Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933039AbaD1Vzm (ORCPT ); Mon, 28 Apr 2014 17:55:42 -0400 Received: from mail-vc0-f175.google.com ([209.85.220.175]:47892 "EHLO mail-vc0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753457AbaD1Vzl (ORCPT ); Mon, 28 Apr 2014 17:55:41 -0400 MIME-Version: 1.0 In-Reply-To: References: <535EA976.1080402@linux.vnet.ibm.com> Date: Mon, 28 Apr 2014 14:55:40 -0700 X-Google-Sender-Auth: uhktfIdJbqKlI2R2VDv85WIBLNM Message-ID: Subject: Re: [BUG] kernel BUG at mm/vmacache.c:85! From: Linus Torvalds To: "Srivatsa S. Bhat" Cc: Linux MM , "linux-kernel@vger.kernel.org" , Davidlohr Bueso , Rik van Riel , Michel Lespinasse , Hugh Dickins , "akpm@linux-foundation.org" 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 Mon, Apr 28, 2014 at 2:20 PM, Linus Torvalds wrote: > > That said, the bug does seem to be that some path doesn't invalidate > the vmacache sufficiently, or something inserts a vmacache entry into > the current process when looking up a remote process or whatever. > Davidlohr, ideas? Maybe we missed some use_mm() call. That will change the current mm without flushing the vma cache. The code considers kernel threads to be bad targets for vma caching for this reason (and perhaps others), but maybe we missed something. I wonder if we should just invalidate the vma cache in use_mm(), and remote the "kernel tasks are special" check. Srivatsa, are you doing something peculiar on that system that would trigger this? I see some kdump failures in the log, anything else? 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/