[PATCH] kernel/crash_core.c: No judgment required

[PATCH] kernel/crash_core.c: No judgment required

[lizhe]

No judgment required ck_cmdline is NULL
its caller has alreadly judged, see __parse_crashkernel
function

Signed-off-by: lizhe <sensor1010@163.com>
---
 kernel/crash_core.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index eb53f5ec62c9..9981cf9b9fe4 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -221,9 +221,6 @@ static __init char *get_last_crashkernel(char *cmdline,
 		p = strstr(p+1, name);
 	}
 
-	if (!ck_cmdline)
-		return NULL;
-
 	return ck_cmdline;
 }
 
-- 
2.25.1

Re: [PATCH] kernel/crash_core.c: No judgment required

[Philipp Rudo]

Hi lizhe,

On Thu,  9 Dec 2021 19:20:03 -0800
lizhe <sensor1010@163.com> wrote:

> No judgment required ck_cmdline is NULL
> its caller has alreadly judged, see __parse_crashkernel
> function
> 
> Signed-off-by: lizhe <sensor1010@163.com>
> ---
>  kernel/crash_core.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> index eb53f5ec62c9..9981cf9b9fe4 100644
> --- a/kernel/crash_core.c
> +++ b/kernel/crash_core.c
> @@ -221,9 +221,6 @@ static __init char *get_last_crashkernel(char *cmdline,
>  		p = strstr(p+1, name);
>  	}
>  
> -	if (!ck_cmdline)
> -		return NULL;
> -
>  	return ck_cmdline;
>  }
>  

I agree that the if-block is not needed and can be removed. However, I
cannot follow your reasoning in the commit message. Could you please
explain it in more detail.

The reason why I think that the 'if' can be removed is that the
expression can only be true when ck_cmdline = NULL. But with that the
last three lines are equivalent to

	if (!ck_cmdline)
		return ck_cmdline;

	return ck_cmdline;

Which simply doesn't make any sense.

Thanks
Philipp

Re: [PATCH] kernel/crash_core.c: No judgment required

[Baoquan He]

On 12/14/21 at 05:32pm, Philipp Rudo wrote:
> Hi lizhe,
> 
> On Thu,  9 Dec 2021 19:20:03 -0800
> lizhe <sensor1010@163.com> wrote:
> 
> > No judgment required ck_cmdline is NULL
> > its caller has alreadly judged, see __parse_crashkernel
> > function
> > 
> > Signed-off-by: lizhe <sensor1010@163.com>
> > ---
> >  kernel/crash_core.c | 3 ---
> >  1 file changed, 3 deletions(-)
> > 
> > diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> > index eb53f5ec62c9..9981cf9b9fe4 100644
> > --- a/kernel/crash_core.c
> > +++ b/kernel/crash_core.c
> > @@ -221,9 +221,6 @@ static __init char *get_last_crashkernel(char *cmdline,
> >  		p = strstr(p+1, name);
> >  	}
> >  
> > -	if (!ck_cmdline)
> > -		return NULL;
> > -
> >  	return ck_cmdline;
> >  }
> >  
> 
> I agree that the if-block is not needed and can be removed. However, I
> cannot follow your reasoning in the commit message. Could you please
> explain it in more detail.
> 
> The reason why I think that the 'if' can be removed is that the
> expression can only be true when ck_cmdline = NULL. But with that the
> last three lines are equivalent to
> 
> 	if (!ck_cmdline)
> 		return ck_cmdline;
> 
> 	return ck_cmdline;
> 
> Which simply doesn't make any sense.

Right, the judgement actually introduces redundant codes. As Zhe
replied, maybe you can rewrite the log and repost with your
Signed-off-by, Philipp. As for Author, you two can discuss in private
mail.

Re: [PATCH] kernel/crash_core.c: No judgment required

[Philipp Rudo]

Hi lizhe,

On Mon, 25 Apr 2022 14:22:31 +0800 (CST)
lizhe  <sensor1010@163.com> wrote:

> HI :
> 
> 
> I found the problem at the first time and gave the solution,
> 
> 
> 
> 
> Pphilipp Rudo just saw the solution to the problem and gave an explanation.
> the author of this patch should only be me

right, I only commented on the patch you sent.

Could you please update the commit message and send a v2.

Thanks
Philipp

> 
> 
> 
> 
> 
> 
> 
>                                                                                        lizhe
> 
> 
> 
> 
> 
> 
> 
> 
> At 2022-04-25 09:36:17, "Baoquan He" <bhe@redhat.com> wrote:
> >On 12/14/21 at 05:32pm, Philipp Rudo wrote:  
> >> Hi lizhe,
> >> 
> >> On Thu,  9 Dec 2021 19:20:03 -0800
> >> lizhe <sensor1010@163.com> wrote:
> >>   
> >> > No judgment required ck_cmdline is NULL
> >> > its caller has alreadly judged, see __parse_crashkernel
> >> > function
> >> > 
> >> > Signed-off-by: lizhe <sensor1010@163.com>
> >> > ---
> >> >  kernel/crash_core.c | 3 ---
> >> >  1 file changed, 3 deletions(-)
> >> > 
> >> > diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> >> > index eb53f5ec62c9..9981cf9b9fe4 100644
> >> > --- a/kernel/crash_core.c
> >> > +++ b/kernel/crash_core.c
> >> > @@ -221,9 +221,6 @@ static __init char *get_last_crashkernel(char *cmdline,
> >> >  		p = strstr(p+1, name);
> >> >  	}
> >> >  
> >> > -	if (!ck_cmdline)
> >> > -		return NULL;
> >> > -
> >> >  	return ck_cmdline;
> >> >  }
> >> >    
> >> 
> >> I agree that the if-block is not needed and can be removed. However, I
> >> cannot follow your reasoning in the commit message. Could you please
> >> explain it in more detail.
> >> 
> >> The reason why I think that the 'if' can be removed is that the
> >> expression can only be true when ck_cmdline = NULL. But with that the
> >> last three lines are equivalent to
> >> 
> >> 	if (!ck_cmdline)
> >> 		return ck_cmdline;
> >> 
> >> 	return ck_cmdline;
> >> 
> >> Which simply doesn't make any sense.  
> >
> >Right, the judgement actually introduces redundant codes. As Zhe
> >replied, maybe you can rewrite the log and repost with your
> >Signed-off-by, Philipp. As for Author, you two can discuss in private
> >mail.  

Re: [PATCH] kernel/crash_core.c: No judgment required

[Philipp Rudo]

Hi,

On Tue, 26 Apr 2022 10:17:18 +0200
Philipp Rudo <prudo@redhat.com> wrote:

> Hi lizhe,
> 
> On Mon, 25 Apr 2022 14:22:31 +0800 (CST)
> lizhe  <sensor1010@163.com> wrote:
> 
> > HI :
> > 
> > 
> > I found the problem at the first time and gave the solution,
> > 
> > 
> > 
> > 
> > Pphilipp Rudo just saw the solution to the problem and gave an explanation.
> > the author of this patch should only be me  
> 
> right, I only commented on the patch you sent.
> 
> Could you please update the commit message and send a v2.


should have checked the rest of my mails first...