2 files changed, 30 insertions(+), 11 deletions(-)
include/linux/kvm.h  |   17 ++++++++++++++---
virt/kvm/kvm_trace.c |   24 ++++++++++++++++--------


 *Updates:
        Create global definitions for setting trace records as opposed to
        explicitly setting them inside of a function.

This patch fixes kvmtrace use on big endian systems. When using bit fields the 
compiler will lay data out in the wrong order expected when laid down into a 
file. This fixes it by using one variable instead of using bit fields.

Signed-off-by: Jerone Young <[EMAIL PROTECTED]>

diff --git a/include/linux/kvm.h b/include/linux/kvm.h
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -311,9 +311,13 @@ struct kvm_s390_interrupt {
 
 /* This structure represents a single trace buffer record. */
 struct kvm_trace_rec {
-       __u32 event:28;
-       __u32 extra_u32:3;
-       __u32 cycle_in:1;
+       /* variable rec_val
+        * is split into:
+        * bits 0 - 27  -> event id
+        * bits 28 -30  -> number of extra data args of size u32
+        * bits 31      -> binary indicator for if tsc is in record
+        */
+       __u32 rec_val;
        __u32 pid;
        __u32 vcpu_id;
        union {
@@ -326,6 +330,13 @@ struct kvm_trace_rec {
                } nocycle;
        } u;
 } __attribute__((packed));
+
+#define TRACE_REC_EVENT_ID (val) \
+               (0x0fffffff & (val))
+#define TRACE_REC_NUM_DATA_ARGS (val) \
+               (0x70000000 & (val << 28))
+#define TRACE_REC_TCS (val) \
+               (0x80000000 & (val << 31))
 
 #define KVMIO 0xAE
 
diff --git a/virt/kvm/kvm_trace.c b/virt/kvm/kvm_trace.c
--- a/virt/kvm/kvm_trace.c
+++ b/virt/kvm/kvm_trace.c
@@ -54,12 +54,17 @@ static void kvm_add_trace(void *probe_pr
        struct kvm_trace *kt = kvm_trace;
        struct kvm_trace_rec rec;
        struct kvm_vcpu *vcpu;
-       int    i, extra, size;
+       int    i, size;
+       u32 extra;
 
        if (unlikely(kt->trace_state != KVM_TRACE_STATE_RUNNING))
                return;
 
-       rec.event       = va_arg(*args, u32);
+       rec.rec_val = 0;
+       
+       /* set event id */      
+       rec.rec_val     |= TRACE_REC_EVENT_ID(va_arg(*args, u32));
+
        vcpu            = va_arg(*args, struct kvm_vcpu *);
        rec.pid         = current->tgid;
        rec.vcpu_id     = vcpu->vcpu_id;
@@ -67,21 +72,24 @@ static void kvm_add_trace(void *probe_pr
        extra           = va_arg(*args, u32);
        WARN_ON(!(extra <= KVM_TRC_EXTRA_MAX));
        extra           = min_t(u32, extra, KVM_TRC_EXTRA_MAX);
-       rec.extra_u32   = extra;
 
-       rec.cycle_in    = p->cycle_in;
+       /* set inidicator for tcs record */
+       rec.rec_val     |= TRACE_REC_TCS(p->cycle_in);
 
-       if (rec.cycle_in) {
+       /* set extra data num */
+       rec.rec_val     |= TRACE_REC_NUM_DATA_ARGS(extra);
+
+       if (p->cycle_in) {
                rec.u.cycle.cycle_u64 = get_cycles();
 
-               for (i = 0; i < rec.extra_u32; i++)
+               for (i = 0; i < extra; i++)
                        rec.u.cycle.extra_u32[i] = va_arg(*args, u32);
        } else {
-               for (i = 0; i < rec.extra_u32; i++)
+               for (i = 0; i < extra; i++)
                        rec.u.nocycle.extra_u32[i] = va_arg(*args, u32);
        }
 
-       size = calc_rec_size(rec.cycle_in, rec.extra_u32 * sizeof(u32));
+       size = calc_rec_size(p->cycle_in, extra * sizeof(u32));
        relay_write(kt->rchan, &rec, size);
 }
 
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