libxl: In libxl_set_vcpuonline check for maximum number of VCPUs against the cpumap.

There is no sense in trying to online (or offline) CPUs when the size of
cpumap is greater than the maximum number of VCPUs the guest can go to.

As such fail the operation if the count of CPUs to online is greater
than what the guest started with. For the offline case we do not
check (as the bits are unset in the cpumap) and let it go through.

We coalesce some of the underlying libxl_set_vcpuonline code
together which was duplicated in QMP and XenStore codepaths.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
(cherry picked from commit d83bf9d224eeb5b73b93c2703f7dba4473cfa89c)
Conflicts:
	tools/libxl/libxl.c
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 0d8cbcad03764e42ff2f0d224aff883c3734d782)
Conflicts:
	tools/libxl/libxl.c
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit ca0f468192d12d8d30c2a48a37c5d3460a464a29)
Conflicts:
	tools/libxl/libxl.c
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
(cherry picked from commit 116bbc6062cd90b98f746c3a058f4ec24347527d)
Conflicts:
	tools/libxl/libxl.c
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index 99cfc6edef8e5c53430910dbfb49408dbd8e0dbb..b0f7e8b8ea884e9181bf966c1e4bd38666a144b1 100644 (file)
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -3963,12 +3963,22 @@ int libxl_set_vcpuonline(libxl_ctx *ctx, uint32_t domid, libxl_bitmap *cpumap)
     libxl_dominfo info;
     char *dompath;
     xs_transaction_t t;
-    int i, rc = ERROR_FAIL;
+    int i, maxcpus, rc = ERROR_FAIL;
 
     if (libxl_domain_info(ctx, &info, domid) < 0) {
         LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "getting domain info list");
         goto out;
     }
+
+    maxcpus = libxl_bitmap_count_set(cpumap);
+    if (maxcpus > info.vcpu_max_id + 1)
+    {
+        LOGE(ERROR, "Requested %d VCPUs, however maxcpus is %d!",
+             maxcpus, info.vcpu_max_id + 1);
+        rc = ERROR_FAIL;
+        goto out;
+    }
+
     if (!(dompath = libxl__xs_get_dompath(gc, domid)))
         goto out;