From e10cc8715d180509a367d3ab25d40e4a1612cb2f Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Thu, 9 Jul 2020 08:59:37 +0530 Subject: [PATCH] powerpc/book3s64/kuep: Add MMU_FTR_KUEP This will be used to enable/disable Kernel Userspace Execution Prevention (KUEP). Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200709032946.881753-15-aneesh.kumar@linux.ibm.com --- arch/powerpc/include/asm/mmu.h | 9 +++++++++ arch/powerpc/mm/book3s64/radix_pgtable.c | 4 +++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h index 17cbaf132631..255a1837e9f7 100644 --- a/arch/powerpc/include/asm/mmu.h +++ b/arch/powerpc/include/asm/mmu.h @@ -28,6 +28,11 @@ * Individual features below. */ +/* + * Support for KUEP feature. + */ +#define MMU_FTR_KUEP ASM_CONST(0x00000400) + /* * Support for memory protection keys. */ @@ -189,6 +194,10 @@ enum { #ifdef CONFIG_PPC_MEM_KEYS MMU_FTR_PKEY | #endif +#ifdef CONFIG_PPC_KUEP + MMU_FTR_KUEP | +#endif /* CONFIG_PPC_KUAP */ + 0, }; diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c index c5bf2ef73c36..3536675dd61e 100644 --- a/arch/powerpc/mm/book3s64/radix_pgtable.c +++ b/arch/powerpc/mm/book3s64/radix_pgtable.c @@ -593,8 +593,10 @@ void setup_kuep(bool disabled) if (disabled || !early_radix_enabled()) return; - if (smp_processor_id() == boot_cpuid) + if (smp_processor_id() == boot_cpuid) { pr_info("Activating Kernel Userspace Execution Prevention\n"); + cur_cpu_spec->mmu_features |= MMU_FTR_KUEP; + } /* * Radix always uses key0 of the IAMR to determine if an access is -- 2.49.0