On Sun, 25 Oct 2020 at 17:19, Arvind Sankar <nivedita@xxxxxxxxxxxx> wrote:
>
> On Sun, Oct 11, 2020 at 10:20:12AM -0400, Arvind Sankar wrote:
> > The image_size argument to efi_relocate_kernel() is currently specified
> > as init_size, but this is unnecessarily large. The compressed kernel is
> > much smaller, in fact, its image only extends up to the start of _bss,
> > since at this point, the .bss section is still uninitialized.
> >
> > Depending on compression level, this can reduce the amount of data
> > copied by 4-5x.
> >
> > Signed-off-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>
>
> Ping
>
I'll pick this up as a fix once the merge window closes.
> > ---
> > drivers/firmware/efi/libstub/x86-stub.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
> > index 3672539cb96e..f14c4ff5839f 100644
> > --- a/drivers/firmware/efi/libstub/x86-stub.c
> > +++ b/drivers/firmware/efi/libstub/x86-stub.c
> > @@ -715,8 +715,11 @@ unsigned long efi_main(efi_handle_t handle,
> > (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE) ||
> > (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) ||
> > (image_offset == 0)) {
> > + extern char _bss[];
> > +
> > status = efi_relocate_kernel(&bzimage_addr,
> > - hdr->init_size, hdr->init_size,
> > + (unsigned long)_bss - bzimage_addr,
> > + hdr->init_size,
> > hdr->pref_address,
> > hdr->kernel_alignment,
> > LOAD_PHYSICAL_ADDR);
> > --
> > 2.26.2
> >
