ACPI: reboot: Avoid racing after writing to ACPI RESET_REG
authorZhang Rui <rui.zhang@intel.com>
Tue, 13 Oct 2020 07:35:57 +0000 (15:35 +0800)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 16 Oct 2020 16:04:52 +0000 (18:04 +0200)
commit9a4888888cc09b0ff3d0a1dd32df88742d29a293
tree996376bd71c8900dd92afe2b656dae284ac609ee
parentcf1d2b44f6c701ffff58606b5b8a8996190d6e7d
ACPI: reboot: Avoid racing after writing to ACPI RESET_REG

According to the ACPI spec, "The system must reset immediately following
the write to the ACPI RESET_REG register.", but there are cases that the
system does not follow this and results in racing with the subsequetial
reboot mechanism, which brings unexpected behavior.

Fix this by adding a 15ms delay after writing to the ACPI RESET_REG.

Reported-by: Ghorai, Sukumar <sukumar.ghorai@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[ rjw: Edit comment in the code and subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
drivers/acpi/reboot.c