[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <1221908320-7183-1-git-send-email-righi.andrea@gmail.com>
Date: Sat, 20 Sep 2008 12:58:40 +0200
From: Andrea Righi <righi.andrea@...il.com>
To: robert.richter@....com, akpm@...ux-foundation.org
Cc: oprofile-list@...ts.sf.net, linux-kernel@...r.kernel.org
Subject: [PATCH -mm] oprofile: BUG: using smp_processor_id() in preemptible code
Add local_irq_save() / local_irq_restore() before setting per cpu variable
switch_index, to avoid the following BUG:
[ 449.166827] BUG: using smp_processor_id() in preemptible [00000000] code: modprobe/6998
[ 449.166848] caller is op_nmi_init+0xf0/0x2b0 [oprofile]
[ 449.166855] Pid: 6998, comm: modprobe Not tainted 2.6.27-rc5-mm1 #29
[ 449.166860] Call Trace:
[ 449.166872] [<ffffffff80362d67>] debug_smp_processor_id+0xd7/0xe0
[ 449.166887] [<ffffffffa00181c0>] op_nmi_init+0xf0/0x2b0 [oprofile]
[ 449.166902] [<ffffffffa0018000>] oprofile_init+0x0/0x60 [oprofile]
[ 449.166915] [<ffffffffa00180a9>] oprofile_arch_init+0x9/0x30 [oprofile]
[ 449.166928] [<ffffffffa001801e>] oprofile_init+0x1e/0x60 [oprofile]
[ 449.166937] [<ffffffff8020903b>] _stext+0x3b/0x160
[ 449.166946] [<ffffffff80477985>] __mutex_unlock_slowpath+0xe5/0x190
[ 449.166955] [<ffffffff80262c1a>] trace_hardirqs_on_caller+0xca/0x140
[ 449.166965] [<ffffffff8026f7fc>] sys_init_module+0xdc/0x210
[ 449.166972] [<ffffffff8020b7cb>] system_call_fastpath+0x16/0x1b
Signed-off-by: Andrea Righi <righi.andrea@...il.com>
---
arch/x86/oprofile/nmi_int.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c
index d4c2f2d..2e63357 100644
--- a/arch/x86/oprofile/nmi_int.c
+++ b/arch/x86/oprofile/nmi_int.c
@@ -520,6 +520,7 @@ int __init op_nmi_init(struct oprofile_operations *ops)
__u8 vendor = boot_cpu_data.x86_vendor;
__u8 family = boot_cpu_data.x86;
char *cpu_type;
+ unsigned long flags;
int ret = 0;
if (!cpu_has_apic)
@@ -580,7 +581,9 @@ int __init op_nmi_init(struct oprofile_operations *ops)
register_cpu_notifier(&oprofile_cpu_nb);
#endif
/* default values, can be overwritten by model */
+ local_irq_save(flags);
__get_cpu_var(switch_index) = 0;
+ local_irq_restore(flags);
ops->create_files = nmi_create_files;
ops->setup = nmi_setup;
ops->shutdown = nmi_shutdown;
--
1.5.4.3
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists