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From: David Miller <davem@davemloft.net>
To: tj@kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: More problems in setup_pcpu_remap()
Date: Wed, 01 Apr 2009 21:31:12 -0700 (PDT)	[thread overview]
Message-ID: <20090401.213112.96144152.davem@davemloft.net> (raw)


The way this code is currently designed, it can exhaust all of the
VMALLOC address space on both x86 and x86_64, and then some.

It allocates PMD_SIZE * num_possible_cpus() of vmalloc space.

PMD_SIZE is 2MB, num_possible_cpus() can be up to 4096....
which can easily exceed (VMALLOC_END - VMALLOC_START)

Initially I had set out to implement sparc64 support for the new
per-cpu stuff, but it looks like I'm stuck finding bugs in the x86
implementation instead :-)

             reply	other threads:[~2009-04-02  4:31 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-02  4:31 David Miller [this message]
2009-04-02  4:42 ` More problems in setup_pcpu_remap() Tejun Heo
2009-04-02  4:52   ` David Miller
2009-04-02  5:55     ` Tejun Heo
2009-04-02  7:07       ` David Miller
2009-04-02  7:22         ` Tejun Heo

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