Re: [Libvir] [PATCH] Guard a negative value of "virsh setmem" and "virsh setmexmem"
On Fri, Mar 16, 2007 at 12:26:18PM +0900, Masayuki Sunou wrote:
Hi
"virsh setmem" and "virsh setmexmem" have the problem of setting a
very
big value in the domain when -1 is set in the domain.
As a result, I detected the problem of doing abnormal operation of Xen
in 64bit machine. (virsh setmem)
Therefore, I contribute the patch that corrects the argument of the
function to guard a negative value.
[...]
unsigned long virDomainGetMaxMemory (virDomainPtr domain);
int virDomainSetMaxMemory (virDomainPtr domain,
- unsigned long memory);
+ int memory);
int virDomainSetMemory (virDomainPtr domain,
- unsigned long memory);
+ int memory);
int virDomainGetMaxVcpus (virDomainPtr domain);
Sorry you really cannot do that:
- it breaks the API (by changing a public interface)
- it breaks the ABI (by changing the parameter size on 64bit boxes)
- and it makes Set and Get routines inconsistent.
This kind of errors must be caught when calling the API, if one casts
from a signed to the unsigned long a check must be done at that point
for negative value by the caller. I'm unsure in what environment you
got the problem, but that's not the right way to fix it :-)
Daniel
--
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Daniel Veillard | virtualization library http://libvirt.org/
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