[PATCH v2 1/1] kdump: append uts_namespace.name offset to VMCOREINFO

[PATCH v2 1/1] kdump: append uts_namespace.name offset to VMCOREINFO

[Alexander Egorenkov]

The offset of the field 'init_uts_ns.name' has changed
since

commit 9a56493f6942c0e2df1579986128721da96e00d8
Author: Kirill Tkhai <ktkhai@virtuozzo.com>
Date:   Mon Aug 3 13:16:21 2020 +0300

    uts: Use generic ns_common::count

Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain

Make the offset of the field 'uts_namespace.name' available
in VMCOREINFO because tools like 'crash-utility' and
'makedumpfile' must be able to read it from crash dumps.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
---
 kernel/crash_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index 106e4500fd53..173fdc261882 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -447,6 +447,7 @@ static int __init crash_save_vmcoreinfo_init(void)
 	VMCOREINFO_PAGESIZE(PAGE_SIZE);
 
 	VMCOREINFO_SYMBOL(init_uts_ns);
+	VMCOREINFO_OFFSET(uts_namespace, name);
 	VMCOREINFO_SYMBOL(node_online_map);
 #ifdef CONFIG_MMU
 	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
-- 
2.26.2

Re: [PATCH v2 1/1] kdump: append uts_namespace.name offset to VMCOREINFO

[Baoquan He]

On 09/24/20 at 02:46pm, Alexander Egorenkov wrote:
> The offset of the field 'init_uts_ns.name' has changed
> since
> 
> commit 9a56493f6942c0e2df1579986128721da96e00d8
> Author: Kirill Tkhai <ktkhai@virtuozzo.com>
> Date:   Mon Aug 3 13:16:21 2020 +0300
> 
>     uts: Use generic ns_common::count
> 
> Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain

Seems there's some argument about the generic ns_common::count in the
thread of above link. While except of it, the adding the offset of
uts_namespace.name looks good to me.

Acked-by: Baoquan He <bhe@redhat.com>


> 
> Make the offset of the field 'uts_namespace.name' available
> in VMCOREINFO because tools like 'crash-utility' and
> 'makedumpfile' must be able to read it from crash dumps.
> 
> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
> ---
>  kernel/crash_core.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> index 106e4500fd53..173fdc261882 100644
> --- a/kernel/crash_core.c
> +++ b/kernel/crash_core.c
> @@ -447,6 +447,7 @@ static int __init crash_save_vmcoreinfo_init(void)
>  	VMCOREINFO_PAGESIZE(PAGE_SIZE);
>  
>  	VMCOREINFO_SYMBOL(init_uts_ns);
> +	VMCOREINFO_OFFSET(uts_namespace, name);
>  	VMCOREINFO_SYMBOL(node_online_map);
>  #ifdef CONFIG_MMU
>  	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
> -- 
> 2.26.2
> 

Re: [PATCH v2 1/1] kdump: append uts_namespace.name offset to VMCOREINFO

[Bhupesh Sharma]

Hi Alexander,

On Thu, Sep 24, 2020 at 6:18 PM Alexander Egorenkov
<egorenar@linux.ibm.com> wrote:
>
> The offset of the field 'init_uts_ns.name' has changed
> since
>
> commit 9a56493f6942c0e2df1579986128721da96e00d8
> Author: Kirill Tkhai <ktkhai@virtuozzo.com>
> Date:   Mon Aug 3 13:16:21 2020 +0300
>
>     uts: Use generic ns_common::count

A minor nitpick:
You can add the following line to your .gitconfig:
one = show -s --pretty='format:%h (\"%s\")'

running a command '$ git one <SHA-ID>' will then give you an
abbreviated form to be used while referring to existing git commits in
the log message. For e.g. in this case, the output would be something
like:

$ git one 9a56493f6942c0e2df1579986128721da96e00d8
9a56493f6942 ("uts: Use generic ns_common::count")

Then you can use '9a56493f6942 ("uts: Use generic ns_common::count")'
to refer to an existing upstream patch in the log message.

But I think this can be fixed while applying the patch (if there are
no further revisions required).

> Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain
>
> Make the offset of the field 'uts_namespace.name' available
> in VMCOREINFO because tools like 'crash-utility' and
> 'makedumpfile' must be able to read it from crash dumps.
>
> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
> ---
>  kernel/crash_core.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> index 106e4500fd53..173fdc261882 100644
> --- a/kernel/crash_core.c
> +++ b/kernel/crash_core.c
> @@ -447,6 +447,7 @@ static int __init crash_save_vmcoreinfo_init(void)
>         VMCOREINFO_PAGESIZE(PAGE_SIZE);
>
>         VMCOREINFO_SYMBOL(init_uts_ns);
> +       VMCOREINFO_OFFSET(uts_namespace, name);
>         VMCOREINFO_SYMBOL(node_online_map);
>  #ifdef CONFIG_MMU
>         VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
> --
> 2.26.2

Thanks for making the changes we discussed in the v1 review. Otherwise
the patch looks fine to me, so:

Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>

Re: [PATCH v2 1/1] kdump: append uts_namespace.name offset to VMCOREINFO

[lijiang]

Hi, Alexander

在 2020年09月24日 20:46, Alexander Egorenkov 写道:
> The offset of the field 'init_uts_ns.name' has changed
> since
> 
> commit 9a56493f6942c0e2df1579986128721da96e00d8
> Author: Kirill Tkhai <ktkhai@virtuozzo.com>
> Date:   Mon Aug 3 13:16:21 2020 +0300
> 
>     uts: Use generic ns_common::count
> 
> Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain
> 
> Make the offset of the field 'uts_namespace.name' available
> in VMCOREINFO because tools like 'crash-utility' and
> 'makedumpfile' must be able to read it from crash dumps.
> 
> Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
> ---
>  kernel/crash_core.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/kernel/crash_core.c b/kernel/crash_core.c
> index 106e4500fd53..173fdc261882 100644
> --- a/kernel/crash_core.c
> +++ b/kernel/crash_core.c
> @@ -447,6 +447,7 @@ static int __init crash_save_vmcoreinfo_init(void)
>  	VMCOREINFO_PAGESIZE(PAGE_SIZE);
>  
>  	VMCOREINFO_SYMBOL(init_uts_ns);
> +	VMCOREINFO_OFFSET(uts_namespace, name);

Since the new symbol is exported, would you mind adding it to Documentation/kdump/vmcoreinfo.txt ?

Thanks.
Lianbo
>  	VMCOREINFO_SYMBOL(node_online_map);
>  #ifdef CONFIG_MMU
>  	VMCOREINFO_SYMBOL_ARRAY(swapper_pg_dir);
>