4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 3c5b1d92b3b02be07873d611a27950addff544d3 ]

Setting TCR_EL2.PS to 40 bits is wrong on systems with less that
less than 40 bits of physical addresses. and breaks KVM on systems
where the RAM is above 40 bits.

This patch uses ID_AA64MMFR0_EL1.PARange to set TCR_EL2.PS dynamically,
just like we already do for VTCR_EL2.PS.

[Marc: rewrote commit message, patch tidy up]

Reviewed-by: Marc Zyngier <[email protected]>
Signed-off-by: Tirumalesh Chalamarla <[email protected]>
Signed-off-by: Marc Zyngier <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 arch/arm64/include/asm/kvm_arm.h |    2 --
 arch/arm64/kvm/hyp-init.S        |   13 ++++++++-----
 2 files changed, 8 insertions(+), 7 deletions(-)

--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -107,8 +107,6 @@
 #define TCR_EL2_MASK   (TCR_EL2_TG0 | TCR_EL2_SH0 | \
                         TCR_EL2_ORGN0 | TCR_EL2_IRGN0 | TCR_EL2_T0SZ)
 
-#define TCR_EL2_FLAGS  (TCR_EL2_RES1 | TCR_EL2_PS_40B)
-
 /* VTCR_EL2 Registers bits */
 #define VTCR_EL2_RES1          (1 << 31)
 #define VTCR_EL2_PS_MASK       (7 << 16)
--- a/arch/arm64/kvm/hyp-init.S
+++ b/arch/arm64/kvm/hyp-init.S
@@ -64,7 +64,7 @@ __do_hyp_init:
        mrs     x4, tcr_el1
        ldr     x5, =TCR_EL2_MASK
        and     x4, x4, x5
-       ldr     x5, =TCR_EL2_FLAGS
+       mov     x5, #TCR_EL2_RES1
        orr     x4, x4, x5
 
 #ifndef CONFIG_ARM64_VA_BITS_48
@@ -85,15 +85,18 @@ __do_hyp_init:
        ldr_l   x5, idmap_t0sz
        bfi     x4, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH
 #endif
-       msr     tcr_el2, x4
-
-       ldr     x4, =VTCR_EL2_FLAGS
        /*
         * Read the PARange bits from ID_AA64MMFR0_EL1 and set the PS bits in
-        * VTCR_EL2.
+        * TCR_EL2 and VTCR_EL2.
         */
        mrs     x5, ID_AA64MMFR0_EL1
        bfi     x4, x5, #16, #3
+
+       msr     tcr_el2, x4
+
+       ldr     x4, =VTCR_EL2_FLAGS
+       bfi     x4, x5, #16, #3
+
        msr     vtcr_el2, x4
 
        mrs     x4, mair_el1


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