Commit Graph

4 Commits

Author SHA1 Message Date
Rusty Russell
fcc5c4a2fe x86: avoid theoretical spurious NMI backtraces with CONFIG_CPUMASK_OFFSTACK=y
In theory (though not shown in practice) alloc_cpumask_var() doesn't zero
memory, so CPUs might print an "NMI backtrace for cpu %d" once on boot.

(Bug introduced in fcef8576d8).

[ Impact: avoid theoretical syslog noise in rare configs ]

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <alpine.DEB.2.00.0904202113520.10097@gandalf.stny.rr.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-21 10:09:50 +02:00
Rusty Russell
2f537a9f8e x86: fix boot crash in NMI watchdog with CONFIG_CPUMASK_OFFSTACK=y and flat APIC
fcef8576d8 converted backtrace_mask to a
cpumask_var_t, and assumed check_nmi_watchdog was called before
nmi_watchdog_tick was ever called.  Steven's oops shows I was wrong.

This is something of a bandaid: I'm not sure we *should* be calling
nmi_watchdog_tick before check_nmi_watchdog.  Note that gcc eliminates
this test for the CONFIG_CPUMASK_OFFSTACK=n case.

[ Impact: fix boot crash in rare configs ]

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
LKML-Reference: <alpine.DEB.2.00.0904202113520.10097@gandalf.stny.rr.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-21 10:09:49 +02:00
Rusty Russell
fcef8576d8 cpumask: convert arch/x86/kernel/nmi.c's backtrace_mask to a cpumask_var_t
Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

I *think* every path calls check_nmi_watchdog before using the
watchdog, so that's the right place for the initialization.

If that's wrong, we'll get a nice NULL-deref with
CONFIG_CPUMASK_OFFSTACK=y, and have uncovered another bug.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-13 14:49:49 +10:30
Ingo Molnar
f62bae5009 x86, apic: move APIC drivers to arch/x86/kernel/apic/*
arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.

Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-02-17 18:17:36 +01:00