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* [PATCH] kexec: quiet down kexec reboot
@ 2019-04-23 20:41 Pavel Tatashin
  2019-04-25  9:10 ` Simon Horman
  2019-04-25  9:32 ` Baoquan He
  0 siblings, 2 replies; 6+ messages in thread
From: Pavel Tatashin @ 2019-04-23 20:41 UTC (permalink / raw)
  To: pasha.tatashin, jmorris, sashal, ebiederm, kexec, linux-kernel

Here is a regular kexec command sequence and output:
=====
$ kexec --reuse-cmdline -i --load Image
$ kexec -e
[  161.342002] kexec_core: Starting new kernel

Welcome to Buildroot
buildroot login:
=====

Even when "quiet" kernel parameter is specified, "kexec_core: Starting
new kernel" is printed.

This message has  KERN_EMERG level, but there is no emergency, it is
a normal kexec operation, so quiet it down to appropriate KERN_NOTICE.

Machines that have slow console baud rate benefit from less output.

Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
---
 kernel/kexec_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
index d7140447be75..fe13e86984ec 100644
--- a/kernel/kexec_core.c
+++ b/kernel/kexec_core.c
@@ -1171,7 +1171,7 @@ int kernel_kexec(void)
 		 * CPU hotplug again; so re-enable it here.
 		 */
 		cpu_hotplug_enable();
-		pr_emerg("Starting new kernel\n");
+		pr_notice("Starting new kernel\n");
 		machine_shutdown();
 	}
 
-- 
2.21.0


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] kexec: quiet down kexec reboot
  2019-04-23 20:41 [PATCH] kexec: quiet down kexec reboot Pavel Tatashin
@ 2019-04-25  9:10 ` Simon Horman
  2019-04-25 12:13   ` Pavel Tatashin
  2019-04-25  9:32 ` Baoquan He
  1 sibling, 1 reply; 6+ messages in thread
From: Simon Horman @ 2019-04-25  9:10 UTC (permalink / raw)
  To: Pavel Tatashin; +Cc: jmorris, sashal, ebiederm, kexec, linux-kernel

On Tue, Apr 23, 2019 at 04:41:54PM -0400, Pavel Tatashin wrote:
> Here is a regular kexec command sequence and output:
> =====
> $ kexec --reuse-cmdline -i --load Image
> $ kexec -e
> [  161.342002] kexec_core: Starting new kernel
> 
> Welcome to Buildroot
> buildroot login:
> =====
> 
> Even when "quiet" kernel parameter is specified, "kexec_core: Starting
> new kernel" is printed.
> 
> This message has  KERN_EMERG level, but there is no emergency, it is
> a normal kexec operation, so quiet it down to appropriate KERN_NOTICE.
> 
> Machines that have slow console baud rate benefit from less output.
> 
> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>

Reviewed-by: Simon Horman <horms@verge.net.au>

> ---
>  kernel/kexec_core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index d7140447be75..fe13e86984ec 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -1171,7 +1171,7 @@ int kernel_kexec(void)
>  		 * CPU hotplug again; so re-enable it here.
>  		 */
>  		cpu_hotplug_enable();
> -		pr_emerg("Starting new kernel\n");
> +		pr_notice("Starting new kernel\n");
>  		machine_shutdown();
>  	}
>  
> -- 
> 2.21.0
> 
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
> 

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] kexec: quiet down kexec reboot
  2019-04-23 20:41 [PATCH] kexec: quiet down kexec reboot Pavel Tatashin
  2019-04-25  9:10 ` Simon Horman
@ 2019-04-25  9:32 ` Baoquan He
  2019-04-25  9:41   ` Baoquan He
  1 sibling, 1 reply; 6+ messages in thread
From: Baoquan He @ 2019-04-25  9:32 UTC (permalink / raw)
  To: Pavel Tatashin; +Cc: jmorris, sashal, ebiederm, dyoung, kexec, linux-kernel

On 04/23/19 at 04:41pm, Pavel Tatashin wrote:
> Here is a regular kexec command sequence and output:
> =====
> $ kexec --reuse-cmdline -i --load Image
> $ kexec -e
> [  161.342002] kexec_core: Starting new kernel
> 
> Welcome to Buildroot
> buildroot login:
> =====
> 
> Even when "quiet" kernel parameter is specified, "kexec_core: Starting
> new kernel" is printed.

I personally don't like this change very much. 

kernel-parameters.txt tells that quiet disables most log messages, but
not to disable log messages.

	quiet           [KNL] Disable most log messages 

And kexec doesn't print many messages. When 'kexec -e' is executed,
much critical work need be done in 1st kernel, and also in 2nd kernel
till printed messages are seen. Sometime it could hang there without a
notice, because we need shutdown all devices before it. Keeping it can
at least tell which stage it is?

No strong objection, just we may need enable it manually if silent
hang is met. Anyone has different opinion? 

Thanks
Baoquan

> 
> This message has  KERN_EMERG level, but there is no emergency, it is
> a normal kexec operation, so quiet it down to appropriate KERN_NOTICE.
> 
> Machines that have slow console baud rate benefit from less output.
> 
> Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
> ---
>  kernel/kexec_core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index d7140447be75..fe13e86984ec 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -1171,7 +1171,7 @@ int kernel_kexec(void)
>  		 * CPU hotplug again; so re-enable it here.
>  		 */
>  		cpu_hotplug_enable();
> -		pr_emerg("Starting new kernel\n");
> +		pr_notice("Starting new kernel\n");
>  		machine_shutdown();
>  	}
>  
> -- 
> 2.21.0
> 
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] kexec: quiet down kexec reboot
  2019-04-25  9:32 ` Baoquan He
@ 2019-04-25  9:41   ` Baoquan He
  2019-04-25 12:12     ` Pavel Tatashin
  0 siblings, 1 reply; 6+ messages in thread
From: Baoquan He @ 2019-04-25  9:41 UTC (permalink / raw)
  To: Pavel Tatashin; +Cc: sashal, kexec, jmorris, linux-kernel, ebiederm, dyoung

On 04/25/19 at 05:32pm, Baoquan He wrote:
> On 04/23/19 at 04:41pm, Pavel Tatashin wrote:
> > Here is a regular kexec command sequence and output:
> > =====
> > $ kexec --reuse-cmdline -i --load Image
> > $ kexec -e
> > [  161.342002] kexec_core: Starting new kernel
> > 
> > Welcome to Buildroot
> > buildroot login:
> > =====
> > 
> > Even when "quiet" kernel parameter is specified, "kexec_core: Starting
> > new kernel" is printed.
> 
> I personally don't like this change very much. 
> 
> kernel-parameters.txt tells that quiet disables most log messages, but
> not to disable log messages.
> 
> 	quiet           [KNL] Disable most log messages 
> 
> And kexec doesn't print many messages. When 'kexec -e' is executed,
> much critical work need be done in 1st kernel, and also in 2nd kernel
> till printed messages are seen. Sometime it could hang there without a
> notice, because we need shutdown all devices before it. Keeping it can
> at least tell which stage it is?
> 
> No strong objection, just we may need enable it manually if silent
> hang is met. Anyone has different opinion? 

Please ignore this mail, I must be dizzy. pr_notice looks good to me.

> > 
> > This message has  KERN_EMERG level, but there is no emergency, it is
> > a normal kexec operation, so quiet it down to appropriate KERN_NOTICE.
> > 
> > Machines that have slow console baud rate benefit from less output.
> > 
> > Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
> > ---
> >  kernel/kexec_core.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> > index d7140447be75..fe13e86984ec 100644
> > --- a/kernel/kexec_core.c
> > +++ b/kernel/kexec_core.c
> > @@ -1171,7 +1171,7 @@ int kernel_kexec(void)
> >  		 * CPU hotplug again; so re-enable it here.
> >  		 */
> >  		cpu_hotplug_enable();
> > -		pr_emerg("Starting new kernel\n");
> > +		pr_notice("Starting new kernel\n");
> >  		machine_shutdown();
> >  	}
> >  
> > -- 
> > 2.21.0
> > 
> > 
> > _______________________________________________
> > kexec mailing list
> > kexec@lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/kexec
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] kexec: quiet down kexec reboot
  2019-04-25  9:41   ` Baoquan He
@ 2019-04-25 12:12     ` Pavel Tatashin
  0 siblings, 0 replies; 6+ messages in thread
From: Pavel Tatashin @ 2019-04-25 12:12 UTC (permalink / raw)
  To: Baoquan He; +Cc: Sasha Levin, kexec, James Morris, LKML, ebiederm, dyoung

> > And kexec doesn't print many messages. When 'kexec -e' is executed,
> > much critical work need be done in 1st kernel, and also in 2nd kernel
> > till printed messages are seen. Sometime it could hang there without a
> > notice, because we need shutdown all devices before it. Keeping it can
> > at least tell which stage it is?
> >
> > No strong objection, just we may need enable it manually if silent
> > hang is met. Anyone has different opinion?
>
> Please ignore this mail, I must be dizzy. pr_notice looks good to me.
>

Thank you for looking at this.

Pasha

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] kexec: quiet down kexec reboot
  2019-04-25  9:10 ` Simon Horman
@ 2019-04-25 12:13   ` Pavel Tatashin
  0 siblings, 0 replies; 6+ messages in thread
From: Pavel Tatashin @ 2019-04-25 12:13 UTC (permalink / raw)
  To: Simon Horman; +Cc: James Morris, Sasha Levin, ebiederm, kexec, LKML

> > Machines that have slow console baud rate benefit from less output.
> >
> > Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
>
> Reviewed-by: Simon Horman <horms@verge.net.au>
>

Thank you for reviewing.

Pasha

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2019-04-25 12:13 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-04-23 20:41 [PATCH] kexec: quiet down kexec reboot Pavel Tatashin
2019-04-25  9:10 ` Simon Horman
2019-04-25 12:13   ` Pavel Tatashin
2019-04-25  9:32 ` Baoquan He
2019-04-25  9:41   ` Baoquan He
2019-04-25 12:12     ` Pavel Tatashin

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