diff options
| author | Paul Mackerras <paulus@ozlabs.org> | 2017-08-25 19:52:12 +1000 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2017-08-31 12:36:44 +1000 |
| commit | a4faf2e77a565432278430deaaba2f3295b6a2df (patch) | |
| tree | f96031bb8a27ddab4a71daf97d25975437812c22 /arch/powerpc/kvm | |
| parent | 0bfa33c7f71e7e9de289582d9652110daa1ec8a1 (diff) | |
KVM: PPC: Book3S HV: Fix case where HDEC is treated as 32-bit on POWER9
Commit 2f2724630f7a ("KVM: PPC: Book3S HV: Cope with host using large
decrementer mode", 2017-05-22) added code to treat the hypervisor
decrementer (HDEC) as a 64-bit value on POWER9 rather than 32-bit.
Unfortunately, that commit missed one place where HDEC is treated
as a 32-bit value. This fixes it.
This bug should not have any user-visible consequences that I can
think of, beyond an occasional unnecessary exit to the host kernel.
If the hypervisor decrementer has gone negative, then the bottom
32 bits will be negative for about 4 seconds after that, so as
long as we get out of the guest within those 4 seconds we won't
conclude that the HDEC interrupt is spurious.
Reported-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Fixes: 2f2724630f7a ("KVM: PPC: Book3S HV: Cope with host using large decrementer mode")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Diffstat (limited to 'arch/powerpc/kvm')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 0bc400f882f4..29ec462d11c5 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1280,7 +1280,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) cmpwi r12,BOOK3S_INTERRUPT_HV_DECREMENTER bne 2f mfspr r3,SPRN_HDEC - cmpwi r3,0 + EXTEND_HDEC(r3) + cmpdi r3,0 mr r4,r9 bge fast_guest_return 2: |