Re: [libvirt] [PATCH] Allow 32-on-64 execution for LXC guests
On 02/23/2011 10:20 AM, Daniel P. Berrange wrote:
Using the 'personality(2)' system call, we can make a
container
on an x86_64 host appear to be i686. Likewise for most other
Linux 64bit arches.
* src/lxc/lxc_conf.c: Fill in 32bit capabilities for x86_64 hosts
* src/lxc/lxc_container.h, src/lxc/lxc_container.c: Add API to
check if an arch has a 32bit alternative
* src/lxc/lxc_controller.c: Set the process personality when
starting guest
@@ -73,7 +75,7 @@ virCapsPtr lxcCapsInit(void)
if ((guest = virCapabilitiesAddGuest(caps,
"exe",
utsname.machine,
- sizeof(int) == 4 ? 32 : 8,
+ sizeof(void*) == 4 ? 32 : 64,
How long have we had that bug? Thankfully, sizeof(int) is 4 on both
32-bit and 64-bit Linux, so we were never setting 8 as the number of
bits per CPU word. This fix alone is worth the patch.
ACK.
--
Eric Blake eblake(a)redhat.com +1-801-349-2682
Libvirt virtualization library http://libvirt.org
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