linux-kernel - Re: [PATCH] mm: Use GFP_KERNEL allocation for the page cache in page_cache

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]

Date:	Wed, 18 Mar 2015 15:37:33 +0100
From:	Michal Hocko <mhocko@...e.cz>
To:	Rik van Riel <riel@...hat.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Al Viro <viro@...iv.linux.org.uk>,
	Johannes Weiner <hannes@...xchg.org>,
	Mel Gorman <mgorman@...e.de>, Neil Brown <neilb@...e.de>,
	Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>,
	Sage Weil <sage@...tank.com>, Mark Fasheh <mfasheh@...e.com>,
	linux-mm@...ck.org, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] mm: Use GFP_KERNEL allocation for the page cache in
 page_cache_read

On Wed 18-03-15 10:32:57, Rik van Riel wrote:
> On 03/18/2015 10:09 AM, Michal Hocko wrote:
> 
> > diff --git a/mm/filemap.c b/mm/filemap.c
> > index 968cd8e03d2e..26f62ba79f50 100644
> > --- a/mm/filemap.c
> > +++ b/mm/filemap.c
> > @@ -1752,7 +1752,7 @@ static int page_cache_read(struct file *file, pgoff_t offset)
> >  	int ret;
> >  
> >  	do {
> > -		page = page_cache_alloc_cold(mapping);
> > +		page = __page_cache_alloc(GFP_KERNEL|__GFP_COLD);
> >  		if (!page)
> >  			return -ENOMEM;
> 
> Won't this break on highmem systems, by failing to
> allocate the page cache from highmem, where previously
> it would?

It will! This is broken. I can see inode_init_always now. We need to add
GFP_HIGHUSER_MOVABLE here.

Thanks for pointing this out!

-- 
Michal Hocko
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/