The hyp exit handling logic is largely shared between VHE and nVHE/hVHE,
with common logic in arch/arm64/kvm/hyp/include/hyp/switch.h. The code
in the header depends on function definitions provided by
arch/arm64/kvm/hyp/vhe/switch.c and arch/arm64/kvm/hyp/nvhe/switch.c
when they include the header.
This is an unusual header dependency, and prevents the use of
arch/arm64/kvm/hyp/include/hyp/switch.h in other files as this would
result in compiler warnings regarding missing definitions, e.g.
| In file included from arch/arm64/kvm/hyp/nvhe/hyp-main.c:8:
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:733:31: warning: 'kvm_get_exit_handler_array' used but never defined
| 733 | static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu);
| | ^~~~~~~~~~~~~~~~~~~~~~~~~~
| ./arch/arm64/kvm/hyp/include/hyp/switch.h:735:13: warning: 'early_exit_filter' used but never defined
| 735 | static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code);
| | ^~~~~~~~~~~~~~~~~
Refactor the logic such that the header doesn't depend on anything from
the C files. There should be no functional change as a result of this
patch.
Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Fuad Tabba <tabba@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Oliver Upton <oliver.upton@xxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
arch/arm64/kvm/hyp/include/hyp/switch.h | 30 +++++--------------------
arch/arm64/kvm/hyp/nvhe/switch.c | 30 ++++++++++++++-----------
arch/arm64/kvm/hyp/vhe/switch.c | 9 ++++----
3 files changed, 27 insertions(+), 42 deletions(-)
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h
index c5b8a11ac4f50..46df5c2eeaf57 100644
--- a/arch/arm64/kvm/hyp/include/hyp/switch.h
+++ b/arch/arm64/kvm/hyp/include/hyp/switch.h
@@ -679,23 +679,16 @@ static bool kvm_hyp_handle_dabt_low(struct kvm_vcpu *vcpu, u64 *exit_code)
typedef bool (*exit_handler_fn)(struct kvm_vcpu *, u64 *);
-static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu);
-
-static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code);
-
/*
* Allow the hypervisor to handle the exit with an exit handler if it has one.
*
* Returns true if the hypervisor handled the exit, and control should go back
* to the guest, or false if it hasn't.
*/
-static inline bool kvm_hyp_handle_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
+static inline bool kvm_hyp_handle_exit(struct kvm_vcpu *vcpu, u64 *exit_code,
+ const exit_handler_fn *handlers)
{
- const exit_handler_fn *handlers = kvm_get_exit_handler_array(vcpu);
- exit_handler_fn fn;
-
- fn = handlers[kvm_vcpu_trap_get_class(vcpu)];
-
+ exit_handler_fn fn = handlers[kvm_vcpu_trap_get_class(vcpu)];
if (fn)
return fn(vcpu, exit_code);
@@ -725,20 +718,9 @@ static inline void synchronize_vcpu_pstate(struct kvm_vcpu *vcpu, u64 *exit_code
* the guest, false when we should restore the host state and return to the
* main run loop.
*/
-static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
+static inline bool __fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code,
+ const exit_handler_fn *handlers)
{
- /*
- * Save PSTATE early so that we can evaluate the vcpu mode
- * early on.
- */
- synchronize_vcpu_pstate(vcpu, exit_code);
-
- /*
- * Check whether we want to repaint the state one way or
- * another.
- */
- early_exit_filter(vcpu, exit_code);
-
if (ARM_EXCEPTION_CODE(*exit_code) != ARM_EXCEPTION_IRQ)
vcpu->arch.fault.esr_el2 = read_sysreg_el2(SYS_ESR);
@@ -768,7 +750,7 @@ static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
goto exit;
/* Check if there's an exit handler and allow it to handle the exit. */
- if (kvm_hyp_handle_exit(vcpu, exit_code))
+ if (kvm_hyp_handle_exit(vcpu, exit_code, handlers))
goto guest;
exit:
/* Return to the host kernel and handle the exit */
diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 5d79f63a4f861..324b62329c10b 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -250,20 +250,22 @@ static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu)
return hyp_exit_handlers;
}
-/*
- * Some guests (e.g., protected VMs) are not be allowed to run in AArch32.
- * The ARMv8 architecture does not give the hypervisor a mechanism to prevent a
- * guest from dropping to AArch32 EL0 if implemented by the CPU. If the
- * hypervisor spots a guest in such a state ensure it is handled, and don't
- * trust the host to spot or fix it. The check below is based on the one in
- * kvm_arch_vcpu_ioctl_run().
- *
- * Returns false if the guest ran in AArch32 when it shouldn't have, and
- * thus should exit to the host, or true if a the guest run loop can continue.
- */
-static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code)
+static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
{
- if (unlikely(vcpu_is_protected(vcpu) && vcpu_mode_is_32bit(vcpu))) {
+ const exit_handler_fn *handlers = kvm_get_exit_handler_array(vcpu);
+
+ synchronize_vcpu_pstate(vcpu, exit_code);
+
+ /*
+ * Some guests (e.g., protected VMs) are not be allowed to run in
+ * AArch32. The ARMv8 architecture does not give the hypervisor a
+ * mechanism to prevent a guest from dropping to AArch32 EL0 if
+ * implemented by the CPU. If the hypervisor spots a guest in such a
+ * state ensure it is handled, and don't trust the host to spot or fix
+ * it. The check below is based on the one in
+ * kvm_arch_vcpu_ioctl_run().
+ */
+ if (unlikely(vcpu_is_protected(vcpu) && vcpu_mode_is_32bit(vcpu))) {
/*
* As we have caught the guest red-handed, decide that it isn't
* fit for purpose anymore by making the vcpu invalid. The VMM
@@ -275,6 +277,8 @@ static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code)
*exit_code &= BIT(ARM_EXIT_WITH_SERROR_BIT);
*exit_code |= ARM_EXCEPTION_IL;
}
+
+ return __fixup_guest_exit(vcpu, exit_code, handlers);
}
/* Switch to the guest for legacy non-VHE systems */
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 4748b1947ffa0..c854d84458892 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -540,13 +540,10 @@ static const exit_handler_fn hyp_exit_handlers[] = {
[ESR_ELx_EC_MOPS] = kvm_hyp_handle_mops,
};
-static const exit_handler_fn *kvm_get_exit_handler_array(struct kvm_vcpu *vcpu)
+static inline bool fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
{
- return hyp_exit_handlers;
-}
+ synchronize_vcpu_pstate(vcpu, exit_code);
-static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code)
-{
/*
* If we were in HYP context on entry, adjust the PSTATE view
* so that the usual helpers work correctly.
@@ -566,6 +563,8 @@ static void early_exit_filter(struct kvm_vcpu *vcpu, u64 *exit_code)
*vcpu_cpsr(vcpu) &= ~(PSR_MODE_MASK | PSR_MODE32_BIT);
*vcpu_cpsr(vcpu) |= mode;
}
+
+ return __fixup_guest_exit(vcpu, exit_code, hyp_exit_handlers);
}
/* Switch to the guest for VHE systems running in EL2 */
--
2.30.2
