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Message-ID: <3F579767.8030806@colorfullife.com>
Date: Thu, 04 Sep 2003 21:49:59 +0200
From: Manfred Spraul <manfred@colorfullife.com>
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To: "Henry Qian" <henry@amperion.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: SLAB_LEVEL_MASK question
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Hi Henry,

>The kernel panics because in the flags variable, I have other flags
>(0x1f0) besides SLAB_ATOMIC.
>  
>
Which flags were set? __GFP_WAIT must not be set [i.e. will panic], the 
other combinations are invalid. The only legal values for the flags 
variable are 0 or SLAB_ATOMIC [aka GFP_ATOMIC, aka __GFP_HIGH].

>I modified it to:
>
>        if (in_interrupt() && (flags & SLAB_ATOMIC) != SLAB_ATOMIC)
>                BUG();
>
>It seems working fine.
>
>Is this good?
>  
>
No, it's wrong. Your driver will panic once in a while, especially under 
memory intensive stress tests.

--
    Manfred