[PATCH v4 17/20] arm64: transfer permission indirection settings to EL2

Joey Gouly joey.gouly at arm.com
Tue Jun 6 07:58:56 PDT 2023


Copy the EL1 registers: TCR2_EL1, PIR_EL1, PIRE0_EL1, such that PIE
is also enabled for EL2.

Signed-off-by: Joey Gouly <joey.gouly at arm.com>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Oliver Upton <oliver.upton at linux.dev>
Reviewed-by: Catalin Marinas <catalin.marinas at arm.com>
---
 arch/arm64/kernel/hyp-stub.S | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S
index 9439240c3fcf..d63de1973ddb 100644
--- a/arch/arm64/kernel/hyp-stub.S
+++ b/arch/arm64/kernel/hyp-stub.S
@@ -119,6 +119,24 @@ SYM_CODE_START_LOCAL(__finalise_el2)
 	msr	ttbr1_el1, x0
 	mrs_s	x0, SYS_MAIR_EL12
 	msr	mair_el1, x0
+	mrs	x1, REG_ID_AA64MMFR3_EL1
+	ubfx	x1, x1, #ID_AA64MMFR3_EL1_TCRX_SHIFT, #4
+	cbz	x1, .Lskip_tcr2
+	mrs	x0, REG_TCR2_EL12
+	msr	REG_TCR2_EL1, x0
+
+	// Transfer permission indirection state
+	mrs	x1, REG_ID_AA64MMFR3_EL1
+	ubfx	x1, x1, #ID_AA64MMFR3_EL1_S1PIE_SHIFT, #4
+	cbz	x1, .Lskip_indirection
+	mrs	x0, REG_PIRE0_EL12
+	msr	REG_PIRE0_EL1, x0
+	mrs	x0, REG_PIR_EL12
+	msr	REG_PIR_EL1, x0
+
+.Lskip_indirection:
+.Lskip_tcr2:
+
 	isb
 
 	// Hack the exception return to stay at EL2
-- 
2.25.1




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