From 429388682dc266e7a693f9c27e3aabd341d55343 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 22 Jun 2018 09:31:15 +0100 Subject: arm64: Avoid flush_icache_range() in alternatives patching code The implementation of flush_icache_range() includes instruction sequences which are themselves patched at runtime, so it is not safe to call from the patching framework. This patch reworks the alternatives cache-flushing code so that it rolls its own internal D-cache maintenance using DC CIVAC before invalidating the entire I-cache after all alternatives have been applied at boot. Modules don't cause any issues, since flush_icache_range() is safe to call by the time they are loaded. Acked-by: Mark Rutland Reported-by: Rohit Khanna Cc: Alexander Van Brunt Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/module.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'arch/arm64/kernel/module.c') diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index 155fd91e78f4..f0f27aeefb73 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -448,9 +448,8 @@ int module_finalize(const Elf_Ehdr *hdr, const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++) { - if (strcmp(".altinstructions", secstrs + s->sh_name) == 0) { - apply_alternatives((void *)s->sh_addr, s->sh_size); - } + if (strcmp(".altinstructions", secstrs + s->sh_name) == 0) + apply_alternatives_module((void *)s->sh_addr, s->sh_size); #ifdef CONFIG_ARM64_MODULE_PLTS if (IS_ENABLED(CONFIG_DYNAMIC_FTRACE) && !strcmp(".text.ftrace_trampoline", secstrs + s->sh_name)) -- cgit v1.2.3