From: Ard Biesheuvel <ardb@xxxxxxxxxx>
Now that the x86 EFI stub calls into some APIs exposed by the
decompressor (e.g., kaslr_get_random_long()), it is necessary to ensure
that the global boot_params variable is set correctly before doing so.
Note that the decompressor and the kernel proper carry conflicting
declarations for the global variable 'boot_params' so refer to it via an
alias to work around this.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/firmware/efi/libstub/x86-stub.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index 3bfc59637dd1..51407207ded5 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -812,12 +812,15 @@ void __noreturn efi_stub_entry(efi_handle_t handle,
efi_system_table_t *sys_table_arg,
struct boot_params *boot_params)
{
+ extern struct boot_params *bpp asm("boot_params");
efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID;
struct setup_header *hdr = &boot_params->hdr;
const struct linux_efi_initrd *initrd = NULL;
unsigned long kernel_entry;
efi_status_t status;
+ bpp = boot_params;
+
efi_system_table = sys_table_arg;
/* Check if we were booted by the EFI firmware */
if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
--
2.42.0.655.g421f12c284-goog
