From: Aaron Durbin Make ACPI be the default reset method for x86_64. If the reset mechanism fails using ACPI, it will default to using the keyboard controller. Signed-off-by: Aaron Durbin Cc: Len Brown Cc: Andi Kleen Signed-off-by: Andrew Morton --- Documentation/x86_64/boot-options.txt | 4 ++-- arch/x86_64/kernel/reboot.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff -puN Documentation/x86_64/boot-options.txt~x86_64-make-acpi-the-default-reset-option Documentation/x86_64/boot-options.txt --- a/Documentation/x86_64/boot-options.txt~x86_64-make-acpi-the-default-reset-option +++ a/Documentation/x86_64/boot-options.txt @@ -115,10 +115,10 @@ Rebooting warm Don't set the cold reboot flag cold Set the cold reboot flag triple Force a triple fault (init) - kbd Use the keyboard controller. cold reset (default) + kbd Use the keyboard controller. cold reset acpi Use the ACPI RESET_REG in the FADT. If ACPI is not configured or the ACPI reset does not work, the reboot path attempts the reset using - the keyboard controller. + the keyboard controller. (default) Using warm reset will be much faster especially on big memory systems because the BIOS will not go through the memory check. diff -puN arch/x86_64/kernel/reboot.c~x86_64-make-acpi-the-default-reset-option arch/x86_64/kernel/reboot.c --- a/arch/x86_64/kernel/reboot.c~x86_64-make-acpi-the-default-reset-option +++ a/arch/x86_64/kernel/reboot.c @@ -30,7 +30,7 @@ static enum { BOOT_TRIPLE = 't', BOOT_KBD = 'k', BOOT_ACPI = 'a' -} reboot_type = BOOT_KBD; +} reboot_type = BOOT_ACPI; static int reboot_mode = 0; int reboot_force; _