diff options
| author | Jordan Niethe <jniethe5@gmail.com> | 2019-12-06 14:17:22 +1100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-01-26 00:11:37 +1100 |
| commit | 736bcdd3a9fc672af33fb83230ecd0570ec38ec6 (patch) | |
| tree | 46b27cba94fa34092b40826832ad1a41189d1b22 /arch/powerpc/kvm | |
| parent | 5649607a8d0b0e019a4db14aab3de1e16c3a2b4f (diff) | |
powerpc/mm: Remove kvm radix prefetch workaround for Power9 DD2.2
Commit a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with
KVM") introduced a number of workarounds as coming out of a guest with
the mmu enabled would make the cpu would start running in hypervisor
state with the PID value from the guest. The cpu will then start
prefetching for the hypervisor with that PID value.
In Power9 DD2.2 the cpu behaviour was modified to fix this. When
accessing Quadrant 0 in hypervisor mode with LPID != 0 prefetching will
not be performed. This means that we can get rid of the workarounds for
Power9 DD2.2 and later revisions. Add a new cpu feature
CPU_FTR_P9_RADIX_PREFETCH_BUG to indicate if the workarounds are needed.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191206031722.25781-1-jniethe5@gmail.com
Diffstat (limited to 'arch/powerpc/kvm')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index c6fbbd29bd87..dbc2fecc37f0 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1801,6 +1801,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) tlbsync ptesync +BEGIN_FTR_SECTION /* Radix: Handle the case where the guest used an illegal PID */ LOAD_REG_ADDR(r4, mmu_base_pid) lwz r3, VCPU_GUEST_PID(r9) @@ -1830,6 +1831,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300) addi r7,r7,0x1000 bdnz 1b ptesync +END_FTR_SECTION_IFSET(CPU_FTR_P9_RADIX_PREFETCH_BUG) 2: #endif /* CONFIG_PPC_RADIX_MMU */ |