@@ -9,6 +9,23 @@
#include <linux/efi.h>
#include <asm/efi.h>
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+ int block;
+
+ /* non-LPAE kernels can run anywhere */
+ if (!IS_ENABLED(CONFIG_ARM_LPAE))
+ return EFI_SUCCESS;
+
+ /* LPAE kernels need compatible hardware */
+ block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
+ if (block < 5) {
+ pr_efi_err(sys_table_arg, "This LPAE kernel is not supported by your CPU\n");
+ return EFI_UNSUPPORTED;
+ }
+ return EFI_SUCCESS;
+}
+
efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
unsigned long *image_addr,
unsigned long *image_size,
A kernel built with support for LPAE cannot boot to a state where it can inform the user about it if it fails due to missing LPAE support in the hardware. If we happen to be booting via UEFI, we can fail gracefully so check for LPAE support in the hardware on CONFIG_ARM_LPAE builds before entering the kernel proper. Suggested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- drivers/firmware/efi/libstub/arm32-stub.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) -- 2.5.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel