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From: Rusty Russell <rusty@rustcorp.com.au>
To: Arnd Bergmann <arnd@arndb.de>
Subject: Re: cpumask: fix compat getaffinity
Date: Sat, 8 May 2010 18:00:47 +0930
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       Andi Kleen <andi@firstfloor.org>, Ken Werner <ken.werner@web.de>
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On Fri, 7 May 2010 10:15:49 pm Arnd Bergmann wrote:
> Commit a45185d2d "cpumask: convert kernel/compat.c" broke
> libnuma, which abuses sched_getaffinity to find out NR_CPUS
> in order to parse /sys/devices/system/node/node*/cpumap.
> 
> On NUMA systems with less than 32 possibly CPUs, the
> current compat_sys_sched_getaffinity now returns '4'
> instead of the actual NR_CPUS/8, which makes libnuma
> bail out when parsing the cpumap.

Really?  AFAICT the cpumap is printed using nr_cpu_ids too.  Can you
give an example of what cpumap is on this system?

Confused,
Rusty.