tree e84f2647dc2ae71f2e54f2256ebce87624c11d97
parent 493f3358cb289ccf716c5a14fa5bb52ab75943e5
author Thomas Gleixner <tglx@linutronix.de> 1298669663 +0100
committer Thomas Gleixner <tglx@linutronix.de> 1298709928 +0100

clockevents: Prevent oneshot mode when broadcast device is periodic

When the per cpu timer is marked CLOCK_EVT_FEAT_C3STOP, then we only
can switch into oneshot mode, when the backup broadcast device
supports oneshot mode as well. Otherwise we would try to switch the
broadcast device into an unsupported mode unconditionally. This went
unnoticed so far as the current available broadcast devices support
oneshot mode. Seth unearthed this problem while debugging and working
around an hpet related BIOS wreckage.

Add the necessary check to tick_is_oneshot_available().

Reported-and-tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <alpine.LFD.2.00.1102252231200.2701@localhost6.localdomain6>
Cc: stable@kernel.org # .21 ->