KVM: Support mixed endian machines

Currently kvmtrace is not portable. This will prevent from copying a
trace file from big-endian target to little-endian workstation for analysis.
In the patch, kernel outputs metadata containing a magic number to trace
log, and changes 64-bit words to be u64 instead of a pair of u32s.

Signed-off-by: Tan Li <li.tan@intel.com>
Acked-by: Jerone Young <jyoung5@us.ibm.com>
Acked-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 1c908ac29c6c..0ea064cbfbc8 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -318,14 +318,14 @@ struct kvm_trace_rec {
         __u32 vcpu_id;
         union {
                 struct {
-                        __u32 cycle_lo, cycle_hi;
+                        __u64 cycle_u64;
                         __u32 extra_u32[KVM_TRC_EXTRA_MAX];
                 } cycle;
                 struct {
                         __u32 extra_u32[KVM_TRC_EXTRA_MAX];
                 } nocycle;
         } u;
-};
+} __attribute__((packed));
 
 #define KVMIO 0xAE