diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
index 5a2a9a6b83..4baecc2447 100644
--- a/xen/arch/arm/domain.c
+++ b/xen/arch/arm/domain.c
@@ -21,6 +21,7 @@
 #include <xen/wait.h>
 
 #include <asm/alternative.h>
+#include <asm/cpuerrata.h>
 #include <asm/cpufeature.h>
 #include <asm/current.h>
 #include <asm/event.h>
@@ -572,6 +573,13 @@ int vcpu_initialise(struct vcpu *v)
     if ( (rc = vcpu_vtimer_init(v)) != 0 )
         goto fail;
 
+    /*
+     * The workaround 2 (i.e SSBD mitigation) is enabled by default if
+     * supported.
+     */
+    if ( get_ssbd_state() == ARM_SSBD_RUNTIME )
+        v->arch.cpu_info->flags |= CPUINFO_WORKAROUND_2_FLAG;
+
     return rc;
 
 fail:
diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index d71adfa745..e47ec8aad5 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -2021,10 +2021,23 @@ inject_abt:
         inject_iabt_exception(regs, gva, hsr.len);
 }
 
+static inline bool needs_ssbd_flip(struct vcpu *v)
+{
+    if ( !check_workaround_ssbd() )
+        return false;
+
+    return !(v->arch.cpu_info->flags & CPUINFO_WORKAROUND_2_FLAG) &&
+             cpu_require_ssbd_mitigation();
+}
+
 static void enter_hypervisor_head(struct cpu_user_regs *regs)
 {
     if ( guest_mode(regs) )
     {
+        /* If the guest has disabled the workaround, bring it back on. */
+        if ( needs_ssbd_flip(current) )
+            arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2_FID, 1, NULL);
+
         /*
          * If we pended a virtual abort, preserve it until it gets cleared.
          * See ARM ARM DDI 0487A.j D1.14.3 (Virtual Interrupts) for details,
@@ -2270,6 +2283,13 @@ void leave_hypervisor_tail(void)
              */
             SYNCHRONIZE_SERROR(SKIP_SYNCHRONIZE_SERROR_ENTRY_EXIT);
 
+            /*
+             * The hypervisor runs with the workaround always present.
+             * If the guest wants it disabled, so be it...
+             */
+            if ( needs_ssbd_flip(current) )
+                arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2_FID, 0, NULL);
+
             return;
         }
         local_irq_enable();
diff --git a/xen/arch/arm/vsmc.c b/xen/arch/arm/vsmc.c
index 40a80d5760..c4ccae6030 100644
--- a/xen/arch/arm/vsmc.c
+++ b/xen/arch/arm/vsmc.c
@@ -18,6 +18,7 @@
 #include <xen/lib.h>
 #include <xen/types.h>
 #include <public/arch-arm/smccc.h>
+#include <asm/cpuerrata.h>
 #include <asm/cpufeature.h>
 #include <asm/monitor.h>
 #include <asm/regs.h>
@@ -104,6 +105,23 @@ static bool handle_arch(struct cpu_user_regs *regs)
             if ( cpus_have_cap(ARM_HARDEN_BRANCH_PREDICTOR) )
                 ret = 0;
             break;
+        case ARM_SMCCC_ARCH_WORKAROUND_2_FID:
+            switch ( get_ssbd_state() )
+            {
+            case ARM_SSBD_UNKNOWN:
+            case ARM_SSBD_FORCE_DISABLE:
+                break;
+
+            case ARM_SSBD_RUNTIME:
+                ret = ARM_SMCCC_SUCCESS;
+                break;
+
+            case ARM_SSBD_FORCE_ENABLE:
+            case ARM_SSBD_MITIGATED:
+                ret = ARM_SMCCC_NOT_REQUIRED;
+                break;
+            }
+            break;
         }
 
         set_user_reg(regs, 0, ret);
@@ -114,6 +132,25 @@ static bool handle_arch(struct cpu_user_regs *regs)
     case ARM_SMCCC_ARCH_WORKAROUND_1_FID:
         /* No return value */
         return true;
+
+    case ARM_SMCCC_ARCH_WORKAROUND_2_FID:
+    {
+        bool enable = (uint32_t)get_user_reg(regs, 1);
+
+        /*
+         * ARM_WORKAROUND_2_FID should only be called when mitigation
+         * state can be changed at runtime.
+         */
+        if ( unlikely(get_ssbd_state() != ARM_SSBD_RUNTIME) )
+            return true;
+
+        if ( enable )
+            get_cpu_info()->flags |= CPUINFO_WORKAROUND_2_FLAG;
+        else
+            get_cpu_info()->flags &= ~CPUINFO_WORKAROUND_2_FLAG;
+
+        return true;
+    }
     }
 
     return false;
diff --git a/xen/include/asm-arm/current.h b/xen/include/asm-arm/current.h
index 7a0971fdea..f9819b34fc 100644
--- a/xen/include/asm-arm/current.h
+++ b/xen/include/asm-arm/current.h
@@ -7,6 +7,10 @@
 #include <asm/percpu.h>
 #include <asm/processor.h>
 
+/* Tell whether the guest vCPU enabled Workaround 2 (i.e variant 4) */
+#define CPUINFO_WORKAROUND_2_FLAG_SHIFT   0
+#define CPUINFO_WORKAROUND_2_FLAG (_AC(1, U) << CPUINFO_WORKAROUND_2_FLAG_SHIFT)
+
 #ifndef __ASSEMBLY__
 
 struct vcpu;
@@ -21,7 +25,7 @@ DECLARE_PER_CPU(struct vcpu *, curr_vcpu);
 struct cpu_info {
     struct cpu_user_regs guest_cpu_user_regs;
     unsigned long elr;
-    unsigned int pad;
+    uint32_t flags;
 };
 
 static inline struct cpu_info *get_cpu_info(void)