[PATCH v3 1/2] KVM: arm64: Make ID_AA64MMFR1_EL1.{HCX, TWED} writable from userspace

Jinqian Yang yangjinqian1 at huawei.com
Thu Sep 11 04:46:20 PDT 2025


Allow userspace to downgrade {HCX, TWED} in ID_AA64MMFR1_EL1. Userspace can
only change the value from high to low.

Signed-off-by: Jinqian Yang <yangjinqian1 at huawei.com>
---
 arch/arm64/kvm/sys_regs.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 82ffb3b3b3cf..db49beb8804e 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -3002,8 +3002,6 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 				      ~(ID_AA64MMFR0_EL1_RES0 |
 					ID_AA64MMFR0_EL1_ASIDBITS)),
 	ID_WRITABLE(ID_AA64MMFR1_EL1, ~(ID_AA64MMFR1_EL1_RES0 |
-					ID_AA64MMFR1_EL1_HCX |
-					ID_AA64MMFR1_EL1_TWED |
 					ID_AA64MMFR1_EL1_XNX |
 					ID_AA64MMFR1_EL1_VH |
 					ID_AA64MMFR1_EL1_VMIDBits)),
-- 
2.33.0




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