Ben Hutchings wrote: > On Thu, 2009-06-18 at 16:34 -0600, Chris Friesen wrote:
> Having investigated further, I believe it has been safe since this > change made in 2.6.27 (which cleverly preempted the new year): > > commit b845b517b5e3706a3729f6ea83b88ab85f0725b0 > Author: Peter Zijlstra <[email protected]> > Date: Fri Aug 8 21:47:09 2008 +0200 > > printk: robustify printk > > Avoid deadlocks against rq->lock and xtime_lock by deferring the klogd > wakeup by polling from the timer tick. > > Signed-off-by: Peter Zijlstra <[email protected]> > Signed-off-by: Ingo Molnar <[email protected]> > >> In addition, is it allowed for older kernels also or is Chris Adams' >> patch something that should get picked up for the 2.6.27 stable series? > > Anything older than 2.6.27 appears to need a change along the lines of > the above-mentioned commit or Chris's patch. Note that this was not the > only case where printk() could be called under xtime_lock. For example, > in arch/alpha/kernel/time.c timer_interrupt() calls set_rtc_mmss() which > can call printk(). It appears that the patch in question went into mainline in 2.6.28-rc1 after being developed on the -tip tree. So it doesn't appear to be present in the mainline 2.6.27 kernel. Chris -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
