From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f179.google.com (mail-lb0-f179.google.com [209.85.217.179]) by kanga.kvack.org (Postfix) with ESMTP id 7D6F96B0069 for ; Fri, 17 Oct 2014 07:12:13 -0400 (EDT) Received: by mail-lb0-f179.google.com with SMTP id l4so472809lbv.38 for ; Fri, 17 Oct 2014 04:12:12 -0700 (PDT) Received: from smtp1.it.da.ut.ee (mailhost6-1.ut.ee. [2001:bb8:2002:500::46]) by mx.google.com with ESMTP id l5si1578813lam.12.2014.10.17.04.12.10 for ; Fri, 17 Oct 2014 04:12:11 -0700 (PDT) Date: Fri, 17 Oct 2014 14:12:09 +0300 (EEST) From: Meelis Roos Subject: Re: unaligned accesses in SLAB etc. In-Reply-To: <20141016.165017.1151349565275102498.davem@davemloft.net> Message-ID: References: <20141016.160742.1639247937393238792.davem@redhat.com> <20141016.162001.599580415052560455.davem@redhat.com> <20141016.165017.1151349565275102498.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: David Miller Cc: iamjoonsoo.kim@lge.com, linux-kernel@vger.kernel.org, cl@linux.com, penberg@kernel.org, rientjes@google.com, akpm@linux-foundation.org, linux-mm@kvack.org, sparclinux@vger.kernel.org > From: David Miller > Date: Thu, 16 Oct 2014 16:20:01 -0400 (EDT) > > > So I'm going to audit all the code paths to make sure we don't put garbage > > into the fault_code value. > > There are two code paths where we can put garbage into the fault_code > value. And for the dtlb_prot.S case, the value we put in there is > TLB_TAG_ACCESS which is 0x30, which include bit 0x20 which is that > FAULT_CODE_BAD_RA indication which is erroneously triggering. > > The other path is via hugepage TLB misses, for the situation where > we haven't allocated the huge TSB for the thread yet. That might > explain some other longer-term problems we've had. > > I'm about to test the following fix: Thank you - it seems to work fine for me on E3500 on top of 3.17.0-07551-g052db7e + slab alignment fix. However, on top of mainline HEAD 3.17.0-09670-g0429fbc it explodes with scheduler BUG - just reported to LKML + sched maintainers. -- Meelis Roos (mroos@linux.ee) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org