When we detect support for 16bit VMID in ID_AA64MMFR1, we set the
VTCR_EL2_VS field to 1 to make use of 16bit vmids. But, with
commit 3a3604bc5eb4 ("arm64: KVM: Switch to C-based stage2 init")
this is broken and we corrupt VTCR_EL2:T0SZ instead of updating the VS
field. VTCR_EL2_VS was actually defined to the field shift (19) and
not the real value for VS. This patch fixes the issue.
Fixes: commit 3a3604bc5eb4 ("arm64: KVM: Switch to C-based stage2 init")
Cc: Christoffer Dall <christoffer.d...@linaro.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
Acked-by: Marc Zyngier <marc.zyng...@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poul...@arm.com>
---
arch/arm64/include/asm/kvm_arm.h | 4 +++-
arch/arm64/include/asm/sysreg.h | 3 +++
arch/arm64/kvm/hyp/s2-setup.c | 6 ++++--
3 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index 0e391db..4150fd8 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -124,7 +124,9 @@
#define VTCR_EL2_SL0_LVL1 (1 << 6)
#define VTCR_EL2_T0SZ_MASK 0x3f
#define VTCR_EL2_T0SZ_40B 24
-#define VTCR_EL2_VS 19
+#define VTCR_EL2_VS_SHIFT 19
+#define VTCR_EL2_VS_8BIT (0 << VTCR_EL2_VS_SHIFT)
+#define VTCR_EL2_VS_16BIT (1 << VTCR_EL2_VS_SHIFT)
/*
* We configure the Stage-2 page tables to always restrict the IPA space to be
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 1a78d6e..1287416 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -141,6 +141,9 @@
#define ID_AA64MMFR1_VMIDBITS_SHIFT 4
#define ID_AA64MMFR1_HADBS_SHIFT 0
+#define ID_AA64MMFR1_VMIDBITS_8 0
+#define ID_AA64MMFR1_VMIDBITS_16 2
+
/* id_aa64mmfr2 */
#define ID_AA64MMFR2_UAO_SHIFT 4
diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c
index bfc54fd..5a9f3bf 100644
--- a/arch/arm64/kvm/hyp/s2-setup.c
+++ b/arch/arm64/kvm/hyp/s2-setup.c
@@ -36,8 +36,10 @@ void __hyp_text __init_stage2_translation(void)
* Read the VMIDBits bits from ID_AA64MMFR1_EL1 and set the VS
* bit in VTCR_EL2.
*/
- tmp = (read_sysreg(id_aa64mmfr1_el1) >> 4) & 0xf;
- val |= (tmp == 2) ? VTCR_EL2_VS : 0;
+ tmp = (read_sysreg(id_aa64mmfr1_el1) >> ID_AA64MMFR1_VMIDBITS_SHIFT) &
0xf;
+ val |= (tmp == ID_AA64MMFR1_VMIDBITS_16) ?
+ VTCR_EL2_VS_16BIT :
+ VTCR_EL2_VS_8BIT;
write_sysreg(val, vtcr_el2);
}
--
1.7.9.5
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