On 27 January 2016 at 20:35, Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> wrote: > On Wed, 27 Jan 2016 11:55:23 +0100 Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> wrote: > >> Instead of using absolute addresses for both the exception location >> and the fixup, use offsets relative to the exception table entry values. >> Not only does this cut the size of the exception table in half, it is >> also a prerequisite for KASLR, since absolute exception table entries >> are subject to dynamic relocation, which is incompatible with the sorting >> of the exception table that occurs at build time. >> >> This patch also introduces the _ASM_EXTABLE preprocessor macro (which >> exists on x86 as well) and its _asm_extable assembly counterpart, as >> shorthands to emit exception table entries. > > checkpatch speaketh truth: > > ERROR: #define of 'ARCH_HAS_RELATIVE_EXTABLE' is wrong - use Kconfig variables or standard guards instead > #113: FILE: arch/arm64/include/asm/uaccess.h:56: That may be true, but it extends an established pattern of #defines in the various uaccess.h versions, i.e., ARCH_HAS_SORT_EXTABLE, and ARCH_HAS_SEARCH_EXTABLE -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
