LoongArch: Fix built-in DTB detection

fdt_check_header(__dtb_start) will always success because kernel
provides a dummy dtb, and by coincidence __dtb_start clashed with
entry of this dummy dtb. The consequence is fdt passed from firmware
will never be taken.

Fix by trying to utilise __dtb_start only when CONFIG_BUILTIN_DTB is
enabled.

Cc: stable@vger.kernel.org
Fixes: 7b937cc243 ("of: Create of_root if no dtb provided by firmware")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
This commit is contained in:
Jiaxun Yang 2024-06-03 15:45:53 +08:00 committed by Huacai Chen
parent 6c3ca6654a
commit b56f67a6c7

View file

@ -282,7 +282,7 @@ static void __init fdt_setup(void)
return;
/* Prefer to use built-in dtb, checking its legality first. */
if (!fdt_check_header(__dtb_start))
if (IS_ENABLED(CONFIG_BUILTIN_DTB) && !fdt_check_header(__dtb_start))
fdt_pointer = __dtb_start;
else
fdt_pointer = efi_fdt_pointer(); /* Fallback to firmware dtb */