Re: [PATCH v5 12/23] powerpc/book3s64/pkeys: Inherit correctly on fork.

[Sandipan Das]

On 27/08/20 9:39 am, Aneesh Kumar K.V wrote:
> 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 
> ---
>  arch/powerpc/kernel/process.c | 9 +
>  1 file changed, 9 insertions(+)
> 

Reviewed-by: Sandipan Das 

[PATCH v5 12/23] powerpc/book3s64/pkeys: Inherit correctly on fork.

[Aneesh Kumar K.V]

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 
---
 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 4633924ea77f..725fd1bed2b6 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1732,6 +1732,15 @@ int copy_thread(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