From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f171.google.com (mail-pd0-f171.google.com [209.85.192.171]) by kanga.kvack.org (Postfix) with ESMTP id E8C596B0069 for ; Thu, 27 Nov 2014 23:48:51 -0500 (EST) Received: by mail-pd0-f171.google.com with SMTP id y13so5987957pdi.2 for ; Thu, 27 Nov 2014 20:48:51 -0800 (PST) Received: from mailout3.samsung.com (mailout3.samsung.com. [203.254.224.33]) by mx.google.com with ESMTPS id c3si14506383pdk.33.2014.11.27.20.48.48 for (version=TLSv1 cipher=RC4-MD5 bits=128/128); Thu, 27 Nov 2014 20:48:50 -0800 (PST) Received: from epcpsbgm2.samsung.com (epcpsbgm2 [203.254.230.27]) by mailout3.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NFQ00IV1G1A6T90@mailout3.samsung.com> for linux-mm@kvack.org; Fri, 28 Nov 2014 13:48:46 +0900 (KST) From: Weijie Yang References: <1417144515812.18416@xiaomi.com> In-reply-to: <1417144515812.18416@xiaomi.com> Subject: RE: CMA, isolate: get warning in page_isolation.c:235 test_pages_isolated Date: Fri, 28 Nov 2014 12:48:00 +0800 Message-id: <000001d00ac6$97f829d0$c7e87d70$%yang@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=gb2312 Content-transfer-encoding: quoted-printable Content-language: zh-cn Sender: owner-linux-mm@kvack.org List-ID: To: =?gb2312?B?J9bsu9Qn?= , iamjoonsoo.kim@lge.com Cc: 'Hui Zhu' , linux-mm@kvack.org > -----Original Message----- > From: =D6=EC=BB=D4 [mailto:zhuhui@xiaomi.com] > Sent: Friday, November 28, 2014 11:15 AM > To: weijie.yang@samsung.com; iamjoonsoo.kim@lge.com > Cc: Hui Zhu; linux-mm@kvack.org > Subject: CMA, isolate: get warning in page_isolation.c:235 = test_pages_isolated >=20 > Hi guys, >=20 > After I back porting your patches: > mm/page_alloc: fix incorrect isolation behavior by rechecking = migratetype > mm/page_alloc: add freepage on isolate pageblock to correct buddy list > mm/page_alloc: move freepage counting logic to __free_one_page() > mm/page_alloc: restrict max order of merging on isolated pageblock > mm: page_alloc: store updated page migratetype to avoid misusing stale = value > mm: page_isolation: check pfn validity before access My patch is not proper, it doesn't consider the steal freepages in alloc = path. So it should be dropped(I will send a notice email to akpm). I am now working on its v2 patch and will resend it soon. Thanks > to 3.10 linux kernel. > I also use the CMA_AGGRESSIVE patches in = https://lkml.org/lkml/2014/10/15/623. >=20 > I got: > [68121.770699@2] ------------[ cut here ]------------ > [68121.774592@2] WARNING: at = /home/teawater/common/mm/page_isolation.c:235 = test_pages_isolated+0x108/0x208() > [68121.793911@2] CPU: 2 PID: 2711 Comm: kthread_xxx Tainted: P = O 3.10.33-250644-gcfd93f8-dirty #184 > [68121.803632@2] [] (unwind_backtrace+0x0/0x128) from = [] (show_stack+0x20/0x24) > [68121.812379@2] [] (show_stack+0x20/0x24) from [] = (dump_stack+0x20/0x28) > [68121.820612@2] [] (dump_stack+0x20/0x28) from [] = (warn_slowpath_common+0x5c/0x7c) > [68121.829712@2] [] (warn_slowpath_common+0x5c/0x7c) from = [] (warn_slowpath_null+0x2c/0x34) > [68121.839508@2] [] (warn_slowpath_null+0x2c/0x34) from = [] (test_pages_isolated+0x108/0x208) > [68121.849393@2] [] (test_pages_isolated+0x108/0x208) from = [] (alloc_contig_range+0x208/0x2b0) > [68121.859447@2] [] (alloc_contig_range+0x208/0x2b0) from = [] (dma_alloc_from_contiguous+0x15c/0x24c) >=20 > Looks it has some race issue between page isolation and free path = after these patches. > And I checked the free path but found nothing. >=20 > I worried that it still has some race issue between page isolation and = something in upstream. Or I missed some patches? > If we cannot handle this issue in a short time, I suggest add the = "move_freepages" code back to __test_page_isolated_in_pageblock. >=20 > Thanks, > Hui >=20 >=20 -- 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