[PATCH v4 26/41] powerpc/book3s64/pkeys: Inherit correctly on fork.
From: Aneesh Kumar K.V <hidden>
Date: 2020-06-15 07:05:49
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
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 <redacted> --- 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