From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-3278546-1521213301-2-16101739794283807760 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='us-ascii' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521213300; b=Z+iruFb0OahRtzQCLOyru8A2L0HxrOGj2bUlQwermelNXVx HNSM453eNM3WVBggA2UqnW5CyznWekpIjzF0yT3L7HXzr8tBBkygvHf3EUd0CHdn a/qxCnLdXUdOxx6Pe574hw2H4nJ5+giAfAbL+NSqsoLg4OhJtU3AosR6Eb3V+1iV fZkoA/87Ioe9/mPFIIEk3Krgyf1Y+hg8Si+Si+WhbBrEcMotL1T8a17DEZSJ6+nq zWMV9DoyY226VTO3Jhlf/476iJcfSaejeAMfxD1QVZuxg9NeA1OXxZNWmjGkBatL beVfOA2uK09EzLnGpivZ5F/ZSQ5TgZH0mDjxMXw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=date:from:to:cc:subject:message-id :references:mime-version:content-type:in-reply-to:sender :list-id; s=arctest; t=1521213300; bh=dKsnjMTBUQIb3o0M0WErUYBYuw NpshEi/5wGMn3GJsU=; b=Xd3cryuJKaLPADlDpMOw6LPJgPcr130MuSJ4dX8uUe H3N0nPh9tG1qETzEsh+D6j0ExPgtvx3DZepehO4pK6Uc82P14cM/rf5bYj7wlYIX 2RwlycUABmx8UXmeOdiBT4H0ul/ZqKkc6ATC7pTUh8fKqtLA/PIC5KCeYo89wNGp AUqwWwox6k60TgrIqLlZAh5Whz4NR7LmIpof7ufwQ2Fzej/127ix2Ixm7KtA/LlP nMbpLax72rb37g9zqeyWLdSE/5yaegAT6vs2sjP8WMZIWr9Yp94lgfuoDAeUq29M EF2/L+REzwHvnTGVR9mcFc4IPBv4c1vCpI1l7x9qk/IA== ARC-Authentication-Results: i=1; mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes Authentication-Results: mx1.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=kernel.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=orgdomain_pass; x-category=clean score=-100 state=0; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=kernel.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751978AbeCPPOd (ORCPT ); Fri, 16 Mar 2018 11:14:33 -0400 Received: from mx2.suse.de ([195.135.220.15]:41222 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750748AbeCPPOd (ORCPT ); Fri, 16 Mar 2018 11:14:33 -0400 Date: Fri, 16 Mar 2018 16:14:30 +0100 From: Michal Hocko To: Daniel Vacek Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ard Biesheuvel , Andrew Morton , Vlastimil Babka , Mel Gorman , Pavel Tatashin , Paul Burton , stable@vger.kernel.org Subject: Re: [PATCH] Revert "mm: page_alloc: skip over regions of invalid pfns where possible" Message-ID: <20180316151430.GL23100@dhcp22.suse.cz> References: <20180316143855.29838-1-neelx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180316143855.29838-1-neelx@redhat.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Fri 16-03-18 15:38:55, Daniel Vacek wrote: > This reverts commit b92df1de5d289c0b5d653e72414bf0850b8511e0. The commit > is meant to be a boot init speed up skipping the loop in memmap_init_zone() > for invalid pfns. But given some specific memory mapping on x86_64 (or more > generally theoretically anywhere but on arm with CONFIG_HAVE_ARCH_PFN_VALID) > the implementation also skips valid pfns which is plain wrong and causes > 'kernel BUG at mm/page_alloc.c:1389!' > > crash> log | grep -e BUG -e RIP -e Call.Trace -e move_freepages_block -e rmqueue -e freelist -A1 > kernel BUG at mm/page_alloc.c:1389! > invalid opcode: 0000 [#1] SMP > -- > RIP: 0010:[] [] move_freepages+0x15e/0x160 > RSP: 0018:ffff88054d727688 EFLAGS: 00010087 > -- > Call Trace: > [] move_freepages_block+0x73/0x80 > [] __rmqueue+0x263/0x460 > [] get_page_from_freelist+0x7e1/0x9e0 > [] __alloc_pages_nodemask+0x176/0x420 > -- > RIP [] move_freepages+0x15e/0x160 > RSP > > crash> page_init_bug -v | grep RAM > 1000 - 9bfff System RAM (620.00 KiB) > 100000 - 430bffff System RAM ( 1.05 GiB = 1071.75 MiB = 1097472.00 KiB) > 4b0c8000 - 4bf9cfff System RAM ( 14.83 MiB = 15188.00 KiB) > 4bfac000 - 646b1fff System RAM (391.02 MiB = 400408.00 KiB) > 7b788000 - 7b7fffff System RAM (480.00 KiB) > 100000000 - 67fffffff System RAM ( 22.00 GiB) > > crash> page_init_bug | head -6 > 7b788000 - 7b7fffff System RAM (480.00 KiB) > 1fffff00000000 0 1 DMA32 4096 1048575 > 505736 505344 505855 > 0 0 0 DMA 1 4095 > 1fffff00000400 0 1 DMA32 4096 1048575 > BUG, zones differ! > > crash> kmem -p 77fff000 78000000 7b5ff000 7b600000 7b787000 7b788000 > PAGE PHYSICAL MAPPING INDEX CNT FLAGS > ffffea0001e00000 78000000 0 0 0 0 > ffffea0001ed7fc0 7b5ff000 0 0 0 0 > ffffea0001ed8000 7b600000 0 0 0 0 <<<< > ffffea0001ede1c0 7b787000 0 0 0 0 > ffffea0001ede200 7b788000 0 0 1 1fffff00000000 > > Fixes: b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") > Signed-off-by: Daniel Vacek > Acked-by: Ard Biesheuvel > Cc: Andrew Morton > Cc: Michal Hocko > Cc: Vlastimil Babka > Cc: Mel Gorman > Cc: Pavel Tatashin > Cc: Paul Burton > Cc: stable@vger.kernel.org Yes, this looks like the most simple way for now before a proper solution is found Acked-by: Michal Hocko > --- > include/linux/memblock.h | 1 - > mm/memblock.c | 28 ---------------------------- > mm/page_alloc.c | 11 +---------- > 3 files changed, 1 insertion(+), 39 deletions(-) > > diff --git a/include/linux/memblock.h b/include/linux/memblock.h > index 8be5077efb5f..f92ea7783652 100644 > --- a/include/linux/memblock.h > +++ b/include/linux/memblock.h > @@ -187,7 +187,6 @@ int memblock_search_pfn_nid(unsigned long pfn, unsigned long *start_pfn, > unsigned long *end_pfn); > void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn, > unsigned long *out_end_pfn, int *out_nid); > -unsigned long memblock_next_valid_pfn(unsigned long pfn, unsigned long max_pfn); > > /** > * for_each_mem_pfn_range - early memory pfn range iterator > diff --git a/mm/memblock.c b/mm/memblock.c > index b6ba6b7adadc..48376bd33274 100644 > --- a/mm/memblock.c > +++ b/mm/memblock.c > @@ -1101,34 +1101,6 @@ void __init_memblock __next_mem_pfn_range(int *idx, int nid, > *out_nid = r->nid; > } > > -unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn, > - unsigned long max_pfn) > -{ > - struct memblock_type *type = &memblock.memory; > - unsigned int right = type->cnt; > - unsigned int mid, left = 0; > - phys_addr_t addr = PFN_PHYS(++pfn); > - > - do { > - mid = (right + left) / 2; > - > - if (addr < type->regions[mid].base) > - right = mid; > - else if (addr >= (type->regions[mid].base + > - type->regions[mid].size)) > - left = mid + 1; > - else { > - /* addr is within the region, so pfn is valid */ > - return pfn; > - } > - } while (left < right); > - > - if (right == type->cnt) > - return -1UL; > - else > - return PHYS_PFN(type->regions[right].base); > -} > - > /** > * memblock_set_node - set node ID on memblock regions > * @base: base of area to set node ID for > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index 635d7dd29d7f..e4566a3f8083 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -5356,17 +5356,8 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, > if (context != MEMMAP_EARLY) > goto not_early; > > - if (!early_pfn_valid(pfn)) { > -#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP > - /* > - * Skip to the pfn preceding the next valid one (or > - * end_pfn), such that we hit a valid pfn (or end_pfn) > - * on our next iteration of the loop. > - */ > - pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1; > -#endif > + if (!early_pfn_valid(pfn)) > continue; > - } > if (!early_pfn_in_nid(pfn, nid)) > continue; > if (!update_defer_init(pgdat, pfn, end_pfn, &nr_initialised)) > -- > 2.16.2 > -- Michal Hocko SUSE Labs