Commit bd0fdb19 authored Mar 13, 2017 by Nicholas Piggin Committed by Paul Mackerras Aug 24, 2017

KVM: PPC: Book3S HV: Use msgsync with hypervisor doorbells on POWER9



When msgsnd is used for IPIs to other cores, msgsync must be executed by
the target to order stores performed on the source before its msgsnd
(provided the source executes the appropriate sync).

Fixes: 1704a81c ("KVM: PPC: Book3S HV: Use msgsnd for IPIs to other cores on POWER9")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

parent f2d8421b

arch/powerpc/kvm/book3s_hv_rmhandlers.S

+3 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1291,6 +1291,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
	/* Hypervisor doorbell - exit only if host IPI flag set */		/* Hypervisor doorbell - exit only if host IPI flag set */
	cmpwi r12, BOOK3S_INTERRUPT_H_DOORBELL		cmpwi r12, BOOK3S_INTERRUPT_H_DOORBELL
	bne 3f		bne 3f
			BEGIN_FTR_SECTION
			PPC_MSGSYNC
			END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
	lbz r0, HSTATE_HOST_IPI(r13)		lbz r0, HSTATE_HOST_IPI(r13)
	cmpwi r0, 0		cmpwi r0, 0
	beq 4f		beq 4f