From ac818314499b707a97690d5ee835e6ba40a407c1 Mon Sep 17 00:00:00 2001
From: Neil Brown <neilb@suse.de>
Date: Wed, 24 Nov 2010 11:28:01 +1100
Subject: [CPUFREQ] Missing "unregister_cpu_notifier" in powernow-k8.c
It appears that when powernow-k8 finds that
No compatible ACPI _PSS objects found.
and suggests
Try again with latest BIOS.
it fails the module load, but does not unregister the cpu_notifier that was
registered in powernowk8_init
This ends up leaving freed memory on the cpu notifier list for some other
poor module (e.g. md/raid5) to come along and trip over.
The following might be a partial fix, but I suspect there is probably other
clean-up that is needed.
( https://bugzilla.novell.com/show_bug.cgi?id=655215 has full dmesg traces).
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
---
arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index 35c7e65..302963f 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -1537,6 +1537,7 @@ static struct notifier_block cpb_nb = {
static int __cpuinit powernowk8_init(void)
{
unsigned int i, supported_cpus = 0, cpu;
+ int rv;
for_each_online_cpu(i) {
int rc;
@@ -1574,7 +1575,13 @@ static int __cpuinit powernowk8_init(void)
(cpb_enabled ? "on" : "off"));
}
- return cpufreq_register_driver(&cpufreq_amd64_driver);
+ rv = cpufreq_register_driver(&cpufreq_amd64_driver);
+ if (rv < 0 && boot_cpu_has(X86_FEATURE_CPB)) {
+ unregister_cpu_notifier(&cpb_nb);
+ msrs_free(msrs);
+ msrs = NULL;
+ }
+ return rv;
}
/* driver entry point for term */
--
cgit v1.1
From a536b126f211bdf9a0eecce0d403a26900d2106c Mon Sep 17 00:00:00 2001
From: Dave Jones <davej@redhat.com>
Date: Tue, 23 Nov 2010 21:29:31 -0500
Subject: [CPUFREQ] Fix another notifier leak in powernow-k8.
Do the notifier registration later, so we don't have to worry
about freeing it if we fail the msr allocation.
Signed-off-by: Dave Jones <davej@redhat.com>
---
arch/x86/kernel/cpu/cpufreq/powernow-k8.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
index 302963f..c567dec 100644
--- a/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
+++ b/arch/x86/kernel/cpu/cpufreq/powernow-k8.c
@@ -1556,14 +1556,14 @@ static int __cpuinit powernowk8_init(void)
cpb_capable = true;
- register_cpu_notifier(&cpb_nb);
-
msrs = msrs_alloc();
if (!msrs) {
printk(KERN_ERR "%s: Error allocating msrs!\n", __func__);
return -ENOMEM;
}
+ register_cpu_notifier(&cpb_nb);
+
rdmsr_on_cpus(cpu_online_mask, MSR_K7_HWCR, msrs);
for_each_cpu(cpu, cpu_online_mask) {
--
cgit v1.1
From 8f5bc2abfd4240b1f55425a3d36b6e6c391bc148 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Tue, 1 Mar 2011 17:41:10 +0100
Subject: [CPUFREQ] fix BUG on cpufreq policy init failure
cpufreq_register_driver sets cpufreq_driver to a structure owned (and
placed) in the caller's memory. If cpufreq policy fails in its ->init
function, sysdev_driver_register returns nonzero in
cpufreq_register_driver. Now, cpufreq_register_driver returns an error
without setting cpufreq_driver back to NULL.
Usually cpufreq policy modules are unloaded because they propagate the
error to the module init function and return that.
So a later access to any member of cpufreq_driver causes bugs like:
BUG: unable to handle kernel paging request at ffffffffa00270a0
IP: [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0
PGD 1805067 PUD 1809063 PMD 1c3f90067 PTE 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/virtual/net/tun0/statistics/collisions
CPU 0
Modules linked in: ...
Pid: 5677, comm: thunderbird-bin Tainted: G W 2.6.38-rc4-mm1_64+ #1389 To be filled by O.E.M./To Be Filled By O.E.M.
RIP: 0010:[<ffffffff8145eca3>] [<ffffffff8145eca3>] cpufreq_cpu_get+0x53/0xe0
RSP: 0018:ffff8801aec37d98 EFLAGS: 00010086
RAX: 0000000000000202 RBX: 0000000000000000 RCX: 0000000000000001
RDX: ffffffffa00270a0 RSI: 0000000000001000 RDI: ffffffff8199ece8
...
Call Trace:
[<ffffffff8145f490>] cpufreq_quick_get+0x10/0x30
[<ffffffff8103f12b>] show_cpuinfo+0x2ab/0x300
[<ffffffff81136292>] seq_read+0xf2/0x3f0
[<ffffffff8126c5d3>] ? __strncpy_from_user+0x33/0x60
[<ffffffff8116850d>] proc_reg_read+0x6d/0xa0
[<ffffffff81116e53>] vfs_read+0xc3/0x180
[<ffffffff81116f5c>] sys_read+0x4c/0x90
[<ffffffff81030dbb>] system_call_fastpath+0x16/0x1b
...
It's all cause by weird fail path handling in cpufreq_register_driver.
To fix that, shuffle the code to do proper handling with gotos.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Dave Jones <davej@redhat.com>
---
drivers/cpufreq/cpufreq.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 1109f68..5cb4d09 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1919,8 +1919,10 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
ret = sysdev_driver_register(&cpu_sysdev_class,
&cpufreq_sysdev_driver);
+ if (ret)
+ goto err_null_driver;
- if ((!ret) && !(cpufreq_driver->flags & CPUFREQ_STICKY)) {
+ if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) {
int i;
ret = -ENODEV;
@@ -1935,21 +1937,22 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
if (ret) {
dprintk("no CPU initialized for driver %s\n",
driver_data->name);
- sysdev_driver_unregister(&cpu_sysdev_class,
- &cpufreq_sysdev_driver);
-
- spin_lock_irqsave(&cpufreq_driver_lock, flags);
- cpufreq_driver = NULL;
- spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ goto err_sysdev_unreg;
}
}
- if (!ret) {
- register_hotcpu_notifier(&cpufreq_cpu_notifier);
- dprintk("driver %s up and running\n", driver_data->name);
- cpufreq_debug_enable_ratelimit();
- }
+ register_hotcpu_notifier(&cpufreq_cpu_notifier);
+ dprintk("driver %s up and running\n", driver_data->name);
+ cpufreq_debug_enable_ratelimit();
+ return 0;
+err_sysdev_unreg:
+ sysdev_driver_unregister(&cpu_sysdev_class,
+ &cpufreq_sysdev_driver);
+err_null_driver:
+ spin_lock_irqsave(&cpufreq_driver_lock, flags);
+ cpufreq_driver = NULL;
+ spin_unlock_irqrestore(&cpufreq_driver_lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_register_driver);
--
cgit v1.1
From 853cee26e2a0c5f97386beca4c67b11c3cd85b8e Mon Sep 17 00:00:00 2001
From: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
Date: Tue, 15 Feb 2011 17:44:11 +0000
Subject: [CPUFREQ] p4-clockmod: print EST-capable warning message only once
Print the message only once. I see it 16 times on a 2P box with 16 logical CPUs.
Signed-off-by: Naga Chumbalkar <nagananda.chumbalkar@hp.com>
---
arch/x86/kernel/cpu/cpufreq/p4-clockmod.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/cpu/cpufreq/p4-clockmod.c b/arch/x86/kernel/cpu/cpufreq/p4-clockmod.c
index bd1cac7..52c9364 100644
--- a/arch/x86/kernel/cpu/cpufreq/p4-clockmod.c
+++ b/arch/x86/kernel/cpu/cpufreq/p4-clockmod.c
@@ -158,9 +158,9 @@ static unsigned int cpufreq_p4_get_frequency(struct cpuinfo_x86 *c)
{
if (c->x86 == 0x06) {
if (cpu_has(c, X86_FEATURE_EST))
- printk(KERN_WARNING PFX "Warning: EST-capable CPU "
- "detected. The acpi-cpufreq module offers "
- "voltage scaling in addition of frequency "
+ printk_once(KERN_WARNING PFX "Warning: EST-capable "
+ "CPU detected. The acpi-cpufreq module offers "
+ "voltage scaling in addition to frequency "
"scaling. You should use that instead of "
"p4-clockmod, if possible.\n");
switch (c->x86_model) {
--
cgit v1.1