arm64: KVM: VHE: Patch out use of HVC (b81125c7) · Commits · 戴 / test

arch/arm64/kvm/hyp.S

+7 −0

Original line number	Diff line number	Diff line
		@@ -17,7 +17,9 @@

		#include <linux/linkage.h>

		#include <asm/alternative.h>
		#include <asm/assembler.h>
		#include <asm/cpufeature.h>

		/*
		* u64 kvm_call_hyp(void *hypfn, ...);
		@@ -38,6 +40,11 @@
		* arch/arm64/kernel/hyp_stub.S.
		*/
		ENTRY(kvm_call_hyp)
		alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
		hvc #0
		ret
		alternative_else
		b __vhe_hyp_call
		nop
		alternative_endif
		ENDPROC(kvm_call_hyp)

+31 −9

Original line number	Diff line number	Diff line
		@@ -38,6 +38,34 @@
		ldp x0, x1, [sp], #16
		.endm

		.macro do_el2_call
		/*
		* Shuffle the parameters before calling the function
		* pointed to in x0. Assumes parameters in x[1,2,3].
		*/
		sub sp, sp, #16
		str lr, [sp]
		mov lr, x0
		mov x0, x1
		mov x1, x2
		mov x2, x3
		blr lr
		ldr lr, [sp]
		add sp, sp, #16
		.endm

		ENTRY(__vhe_hyp_call)
		do_el2_call
		/*
		* We used to rely on having an exception return to get
		* an implicit isb. In the E2H case, we don't have it anymore.
		* rather than changing all the leaf functions, just do it here
		* before returning to the rest of the kernel.
		*/
		isb
		ret
		ENDPROC(__vhe_hyp_call)

		el1_sync: // Guest trapped into EL2
		save_x0_to_x3

		@@ -58,19 +86,13 @@ el1_sync: // Guest trapped into EL2
		mrs x0, vbar_el2
		b 2f

		1: stp lr, xzr, [sp, #-16]!

		1:
		/*
		* Compute the function address in EL2, and shuffle the parameters.
		* Perform the EL2 call
		*/
		kern_hyp_va x0
		mov lr, x0
		mov x0, x1
		mov x1, x2
		mov x2, x3
		blr lr
		do_el2_call

		ldp lr, xzr, [sp], #16
		2: eret

		el1_trap: