On 11/26/14 at 05:23pm, Ard Biesheuvel wrote: > On 26 November 2014 at 10:30, Dave Young <dyoung@xxxxxxxxxx> wrote: > > On 11/18/14 at 01:57pm, Ard Biesheuvel wrote: > >> Improve the handling of /dev/mem mappings under CONFIG_STRICT_DEVMEM by: > >> - allowing read-only access to parts of System RAM that are not > >> considered memory by the kernel, this is mainly intended for exposing > >> UEFI Configuration tables to userland; > > > > Ard, can you elabrate a bit? Are this for the acpi case because no dtb in > > procfs? > > > > No, that is a different issue. > > > Anyway I also think using /dev/mem looks not a good way to expose > > infomation to userspace. > > > > This is for compatibility with existing tools like dmidecode and lshw > that already use /dev/mem. > However, on x86, the tables they access are in iomem resource ranges > that are accessible under CONFIG_STRICT_DEVMEM, whereas on arm64, > those regions are inaccessible. > > So while our position is that using /dev/mem for *anything* is an > awful idea, this particular patch just tries to bring arm64 in line > with what currently existing tools expect. Ard, Ok, thanks for the clarification. -- 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
