Commit 04e05f05 authored by David Brazdil's avatar David Brazdil Committed by Marc Zyngier
Browse files

KVM: arm64: Add function to enter host from KVM nVHE hyp code 



All nVHE hyp code is currently executed as handlers of host's HVCs. This
will change as nVHE starts intercepting host's PSCI CPU_ON SMCs. The
newly booted CPU will need to initialize EL2 state and then enter the
host. Add __host_enter function that branches into the existing
host state-restoring code after the trap handler would have returned.

Signed-off-by: default avatarDavid Brazdil <dbrazdil@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-21-dbrazdil@google.com
parent f74e1e21

arch/arm64/kvm/hyp/nvhe/host.S

+9 −0
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ SYM_FUNC_START(__host_exit) 
	bl	handle_trap



	/* Restore host regs x0-x17 */

__host_enter_restore_full:

	ldp	x0, x1,   [x29, #CPU_XREG_OFFSET(0)]

	ldp	x2, x3,   [x29, #CPU_XREG_OFFSET(2)]

	ldp	x4, x5,   [x29, #CPU_XREG_OFFSET(4)]
@@ -61,6 +62,14 @@ __host_enter_without_restoring: 
	sb

SYM_FUNC_END(__host_exit)



/*

 * void __noreturn __host_enter(struct kvm_cpu_context *host_ctxt);

 */

SYM_FUNC_START(__host_enter)

	mov	x29, x0

	b	__host_enter_restore_full

SYM_FUNC_END(__host_enter)



/*

 * void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par);

 */