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

Commit f1b711c6 authored by James Hogan's avatar James Hogan Committed by Ralf Baechle
Browse files

MIPS: KVM/locore.S: Relax noat 



Now that the at register ($1) is no longer saved by
__kvm_mips_vcpu_run(), relax the noat assembler directive so that it
only applies around code where at is restored before entering guest, and
saved after exiting guest.

Signed-off-by: default avatarJames Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13209/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 1300fcd5

arch/mips/kvm/locore.S

+5 −11
Original line number Diff line number Diff line
@@ -48,7 +48,6 @@ 
 * a1: vcpu

 */

	.set	noreorder

	.set	noat



FEXPORT(__kvm_mips_vcpu_run)

	/* k0/k1 not being used in host kernel context */
@@ -145,6 +144,7 @@ FEXPORT(__kvm_mips_load_asid) 
	/* Disable RDHWR access */

	mtc0	zero, CP0_HWRENA



	.set	noat

	/* Now load up the Guest Context from VCPU */

	LONG_L	$1, VCPU_R1(k1)

	LONG_L	$2, VCPU_R2(k1)
@@ -256,6 +256,8 @@ NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) 
	LONG_S	$30, VCPU_R30(k1)

	LONG_S	$31, VCPU_R31(k1)



	.set at



	/* We need to save hi/lo and restore them on the way out */

	mfhi	t0

	LONG_S	t0, VCPU_HI(k1)
@@ -307,9 +309,7 @@ NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) 
	/* load up the host EBASE */

	mfc0	v0, CP0_STATUS



	.set	at

	or	k0, v0, ST0_BEV

	.set	noat



	mtc0	k0, CP0_STATUS

	ehb
@@ -321,7 +321,6 @@ NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) 
	 * If FPU is enabled, save FCR31 and clear it so that later ctc1's don't

	 * trigger FPE for pending exceptions.

	 */

	.set	at

	and	v1, v0, ST0_CU1

	beqz	v1, 1f

	 nop
@@ -331,7 +330,6 @@ NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) 
	sw	t0, VCPU_FCR31(k1)

	ctc1	zero,fcr31

	.set	pop

	.set	noat

1:



#ifdef CONFIG_CPU_HAS_MSA
@@ -354,10 +352,8 @@ NESTED (MIPSX(GuestException), CALLFRAME_SIZ, ra) 
#endif



	/* Now that the new EBASE has been loaded, unset BEV and KSU_USER */

	.set	at

	and	v0, v0, ~(ST0_EXL | KSU_USER | ST0_IE)

	or	v0, v0, ST0_CU0

	.set	noat

	mtc0	v0, CP0_STATUS

	ehb
@@ -424,18 +420,14 @@ __kvm_mips_return_to_guest: 


	/* Switch EBASE back to the one used by KVM */

	mfc0	v1, CP0_STATUS

	.set	at

	or	k0, v1, ST0_BEV

	.set	noat

	mtc0	k0, CP0_STATUS

	ehb

	mtc0	t0, CP0_EBASE



	/* Setup status register for running guest in UM */

	.set	at

	or	v1, v1, (ST0_EXL | KSU_USER | ST0_IE)

	and	v1, v1, ~(ST0_CU0 | ST0_MX)

	.set	noat

	mtc0	v1, CP0_STATUS

	ehb
@@ -464,6 +456,7 @@ __kvm_mips_return_to_guest: 
	/* Disable RDHWR access */

	mtc0	zero, CP0_HWRENA



	.set	noat

	/* load the guest context from VCPU and return */

	LONG_L	$0, VCPU_R0(k1)

	LONG_L	$1, VCPU_R1(k1)
@@ -509,6 +502,7 @@ FEXPORT(__kvm_mips_skip_guest_restore) 
	LONG_L	k1, VCPU_R27(k1)



	eret

	.set	at



__kvm_mips_return_to_host:

	/* EBASE is already pointing to Linux */