x86/mce: Make timer handling more robust

Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.

Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.

Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.

Reported-by: Erik Veijola <erik.veijola@intel.com>
Tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

path: root/include/dt-bindings/clock/clps711x-clock.h

/*
 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#ifndef __DT_BINDINGS_CLOCK_CLPS711X_H
#define __DT_BINDINGS_CLOCK_CLPS711X_H

#define CLPS711X_CLK_DUMMY	0
#define CLPS711X_CLK_CPU	1
#define CLPS711X_CLK_BUS	2
#define CLPS711X_CLK_PLL	3
#define CLPS711X_CLK_TIMERREF	4
#define CLPS711X_CLK_TIMER1	5
#define CLPS711X_CLK_TIMER2	6
#define CLPS711X_CLK_PWM	7
#define CLPS711X_CLK_SPIREF	8
#define CLPS711X_CLK_SPI	9
#define CLPS711X_CLK_UART	10
#define CLPS711X_CLK_TICK	11
#define CLPS711X_CLK_MAX	12

#endif