On Tue, May 21, 2019 at 12:33:24AM +0200, Mark Kettenis wrote:
> > Date: Sat, 18 May 2019 05:58:39 +0200 (CEST)
> > From: Mark Kettenis <[email protected]>
> >
> > > Date: Fri, 17 May 2019 17:56:52 -0400
> > > From: Patrick Wildt <[email protected]>
> > >
> > > Hi,
> > >
> > > claudio@ has a Kaby Lake that exceeds the 128 kB limit, being as big as
> > > 190 kB. So, for him the ucode isn't being loaded.
> > >
> > > On EFI systems we can simply ask EFI to allocate some memory for us.
> > > I'm not sure why this file is duplicated 4 times, but it looks like
> > > for efiboot this one is currently the file to patch.
> > >
> > > This diff works for claudio@'s EFI booted system. Since I don't know
> > > how much space is available on legacy systems I will not attempt to
> > > fix this for the legacy bootloader. Someone that knows more than me
> > > about x86 can attempt that.
> > >
> > > Feedback? ok?
> >
> > In principle, ye, that is the right approach.
> >
> > However, until Mike gets us to the point where we no longer care at
> > which physical address the kernel was loaded, efiboot will move the
> > kernel to a specific physical address after loading it and potentially
> > thrash all memory allocated through the EFI interfaces. So there is a
> > change that we will overwrite the microcode at that point.
> >
> > So it might actually be safer to just change the limit to 256k if
> > there is a good chance the the memory at the 1MB mark is unlikely to
> > be used by anything else.
>
> Actually, since we always move the kernel to 16MB, we can use
> AllocateMaxAddress to allocate a large enough block of memory below
> that. So the diff below should work (and does on my Skylake system
> that uses a 100k firmware).
>
> ok?
>
While I am frightened about gigantisch microcodes and EFI trying to fit things
into lowmem below the ISA hole, I suppose it knows what it's doing.
ok mlarkin, not sure how you want to integrate this into the MDS stuff
that is being worked on though. I'll take care of merging this into efi32/efi64
when I'm ready.
>
> Index: arch/amd64/stand/efiboot/exec_i386.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/stand/efiboot/exec_i386.c,v
> retrieving revision 1.1
> diff -u -p -r1.1 exec_i386.c
> --- arch/amd64/stand/efiboot/exec_i386.c 10 May 2019 21:20:42 -0000
> 1.1
> +++ arch/amd64/stand/efiboot/exec_i386.c 20 May 2019 22:25:38 -0000
> @@ -46,8 +46,13 @@
> #include "softraid_amd64.h"
> #endif
>
> +#include <efi.h>
> +#include <efiapi.h>
> +#include "eficall.h"
> #include "efiboot.h"
>
> +extern EFI_BOOT_SERVICES *BS;
> +
> typedef void (*startfuncp)(int, int, int, int, int, int, int, int)
> __attribute__ ((noreturn));
>
> @@ -165,6 +170,7 @@ run_loadfile(uint64_t *marks, int howto)
> void
> ucode_load(void)
> {
> + EFI_PHYSICAL_ADDRESS addr;
> uint32_t model, family, stepping;
> uint32_t dummy, signature;
> uint32_t vendor[4];
> @@ -200,12 +206,13 @@ ucode_load(void)
> return;
>
> buflen = sb.st_size;
> - if (buflen > 128*1024) {
> - printf("ucode too large\n");
> + addr = 16 * 1024 * 1024;
> + if (EFI_CALL(BS->AllocatePages, AllocateMaxAddress, EfiLoaderData,
> + EFI_SIZE_TO_PAGES(buflen), &addr) != EFI_SUCCESS) {
> + printf("cannot allocate memory for ucode\n");
> return;
> }
> -
> - buf = (char *)(1*1024*1024);
> + buf = (char *)((paddr_t)addr);
>
> if (read(fd, buf, buflen) != buflen) {
> close(fd);
>
>
