spd: trusty: only process one function ID at a time
In multi-guest trusty environment, all guest's SMCs will be
forwarded to Trusty. This change only allows 1 guest's SMC
to be forwarded at a time and returns 'busy' status to all
other requests.
Change-Id: I2144467d11e3680e28ec816adeec2766bca114d4
Signed-off-by: Anthony Zhou <anzhou@nvidia.com>
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/services/spd/trusty/trusty.c b/services/spd/trusty/trusty.c
index 2af568e..cb28b2e 100644
--- a/services/spd/trusty/trusty.c
+++ b/services/spd/trusty/trusty.c
@@ -80,6 +80,8 @@
struct args trusty_init_context_stack(void **sp, void *new_stack);
struct args trusty_context_switch_helper(void **sp, void *smc_params);
+static uint32_t current_vmid;
+
static struct trusty_cpu_ctx *get_trusty_ctx(void)
{
return &trusty_cpu_ctx[plat_my_core_pos()];
@@ -231,6 +233,7 @@
uint64_t flags)
{
struct args ret;
+ uint32_t vmid = 0;
if (is_caller_secure(flags)) {
if (smc_fid == SMC_SC_NS_RETURN) {
@@ -252,8 +255,21 @@
case SMC_FC_FIQ_EXIT:
return trusty_fiq_exit(handle, x1, x2, x3);
default:
+ if (is_hypervisor_mode())
+ vmid = SMC_GET_GP(handle, CTX_GPREG_X7);
+
+ if ((current_vmid != 0) && (current_vmid != vmid)) {
+ /* This message will cause SMC mechanism
+ * abnormal in multi-guest environment.
+ * Change it to WARN in case you need it.
+ */
+ VERBOSE("Previous SMC not finished.\n");
+ SMC_RET1(handle, SM_ERR_BUSY);
+ }
+ current_vmid = vmid;
ret = trusty_context_switch(NON_SECURE, smc_fid, x1,
x2, x3);
+ current_vmid = 0;
SMC_RET1(handle, ret.r0);
}
}
