Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 067b8175 authored by James Morse's avatar James Morse Committed by Greg Kroah-Hartman
Browse files

KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated 



commit a5905d6af492ee6a4a2205f0d550b3f931b03d03 upstream.

KVM allows the guest to discover whether the ARCH_WORKAROUND SMCCC are
implemented, and to preserve that state during migration through its
firmware register interface.

Add the necessary boiler plate for SMCCC_ARCH_WORKAROUND_3.

Reviewed-by: default avatarRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
[ kvm code moved to virt/kvm/arm, removed fw regs ABI. Added 32bit stub ]
Signed-off-by: default avatarJames Morse <james.morse@arm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 3e390412

arch/arm/include/asm/kvm_host.h

+6 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <asm/kvm_asm.h>

#include <asm/kvm_mmio.h>

#include <asm/fpstate.h>

#include <asm/spectre.h>

#include <kvm/arm_arch_timer.h>



#define __KVM_HAVE_ARCH_INTC_INITIALIZED
@@ -324,4 +325,9 @@ static inline int kvm_arm_have_ssbd(void) 
	return KVM_SSBD_UNKNOWN;

}



static inline int kvm_arm_get_spectre_bhb_state(void)

{

	/* 32bit guests don't need firmware for this */

	return SPECTRE_VULNERABLE; /* aka SMCCC_RET_NOT_SUPPORTED */

}

#endif /* __ARM_KVM_HOST_H__ */

arch/arm64/include/asm/kvm_host.h

+5 −0
Original line number Diff line number Diff line
@@ -450,4 +450,9 @@ static inline int kvm_arm_have_ssbd(void) 
	}

}



static inline enum mitigation_state kvm_arm_get_spectre_bhb_state(void)

{

	return arm64_get_spectre_bhb_state();

}



#endif /* __ARM64_KVM_HOST_H__ */

virt/kvm/arm/psci.c

+12 −0
Original line number Diff line number Diff line
@@ -433,6 +433,18 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) 
				break;

			}

			break;

		case ARM_SMCCC_ARCH_WORKAROUND_3:

			switch (kvm_arm_get_spectre_bhb_state()) {

			case SPECTRE_VULNERABLE:

				break;

			case SPECTRE_MITIGATED:

				val = SMCCC_RET_SUCCESS;

				break;

			case SPECTRE_UNAFFECTED:

				val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;

				break;

			}

			break;

		}

		break;

	default: