linux-kernel - [PATCH v15 01/15] arm64: kernel: add helper for booted at EL2 and not VHE

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Date:   Tue,  8 Jun 2021 20:44:05 -0400
From:   Pavel Tatashin <pasha.tatashin@...een.com>
To:     pasha.tatashin@...een.com, jmorris@...ei.org, sashal@...nel.org,
        ebiederm@...ssion.com, kexec@...ts.infradead.org,
        linux-kernel@...r.kernel.org, corbet@....net,
        catalin.marinas@....com, will@...nel.org,
        linux-arm-kernel@...ts.infradead.org, maz@...nel.org,
        james.morse@....com, vladimir.murzin@....com,
        matthias.bgg@...il.com, linux-mm@...ck.org, mark.rutland@....com,
        steve.capper@....com, rfontana@...hat.com, tglx@...utronix.de,
        selindag@...il.com, tyhicks@...ux.microsoft.com,
        kernelfans@...il.com, akpm@...ux-foundation.org,
        madvenka@...ux.microsoft.com
Subject: [PATCH v15 01/15] arm64: kernel: add helper for booted at EL2 and not VHE

Replace places that contain logic like this:
	is_hyp_mode_available() && !is_kernel_in_hyp_mode()

With a dedicated boolean function  is_hyp_nvhe(). This will be needed
later in kexec in order to sooner switch back to EL2.

Suggested-by: James Morse <james.morse@....com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@...een.com>
---
 arch/arm64/include/asm/virt.h | 5 +++++
 arch/arm64/kernel/cpu-reset.h | 3 +--
 arch/arm64/kernel/hibernate.c | 2 +-
 arch/arm64/kernel/sdei.c      | 2 +-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h
index 7379f35ae2c6..a9457e96203c 100644
--- a/arch/arm64/include/asm/virt.h
+++ b/arch/arm64/include/asm/virt.h
@@ -128,6 +128,11 @@ static __always_inline bool is_protected_kvm_enabled(void)
 		return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE);
 }
 
+static inline bool is_hyp_nvhe(void)
+{
+	return is_hyp_mode_available() && !is_kernel_in_hyp_mode();
+}
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* ! __ASM__VIRT_H */
diff --git a/arch/arm64/kernel/cpu-reset.h b/arch/arm64/kernel/cpu-reset.h
index 9a7b1262ef17..81b3d0fe7a63 100644
--- a/arch/arm64/kernel/cpu-reset.h
+++ b/arch/arm64/kernel/cpu-reset.h
@@ -20,8 +20,7 @@ static inline void __noreturn __nocfi cpu_soft_restart(unsigned long entry,
 {
 	typeof(__cpu_soft_restart) *restart;
 
-	unsigned long el2_switch = !is_kernel_in_hyp_mode() &&
-		is_hyp_mode_available();
+	unsigned long el2_switch = is_hyp_nvhe();
 	restart = (void *)__pa_symbol(function_nocfi(__cpu_soft_restart));
 
 	cpu_install_idmap();
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index b1cef371df2b..42b5d8105ab9 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -49,7 +49,7 @@
 extern int in_suspend;
 
 /* Do we need to reset el2? */
-#define el2_reset_needed() (is_hyp_mode_available() && !is_kernel_in_hyp_mode())
+#define el2_reset_needed() (is_hyp_nvhe())
 
 /* temporary el2 vectors in the __hibernate_exit_text section. */
 extern char hibernate_el2_vectors[];
diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c
index 2c7ca449dd51..cf06929c44e3 100644
--- a/arch/arm64/kernel/sdei.c
+++ b/arch/arm64/kernel/sdei.c
@@ -200,7 +200,7 @@ unsigned long sdei_arch_get_entry_point(int conduit)
 	 * dropped to EL1 because we don't support VHE, then we can't support
 	 * SDEI.
 	 */
-	if (is_hyp_mode_available() && !is_kernel_in_hyp_mode()) {
+	if (is_hyp_nvhe()) {
 		pr_err("Not supported on this hardware/boot configuration\n");
 		goto out_err;
 	}
-- 
2.25.1