[PATCH 04/17] arm64: Prevent the use of is_kernel_in_hyp_mode() in hypervisor code

[Marc Zyngier]

Using is_kernel_in_hyp_mode() in hypervisor code is a pretty bad
mistake. This helper only checks for CurrentEL being EL2, which
is always true.

Make the link fail if using the helper in hypervisor context
by referencing a non-existent function. Whilst we're at it,
flag the helper as __always_inline, which it really should be.

Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 arch/arm64/include/asm/virt.h | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
index b11a1c8c8b36..5f84a87a6a2d 100644
--- a/arch/arm64/include/asm/virt.h
+++ b/arch/arm64/include/asm/virt.h
@@ -110,8 +110,13 @@ static inline bool is_hyp_mode_mismatched(void)
 	return __boot_cpu_mode[0] != __boot_cpu_mode[1];
 }
 
-static inline bool is_kernel_in_hyp_mode(void)
+extern void gotcha_is_kernel_in_hyp_mode(void);
+
+static __always_inline bool is_kernel_in_hyp_mode(void)
 {
+#if defined(__KVM_NVHE_HYPERVISOR__) || defined(__KVM_VHE_HYPERVISOR__)
+	gotcha_is_kernel_in_hyp_mode();
+#endif
 	return read_sysreg(CurrentEL) == CurrentEL_EL2;
 }
 
-- 
2.34.1