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From: Andreas Schwab <schwab@linux-m68k.org>
To: Jiri Kosina <jkosina@suse.cz>
Subject: Re: [PATCH] powerpc: fix personality handling in ppc64_personality()
References: <alpine.LNX.2.00.1208012201520.14910@pobox.suse.cz>
Date: Thu, 02 Aug 2012 00:19:27 +0200
In-Reply-To: <alpine.LNX.2.00.1208012201520.14910@pobox.suse.cz> (Jiri
 Kosina's message of "Wed, 1 Aug 2012 22:03:42 +0200 (CEST)")
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Cc: Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org
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Jiri Kosina <jkosina@suse.cz> writes:

>  	if (personality(current->personality) == PER_LINUX32
> -	    && personality == PER_LINUX)
> -		personality = PER_LINUX32;
> +	    && personality(personality) == PER_LINUX)
> +		personality &= ~PER_LINUX | PER_LINUX32;

That doesn't work.  ~PER_LINUX is -1, so this is a no-op.

>  	ret = sys_personality(personality);
> -	if (ret == PER_LINUX32)
> -		ret = PER_LINUX;
> +	if (personality(ret) == PER_LINUX32)
> +		ret &= ~PER_LINUX32 | PER_LINUX;

That only "works" because PER_LINUX is 0.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."