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-rw-r--r--arch/arm64/include/asm/sysreg.h3
-rw-r--r--arch/arm64/kernel/head.S23
2 files changed, 24 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 1312fb48f18b..2facd7933948 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -575,6 +575,7 @@
#define SCTLR_ELx_DSSBS (BIT(44))
#define SCTLR_ELx_ATA (BIT(43))
+#define SCTLR_ELx_EE_SHIFT 25
#define SCTLR_ELx_ENIA_SHIFT 31
#define SCTLR_ELx_ITFSB (BIT(37))
@@ -583,7 +584,7 @@
#define SCTLR_ELx_LSMAOE (BIT(29))
#define SCTLR_ELx_nTLSMD (BIT(28))
#define SCTLR_ELx_ENDA (BIT(27))
-#define SCTLR_ELx_EE (BIT(25))
+#define SCTLR_ELx_EE (BIT(SCTLR_ELx_EE_SHIFT))
#define SCTLR_ELx_EIS (BIT(22))
#define SCTLR_ELx_IESB (BIT(21))
#define SCTLR_ELx_TSCXT (BIT(20))
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index dc56e1d8f36e..107a2b87577c 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -129,10 +129,31 @@ SYM_CODE_START_LOCAL(record_mmu_state)
mrs x19, sctlr_el1
b.ne 0f
mrs x19, sctlr_el2
-0: tst x19, #SCTLR_ELx_C // Z := (C == 0)
+0:
+CPU_LE( tbnz x19, #SCTLR_ELx_EE_SHIFT, 1f )
+CPU_BE( tbz x19, #SCTLR_ELx_EE_SHIFT, 1f )
+ tst x19, #SCTLR_ELx_C // Z := (C == 0)
and x19, x19, #SCTLR_ELx_M // isolate M bit
csel x19, xzr, x19, eq // clear x19 if Z
ret
+
+ /*
+ * Set the correct endianness early so all memory accesses issued
+ * before init_kernel_el() occur in the correct byte order. Note that
+ * this means the MMU must be disabled, or the active ID map will end
+ * up getting interpreted with the wrong byte order.
+ */
+1: eor x19, x19, #SCTLR_ELx_EE
+ bic x19, x19, #SCTLR_ELx_M
+ b.ne 2f
+ pre_disable_mmu_workaround
+ msr sctlr_el2, x19
+ b 3f
+ pre_disable_mmu_workaround
+2: msr sctlr_el1, x19
+3: isb
+ mov x19, xzr
+ ret
SYM_CODE_END(record_mmu_state)
/*