The logic in efi_random_alloc() will iterate over the memory map twice,
once to count the number of candidate slots, and another time to locate
the chosen slot after randomization.

If there is insufficient memory to do the allocation, the second loop
will run to completion without actually having located a slot, but we
currently return EFI_SUCCESS in this case, as we fail to initialize
status to the appropriate error value of EFI_OUT_OF_RESOURCES.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

In some cases, we expose the kernel's struct screen_info to the EFI stub
directly, so it gets populated before even entering the kernel.  This
means the early console is available as soon as the early param parsing
happens, which is nice. It also means we need two different ways to pass
this information, as this trick only works if the EFI stub is baked into
the core kernel image, which is not always the case.

Huacai reports that the preparatory refactoring that was needed to
implement this alternative method for zboot resulted in a non-functional
efifb earlycon for other cases as well, due to the reordering of the
kernel image relocation with the population of the screen_info struct,
and the latter now takes place after copying the image to its new
location, which means we copy the old, uninitialized state.

So let's ensure that the same-image version of alloc_screen_info()
produces the correct screen_info pointer, by taking the displacement of
the loaded image into account.

Reported-by: Huacai Chen <chenhuacai@loongson.cn>
Tested-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/linux-efi/20230310021749.921041-1-chenhuacai@loongson.cn/
Fixes: 42c8ea3dca094ab8 ("efi: libstub: Factor out EFI stub entrypoint into separate file")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Avoid needlessly rebuilding the compressed image by adding the file
'vmlinuz' to the 'targets' Kbuild make variable.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Another Lenovo convertable which reports a landscape resolution of
1920x1200 with a pitch of (1920 * 4) bytes, while the actual framebuffer
has a resolution of 1200x1920 with a pitch of (1200 * 4) bytes.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Commit 8633ef82f101 ("drivers/firmware: consolidate EFI framebuffer setup
for all arches") moved the sysfb_apply_efi_quirks() call in sysfb_init()
from before the [sysfb_]parse_mode() call to after it.
But sysfb_apply_efi_quirks() modifies the global screen_info struct which
[sysfb_]parse_mode() parses, so doing it later is too late.

This has broken all DMI based quirks for correcting wrong firmware efifb
settings when simpledrm is used.

To fix this move the sysfb_apply_efi_quirks() call back to its old place
and split the new setup of the efifb_fwnode (which requires
the platform_device) into its own function and call that at
the place of the moved sysfb_apply_efi_quirks(pd) calls.

Fixes: 8633ef82f101 ("drivers/firmware: consolidate EFI framebuffer setup for all arches")
Cc: stable@vger.kernel.org
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

We no longer use the recsize argument for locating the string table in
an SMBIOS record, so we can drop it from the internal API.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Instead of using the SMBIOS type 1 record 'family' field, which is often
modified by OEMs, use the type 4 'processor ID' and 'processor version'
fields, which are set to a small set of probe-able values on all known
Ampere EFI systems in the field.

Fixes: 550b33cfd4452968 ("arm64: efi: Force the use of ...")
Tested-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

The type 1 SMBIOS record happens to always be the same size, but there
are other record types which have been augmented over time, and so we
should really use the length field in the header to decide where the
string table starts.

Fixes: 550b33cfd4452968 ("arm64: efi: Force the use of ...")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

Commit 732ea9db9d8a ("efi: libstub: Move screen_info handling to common
code") reorganized the earlycon handling so that all architectures pass
the screen_info data via a EFI config table instead of populating struct
screen_info directly, as the latter is only possible when the EFI stub
is baked into the kernel (and not into the decompressor).

However, this means that struct screen_info may not have been populated
yet by the time the earlycon probe takes place, and this results in a
non-functional early console.

So let's probe again right after parsing the config tables and
populating struct screen_info. Note that this means that earlycon output
starts a bit later than before, and so it may fail to capture issues
that occur while doing the early EFI initialization.

Fixes: 732ea9db9d8a ("efi: libstub: Move screen_info handling to common code")
Reported-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

After relocating the executable image, use the EFI memory attributes
protocol to remap the code and data regions with the appropriate
permissions.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>