* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-08 15:14 ` Vivek Goyal
@ 2013-11-08 16:12 ` H. Peter Anvin
2013-11-08 16:24 ` Vivek Goyal
2013-11-11 15:29 ` Vivek Goyal
2013-11-10 9:44 ` Baoquan He
2013-11-11 6:55 ` WANG Chao
2 siblings, 2 replies; 16+ messages in thread
From: H. Peter Anvin @ 2013-11-08 16:12 UTC (permalink / raw)
To: Vivek Goyal, Baoquan He
Cc: linux-kernel, tglx, mingo, x86, akpm, davej, rmk+kernel, chaowang,
mwhitehe, kexec, Eric W. Biederman, Robin Holt, Robin Holt
On 11/08/2013 07:14 AM, Vivek Goyal wrote:
>
> Hi Bao,
>
> This patch fixes the issue for me too. I noticed that we have generic
> function migrate_to_reboot_cpu() to achieve what we want and rest of
> the reboot paths are using it. So how about using that function. I
> wrote the new patch below. It works for me. Can you please give it
> a try.
>
> Thanks
> Vivek
>
Is this path exercised for the kdump flow? migrate_to_reboot_cpu() is
unsafe in that case.
> Index: linux-2.6/kernel/kexec.c
> ===================================================================
> --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> #endif
> {
> kernel_restart_prepare(NULL);
> + migrate_to_reboot_cpu();
> printk(KERN_EMERG "Starting new kernel\n");
> machine_shutdown();
> }
>
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-08 16:12 ` H. Peter Anvin
@ 2013-11-08 16:24 ` Vivek Goyal
2013-11-11 15:29 ` Vivek Goyal
1 sibling, 0 replies; 16+ messages in thread
From: Vivek Goyal @ 2013-11-08 16:24 UTC (permalink / raw)
To: H. Peter Anvin
Cc: Baoquan He, linux-kernel, tglx, mingo, x86, akpm, davej,
rmk+kernel, chaowang, mwhitehe, kexec, Eric W. Biederman,
Robin Holt, Robin Holt
On Fri, Nov 08, 2013 at 08:12:00AM -0800, H. Peter Anvin wrote:
> On 11/08/2013 07:14 AM, Vivek Goyal wrote:
> >
> > Hi Bao,
> >
> > This patch fixes the issue for me too. I noticed that we have generic
> > function migrate_to_reboot_cpu() to achieve what we want and rest of
> > the reboot paths are using it. So how about using that function. I
> > wrote the new patch below. It works for me. Can you please give it
> > a try.
> >
> > Thanks
> > Vivek
> >
>
> Is this path exercised for the kdump flow? migrate_to_reboot_cpu() is
> unsafe in that case.
kdump path should not be affected by this change as it uses crash_kexec()
instead of kerenl_kexec() for its entry. And crash_kexec() path does not
call migrate_to_reboot_cpu().
Thanks
Vivek
>
> > Index: linux-2.6/kernel/kexec.c
> > ===================================================================
> > --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> > +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> > @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> > #endif
> > {
> > kernel_restart_prepare(NULL);
> > + migrate_to_reboot_cpu();
> > printk(KERN_EMERG "Starting new kernel\n");
> > machine_shutdown();
> > }
> >
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-08 16:12 ` H. Peter Anvin
2013-11-08 16:24 ` Vivek Goyal
@ 2013-11-11 15:29 ` Vivek Goyal
2013-11-11 15:39 ` H. Peter Anvin
1 sibling, 1 reply; 16+ messages in thread
From: Vivek Goyal @ 2013-11-11 15:29 UTC (permalink / raw)
To: H. Peter Anvin
Cc: Baoquan He, linux-kernel, tglx, mingo, x86, akpm, davej,
rmk+kernel, chaowang, mwhitehe, kexec, Eric W. Biederman,
Robin Holt, Robin Holt
On Fri, Nov 08, 2013 at 08:12:00AM -0800, H. Peter Anvin wrote:
> On 11/08/2013 07:14 AM, Vivek Goyal wrote:
> >
> > Hi Bao,
> >
> > This patch fixes the issue for me too. I noticed that we have generic
> > function migrate_to_reboot_cpu() to achieve what we want and rest of
> > the reboot paths are using it. So how about using that function. I
> > wrote the new patch below. It works for me. Can you please give it
> > a try.
> >
> > Thanks
> > Vivek
> >
>
> Is this path exercised for the kdump flow? migrate_to_reboot_cpu() is
> unsafe in that case.
Hi Peter,
Can you please consider queuing up this patch for next release.
Thanks
Vivek
>
> > Index: linux-2.6/kernel/kexec.c
> > ===================================================================
> > --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> > +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> > @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> > #endif
> > {
> > kernel_restart_prepare(NULL);
> > + migrate_to_reboot_cpu();
> > printk(KERN_EMERG "Starting new kernel\n");
> > machine_shutdown();
> > }
> >
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-11 15:29 ` Vivek Goyal
@ 2013-11-11 15:39 ` H. Peter Anvin
2013-11-11 15:57 ` Vivek Goyal
0 siblings, 1 reply; 16+ messages in thread
From: H. Peter Anvin @ 2013-11-11 15:39 UTC (permalink / raw)
To: Vivek Goyal
Cc: Baoquan He, linux-kernel, tglx, mingo, x86, akpm, davej,
rmk+kernel, chaowang, mwhitehe, kexec, Eric W. Biederman,
Robin Holt, Robin Holt
Yes, unless there is a better path for it since it is not x86-specific. I am fine taking it, though.
Vivek Goyal <vgoyal@redhat.com> wrote:
>On Fri, Nov 08, 2013 at 08:12:00AM -0800, H. Peter Anvin wrote:
>> On 11/08/2013 07:14 AM, Vivek Goyal wrote:
>> >
>> > Hi Bao,
>> >
>> > This patch fixes the issue for me too. I noticed that we have
>generic
>> > function migrate_to_reboot_cpu() to achieve what we want and rest
>of
>> > the reboot paths are using it. So how about using that function. I
>> > wrote the new patch below. It works for me. Can you please give it
>> > a try.
>> >
>> > Thanks
>> > Vivek
>> >
>>
>> Is this path exercised for the kdump flow? migrate_to_reboot_cpu()
>is
>> unsafe in that case.
>
>Hi Peter,
>
>Can you please consider queuing up this patch for next release.
>
>Thanks
>Vivek
>
>>
>> > Index: linux-2.6/kernel/kexec.c
>> > ===================================================================
>> > --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000
>-0400
>> > +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
>> > @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
>> > #endif
>> > {
>> > kernel_restart_prepare(NULL);
>> > + migrate_to_reboot_cpu();
>> > printk(KERN_EMERG "Starting new kernel\n");
>> > machine_shutdown();
>> > }
>> >
--
Sent from my mobile phone. Please pardon brevity and lack of formatting.
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-11 15:39 ` H. Peter Anvin
@ 2013-11-11 15:57 ` Vivek Goyal
2013-11-11 16:02 ` H. Peter Anvin
0 siblings, 1 reply; 16+ messages in thread
From: Vivek Goyal @ 2013-11-11 15:57 UTC (permalink / raw)
To: H. Peter Anvin, Andrew Morton
Cc: Baoquan He, linux-kernel, tglx, mingo, x86, davej, rmk+kernel,
chaowang, mwhitehe, kexec, Eric W. Biederman, Robin Holt,
Robin Holt
On Mon, Nov 11, 2013 at 07:39:18AM -0800, H. Peter Anvin wrote:
> Yes, unless there is a better path for it since it is not x86-specific. I am fine taking it, though.
Generally Andrew Morton routes kexec/kdump patches through his tree. Andrew,
do you think it should go through your tree?
Thanks
Vivek
>
> Vivek Goyal <vgoyal@redhat.com> wrote:
> >On Fri, Nov 08, 2013 at 08:12:00AM -0800, H. Peter Anvin wrote:
> >> On 11/08/2013 07:14 AM, Vivek Goyal wrote:
> >> >
> >> > Hi Bao,
> >> >
> >> > This patch fixes the issue for me too. I noticed that we have
> >generic
> >> > function migrate_to_reboot_cpu() to achieve what we want and rest
> >of
> >> > the reboot paths are using it. So how about using that function. I
> >> > wrote the new patch below. It works for me. Can you please give it
> >> > a try.
> >> >
> >> > Thanks
> >> > Vivek
> >> >
> >>
> >> Is this path exercised for the kdump flow? migrate_to_reboot_cpu()
> >is
> >> unsafe in that case.
> >
> >Hi Peter,
> >
> >Can you please consider queuing up this patch for next release.
> >
> >Thanks
> >Vivek
> >
> >>
> >> > Index: linux-2.6/kernel/kexec.c
> >> > ===================================================================
> >> > --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000
> >-0400
> >> > +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> >> > @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> >> > #endif
> >> > {
> >> > kernel_restart_prepare(NULL);
> >> > + migrate_to_reboot_cpu();
> >> > printk(KERN_EMERG "Starting new kernel\n");
> >> > machine_shutdown();
> >> > }
> >> >
>
> --
> Sent from my mobile phone. Please pardon brevity and lack of formatting.
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-11 15:57 ` Vivek Goyal
@ 2013-11-11 16:02 ` H. Peter Anvin
0 siblings, 0 replies; 16+ messages in thread
From: H. Peter Anvin @ 2013-11-11 16:02 UTC (permalink / raw)
To: Vivek Goyal, Andrew Morton
Cc: Baoquan He, linux-kernel, tglx, mingo, x86, davej, rmk+kernel,
chaowang, mwhitehe, kexec, Eric W. Biederman, Robin Holt,
Robin Holt
On 11/11/2013 07:57 AM, Vivek Goyal wrote:
> On Mon, Nov 11, 2013 at 07:39:18AM -0800, H. Peter Anvin wrote:
>> Yes, unless there is a better path for it since it is not x86-specific. I am fine taking it, though.
>
> Generally Andrew Morton routes kexec/kdump patches through his tree. Andrew,
> do you think it should go through your tree?
>
> Thanks
> Vivek
If so, you can have my:
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
-hpa
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-08 15:14 ` Vivek Goyal
2013-11-08 16:12 ` H. Peter Anvin
@ 2013-11-10 9:44 ` Baoquan He
2013-11-11 6:52 ` Baoquan He
2013-11-11 6:55 ` WANG Chao
2 siblings, 1 reply; 16+ messages in thread
From: Baoquan He @ 2013-11-10 9:44 UTC (permalink / raw)
To: Vivek Goyal
Cc: linux-kernel, tglx, mingo, hpa, x86, akpm, davej, rmk+kernel,
chaowang, mwhitehe, kexec, Eric W. Biederman, Robin Holt,
Robin Holt
On 11/08/13 at 10:14am, Vivek Goyal wrote:
> On Tue, Nov 05, 2013 at 05:16:07PM +0800, Baoquan He wrote:
>
> Hi Bao,
>
> This patch fixes the issue for me too. I noticed that we have generic
> function migrate_to_reboot_cpu() to achieve what we want and rest of
> the reboot paths are using it. So how about using that function. I
> wrote the new patch below. It works for me. Can you please give it
> a try.
Seems there's something wrong with this function, that error happened
when I executed the 2nd "kexec -e". That means executing "kexec -e" in
kexec-ed kernel.
Tomorrow I will ask people around take more tests. We need set affinity
to test this. E.g always execute :
taskset -c 1 -sh "kexec -e"
>
> Thanks
> Vivek
>
> kexec: migrate to reboot cpu
>
> Commit 1b3a5d02ee070c8f9943333b9b6370f486601e0f moved reboot= handling to
> generic code. In the process it also removed the code in
> native_machine_shutdown() which are moving reboot process to reboot_cpu/cpu0.
>
> I guess that thought must have been that all reboot paths are calling
> migrate_to_reboot_cpu(), so we don't need this special handling. But
> kexec reboot path (kernel_kexec()) is not calling migrate_to_reboot_cpu()
> so above change broke kexec. Now reboot can happen on non-boot cpu and when
> INIT is sent in second kerneo to bring up BP, it brings down the machine.
>
> So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
> this problem.
>
> Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
> Reported-by: Dave Young <dyoung@redhat.com>
> Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
> ---
> include/linux/reboot.h | 1 +
> kernel/kexec.c | 1 +
> kernel/reboot.c | 2 +-
> 3 files changed, 3 insertions(+), 1 deletion(-)
>
> Index: linux-2.6/kernel/reboot.c
> ===================================================================
> --- linux-2.6.orig/kernel/reboot.c 2013-10-16 00:30:50.000000000 -0400
> +++ linux-2.6/kernel/reboot.c 2013-11-08 21:31:03.379064848 -0500
> @@ -104,7 +104,7 @@ int unregister_reboot_notifier(struct no
> }
> EXPORT_SYMBOL(unregister_reboot_notifier);
>
> -static void migrate_to_reboot_cpu(void)
> +void migrate_to_reboot_cpu(void)
> {
> /* The boot cpu is always logical cpu 0 */
> int cpu = reboot_cpu;
> Index: linux-2.6/include/linux/reboot.h
> ===================================================================
> --- linux-2.6.orig/include/linux/reboot.h 2013-11-08 21:33:27.000000000 -0500
> +++ linux-2.6/include/linux/reboot.h 2013-11-08 21:34:29.778073522 -0500
> @@ -43,6 +43,7 @@ extern int unregister_reboot_notifier(st
> * Architecture-specific implementations of sys_reboot commands.
> */
>
> +extern void migrate_to_reboot_cpu(void);
> extern void machine_restart(char *cmd);
> extern void machine_halt(void);
> extern void machine_power_off(void);
> Index: linux-2.6/kernel/kexec.c
> ===================================================================
> --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> #endif
> {
> kernel_restart_prepare(NULL);
> + migrate_to_reboot_cpu();
> printk(KERN_EMERG "Starting new kernel\n");
> machine_shutdown();
> }
^ permalink raw reply [flat|nested] 16+ messages in thread* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-10 9:44 ` Baoquan He
@ 2013-11-11 6:52 ` Baoquan He
0 siblings, 0 replies; 16+ messages in thread
From: Baoquan He @ 2013-11-11 6:52 UTC (permalink / raw)
To: Vivek Goyal
Cc: linux-kernel, tglx, mingo, hpa, x86, akpm, davej, rmk+kernel,
chaowang, mwhitehe, kexec, Eric W. Biederman, Robin Holt,
Robin Holt
On 11/10/13 at 05:44pm, Baoquan He wrote:
> On 11/08/13 at 10:14am, Vivek Goyal wrote:
> > On Tue, Nov 05, 2013 at 05:16:07PM +0800, Baoquan He wrote:
>
> >
> > Hi Bao,
> >
> > This patch fixes the issue for me too. I noticed that we have generic
> > function migrate_to_reboot_cpu() to achieve what we want and rest of
> > the reboot paths are using it. So how about using that function. I
> > wrote the new patch below. It works for me. Can you please give it
> > a try.
Hi Vivek,
Your patch works, my test script has wrong typo.
Baoquan
Thanks a lot
>
> Seems there's something wrong with this function, that error happened
> when I executed the 2nd "kexec -e". That means executing "kexec -e" in
> kexec-ed kernel.
>
> Tomorrow I will ask people around take more tests. We need set affinity
> to test this. E.g always execute :
>
> taskset -c 1 -sh "kexec -e"
>
>
> >
> > Thanks
> > Vivek
> >
> > kexec: migrate to reboot cpu
> >
> > Commit 1b3a5d02ee070c8f9943333b9b6370f486601e0f moved reboot= handling to
> > generic code. In the process it also removed the code in
> > native_machine_shutdown() which are moving reboot process to reboot_cpu/cpu0.
> >
> > I guess that thought must have been that all reboot paths are calling
> > migrate_to_reboot_cpu(), so we don't need this special handling. But
> > kexec reboot path (kernel_kexec()) is not calling migrate_to_reboot_cpu()
> > so above change broke kexec. Now reboot can happen on non-boot cpu and when
> > INIT is sent in second kerneo to bring up BP, it brings down the machine.
> >
> > So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
> > this problem.
> >
> > Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
> > Reported-by: Dave Young <dyoung@redhat.com>
> > Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
> > ---
> > include/linux/reboot.h | 1 +
> > kernel/kexec.c | 1 +
> > kernel/reboot.c | 2 +-
> > 3 files changed, 3 insertions(+), 1 deletion(-)
> >
> > Index: linux-2.6/kernel/reboot.c
> > ===================================================================
> > --- linux-2.6.orig/kernel/reboot.c 2013-10-16 00:30:50.000000000 -0400
> > +++ linux-2.6/kernel/reboot.c 2013-11-08 21:31:03.379064848 -0500
> > @@ -104,7 +104,7 @@ int unregister_reboot_notifier(struct no
> > }
> > EXPORT_SYMBOL(unregister_reboot_notifier);
> >
> > -static void migrate_to_reboot_cpu(void)
> > +void migrate_to_reboot_cpu(void)
> > {
> > /* The boot cpu is always logical cpu 0 */
> > int cpu = reboot_cpu;
> > Index: linux-2.6/include/linux/reboot.h
> > ===================================================================
> > --- linux-2.6.orig/include/linux/reboot.h 2013-11-08 21:33:27.000000000 -0500
> > +++ linux-2.6/include/linux/reboot.h 2013-11-08 21:34:29.778073522 -0500
> > @@ -43,6 +43,7 @@ extern int unregister_reboot_notifier(st
> > * Architecture-specific implementations of sys_reboot commands.
> > */
> >
> > +extern void migrate_to_reboot_cpu(void);
> > extern void machine_restart(char *cmd);
> > extern void machine_halt(void);
> > extern void machine_power_off(void);
> > Index: linux-2.6/kernel/kexec.c
> > ===================================================================
> > --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> > +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> > @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> > #endif
> > {
> > kernel_restart_prepare(NULL);
> > + migrate_to_reboot_cpu();
> > printk(KERN_EMERG "Starting new kernel\n");
> > machine_shutdown();
> > }
^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: [PATCH] x86: make reboot task only run on the appropriate processor
2013-11-08 15:14 ` Vivek Goyal
2013-11-08 16:12 ` H. Peter Anvin
2013-11-10 9:44 ` Baoquan He
@ 2013-11-11 6:55 ` WANG Chao
2 siblings, 0 replies; 16+ messages in thread
From: WANG Chao @ 2013-11-11 6:55 UTC (permalink / raw)
To: Vivek Goyal
Cc: Baoquan He, linux-kernel, tglx, mingo, hpa, x86, akpm, davej,
rmk+kernel, mwhitehe, kexec, Eric W. Biederman, Robin Holt,
Robin Holt
On 11/08/13 at 10:14am, Vivek Goyal wrote:
> On Tue, Nov 05, 2013 at 05:16:07PM +0800, Baoquan He wrote:
> > Currently system always reboot after below message when execute "kexec -e".
> >
> > [ 0.572119] smpboot: Booting Node 0, Processors # 1 OK
> >
> > In commit 1b3a5d02ee070c8f9943333b9b6370f486601e0f, reboot= handling was
> > moved to kerne/reboot.c. However, the code to migrate current thread to
> > reboot cpu was removed. That cause this incorrect kexec behavior.
> >
> > Now add that code block back.
> >
> > Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
> > Reported-by: Dave Young <dyoung@redhat.com>
> > Tested-by: WANG Chao <chaowang@redhat.com>
> > Signed-off-by: Baoquan He <bhe@redhat.com>
>
> Hi Bao,
>
> This patch fixes the issue for me too. I noticed that we have generic
> function migrate_to_reboot_cpu() to achieve what we want and rest of
> the reboot paths are using it. So how about using that function. I
> wrote the new patch below. It works for me. Can you please give it
> a try.
Hi, Vivek
I confirm this patch works for me, even in a nested kexec scenario. Feel
free to add these:
Bisected-by: WANG Chao <chaowang@redhat.com>
Tested-by: WANG Chao <chaowang@redhat.com>
Thanks
WANG Chao
>
> Thanks
> Vivek
>
> kexec: migrate to reboot cpu
>
> Commit 1b3a5d02ee070c8f9943333b9b6370f486601e0f moved reboot= handling to
> generic code. In the process it also removed the code in
> native_machine_shutdown() which are moving reboot process to reboot_cpu/cpu0.
>
> I guess that thought must have been that all reboot paths are calling
> migrate_to_reboot_cpu(), so we don't need this special handling. But
> kexec reboot path (kernel_kexec()) is not calling migrate_to_reboot_cpu()
> so above change broke kexec. Now reboot can happen on non-boot cpu and when
> INIT is sent in second kerneo to bring up BP, it brings down the machine.
>
> So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
> this problem.
>
> Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
> Reported-by: Dave Young <dyoung@redhat.com>
> Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
> ---
> include/linux/reboot.h | 1 +
> kernel/kexec.c | 1 +
> kernel/reboot.c | 2 +-
> 3 files changed, 3 insertions(+), 1 deletion(-)
>
> Index: linux-2.6/kernel/reboot.c
> ===================================================================
> --- linux-2.6.orig/kernel/reboot.c 2013-10-16 00:30:50.000000000 -0400
> +++ linux-2.6/kernel/reboot.c 2013-11-08 21:31:03.379064848 -0500
> @@ -104,7 +104,7 @@ int unregister_reboot_notifier(struct no
> }
> EXPORT_SYMBOL(unregister_reboot_notifier);
>
> -static void migrate_to_reboot_cpu(void)
> +void migrate_to_reboot_cpu(void)
> {
> /* The boot cpu is always logical cpu 0 */
> int cpu = reboot_cpu;
> Index: linux-2.6/include/linux/reboot.h
> ===================================================================
> --- linux-2.6.orig/include/linux/reboot.h 2013-11-08 21:33:27.000000000 -0500
> +++ linux-2.6/include/linux/reboot.h 2013-11-08 21:34:29.778073522 -0500
> @@ -43,6 +43,7 @@ extern int unregister_reboot_notifier(st
> * Architecture-specific implementations of sys_reboot commands.
> */
>
> +extern void migrate_to_reboot_cpu(void);
> extern void machine_restart(char *cmd);
> extern void machine_halt(void);
> extern void machine_power_off(void);
> Index: linux-2.6/kernel/kexec.c
> ===================================================================
> --- linux-2.6.orig/kernel/kexec.c 2013-10-16 00:30:50.000000000 -0400
> +++ linux-2.6/kernel/kexec.c 2013-11-08 21:34:02.492072375 -0500
> @@ -1676,6 +1676,7 @@ int kernel_kexec(void)
> #endif
> {
> kernel_restart_prepare(NULL);
> + migrate_to_reboot_cpu();
> printk(KERN_EMERG "Starting new kernel\n");
> machine_shutdown();
> }
^ permalink raw reply [flat|nested] 16+ messages in thread