Re: [PATCH v6 11/22] powerpc/book3s64/pkeys: Inherit correctly on fork.
From: Christophe Leroy <hidden>
Date: 2020-11-25 14:16:29
Le 25/11/2020 à 06:16, Aneesh Kumar K.V a écrit :
quoted hunk ↗ jump to hunk
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. Reviewed-by: Sandipan Das <redacted> Signed-off-by: Aneesh Kumar K.V <redacted> --- arch/powerpc/kernel/process.c | 11 +++++++++++ 1 file changed, 11 insertions(+)diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index b6b8a845e454..733680de0ba4 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c@@ -1768,6 +1768,17 @@ 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 + */ +#ifdef CONFIG_PPC_KUAP + if (mmu_has_feature(MMU_FTR_KUAP)) + kregs->kuap = AMR_KUAP_BLOCKED; +#endif
Do we need that ifdef at all ? Shouldn't mmu_has_feature(MMU_FTR_KUAP) be always false and get optimised out when CONFIG_PPC_KUAP is not defined ?
+#ifdef CONFIG_PPC_KUEP + if (mmu_has_feature(MMU_FTR_KUEP)) + kregs->iamr = AMR_KUEP_BLOCKED;
Same ?
#endif kregs->nip = ppc_function_entry(f); return 0;