@@ -1800,7 +1800,7 @@ int xc_cpuid_set(xc_interface *xch,
char **config_transformed);
int xc_cpuid_apply_policy(xc_interface *xch,
uint32_t domid,
- uint32_t *featureset,
+ const uint32_t *featureset,
unsigned int nr_features);
int xc_mca_op(xc_interface *xch, struct xen_mc *mc);
int xc_mca_op_inject_v2(xc_interface *xch, unsigned int flags,
@@ -1,5 +1,5 @@
/******************************************************************************
- * xc_cpuid_x86.c
+ * xc_cpuid_x86.c
*
* Compute cpuid of a domain.
*
@@ -329,7 +329,7 @@ static void cpuid(const unsigned int *input, unsigned int *regs)
static int get_cpuid_domain_info(xc_interface *xch, uint32_t domid,
struct cpuid_domain_info *info,
- uint32_t *featureset,
+ const uint32_t *featureset,
unsigned int nr_features)
{
struct xen_domctl domctl = {};
@@ -804,8 +804,7 @@ static void sanitise_featureset(struct cpuid_domain_info *info)
}
int xc_cpuid_apply_policy(xc_interface *xch, uint32_t domid,
- uint32_t *featureset,
- unsigned int nr_features)
+ const uint32_t *featureset, unsigned int nr_features)
{
struct cpuid_domain_info info = {};
unsigned int input[2] = { 0, 0 }, regs[4];
@@ -895,7 +894,7 @@ int xc_cpuid_apply_policy(xc_interface *xch, uint32_t domid,
* 'k' -> pass through host value
* 's' -> pass through the first time and then keep the same value
* across save/restore and migration.
- *
+ *
* For 's' and 'x' the configuration is overwritten with the value applied.
*/
int xc_cpuid_set(
@@ -906,7 +905,8 @@ int xc_cpuid_set(
unsigned int i, j, regs[4], polregs[4];
struct cpuid_domain_info info = {};
- memset(config_transformed, 0, 4 * sizeof(*config_transformed));
+ for ( i = 0; i < 4; ++i )
+ config_transformed[i] = NULL;
rc = get_cpuid_domain_info(xch, domid, &info, NULL, 0);
if ( rc )
@@ -924,7 +924,7 @@ int xc_cpuid_set(
regs[i] = polregs[i];
continue;
}
-
+
config_transformed[i] = calloc(33, 1); /* 32 bits, NUL terminator. */
if ( config_transformed[i] == NULL )
{
@@ -932,6 +932,13 @@ int xc_cpuid_set(
goto fail;
}
+ /*
+ * Notes for following this algorithm:
+ *
+ * While it will accept any leaf data, it only makes sense to use on
+ * feature leaves. regs[] initially contains the host values. This,
+ * with the fall-through chain is how the 's' and 'k' options works.
+ */
for ( j = 0; j < 32; j++ )
{
unsigned char val = !!((regs[i] & (1U << (31 - j))));