libxc: fix tracing (broken with hypercall buffers)

the attached patch makes Xen tracing work again, after the introduction
of the hypercall buffers broke it. Just a missing line.

Thanks to Uwe Dannowski for reporting this.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/libxc/xc_tbuf.c b/tools/libxc/xc_tbuf.c
index 5f91b6eeef8670e5d2a569e243b0d1a71340aada..b52fa8fa876aa7a296443e2d56827bbd56ee4be8 100644 (file)
--- a/tools/libxc/xc_tbuf.c
+++ b/tools/libxc/xc_tbuf.c
@@ -121,6 +121,7 @@ int xc_tbuf_set_cpu_mask(xc_interface *xch, uint32_t mask)
     uint64_t mask64 = mask;
 
     bytemap = xc_hypercall_buffer_alloc(xch, bytemap, sizeof(mask64));
+    if (bytemap == NULL)
     {
         PERROR("Could not allocate memory for xc_tbuf_set_cpu_mask hypercall");
         goto out;