From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Date: Fri, 20 Mar 2015 18:05:05 +0000 Subject: Re: 4.0.0-rc4: panic in free_block Message-Id: <550C6151.8070803@oracle.com> List-Id: References: <550C37C9.2060200@oracle.com> <550C5078.8040402@oracle.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds , linux-mm Cc: "David S. Miller" , LKML , sparclinux@vger.kernel.org On 3/20/15 10:58 AM, Linus Torvalds wrote: > That said, SLAB is probably also almost unheard of in high-CPU > configurations, since slub has all the magical unlocked lists etc for > scalability. So maybe it's a generic SLAB bug, and nobody with lots of > CPU's is testing SLAB. > Evidently, it is a well known problem internally that goes back to at least 2.6.39. To this point I have not paid attention to the allocators. At what point is SLUB considered stable for large systems? Is 2.6.39 stable? As for SLAB it is not clear if this is a sparc only problem. Perhaps the config should have a warning? It looks like SLAB is still the default for most arch. DaveM: do you mind if I submit a patch to change the default for sparc to SLUB? Now that the monster is unleashed, off to other problems... Thanks, David From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f177.google.com (mail-pd0-f177.google.com [209.85.192.177]) by kanga.kvack.org (Postfix) with ESMTP id 3539B6B0038 for ; Fri, 20 Mar 2015 14:07:01 -0400 (EDT) Received: by pdbop1 with SMTP id op1so115323126pdb.2 for ; Fri, 20 Mar 2015 11:07:00 -0700 (PDT) Received: from aserp1040.oracle.com (aserp1040.oracle.com. [141.146.126.69]) by mx.google.com with ESMTPS id ht3si10613261pdb.137.2015.03.20.11.05.51 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Fri, 20 Mar 2015 11:06:22 -0700 (PDT) Message-ID: <550C6151.8070803@oracle.com> Date: Fri, 20 Mar 2015 12:05:05 -0600 From: David Ahern MIME-Version: 1.0 Subject: Re: 4.0.0-rc4: panic in free_block References: <550C37C9.2060200@oracle.com> <550C5078.8040402@oracle.com> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Linus Torvalds , linux-mm Cc: "David S. Miller" , LKML , sparclinux@vger.kernel.org On 3/20/15 10:58 AM, Linus Torvalds wrote: > That said, SLAB is probably also almost unheard of in high-CPU > configurations, since slub has all the magical unlocked lists etc for > scalability. So maybe it's a generic SLAB bug, and nobody with lots of > CPU's is testing SLAB. > Evidently, it is a well known problem internally that goes back to at least 2.6.39. To this point I have not paid attention to the allocators. At what point is SLUB considered stable for large systems? Is 2.6.39 stable? As for SLAB it is not clear if this is a sparc only problem. Perhaps the config should have a warning? It looks like SLAB is still the default for most arch. DaveM: do you mind if I submit a patch to change the default for sparc to SLUB? Now that the monster is unleashed, off to other problems... Thanks, David -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751432AbbCTSGd (ORCPT ); Fri, 20 Mar 2015 14:06:33 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:24873 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750956AbbCTSGc (ORCPT ); Fri, 20 Mar 2015 14:06:32 -0400 Message-ID: <550C6151.8070803@oracle.com> Date: Fri, 20 Mar 2015 12:05:05 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Linus Torvalds , linux-mm CC: "David S. Miller" , LKML , sparclinux@vger.kernel.org Subject: Re: 4.0.0-rc4: panic in free_block References: <550C37C9.2060200@oracle.com> <550C5078.8040402@oracle.com> In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/20/15 10:58 AM, Linus Torvalds wrote: > That said, SLAB is probably also almost unheard of in high-CPU > configurations, since slub has all the magical unlocked lists etc for > scalability. So maybe it's a generic SLAB bug, and nobody with lots of > CPU's is testing SLAB. > Evidently, it is a well known problem internally that goes back to at least 2.6.39. To this point I have not paid attention to the allocators. At what point is SLUB considered stable for large systems? Is 2.6.39 stable? As for SLAB it is not clear if this is a sparc only problem. Perhaps the config should have a warning? It looks like SLAB is still the default for most arch. DaveM: do you mind if I submit a patch to change the default for sparc to SLUB? Now that the monster is unleashed, off to other problems... Thanks, David