase2+0xd4/0xd9 Hmm. Maybe some oom issue, that we spent a long time before this trying to free pages? Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/