From 5e20e3499682c4f1724438d23afcafd473526a54 Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Mon, 24 May 2021 09:29:49 +0100 Subject: [PATCH] arm64: Downgrade flush_icache_range to invalidate Since __flush_dcache_area is called right before, invalidate_icache_range is sufficient in this case. Rewrite the comment to better explain the rationale behind the cache maintenance operations used here. No functional change intended. Possible performance impact due to invalidating only the icache rather than invalidating and cleaning both caches. Reported-by: Catalin Marinas Reported-by: Will Deacon Link: https://lore.kernel.org/linux-arch/20200511110014.lb9PEahJ4hVOYrbwIb_qUHXyNy9KQzNFdb_I3YlzY6A@z/ Acked-by: Mark Rutland Signed-off-by: Fuad Tabba Acked-by: Catalin Marinas Reviewed-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20210524083001.2586635-7-tabba@google.com Signed-off-by: Will Deacon --- arch/arm64/kernel/machine_kexec.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 90a335c744425..a03944fd0cd4e 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -68,10 +68,14 @@ int machine_kexec_post_load(struct kimage *kimage) kimage->arch.kern_reloc = __pa(reloc_code); kexec_image_info(kimage); - /* Flush the reloc_code in preparation for its execution. */ + /* + * For execution with the MMU off, reloc_code needs to be cleaned to the + * PoC and invalidated from the I-cache. + */ __flush_dcache_area(reloc_code, arm64_relocate_new_kernel_size); - flush_icache_range((uintptr_t)reloc_code, (uintptr_t)reloc_code + - arm64_relocate_new_kernel_size); + invalidate_icache_range((uintptr_t)reloc_code, + (uintptr_t)reloc_code + + arm64_relocate_new_kernel_size); return 0; } -- 2.30.2