From c88b093693ccbe41991ef2e9b1d251945e6e54ed Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Thu, 21 Feb 2019 11:42:32 +0000 Subject: [PATCH] arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2 Due to what looks like a typo dating back to the original addition of FPEXC32_EL2 handling, KVM currently initialises this register to an architecturally invalid value. As a result, the VECITR field (RES1) in bits [10:8] is initialised with 0, and the two reserved (RES0) bits [6:5] are initialised with 1. (In the Common VFP Subarchitecture as specified by ARMv7-A, these two bits were IMP DEF. ARMv8-A removes them.) This patch changes the reset value from 0x70 to 0x700, which reflects the architectural constraints and is presumably what was originally intended. Cc: # 4.12.x- Cc: Christoffer Dall Fixes: 62a89c44954f ("arm64: KVM: 32bit handling of coprocessor traps") Signed-off-by: Dave Martin Signed-off-by: Marc Zyngier --- arch/arm64/kvm/sys_regs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 81a3426..a398d04 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1523,7 +1523,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_DACR32_EL2), NULL, reset_unknown, DACR32_EL2 }, { SYS_DESC(SYS_IFSR32_EL2), NULL, reset_unknown, IFSR32_EL2 }, - { SYS_DESC(SYS_FPEXC32_EL2), NULL, reset_val, FPEXC32_EL2, 0x70 }, + { SYS_DESC(SYS_FPEXC32_EL2), NULL, reset_val, FPEXC32_EL2, 0x700 }, }; static bool trap_dbgidr(struct kvm_vcpu *vcpu, -- 2.7.4