On Wed, Aug 10, 2016 at 12:00:53PM +0200, Arnd Bergmann wrote: > On Wednesday, August 10, 2016 10:43:39 AM CEST Russell King - ARM Linux wrote: > > On Fri, Jun 03, 2016 at 11:40:24AM -0700, Kees Cook wrote: > > > @@ -1309,16 +1309,11 @@ void __init arm_mm_memblock_reserve(void) > > > * Any other function or debugging method which may touch any device _will_ > > > * crash the kernel. > > > */ > > > +static char vectors[PAGE_SIZE * 2] __ro_after_init __aligned(PAGE_SIZE); > > > static void __init devicemaps_init(const struct machine_desc *mdesc) > > > { > > > struct map_desc map; > > > unsigned long addr; > > > - void *vectors; > > > - > > > - /* > > > - * Allocate the vector page early. > > > - */ > > > - vectors = early_alloc(PAGE_SIZE * 2); > > > > This one is not appropriate. We _do_ write to these pages after init > > for FIQ handler updates. See set_fiq_handler(). > > Is that the only thing that modifies the page? If we think this is a > valuable change, we could make it depend on the absence of FIQ > support, as very few platforms (rpc, omap1, s3c24xx and possibly > imx) seem to even use it. There's the TLS emulation too, but that writes via the vectors mapping at 0xffff0ff0. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html