PowerVM systems running compatibility mode on a few Power8 revisions are
still vulnerable to the hardware defect that loses PMU exceptions arriving
prior to a context switch.

The software fix for this issue is enabled through the CPU_FTR_PMAO_BUG
cpu_feature bit, nevertheless this bit also needs to be set for PowerVM
compatibility mode systems.

Fixes: 68f2f0d431d9ea4 ("powerpc: Add a cpu feature CPU_FTR_PMAO_BUG")
Signed-off-by: Desnes A. Nunes do Rosario <desn...@linux.ibm.com>
---
 arch/powerpc/kernel/cputable.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index e745abc5457a..5bfef6263dfb 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -2198,6 +2198,8 @@ static struct cpu_spec * __init setup_cpu_spec(unsigned 
long offset,
                if (old.oprofile_cpu_type != NULL) {
                        t->oprofile_cpu_type = old.oprofile_cpu_type;
                        t->oprofile_type = old.oprofile_type;
+                       if (old.cpu_features & CPU_FTR_PMAO_BUG)
+                               t->cpu_features |= CPU_FTR_PMAO_BUG;
                }
        }
 
-- 
2.21.1

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