From c496433197154144c310a17939736bc5c155914d Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 29 Jun 2020 11:15:22 +0000 Subject: [PATCH] powerpc/32s: Only leave NX unset on segments used for modules Instead of leaving NX unset on all segments above the start of vmalloc space, only leave NX unset on segments used for modules. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/7172c0f5253419315e434a1816ee3d6ed6505bc0.1593428200.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/book3s32/mmu.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c index 03b6ba54460e..c0162911f6cb 100644 --- a/arch/powerpc/mm/book3s32/mmu.c +++ b/arch/powerpc/mm/book3s32/mmu.c @@ -187,6 +187,17 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) return __mmu_mapin_ram(border, top); } +static bool is_module_segment(unsigned long addr) +{ + if (!IS_ENABLED(CONFIG_MODULES)) + return false; + if (addr < ALIGN_DOWN(VMALLOC_START, SZ_256M)) + return false; + if (addr >= ALIGN(VMALLOC_END, SZ_256M)) + return false; + return true; +} + void mmu_mark_initmem_nx(void) { int nb = mmu_has_feature(MMU_FTR_USE_HIGH_BATS) ? 8 : 4; @@ -223,9 +234,9 @@ void mmu_mark_initmem_nx(void) for (i = TASK_SIZE >> 28; i < 16; i++) { /* Do not set NX on VM space for modules */ - if (IS_ENABLED(CONFIG_MODULES) && - (VMALLOC_START & 0xf0000000) == i << 28) - break; + if (is_module_segment(i << 28)) + continue; + mtsrin(mfsrin(i << 28) | 0x10000000, i << 28); } }