From: David Brazdil Date: Wed, 2 Dec 2020 18:41:16 +0000 (+0000) Subject: KVM: arm64: Add function to enter host from KVM nVHE hyp code X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=04e05f057a04275cb68c8053b29c5642ae0bad4f;p=linux.git 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: David Brazdil Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201202184122.26046-21-dbrazdil@google.com --- diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S index 2b56f0bdf8743..a820dfdc9c25d 100644 --- a/arch/arm64/kvm/hyp/nvhe/host.S +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -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); */