lkml.org 
[lkml]   [2006]   [May]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 31/61] lock validator: SMP alternatives workaround
From: Ingo Molnar <mingo@elte.hu>

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>
---
arch/i386/kernel/alternative.c | 10 ++++++++++
1 file changed, 10 insertions(+)

Index: linux/arch/i386/kernel/alternative.c
===================================================================
--- linux.orig/arch/i386/kernel/alternative.c
+++ linux/arch/i386/kernel/alternative.c
@@ -301,6 +301,16 @@ 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));
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2006-05-29 23:41    [W:0.654 / U:3.144 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site