On Wed, 2013-01-02 at 15:09 -0600, Robin Holt wrote: > On Wed, Jan 02, 2013 at 01:13:43PM -0600, Nathan Zimmer wrote: > > On 01/02/2013 12:04 PM, H. Peter Anvin wrote: > > >On 01/02/2013 09:21 AM, Nathan Zimmer wrote: > > >>I am getting an early boot problem. It only happens on the larger of the > > >>machines I haven't seen it crop up on machines with more then 512 GB of ram. > > >>It shows in the latest linus kernel too. > > >> > > >>I am (wildly) guessing that what is happening is that the new_memmap that is > > >>being passed to bios is somehow placed incorrectly. > > >>I have come up with a workaround. By placing it the DMA area the issue goes > > >>away but that doesn't seem like a real fix. > > >> > > >What does your memory map look like? > > We reported this a few times (Russ Anderson and I both). The problem is > at the point in boot where the efi_enter_virtual_mode callback is, there > is no identity mapping for most of memory. If the allocation happens > to be above the 512GB (or maybe something lower than that) point, the > BIOS is not able to address this via the physical address passed to it. Right, looks like efi_call_phys_prelog() needs rewriting to install a proper identity mapping that actually addresses *all* of available memory, instead of just the first PGDIR_SIZE bytes. -- 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
