linux/arch/frv
Peter Zijlstra aa02cd2d9b xtime_lock vs update_process_times
Commit d3d74453c3 ("hrtimer: fixup the
HRTIMER_CB_IRQSAFE_NO_SOFTIRQ fallback") broke several archs, and since
only Russell bothered to merge the fix, and Greg to ACK his arch, I'm
sending this for merger.

I have confirmation that the Alpha bit results in a booting kernel.
That leaves: blackfin, frv, sh and sparc untested.

The deadlock in question was found by Russell:

  IRQ handle
    -> timer_tick() - xtime seqlock held for write
      -> update_process_times()
        -> run_local_timers()
          -> hrtimer_run_queues()
            -> hrtimer_get_softirq_time() - tries to get a read lock

Now, Thomas assures me the fix is trivial, only do_timer() needs to be
done under the xtime_lock, and update_process_times() can savely be
removed from under it.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Greg Ungerer <gerg@uclinux.org>
CC: Richard Henderson <rth@twiddle.net>
CC: Bryan Wu <bryan.wu@analog.com>
CC: David Howells <dhowells@redhat.com>
CC: Paul Mundt <lethal@linux-sh.org>
CC: William Irwin <wli@holomorphy.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-13 13:29:25 -08:00
..
boot FRV: Drop 'TOPDIR' from Makefiles 2008-01-28 23:14:37 +01:00
kernel xtime_lock vs update_process_times 2008-02-13 13:29:25 -08:00
lib move frv docs one level up 2008-02-03 15:54:28 +02:00
mb93090-mb00 scatterlist fallout: frv 2007-10-27 22:18:11 -07:00
mm CONFIG_HIGHPTE vs. sub-page page tables. 2008-02-08 09:22:42 -08:00
Kconfig ide: introduce HAVE_IDE 2008-02-09 10:46:40 +01:00
Kconfig.debug [PATCH] frv: drop unsupported debugging features 2006-01-08 20:13:36 -08:00
Makefile kbuild: enable 'make AFLAGS=...' to add additional options to AS 2007-10-15 21:59:31 +02:00
defconfig [PATCH] FRV: Add defconfig 2005-07-07 18:23:42 -07:00