linux-kernel - Re: Re : .... get_page_from_freelist : MInority Suggestion to accept GFP

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] [day] [month] [year] [list]

Message-ID: <alpine.DEB.2.00.0907030155250.13657@chino.kir.corp.google.com>
Date:	Fri, 3 Jul 2009 02:01:00 -0700 (PDT)
From:	David Rientjes <rientjes@...gle.com>
To:	Mitchell Erblich <erblichs@...thlink.net>
cc:	linux-kernel@...r.kernel.org
Subject: Re: Re : .... get_page_from_freelist : MInority Suggestion to accept
 GFP_NOFAIL accept during boot

On Thu, 2 Jul 2009, Mitchell Erblich wrote:

> Group,
> 
> 
> 	If I may suggest a minority opinion about the depreciating of the
> GFP_NOFAIL flag..
> 
> 	I saw no discussion on the acceptance of using this flag during boot
> and shortly
> 	after boot.
> 
> 	Many kernel structures require memory and thus should guarantee memory
> 	before they continue.
> 	
> 	As Linux is moved within embedded environments with smaller amounts of
> 	physical memory, the chance that earlier mem failures becomes higher.
> 
> 	For this logic alone, my minority opinion is to not depreciate the
> GFP_NOFAIL flag.
> 

I'm confused by your request because all allocations with orders under 
PAGE_ALLOC_COSTLY_ORDER are inherently __GFP_NOFAIL and those that are not 
can easily implement the same behavior in the caller:

	struct page *page;
	do {
		page = alloc_pages(...);
	} while (!page);

Hopefully something could be done to ensure the next call to alloc_pages() 
would be more likely to succeed, but __GFP_NOFAIL doesn't provide that 
anyway.
--
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/