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-rw-r--r--arch/arm/kvm/arm.c67
-rw-r--r--arch/arm/kvm/coproc.c24
-rw-r--r--arch/arm/kvm/coproc.h18
-rw-r--r--arch/arm/kvm/handle_exit.c8
-rw-r--r--arch/arm/kvm/hyp/hyp-entry.S28
-rw-r--r--arch/arm/kvm/init.S51
-rw-r--r--arch/arm/kvm/interrupts.S4
-rw-r--r--arch/arm/kvm/mmu.c59
-rw-r--r--arch/arm/kvm/psci.c8
9 files changed, 173 insertions, 94 deletions
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index e3c8105ada65..8a31906bdc9b 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -53,7 +53,6 @@ __asm__(".arch_extension virt");
static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page);
static kvm_cpu_context_t __percpu *kvm_host_cpu_state;
-static unsigned long hyp_default_vectors;
/* Per-CPU variable containing the currently running vcpu. */
static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu);
@@ -227,6 +226,13 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
else
r = kvm->arch.vgic.msis_require_devid;
break;
+ case KVM_CAP_ARM_USER_IRQ:
+ /*
+ * 1: EL1_VTIMER, EL1_PTIMER, and PMU.
+ * (bump this number if adding more devices)
+ */
+ r = 1;
+ break;
default:
r = kvm_arch_dev_ioctl_check_extension(kvm, ext);
break;
@@ -348,15 +354,14 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
vcpu->arch.host_cpu_context = this_cpu_ptr(kvm_host_cpu_state);
kvm_arm_set_running_vcpu(vcpu);
+
+ kvm_vgic_load(vcpu);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
- /*
- * The arch-generic KVM code expects the cpu field of a vcpu to be -1
- * if the vcpu is no longer assigned to a cpu. This is used for the
- * optimized make_all_cpus_request path.
- */
+ kvm_vgic_put(vcpu);
+
vcpu->cpu = -1;
kvm_arm_set_running_vcpu(NULL);
@@ -514,13 +519,7 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu)
return ret;
}
- /*
- * Enable the arch timers only if we have an in-kernel VGIC
- * and it has been properly initialized, since we cannot handle
- * interrupts from the virtual timer with a userspace gic.
- */
- if (irqchip_in_kernel(kvm) && vgic_initialized(kvm))
- ret = kvm_timer_enable(vcpu);
+ ret = kvm_timer_enable(vcpu);
return ret;
}
@@ -630,16 +629,23 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
* non-preemptible context.
*/
preempt_disable();
+
kvm_pmu_flush_hwstate(vcpu);
+
kvm_timer_flush_hwstate(vcpu);
kvm_vgic_flush_hwstate(vcpu);
local_irq_disable();
/*
- * Re-check atomic conditions
+ * If we have a singal pending, or need to notify a userspace
+ * irqchip about timer or PMU level changes, then we exit (and
+ * update the timer level state in kvm_timer_update_run
+ * below).
*/
- if (signal_pending(current)) {
+ if (signal_pending(current) ||
+ kvm_timer_should_notify_user(vcpu) ||
+ kvm_pmu_should_notify_user(vcpu)) {
ret = -EINTR;
run->exit_reason = KVM_EXIT_INTR;
}
@@ -711,6 +717,12 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = handle_exit(vcpu, run, ret);
}
+ /* Tell userspace about in-kernel device output levels */
+ if (unlikely(!irqchip_in_kernel(vcpu->kvm))) {
+ kvm_timer_update_run(vcpu);
+ kvm_pmu_update_run(vcpu);
+ }
+
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
return ret;
@@ -1109,8 +1121,16 @@ static void cpu_init_hyp_mode(void *dummy)
kvm_arm_init_debug();
}
+static void cpu_hyp_reset(void)
+{
+ if (!is_kernel_in_hyp_mode())
+ __hyp_reset_vectors();
+}
+
static void cpu_hyp_reinit(void)
{
+ cpu_hyp_reset();
+
if (is_kernel_in_hyp_mode()) {
/*
* __cpu_init_stage2() is safe to call even if the PM
@@ -1118,16 +1138,11 @@ static void cpu_hyp_reinit(void)
*/
__cpu_init_stage2();
} else {
- if (__hyp_get_vectors() == hyp_default_vectors)
- cpu_init_hyp_mode(NULL);
+ cpu_init_hyp_mode(NULL);
}
-}
-static void cpu_hyp_reset(void)
-{
- if (!is_kernel_in_hyp_mode())
- __cpu_reset_hyp_mode(hyp_default_vectors,
- kvm_get_idmap_start());
+ if (vgic_present)
+ kvm_vgic_init_cpu_hardware();
}
static void _kvm_arch_hardware_enable(void *discard)
@@ -1313,12 +1328,6 @@ static int init_hyp_mode(void)
goto out_err;
/*
- * It is probably enough to obtain the default on one
- * CPU. It's unlikely to be different on the others.
- */
- hyp_default_vectors = __hyp_get_vectors();
-
- /*
* Allocate stack pages for Hypervisor-mode
*/
for_each_possible_cpu(cpu) {
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
index 3e5e4194ef86..2c14b69511e9 100644
--- a/arch/arm/kvm/coproc.c
+++ b/arch/arm/kvm/coproc.c
@@ -40,6 +40,24 @@
* Co-processor emulation
*****************************************************************************/
+static bool write_to_read_only(struct kvm_vcpu *vcpu,
+ const struct coproc_params *params)
+{
+ WARN_ONCE(1, "CP15 write to read-only register\n");
+ print_cp_instr(params);
+ kvm_inject_undefined(vcpu);
+ return false;
+}
+
+static bool read_from_write_only(struct kvm_vcpu *vcpu,
+ const struct coproc_params *params)
+{
+ WARN_ONCE(1, "CP15 read to write-only register\n");
+ print_cp_instr(params);
+ kvm_inject_undefined(vcpu);
+ return false;
+}
+
/* 3 bits per cache level, as per CLIDR, but non-existent caches always 0 */
static u32 cache_levels;
@@ -502,15 +520,15 @@ static int emulate_cp15(struct kvm_vcpu *vcpu,
if (likely(r->access(vcpu, params, r))) {
/* Skip instruction, since it was emulated */
kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
- return 1;
}
- /* If access function fails, it should complain. */
} else {
+ /* If access function fails, it should complain. */
kvm_err("Unsupported guest CP15 access at: %08lx\n",
*vcpu_pc(vcpu));
print_cp_instr(params);
+ kvm_inject_undefined(vcpu);
}
- kvm_inject_undefined(vcpu);
+
return 1;
}
diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h
index eef1759c2b65..3a41b7d1eb86 100644
--- a/arch/arm/kvm/coproc.h
+++ b/arch/arm/kvm/coproc.h
@@ -81,24 +81,6 @@ static inline bool read_zero(struct kvm_vcpu *vcpu,
return true;
}
-static inline bool write_to_read_only(struct kvm_vcpu *vcpu,
- const struct coproc_params *params)
-{
- kvm_debug("CP15 write to read-only register at: %08lx\n",
- *vcpu_pc(vcpu));
- print_cp_instr(params);
- return false;
-}
-
-static inline bool read_from_write_only(struct kvm_vcpu *vcpu,
- const struct coproc_params *params)
-{
- kvm_debug("CP15 read to write-only register at: %08lx\n",
- *vcpu_pc(vcpu));
- print_cp_instr(params);
- return false;
-}
-
/* Reset functions */
static inline void reset_unknown(struct kvm_vcpu *vcpu,
const struct coproc_reg *r)
diff --git a/arch/arm/kvm/handle_exit.c b/arch/arm/kvm/handle_exit.c
index 96af65a30d78..5fd7968cdae9 100644
--- a/arch/arm/kvm/handle_exit.c
+++ b/arch/arm/kvm/handle_exit.c
@@ -160,6 +160,14 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
case ARM_EXCEPTION_DATA_ABORT:
kvm_inject_vabt(vcpu);
return 1;
+ case ARM_EXCEPTION_HYP_GONE:
+ /*
+ * HYP has been reset to the hyp-stub. This happens
+ * when a guest is pre-empted by kvm_reboot()'s
+ * shutdown call.
+ */
+ run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ return 0;
default:
kvm_pr_unimpl("Unsupported exception type: %d",
exception_index);
diff --git a/arch/arm/kvm/hyp/hyp-entry.S b/arch/arm/kvm/hyp/hyp-entry.S
index 96beb53934c9..95a2faefc070 100644
--- a/arch/arm/kvm/hyp/hyp-entry.S
+++ b/arch/arm/kvm/hyp/hyp-entry.S
@@ -126,11 +126,29 @@ hyp_hvc:
*/
pop {r0, r1, r2}
- /* Check for __hyp_get_vectors */
- cmp r0, #-1
- mrceq p15, 4, r0, c12, c0, 0 @ get HVBAR
- beq 1f
+ /*
+ * Check if we have a kernel function, which is guaranteed to be
+ * bigger than the maximum hyp stub hypercall
+ */
+ cmp r0, #HVC_STUB_HCALL_NR
+ bhs 1f
+ /*
+ * Not a kernel function, treat it as a stub hypercall.
+ * Compute the physical address for __kvm_handle_stub_hvc
+ * (as the code lives in the idmaped page) and branch there.
+ * We hijack ip (r12) as a tmp register.
+ */
+ push {r1}
+ ldr r1, =kimage_voffset
+ ldr r1, [r1]
+ ldr ip, =__kvm_handle_stub_hvc
+ sub ip, ip, r1
+ pop {r1}
+
+ bx ip
+
+1:
push {lr}
mov lr, r0
@@ -142,7 +160,7 @@ THUMB( orr lr, #1)
blx lr @ Call the HYP function
pop {lr}
-1: eret
+ eret
guest_trap:
load_vcpu r0 @ Load VCPU pointer to r0
diff --git a/arch/arm/kvm/init.S b/arch/arm/kvm/init.S
index bf89c919efc1..570ed4a9c261 100644
--- a/arch/arm/kvm/init.S
+++ b/arch/arm/kvm/init.S
@@ -23,6 +23,7 @@
#include <asm/kvm_asm.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
+#include <asm/virt.h>
/********************************************************************
* Hypervisor initialization
@@ -39,6 +40,10 @@
* - Setup the page tables
* - Enable the MMU
* - Profit! (or eret, if you only care about the code).
+ *
+ * Another possibility is to get a HYP stub hypercall.
+ * We discriminate between the two by checking if r0 contains a value
+ * that is less than HVC_STUB_HCALL_NR.
*/
.text
@@ -58,6 +63,10 @@ __kvm_hyp_init:
W(b) .
__do_hyp_init:
+ @ Check for a stub hypercall
+ cmp r0, #HVC_STUB_HCALL_NR
+ blo __kvm_handle_stub_hvc
+
@ Set stack pointer
mov sp, r0
@@ -112,20 +121,46 @@ __do_hyp_init:
eret
- @ r0 : stub vectors address
-ENTRY(__kvm_hyp_reset)
+ENTRY(__kvm_handle_stub_hvc)
+ cmp r0, #HVC_SOFT_RESTART
+ bne 1f
+
+ /* The target is expected in r1 */
+ msr ELR_hyp, r1
+ mrs r0, cpsr
+ bic r0, r0, #MODE_MASK
+ orr r0, r0, #HYP_MODE
+THUMB( orr r0, r0, #PSR_T_BIT )
+ msr spsr_cxsf, r0
+ b reset
+
+1: cmp r0, #HVC_RESET_VECTORS
+ bne 1f
+
+reset:
/* We're now in idmap, disable MMU */
mrc p15, 4, r1, c1, c0, 0 @ HSCTLR
- ldr r2, =(HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I)
- bic r1, r1, r2
+ ldr r0, =(HSCTLR_M | HSCTLR_A | HSCTLR_C | HSCTLR_I)
+ bic r1, r1, r0
mcr p15, 4, r1, c1, c0, 0 @ HSCTLR
- /* Install stub vectors */
- mcr p15, 4, r0, c12, c0, 0 @ HVBAR
- isb
+ /*
+ * Install stub vectors, using ardb's VA->PA trick.
+ */
+0: adr r0, 0b @ PA(0)
+ movw r1, #:lower16:__hyp_stub_vectors - 0b @ VA(stub) - VA(0)
+ movt r1, #:upper16:__hyp_stub_vectors - 0b
+ add r1, r1, r0 @ PA(stub)
+ mcr p15, 4, r1, c12, c0, 0 @ HVBAR
+ b exit
+
+1: ldr r0, =HVC_STUB_ERR
+ eret
+exit:
+ mov r0, #0
eret
-ENDPROC(__kvm_hyp_reset)
+ENDPROC(__kvm_handle_stub_hvc)
.ltorg
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index b1bd316f14c0..80a1d6cd261c 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -37,10 +37,6 @@
* in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are
* passed in r0 (strictly 32bit).
*
- * A function pointer with a value of 0xffffffff has a special meaning,
- * and is used to implement __hyp_get_vectors in the same way as in
- * arch/arm/kernel/hyp_stub.S.
- *
* The calling convention follows the standard AAPCS:
* r0 - r3: caller save
* r12: caller save
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 962616fd4ddd..313ee646480f 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -292,11 +292,18 @@ static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
phys_addr_t addr = start, end = start + size;
phys_addr_t next;
+ assert_spin_locked(&kvm->mmu_lock);
pgd = kvm->arch.pgd + stage2_pgd_index(addr);
do {
next = stage2_pgd_addr_end(addr, end);
if (!stage2_pgd_none(*pgd))
unmap_stage2_puds(kvm, pgd, addr, next);
+ /*
+ * If the range is too large, release the kvm->mmu_lock
+ * to prevent starvation and lockup detector warnings.
+ */
+ if (next != end)
+ cond_resched_lock(&kvm->mmu_lock);
} while (pgd++, addr = next, addr != end);
}
@@ -803,6 +810,7 @@ void stage2_unmap_vm(struct kvm *kvm)
int idx;
idx = srcu_read_lock(&kvm->srcu);
+ down_read(&current->mm->mmap_sem);
spin_lock(&kvm->mmu_lock);
slots = kvm_memslots(kvm);
@@ -810,6 +818,7 @@ void stage2_unmap_vm(struct kvm *kvm)
stage2_unmap_memslot(kvm, memslot);
spin_unlock(&kvm->mmu_lock);
+ up_read(&current->mm->mmap_sem);
srcu_read_unlock(&kvm->srcu, idx);
}
@@ -829,7 +838,10 @@ void kvm_free_stage2_pgd(struct kvm *kvm)
if (kvm->arch.pgd == NULL)
return;
+ spin_lock(&kvm->mmu_lock);
unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
+ spin_unlock(&kvm->mmu_lock);
+
/* Free the HW pgd, one page at a time */
free_pages_exact(kvm->arch.pgd, S2_PGD_SIZE);
kvm->arch.pgd = NULL;
@@ -1512,7 +1524,8 @@ static int handle_hva_to_gpa(struct kvm *kvm,
unsigned long start,
unsigned long end,
int (*handler)(struct kvm *kvm,
- gpa_t gpa, void *data),
+ gpa_t gpa, u64 size,
+ void *data),
void *data)
{
struct kvm_memslots *slots;
@@ -1524,7 +1537,7 @@ static int handle_hva_to_gpa(struct kvm *kvm,
/* we only care about the pages that the guest sees */
kvm_for_each_memslot(memslot, slots) {
unsigned long hva_start, hva_end;
- gfn_t gfn, gfn_end;
+ gfn_t gpa;
hva_start = max(start, memslot->userspace_addr);
hva_end = min(end, memslot->userspace_addr +
@@ -1532,25 +1545,16 @@ static int handle_hva_to_gpa(struct kvm *kvm,
if (hva_start >= hva_end)
continue;
- /*
- * {gfn(page) | page intersects with [hva_start, hva_end)} =
- * {gfn_start, gfn_start+1, ..., gfn_end-1}.
- */
- gfn = hva_to_gfn_memslot(hva_start, memslot);
- gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
-
- for (; gfn < gfn_end; ++gfn) {
- gpa_t gpa = gfn << PAGE_SHIFT;
- ret |= handler(kvm, gpa, data);
- }
+ gpa = hva_to_gfn_memslot(hva_start, memslot) << PAGE_SHIFT;
+ ret |= handler(kvm, gpa, (u64)(hva_end - hva_start), data);
}
return ret;
}
-static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
+static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
- unmap_stage2_range(kvm, gpa, PAGE_SIZE);
+ unmap_stage2_range(kvm, gpa, size);
return 0;
}
@@ -1577,10 +1581,11 @@ int kvm_unmap_hva_range(struct kvm *kvm,
return 0;
}
-static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data)
+static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
pte_t *pte = (pte_t *)data;
+ WARN_ON(size != PAGE_SIZE);
/*
* We can always call stage2_set_pte with KVM_S2PTE_FLAG_LOGGING_ACTIVE
* flag clear because MMU notifiers will have unmapped a huge PMD before
@@ -1606,11 +1611,12 @@ void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
}
-static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
+static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
pmd_t *pmd;
pte_t *pte;
+ WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
pmd = stage2_get_pmd(kvm, NULL, gpa);
if (!pmd || pmd_none(*pmd)) /* Nothing there */
return 0;
@@ -1625,11 +1631,12 @@ static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
return stage2_ptep_test_and_clear_young(pte);
}
-static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
+static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
pmd_t *pmd;
pte_t *pte;
+ WARN_ON(size != PAGE_SIZE && size != PMD_SIZE);
pmd = stage2_get_pmd(kvm, NULL, gpa);
if (!pmd || pmd_none(*pmd)) /* Nothing there */
return 0;
@@ -1674,11 +1681,6 @@ phys_addr_t kvm_get_idmap_vector(void)
return hyp_idmap_vector;
}
-phys_addr_t kvm_get_idmap_start(void)
-{
- return hyp_idmap_start;
-}
-
static int kvm_map_idmap_text(pgd_t *pgd)
{
int err;
@@ -1801,6 +1803,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
(KVM_PHYS_SIZE >> PAGE_SHIFT))
return -EFAULT;
+ down_read(&current->mm->mmap_sem);
/*
* A memory region could potentially cover multiple VMAs, and any holes
* between them, so iterate over all of them to find out if we can map
@@ -1844,8 +1847,10 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
pa += vm_start - vma->vm_start;
/* IO region dirty page logging not allowed */
- if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES)
- return -EINVAL;
+ if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES) {
+ ret = -EINVAL;
+ goto out;
+ }
ret = kvm_phys_addr_ioremap(kvm, gpa, pa,
vm_end - vm_start,
@@ -1857,7 +1862,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
} while (hva < reg_end);
if (change == KVM_MR_FLAGS_ONLY)
- return ret;
+ goto out;
spin_lock(&kvm->mmu_lock);
if (ret)
@@ -1865,6 +1870,8 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
else
stage2_flush_memslot(kvm, memslot);
spin_unlock(&kvm->mmu_lock);
+out:
+ up_read(&current->mm->mmap_sem);
return ret;
}
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index c2b131527a64..a08d7a93aebb 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -208,9 +208,10 @@ int kvm_psci_version(struct kvm_vcpu *vcpu)
static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
{
- int ret = 1;
+ struct kvm *kvm = vcpu->kvm;
unsigned long psci_fn = vcpu_get_reg(vcpu, 0) & ~((u32) 0);
unsigned long val;
+ int ret = 1;
switch (psci_fn) {
case PSCI_0_2_FN_PSCI_VERSION:
@@ -230,7 +231,9 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
break;
case PSCI_0_2_FN_CPU_ON:
case PSCI_0_2_FN64_CPU_ON:
+ mutex_lock(&kvm->lock);
val = kvm_psci_vcpu_on(vcpu);
+ mutex_unlock(&kvm->lock);
break;
case PSCI_0_2_FN_AFFINITY_INFO:
case PSCI_0_2_FN64_AFFINITY_INFO:
@@ -279,6 +282,7 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
{
+ struct kvm *kvm = vcpu->kvm;
unsigned long psci_fn = vcpu_get_reg(vcpu, 0) & ~((u32) 0);
unsigned long val;
@@ -288,7 +292,9 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
val = PSCI_RET_SUCCESS;
break;
case KVM_PSCI_FN_CPU_ON:
+ mutex_lock(&kvm->lock);
val = kvm_psci_vcpu_on(vcpu);
+ mutex_unlock(&kvm->lock);
break;
default:
val = PSCI_RET_NOT_SUPPORTED;