From 71a5b3db9f209ea5d1e07371017e65398d3c6fbc Mon Sep 17 00:00:00 2001 From: Jordan Niethe Date: Wed, 9 Jun 2021 11:34:24 +1000 Subject: powerpc/lib/code-patching: Set up Strict RWX patching earlier setup_text_poke_area() is a late init call so it runs before mark_rodata_ro() and after the init calls. This lets all the init code patching simply write to their locations. In the future, kprobes is going to allocate its instruction pages RO which means they will need setup_text__poke_area() to have been already called for their code patching. However, init_kprobes() (which allocates and patches some instruction pages) is an early init call so it happens before setup_text__poke_area(). start_kernel() calls poking_init() before any of the init calls. On powerpc, poking_init() is currently a nop. setup_text_poke_area() relies on kernel virtual memory, cpu hotplug and per_cpu_areas being setup. setup_per_cpu_areas(), boot_cpu_hotplug_init() and mm_init() are called before poking_init(). Turn setup_text_poke_area() into poking_init(). Signed-off-by: Jordan Niethe Reviewed-by: Christophe Leroy Reviewed-by: Russell Currey [mpe: Fold in missing prototype for poking_init() from lkp] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210609013431.9805-3-jniethe5@gmail.com --- arch/powerpc/include/asm/pgtable.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc/include/asm') diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index b9c8641654f4..b1e6c9ee3206 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -76,6 +76,7 @@ extern unsigned long empty_zero_page[]; extern pgd_t swapper_pg_dir[]; extern void paging_init(void); +void poking_init(void); extern unsigned long ioremap_bot; -- cgit