diff options
authorMark Rutland <mark.rutland@arm.com>2014-10-23 16:33:33 +0100
committerKees Cook <keescook@google.com>2015-10-07 13:13:02 -0700
commitb11c7dd5bcf9ad2f7a49069e606333f1c42cad6a (patch)
parent7226149fe3fee527c7f3f43a75057c930745a022 (diff)
UPSTREAM: efi: efi-stub: notify on DTB absence
In the absence of a DTB configuration table, the EFI stub will happily continue attempting to boot a kernel, despite the fact that this kernel may not function without a description of the hardware. In this case, as with a typo'd "dtb=" option (e.g. "dbt=") or many other possible failures, the only output seen by the user will be the rather terse output from the EFI stub: EFI stub: Booting Linux Kernel... To aid those attempting to debug such failures, this patch adds a notice when no DTB is found, making the output more helpful: EFI stub: Booting Linux Kernel... EFI stub: Generating empty DTB Additionally, a positive acknowledgement is added when a user-specified DTB is in use: EFI stub: Booting Linux Kernel... EFI stub: Using DTB from command line Similarly, a positive acknowledgement is added when a DTB from a configuration table is in use: EFI stub: Booting Linux Kernel... EFI stub: Using DTB from configuration table Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Leif Lindholm <leif.lindholm@linaro.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Roy Franz <roy.franz@linaro.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> (cherry picked from commit 0bcaa9040d058684d58c36ef273b8946996c7078) Signed-off-by: Tomasz Figa <tfiga@chromium.org> Bug: 24475017 Change-Id: Ia2c69ebfa0f632c43ac014312c77dafccbe02305 Signed-off-by: Kees Cook <keescook@google.com>
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 75ee05964cbc..eb48a1a1a576 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -247,9 +247,18 @@ unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table,
goto fail_free_cmdline;
- if (!fdt_addr)
+ if (fdt_addr) {
+ pr_efi(sys_table, "Using DTB from command line\n");
+ } else {
/* Look for a device tree configuration table entry. */
fdt_addr = (uintptr_t)get_fdt(sys_table);
+ if (fdt_addr)
+ pr_efi(sys_table, "Using DTB from configuration table\n");
+ }
+ if (!fdt_addr)
+ pr_efi(sys_table, "Generating empty DTB\n");
status = handle_cmdline_files(sys_table, image, cmdline_ptr,
"initrd=", dram_base + SZ_512M,