"tvec_bases too large for per-cpu data" commit broke early_serial_setup()

From: Eugene Surovegin
Date: Sat Apr 01 2006 - 15:54:37 EST


Hi!

Commit
a4a6198b80cf82eb8160603c98da218d1bd5e104
"[PATCH] tvec_bases too large for per-cpu data"

broke early_serial_setup() and maybe other code which uses
init_timer() before init_timers_cpu() is called.

This commit introduced run-time initialization dependence which never
existed before, namely, tvec_bases was always valid before this
change, but now it's a pointer which should be initialized prior to
use of any timer function.

If init_timer() is called before such initialization (in my case this
happens when PPC440GX board support code calls early_serial_setup to
register UARTs, serial8250_isa_init_ports() calls init_timer()),
"base" field in the timer_list struct is set to NULL.

When later mod_timer() is called for such timer it hangs in
lock_timer_base().

Rolling back this commit fixes the problem, although, this is
obviously not a proper fix.

I don't a fix I like, so I'll leave it to people more familiar with
this matter :)

--
Eugene



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