diff mbox series

[12/18] arm64: kexec: relocate in EL1 mode

Message ID 20210527150526.271941-13-pasha.tatashin@soleen.com (mailing list archive)
State New, archived
Headers show
Series arm64: MMU enabled kexec relocation | expand

Commit Message

Pavel Tatashin May 27, 2021, 3:05 p.m. UTC
Since we are going to keep MMU enabled during relocation, we need to
keep EL1 mode throughout the relocation.

Keep EL1 enabled, and switch EL2 only before enterying the new world.

Suggested-by: James Morse <james.morse@arm.com>
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
---
 arch/arm64/kernel/cpu-reset.h       |  3 +--
 arch/arm64/kernel/machine_kexec.c   |  4 ++--
 arch/arm64/kernel/relocate_kernel.S | 13 +++++++++++--
 3 files changed, 14 insertions(+), 6 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm64/kernel/cpu-reset.h b/arch/arm64/kernel/cpu-reset.h
index 48d0ed48c147..296abbac7192 100644
--- a/arch/arm64/kernel/cpu-reset.h
+++ b/arch/arm64/kernel/cpu-reset.h
@@ -20,11 +20,10 @@  static inline void __noreturn __nocfi cpu_soft_restart(unsigned long entry,
 {
 	typeof(__cpu_soft_restart) *restart;
 
-	unsigned long el2_switch = is_hyp_callable();
 	restart = (void *)__pa_symbol(function_nocfi(__cpu_soft_restart));
 
 	cpu_install_idmap();
-	restart(el2_switch, entry, arg0, arg1, arg2);
+	restart(0, entry, arg0, arg1, arg2);
 	unreachable();
 }
 
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 9f74791cb1d0..c9993f029262 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -231,8 +231,8 @@  void machine_kexec(struct kimage *kimage)
 	} else {
 		if (is_hyp_callable())
 			__hyp_set_vectors(kimage->arch.el2_vectors);
-		cpu_soft_restart(kimage->arch.kern_reloc, virt_to_phys(kimage),
-				 0, 0);
+		cpu_soft_restart(kimage->arch.kern_reloc,
+				 virt_to_phys(kimage), 0, 0);
 	}
 
 	BUG(); /* Should never get here. */
diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S
index 36b4496524c3..df023b82544b 100644
--- a/arch/arm64/kernel/relocate_kernel.S
+++ b/arch/arm64/kernel/relocate_kernel.S
@@ -13,6 +13,7 @@ 
 #include <asm/kexec.h>
 #include <asm/page.h>
 #include <asm/sysreg.h>
+#include <asm/virt.h>
 
 /*
  * arm64_relocate_new_kernel - Put a 2nd stage image in place and boot it.
@@ -61,12 +62,20 @@  SYM_CODE_START(arm64_relocate_new_kernel)
 	isb
 
 	/* Start new image. */
+	ldr	x1, [x0, #KIMAGE_ARCH_EL2_VECTORS]	/* relocation start */
+	cbz	x1, .Lel1
+	ldr	x1, [x0, #KIMAGE_START]		/* relocation start */
+	ldr	x2, [x0, #KIMAGE_ARCH_DTB_MEM]	/* dtb address */
+	mov	x3, xzr
+	mov	x4, xzr
+	mov     x0, #HVC_SOFT_RESTART
+	hvc	#0				/* Jumps from el2 */
+.Lel1:
 	ldr	x4, [x0, #KIMAGE_START]		/* relocation start */
 	ldr	x0, [x0, #KIMAGE_ARCH_DTB_MEM]	/* dtb address */
-	mov	x1, xzr
 	mov	x2, xzr
 	mov	x3, xzr
-	br	x4
+	br	x4				/* Jumps from el1 */
 SYM_CODE_END(arm64_relocate_new_kernel)
 
 .align 3	/* To keep the 64-bit values below naturally aligned. */