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Re: [Xen-devel] [PATCH]Check the values of MAX_VIRT_CPUS and NR_CPUS for

To: Atsushi SAKAI <sakaia@xxxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [PATCH]Check the values of MAX_VIRT_CPUS and NR_CPUS for SMP
From: Keir Fraser <Keir.Fraser@xxxxxxxxxxxx>
Date: Fri, 21 Apr 2006 07:41:15 +0100
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On 21 Apr 2006, at 02:31, Atsushi SAKAI wrote:

But the logical limit of the IA64 Max CPU is larger than 64.
If someone change these values, some possibility make this error again.

To avoid this problem, I believe this check code should be exists.

See how we solve this on x86 near the top of do_boot_cpu() in arch/x86/smpboot.c. Essentially we allocate extra idle domains on demand to give us enough idle vcpus for one per physical cpu.

 -- Keir

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