Commit 7c36447a authored by Will Deacon's avatar Will Deacon Committed by Catalin Marinas
Browse files

KVM: arm64: Set SCTLR_EL2.DSSBS if SSBD is forcefully disabled and !vhe 



When running without VHE, it is necessary to set SCTLR_EL2.DSSBS if SSBD
has been forcefully disabled on the kernel command-line.

Acked-by: default avatarChristoffer Dall <christoffer.dall@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 8f04e8e6

arch/arm64/include/asm/kvm_host.h

+11 −0
Original line number Diff line number Diff line
@@ -389,6 +389,8 @@ struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); 


DECLARE_PER_CPU(kvm_cpu_context_t, kvm_host_cpu_state);



void __kvm_enable_ssbs(void);



static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr,

				       unsigned long hyp_stack_ptr,

				       unsigned long vector_ptr)
@@ -409,6 +411,15 @@ static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr, 
	 */

	BUG_ON(!static_branch_likely(&arm64_const_caps_ready));

	__kvm_call_hyp((void *)pgd_ptr, hyp_stack_ptr, vector_ptr, tpidr_el2);



	/*

	 * Disabling SSBD on a non-VHE system requires us to enable SSBS

	 * at EL2.

	 */

	if (!has_vhe() && this_cpu_has_cap(ARM64_SSBS) &&

	    arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) {

		kvm_call_hyp(__kvm_enable_ssbs);

	}

}



static inline bool kvm_arch_check_sve_has_vhe(void)

arch/arm64/kvm/hyp/sysreg-sr.c

+11 −0
Original line number Diff line number Diff line
@@ -288,3 +288,14 @@ void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu) 


	vcpu->arch.sysregs_loaded_on_cpu = false;

}



void __hyp_text __kvm_enable_ssbs(void)

{

	u64 tmp;



	asm volatile(

	"mrs	%0, sctlr_el2\n"

	"orr	%0, %0, %1\n"

	"msr	sctlr_el2, %0"

	: "=&r" (tmp) : "L" (SCTLR_ELx_DSSBS));

}

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