linux-kernel - Re: [PATCH] cpumask: alloc blank cpumask left over

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:	Sat, 06 Jun 2009 12:39:53 +0300
From:	Avi Kivity <avi@...hat.com>
To:	Yinghai Lu <yinghai@...nel.org>
CC:	Rusty Russell <rusty@...tcorp.com.au>, Ingo Molnar <mingo@...e.hu>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] cpumask: alloc blank cpumask left over

Yinghai Lu wrote:

  

>> Using __GFP_ZERO is equivalent to using memset() instead of
>> cpumask_clear().  It's better to call cpumask_clear() or provide an API
>> to alloc+clear.
>>
>> Further, what about the non-MAXSMP case:
>>
>>
>>    static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
>>    {
>>            return true;
>>    }
>>
>>
>> We explicity clear on MAXSMP and rely on static initialization for the
>> non-MAXSMP, laying a neat trap for anyone who makes the variable
>> non-static.  Let's be less subtle that that.
>>     
>
> or have zalloc_cpumask_var() ?
>   

That's the best choice IMO.

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.

--
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/