KVM: PPC: Book3S HV: POWER9 more doorbell fixes

- Add another case where msgsync is required.
- Required barrier sequence for global doorbells is msgsync ; lwsync

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: 1704a81cce ("KVM: PPC: Book3S HV: Use msgsnd for IPIs to other cores on POWER9")
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Nicholas Piggin 2017-10-10 20:18:28 +10:00 committed by Paul Mackerras
parent ac64115a66
commit 2cde371632

View File

@ -1310,6 +1310,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
bne 3f
BEGIN_FTR_SECTION
PPC_MSGSYNC
lwsync
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
lbz r0, HSTATE_HOST_IPI(r13)
cmpwi r0, 0
@ -2788,6 +2789,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
PPC_MSGCLR(6)
/* see if it's a host IPI */
li r3, 1
BEGIN_FTR_SECTION
PPC_MSGSYNC
lwsync
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
lbz r0, HSTATE_HOST_IPI(r13)
cmpwi r0, 0
bnelr