• Huacai Chen's avatar
    PM / reboot: call syscore_shutdown() after disable_nonboot_cpus() · 6f389a8f
    Huacai Chen authored
    As commit 40dc166c (PM / Core: Introduce struct syscore_ops for core
    subsystems PM) say, syscore_ops operations should be carried with one
    CPU on-line and interrupts disabled. However, after commit f96972f2
    (kernel/sys.c: call disable_nonboot_cpus() in kernel_restart()),
    syscore_shutdown() is called before disable_nonboot_cpus(), so break
    the rules. We have a MIPS machine with a 8259A PIC, and there is an
    external timer (HPET) linked at 8259A. Since 8259A has been shutdown
    too early (by syscore_shutdown()), disable_nonboot_cpus() runs without
    timer interrupt, so it hangs and reboot fails. This patch call
    syscore_shutdown() a little later (after disable_nonboot_cpus()) to
    avoid reboot failure, this is the same way as poweroff does.
    
    For consistency, add disable_nonboot_cpus() to kernel_halt().
    Signed-off-by: default avatarHuacai Chen <chenhc@lemote.com>
    Cc: <stable@vger.kernel.org>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    6f389a8f