Re: [PATCH] x86: fix cpu-hotplug regression
On Fri, Nov 09, 2007 at 12:16:34PM -0800, Andrew Morton wrote:
> On Wed, 7 Nov 2007 23:15:38 +0900
> "Akinobu Mita" <[EMAIL PROTECTED]> wrote:
>
> > > [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
> > > CPU_UP_PREPARE)
> > >
> > > Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
> > > ("cpu hotplug: mce: fix cpu hotplug error handling").
> > >
> > > For CPUs not brought up during boot (using maxcpus and additional_cpus
> > > parameters) we don't know whether mce is supported or not at
> > > "CPU_UP_PREPARE"-time.
> > > Thus mce_cpu_callback should be called after the CPU is online.
> >
> > Thank you for finding and fixing the problem.
> > I added two fixes to your patch:
> >
> > - Avoid mce_remove_device() for the CPU that is not correctly initialized
> > by mce_create_device() failure.
> >
> > - make CPU_ONLINE callback always return NOTIFY_OK.
> > Because CPU_ONLINE callback return value is always ignored.
> >
> > > Signed-off-by: Andreas Herrmann <[EMAIL PROTECTED]>
> >
> > [EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK]
> > [EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device]
> >
> > Signed-off-by: Akinobu Mita <[EMAIL PROTECTED]>
>
> Andreas, could you please review and preferably runtime-test this new
> version?
I'll test it today ...
> Assuming that all goes well could one of you please prepare a final patch
> with a complete changelog?
... and can send a final patch after successful testing.
Regards,
Andreas
--
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Re: [PATCH] x86: fix cpu-hotplug regression
On Fri, Nov 09, 2007 at 12:16:34PM -0800, Andrew Morton wrote: On Wed, 7 Nov 2007 23:15:38 +0900 Akinobu Mita [EMAIL PROTECTED] wrote: [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on CPU_UP_PREPARE) Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc (cpu hotplug: mce: fix cpu hotplug error handling). For CPUs not brought up during boot (using maxcpus and additional_cpus parameters) we don't know whether mce is supported or not at CPU_UP_PREPARE-time. Thus mce_cpu_callback should be called after the CPU is online. Thank you for finding and fixing the problem. I added two fixes to your patch: - Avoid mce_remove_device() for the CPU that is not correctly initialized by mce_create_device() failure. - make CPU_ONLINE callback always return NOTIFY_OK. Because CPU_ONLINE callback return value is always ignored. Signed-off-by: Andreas Herrmann [EMAIL PROTECTED] [EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK] [EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device] Signed-off-by: Akinobu Mita [EMAIL PROTECTED] Andreas, could you please review and preferably runtime-test this new version? I'll test it today ... Assuming that all goes well could one of you please prepare a final patch with a complete changelog? ... and can send a final patch after successful testing. Regards, Andreas -- Operating | AMD Saxony Limited Liability Company Co. KG, System | Wilschdorfer Landstr. 101, 01109 Dresden, Germany Research | Register Court Dresden: HRA 4896, General Partner authorized Center | to represent: AMD Saxony LLC (Wilmington, Delaware, US) (OSRC) | General Manager of AMD Saxony LLC: Dr. Hans-R. Deppe, Thomas McCoy - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86: fix cpu-hotplug regression
On Wed, 7 Nov 2007 23:15:38 +0900
"Akinobu Mita" <[EMAIL PROTECTED]> wrote:
> > [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
> > CPU_UP_PREPARE)
> >
> > Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
> > ("cpu hotplug: mce: fix cpu hotplug error handling").
> >
> > For CPUs not brought up during boot (using maxcpus and additional_cpus
> > parameters) we don't know whether mce is supported or not at
> > "CPU_UP_PREPARE"-time.
> > Thus mce_cpu_callback should be called after the CPU is online.
>
> Thank you for finding and fixing the problem.
> I added two fixes to your patch:
>
> - Avoid mce_remove_device() for the CPU that is not correctly initialized
> by mce_create_device() failure.
>
> - make CPU_ONLINE callback always return NOTIFY_OK.
> Because CPU_ONLINE callback return value is always ignored.
>
> > Signed-off-by: Andreas Herrmann <[EMAIL PROTECTED]>
>
> [EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK]
> [EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device]
>
> Signed-off-by: Akinobu Mita <[EMAIL PROTECTED]>
Andreas, could you please review and preferably runtime-test this new
version?
Assuming that all goes well could one of you please prepare a final patch
with a complete changelog?
Thanks.
-
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Re: [PATCH] x86: fix cpu-hotplug regression
On Wed, 7 Nov 2007 23:15:38 +0900 Akinobu Mita [EMAIL PROTECTED] wrote: [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on CPU_UP_PREPARE) Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc (cpu hotplug: mce: fix cpu hotplug error handling). For CPUs not brought up during boot (using maxcpus and additional_cpus parameters) we don't know whether mce is supported or not at CPU_UP_PREPARE-time. Thus mce_cpu_callback should be called after the CPU is online. Thank you for finding and fixing the problem. I added two fixes to your patch: - Avoid mce_remove_device() for the CPU that is not correctly initialized by mce_create_device() failure. - make CPU_ONLINE callback always return NOTIFY_OK. Because CPU_ONLINE callback return value is always ignored. Signed-off-by: Andreas Herrmann [EMAIL PROTECTED] [EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK] [EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device] Signed-off-by: Akinobu Mita [EMAIL PROTECTED] Andreas, could you please review and preferably runtime-test this new version? Assuming that all goes well could one of you please prepare a final patch with a complete changelog? Thanks. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86: fix cpu-hotplug regression
> [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
> CPU_UP_PREPARE)
>
> Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
> ("cpu hotplug: mce: fix cpu hotplug error handling").
>
> For CPUs not brought up during boot (using maxcpus and additional_cpus
> parameters) we don't know whether mce is supported or not at
> "CPU_UP_PREPARE"-time.
> Thus mce_cpu_callback should be called after the CPU is online.
Thank you for finding and fixing the problem.
I added two fixes to your patch:
- Avoid mce_remove_device() for the CPU that is not correctly initialized
by mce_create_device() failure.
- make CPU_ONLINE callback always return NOTIFY_OK.
Because CPU_ONLINE callback return value is always ignored.
> Signed-off-by: Andreas Herrmann <[EMAIL PROTECTED]>
[EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK]
[EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device]
Signed-off-by: Akinobu Mita <[EMAIL PROTECTED]>
---
arch/x86/kernel/cpu/mcheck/mce_64.c | 18 +++---
1 file changed, 11 insertions(+), 7 deletions(-)
Index: 2.6-git/arch/x86/kernel/cpu/mcheck/mce_64.c
===
--- 2.6-git.orig/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ 2.6-git/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -802,6 +802,8 @@ static struct sysdev_attribute *mce_attr
NULL
};
+static cpumask_t mce_device_initialized = CPU_MASK_NONE;
+
/* Per cpu sysdev init. All of the cpus still share the same ctl bank */
static __cpuinit int mce_create_device(unsigned int cpu)
{
@@ -825,6 +827,7 @@ static __cpuinit int mce_create_device(u
if (err)
goto error;
}
+ cpu_set(cpu, mce_device_initialized);
return 0;
error:
@@ -841,10 +844,14 @@ static void mce_remove_device(unsigned i
{
int i;
+ if (!cpu_isset(cpu, mce_device_initialized))
+ return;
+
for (i = 0; mce_attributes[i]; i++)
sysdev_remove_file(_cpu(device_mce,cpu),
mce_attributes[i]);
sysdev_unregister(_cpu(device_mce,cpu));
+ cpu_clear(cpu, mce_device_initialized);
}
/* Get notified when a cpu comes on/off. Be hotplug friendly. */
@@ -852,21 +859,18 @@ static int
mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
- int err = 0;
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- err = mce_create_device(cpu);
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ mce_create_device(cpu);
break;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
mce_remove_device(cpu);
break;
}
- return err ? NOTIFY_BAD : NOTIFY_OK;
+ return NOTIFY_OK;
}
static struct notifier_block mce_cpu_notifier = {
-
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Re: [PATCH] x86: fix cpu-hotplug regression
On Wed, Nov 07, 2007 at 03:35:43AM +0100, Andi Kleen wrote:
> On Wednesday 07 November 2007 02:12, Andreas Herrmann wrote:
>
> > In cases where not all CPUs are brought up during
> > boot (e.g. using maxcpus and additional_cpus parameters)
> > mce_cpu_callback now returns NOTFIY_BAD because
> > for such CPUs cpu_data is not completely filled when
> > the notifier is called. Thus mce_create_device fails right
> > at its beginning:
> >
> > if (!mce_available(_data[cpu]))
> > return -EIO;
> >
> > As a quick fix I suggest to check boot_cpu_data for MCE.
>
> I guess it would be better to just move the device creation
> to after the CPU has booted. AKA call mce_create_dev() on CPU_ONLINE
> instead.
Yes, and this was the old behaviour. The mentioned patch changed it -
("do mce_create_device in CPU_UP_PREPARE instead of CPU_ONLINE").
Thinking twice about the problem it seems obvious that this part
of the patch should just be reverted.
Attached is a new fix (diff against 2.6.24-rc2).
Regards,
Andreas
--
[PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
CPU_UP_PREPARE)
Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
("cpu hotplug: mce: fix cpu hotplug error handling").
For CPUs not brought up during boot (using maxcpus and additional_cpus
parameters) we don't know whether mce is supported or not at
"CPU_UP_PREPARE"-time.
Thus mce_cpu_callback should be called after the CPU is online.
Signed-off-by: Andreas Herrmann <[EMAIL PROTECTED]>
---
arch/x86/kernel/cpu/mcheck/mce_64.c |6 ++
1 files changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c
b/arch/x86/kernel/cpu/mcheck/mce_64.c
index b9f802e..8e83070 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -855,12 +855,10 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned
long action, void *hcpu)
int err = 0;
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
err = mce_create_device(cpu);
break;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
mce_remove_device(cpu);
--
1.5.3.4
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Re: [PATCH] x86: fix cpu-hotplug regression
[PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
CPU_UP_PREPARE)
Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
(cpu hotplug: mce: fix cpu hotplug error handling).
For CPUs not brought up during boot (using maxcpus and additional_cpus
parameters) we don't know whether mce is supported or not at
CPU_UP_PREPARE-time.
Thus mce_cpu_callback should be called after the CPU is online.
Thank you for finding and fixing the problem.
I added two fixes to your patch:
- Avoid mce_remove_device() for the CPU that is not correctly initialized
by mce_create_device() failure.
- make CPU_ONLINE callback always return NOTIFY_OK.
Because CPU_ONLINE callback return value is always ignored.
Signed-off-by: Andreas Herrmann [EMAIL PROTECTED]
[EMAIL PROTECTED]: make CPU_ONLINE callback always return NOTIFY_OK]
[EMAIL PROTECTED]: avoid mce_remove_device() for not initialized device]
Signed-off-by: Akinobu Mita [EMAIL PROTECTED]
---
arch/x86/kernel/cpu/mcheck/mce_64.c | 18 +++---
1 file changed, 11 insertions(+), 7 deletions(-)
Index: 2.6-git/arch/x86/kernel/cpu/mcheck/mce_64.c
===
--- 2.6-git.orig/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ 2.6-git/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -802,6 +802,8 @@ static struct sysdev_attribute *mce_attr
NULL
};
+static cpumask_t mce_device_initialized = CPU_MASK_NONE;
+
/* Per cpu sysdev init. All of the cpus still share the same ctl bank */
static __cpuinit int mce_create_device(unsigned int cpu)
{
@@ -825,6 +827,7 @@ static __cpuinit int mce_create_device(u
if (err)
goto error;
}
+ cpu_set(cpu, mce_device_initialized);
return 0;
error:
@@ -841,10 +844,14 @@ static void mce_remove_device(unsigned i
{
int i;
+ if (!cpu_isset(cpu, mce_device_initialized))
+ return;
+
for (i = 0; mce_attributes[i]; i++)
sysdev_remove_file(per_cpu(device_mce,cpu),
mce_attributes[i]);
sysdev_unregister(per_cpu(device_mce,cpu));
+ cpu_clear(cpu, mce_device_initialized);
}
/* Get notified when a cpu comes on/off. Be hotplug friendly. */
@@ -852,21 +859,18 @@ static int
mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
- int err = 0;
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
- err = mce_create_device(cpu);
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ mce_create_device(cpu);
break;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
mce_remove_device(cpu);
break;
}
- return err ? NOTIFY_BAD : NOTIFY_OK;
+ return NOTIFY_OK;
}
static struct notifier_block mce_cpu_notifier = {
-
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Re: [PATCH] x86: fix cpu-hotplug regression
On Wed, Nov 07, 2007 at 03:35:43AM +0100, Andi Kleen wrote:
On Wednesday 07 November 2007 02:12, Andreas Herrmann wrote:
In cases where not all CPUs are brought up during
boot (e.g. using maxcpus and additional_cpus parameters)
mce_cpu_callback now returns NOTFIY_BAD because
for such CPUs cpu_data is not completely filled when
the notifier is called. Thus mce_create_device fails right
at its beginning:
if (!mce_available(cpu_data[cpu]))
return -EIO;
As a quick fix I suggest to check boot_cpu_data for MCE.
I guess it would be better to just move the device creation
to after the CPU has booted. AKA call mce_create_dev() on CPU_ONLINE
instead.
Yes, and this was the old behaviour. The mentioned patch changed it -
(do mce_create_device in CPU_UP_PREPARE instead of CPU_ONLINE).
Thinking twice about the problem it seems obvious that this part
of the patch should just be reverted.
Attached is a new fix (diff against 2.6.24-rc2).
Regards,
Andreas
--
[PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on
CPU_UP_PREPARE)
Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
(cpu hotplug: mce: fix cpu hotplug error handling).
For CPUs not brought up during boot (using maxcpus and additional_cpus
parameters) we don't know whether mce is supported or not at
CPU_UP_PREPARE-time.
Thus mce_cpu_callback should be called after the CPU is online.
Signed-off-by: Andreas Herrmann [EMAIL PROTECTED]
---
arch/x86/kernel/cpu/mcheck/mce_64.c |6 ++
1 files changed, 2 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c
b/arch/x86/kernel/cpu/mcheck/mce_64.c
index b9f802e..8e83070 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -855,12 +855,10 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned
long action, void *hcpu)
int err = 0;
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
err = mce_create_device(cpu);
break;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
mce_remove_device(cpu);
--
1.5.3.4
-
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Re: [PATCH] x86: fix cpu-hotplug regression
On Wednesday 07 November 2007 02:12, Andreas Herrmann wrote: > In cases where not all CPUs are brought up during > boot (e.g. using maxcpus and additional_cpus parameters) > mce_cpu_callback now returns NOTFIY_BAD because > for such CPUs cpu_data is not completely filled when > the notifier is called. Thus mce_create_device fails right > at its beginning: > > if (!mce_available(_data[cpu])) > return -EIO; > > As a quick fix I suggest to check boot_cpu_data for MCE. I guess it would be better to just move the device creation to after the CPU has booted. AKA call mce_create_dev() on CPU_ONLINE instead. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH] x86: fix cpu-hotplug regression
[PATCH] x86: fix cpu-hotplug regression
Commit d435d862baca3e25e5eec236762a43251b1e7ffc
("cpu hotplug: mce: fix cpu hotplug error handling")
changed the error handling in mce_cpu_callback.
In cases where not all CPUs are brought up during
boot (e.g. using maxcpus and additional_cpus parameters)
mce_cpu_callback now returns NOTFIY_BAD because
for such CPUs cpu_data is not completely filled when
the notifier is called. Thus mce_create_device fails right
at its beginning:
if (!mce_available(_data[cpu]))
return -EIO;
As a quick fix I suggest to check boot_cpu_data for MCE.
To reproduce this regression:
(1) boot with maxcpus=2 addtional_cpus=2 on a 4 CPU x86-64 system
(2) # echo 1 >/sys/devices/system/cpu/cpu2/online
-bash: echo: write error: Invalid argument
dmesg shows:
_cpu_up: attempt to bring up CPU 2 failed
Signed-off-by: Andreas Herrmann <[EMAIL PROTECTED]>
---
arch/x86/kernel/cpu/mcheck/mce_64.c |2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c
b/arch/x86/kernel/cpu/mcheck/mce_64.c
index b9f802e..5112a70 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -808,7 +808,7 @@ static __cpuinit int mce_create_device(unsigned int cpu)
int err;
int i;
- if (!mce_available(_data(cpu)))
+ if (!mce_available(_cpu_data))
return -EIO;
memset(_cpu(device_mce, cpu).kobj, 0, sizeof(struct kobject));
--
1.5.3.4
-
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[PATCH] x86: fix cpu-hotplug regression
[PATCH] x86: fix cpu-hotplug regression Commit d435d862baca3e25e5eec236762a43251b1e7ffc (cpu hotplug: mce: fix cpu hotplug error handling) changed the error handling in mce_cpu_callback. In cases where not all CPUs are brought up during boot (e.g. using maxcpus and additional_cpus parameters) mce_cpu_callback now returns NOTFIY_BAD because for such CPUs cpu_data is not completely filled when the notifier is called. Thus mce_create_device fails right at its beginning: if (!mce_available(cpu_data[cpu])) return -EIO; As a quick fix I suggest to check boot_cpu_data for MCE. To reproduce this regression: (1) boot with maxcpus=2 addtional_cpus=2 on a 4 CPU x86-64 system (2) # echo 1 /sys/devices/system/cpu/cpu2/online -bash: echo: write error: Invalid argument dmesg shows: _cpu_up: attempt to bring up CPU 2 failed Signed-off-by: Andreas Herrmann [EMAIL PROTECTED] --- arch/x86/kernel/cpu/mcheck/mce_64.c |2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c index b9f802e..5112a70 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_64.c +++ b/arch/x86/kernel/cpu/mcheck/mce_64.c @@ -808,7 +808,7 @@ static __cpuinit int mce_create_device(unsigned int cpu) int err; int i; - if (!mce_available(cpu_data(cpu))) + if (!mce_available(boot_cpu_data)) return -EIO; memset(per_cpu(device_mce, cpu).kobj, 0, sizeof(struct kobject)); -- 1.5.3.4 - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] x86: fix cpu-hotplug regression
On Wednesday 07 November 2007 02:12, Andreas Herrmann wrote: In cases where not all CPUs are brought up during boot (e.g. using maxcpus and additional_cpus parameters) mce_cpu_callback now returns NOTFIY_BAD because for such CPUs cpu_data is not completely filled when the notifier is called. Thus mce_create_device fails right at its beginning: if (!mce_available(cpu_data[cpu])) return -EIO; As a quick fix I suggest to check boot_cpu_data for MCE. I guess it would be better to just move the device creation to after the CPU has booted. AKA call mce_create_dev() on CPU_ONLINE instead. -Andi - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
