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Alejandro Vallejo
6efc654a0b
The procedure used to customize the domain CPU policy is broken when toolstack tries to set leaves (with subleaves) that the hypervisor didn't need to serialise (i.e: because they where empty subleaves). During typical domain creation xg does the following: 1. Probe Xen for max #leaves that a policy may have 2. Allocate memory for that many leaves 3. Tell the hypervisor to dump the policy in the allocated buffer 4. Deserialise it 5. Modify it 6. Reserialise it 7. Send it back to Xen The problem is that (3) overrides nr_leaves, which then makes (6) fail in the case where (5) has added subleaves that Xen understands but didn't need to serialize on (3). The fix uses an opaque CPU policy object so we can (a) avoid probing Xen for sizes, and (b) trivially have knowledge of the actual size of the buffer. While at it, fix xc_cpu_policy_destroy() to preserve errno accross free() Signed-off-by: Alejandro Vallejo <alejandro.vallejo@cloud.com> Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>