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/sound/oss/os.h

#define ALLOW_SELECT
#undef NO_INLINE_ASM
#define SHORT_BANNERS
#define MANUAL_PNP
#undef  DO_TIMINGS

#include <linux/module.h>

#ifdef __KERNEL__
#include <linux/string.h>
#include <linux/fs.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/param.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <asm/page.h>
#include <linux/vmalloc.h>
#include <linux/uaccess.h>
#include <linux/poll.h>
#include <linux/pci.h>
#endif

#include <linux/soundcard.h>

#define FALSE	0
#define TRUE	1

extern int sound_alloc_dma(int chn, char *deviceID);
extern int sound_open_dma(int chn, char *deviceID);
extern void sound_free_dma(int chn);
extern void sound_close_dma(int chn);

extern void reprogram_timer(void);

#define USE_AUTOINIT_DMA

extern void *sound_mem_blocks[1024];
extern int sound_nblocks;

#undef PSEUDO_DMA_AUTOINIT
#define ALLOW_BUFFER_MAPPING

extern const struct file_operations oss_sound_fops;