From 1bb2bae2e6c7d94e3bc1fdce06baf31b8d811ed6 Mon Sep 17 00:00:00 2001 From: Russell Currey Date: Thu, 18 Apr 2019 16:51:22 +1000 Subject: [PATCH] powerpc/mm/radix: Use KUEP API for Radix MMU Execution protection already exists on radix, this just refactors the radix init to provide the KUEP setup function instead. Thus, the only functional change is that it can now be disabled. Signed-off-by: Russell Currey Signed-off-by: Michael Ellerman --- arch/powerpc/mm/pgtable-radix.c | 12 +++++++++--- arch/powerpc/platforms/Kconfig.cputype | 1 + 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index 154472a28c77..8616b291bcec 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -531,8 +531,15 @@ static void radix_init_amor(void) mtspr(SPRN_AMOR, (3ul << 62)); } -static void radix_init_iamr(void) +#ifdef CONFIG_PPC_KUEP +void setup_kuep(bool disabled) { + if (disabled || !early_radix_enabled()) + return; + + if (smp_processor_id() == boot_cpuid) + pr_info("Activating Kernel Userspace Execution Prevention\n"); + /* * Radix always uses key0 of the IAMR to determine if an access is * allowed. We set bit 0 (IBM bit 1) of key0, to prevent instruction @@ -540,6 +547,7 @@ static void radix_init_iamr(void) */ mtspr(SPRN_IAMR, (1ul << 62)); } +#endif void __init radix__early_init_mmu(void) { @@ -601,7 +609,6 @@ void __init radix__early_init_mmu(void) memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); - radix_init_iamr(); radix_init_pgtable(); /* Switch to the guard PID before turning on MMU */ radix__switch_mmu_context(NULL, &init_mm); @@ -623,7 +630,6 @@ void radix__early_init_mmu_secondary(void) __pa(partition_tb) | (PATB_SIZE_SHIFT - 12)); radix_init_amor(); } - radix_init_iamr(); radix__switch_mmu_context(NULL, &init_mm); if (cpu_has_feature(CPU_FTR_HVMODE)) diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype index 457fc3a5ed93..60371784c9f1 100644 --- a/arch/powerpc/platforms/Kconfig.cputype +++ b/arch/powerpc/platforms/Kconfig.cputype @@ -326,6 +326,7 @@ config PPC_RADIX_MMU bool "Radix MMU Support" depends on PPC_BOOK3S_64 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA + select PPC_HAVE_KUEP default y help Enable support for the Power ISA 3.0 Radix style MMU. Currently this