[PATCH] lockdep: x86 smp alternatives workaround

Disable SMP alternatives fixups (the patching in of NOPs on 1-CPU systems) if
the lock validator is enabled: there is a binutils section handling bug that
causes corrupted instructions when UP instructions are patched in.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Ingo Molnar 2006-07-03 00:24:57 -07:00 committed by Linus Torvalds
parent 2148270cd2
commit 3047e99ede

View file

@ -303,6 +303,16 @@ void alternatives_smp_switch(int smp)
struct smp_alt_module *mod;
unsigned long flags;
#ifdef CONFIG_LOCKDEP
/*
* A not yet fixed binutils section handling bug prevents
* alternatives-replacement from working reliably, so turn
* it off:
*/
printk("lockdep: not fixing up alternatives.\n");
return;
#endif
if (no_replacement || smp_alt_once)
return;
BUG_ON(!smp && (num_online_cpus() > 1));