On Fri, Oct 09, 2015 at 11:12:24AM +0300, Andrey Ryabinin wrote: > 2015-10-08 22:02 GMT+03:00 Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>: > > --- a/arch/arm64/kernel/image.h > > +++ b/arch/arm64/kernel/image.h > > @@ -59,4 +59,31 @@ > > _kernel_offset_le = DATA_LE64(TEXT_OFFSET); \ > > _kernel_flags_le = DATA_LE64(__HEAD_FLAGS); > > > > +#ifdef CONFIG_EFI > > + > > +/* > > + * The EFI stub has its own symbol namespace prefixed by __efistub_, to > > + * isolate it from the kernel proper. The following symbols are legally > > + * accessed by the stub, so provide some aliases to make them accessible. > > + * Only include data symbols here, or text symbols of functions that are > > + * guaranteed to be safe when executed at another offset than they were > > + * linked at. The routines below are all implemented in assembler in a > > + * position independent manner > > + */ > > +__efistub_memcmp = __pi_memcmp; > > +__efistub_memchr = __pi_memchr; > > +__efistub_memcpy = __pi_memcpy; > > +__efistub_memmove = __pi_memmove; > > +__efistub_memset = __pi_memset; > > +__efistub_strlen = __pi_strlen; > > +__efistub_strcmp = __pi_strcmp; > > +__efistub_strncmp = __pi_strncmp; > > +__efistub___flush_dcache_area = __pi___flush_dcache_area; > > So why we need these __pi_* aliases? > We could just do __efistub_memcmp = memcmp; Right? We *could*, but that defeats the whole purpose of tagging position-independent functions explicitly in the kernel text. Will -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
