Child thread.kuap value is inherited from the parent in copy_thread_tls. We 
still
need to make sure when the child returns from a fork in the kernel we start 
with the kernel
default AMR value.

Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
---
 arch/powerpc/kernel/process.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 14599c7e4a37..dbce0b1daf2f 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1705,6 +1705,15 @@ int copy_thread_tls(unsigned long clone_flags, unsigned 
long usp,
                childregs->ppr = DEFAULT_PPR;
 
        p->thread.tidr = 0;
+#endif
+       /*
+        * Run with the current AMR value of the kernel
+        */
+#if defined(CONFIG_PPC_MEM_KEYS)
+       if (mmu_has_feature(MMU_FTR_KUAP))
+               kregs->kuap = AMR_KUAP_BLOCKED;
+       if (mmu_has_feature(MMU_FTR_KUEP))
+               kregs->kuep = AMR_KUEP_BLOCKED;
 #endif
        kregs->nip = ppc_function_entry(f);
        return 0;
-- 
2.26.2

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