linux-kernel - Re: [PATCH 08/13] mm, compaction: skip over holes in __reset_isolation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170427075922.GC4706@dhcp22.suse.cz>
Date:   Thu, 27 Apr 2017 09:59:22 +0200
From:   Michal Hocko <mhocko@...nel.org>
To:     linux-mm@...ck.org
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Mel Gorman <mgorman@...e.de>, Vlastimil Babka <vbabka@...e.cz>,
        Andrea Arcangeli <aarcange@...hat.com>,
        Jerome Glisse <jglisse@...hat.com>,
        Reza Arbab <arbab@...ux.vnet.ibm.com>,
        Yasuaki Ishimatsu <yasu.isimatu@...il.com>,
        qiuxishi@...wei.com, Kani Toshimitsu <toshi.kani@....com>,
        slaoub@...il.com, Joonsoo Kim <js1304@...il.com>,
        Andi Kleen <ak@...ux.intel.com>,
        David Rientjes <rientjes@...gle.com>,
        Daniel Kiper <daniel.kiper@...cle.com>,
        Igor Mammedov <imammedo@...hat.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 08/13] mm, compaction: skip over holes in
 __reset_isolation_suitable

On Fri 21-04-17 14:05:11, Michal Hocko wrote:
> From: Michal Hocko <mhocko@...e.com>
> 
> __reset_isolation_suitable walks the whole zone pfn range and it tries
> to jump over holes by checking the zone for each page. It might still
> stumble over offline pages, though. Skip those by checking PageReserved.

ups, forgot to update the changelog here. s@...eReserved@..._to_online_page()@
 
> Signed-off-by: Michal Hocko <mhocko@...e.com>
> ---
>  mm/compaction.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/mm/compaction.c b/mm/compaction.c
> index 613c59e928cb..fb548e4c7bd4 100644
> --- a/mm/compaction.c
> +++ b/mm/compaction.c
> @@ -236,10 +236,9 @@ static void __reset_isolation_suitable(struct zone *zone)
>  
>  		cond_resched();
>  
> -		if (!pfn_valid(pfn))
> +		page = pfn_to_online_page(pfn);
> +		if (!page)
>  			continue;
> -
> -		page = pfn_to_page(pfn);
>  		if (zone != page_zone(page))
>  			continue;
>  
> -- 
> 2.11.0
> 

-- 
Michal Hocko
SUSE Labs