From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: xen kernel: build failure
Date: Tue, 25 Oct 2011 13:35:27 +0100
Message-ID: <CACC6B9F.23926%keir.xen@gmail.com>
References: <4EA698C8.8030603@amd.com>
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To: Christoph Egger <Christoph.Egger@amd.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 25/10/2011 12:08, "Christoph Egger" <Christoph.Egger@amd.com> wrote:

> 
> Hi,
> 
> Compiling the xen kernel fails with:
> 
> xen/arch/x86/domain.c: In function 'alloc_domain_struct'
> xen/arch/x86/domain.c:191: error: negative width in bit-field '<anonymous>'

Problem is that struct domain has grown bigger than a page for some reason,
in your build environment.

I can't reproduce this.

> Removing the line
> 
> BUILD_BUG_ON(sizeof(*d) > PAGE_SIZE);
> 
> makes xen kernel compile again.

But not actually work properly. We only allocate a single page for the
domain struct. If the struct is bigger than a page, you'll get memory
corruption at run time.

 -- Keir

> 
> Christoph
>