Re: [RFC PATCH 1/2] Set TOPDIR_PATH and generate its sha256sum at run time

[Chuck Lever <cel@kernel.org>]

On 8/29/25 7:19 AM, Luis Chamberlain wrote:
> On Thu, Aug 28, 2025 at 04:28:26PM -0400, Chuck Lever wrote:
>> From: Chuck Lever <chuck.lever@oracle.com>
>>
>> Commit 42d27579a9d0 ("guestfs: enhance ssh config choice") added a
>> uniquifier to the name of the ssh config to avoid multiple kdevops
>> runs clobbering each other's ssh config entries. It uses the TOPDIR
>> pathname set in the current .config to benefit from the nice
>> convenience of generating an Ansible extra_var using "output yaml".
>>
>> However, if the same user generates all her .configs (that will be
>> run by other users under automation) while in the same directory
>> (say, if they are different branches in the same git repository),
>> the TOPDIR pathname and thus the sha256sum of that pathname will be
>> exactly the same in all of those .config files, allowing the path
>> names of the ephemeral ssh configs to collide.
> 
> Both paragraphs above took me quite a bit of time to grasp, I think
> it was the parenthesis, as they make me try to switch contexts. So
> I think the explanation of the issue can be simplified. I *think*
> that the issue your are describing is essentially that we currently
> cannot support sharing .config to other users because TOPDIR_PATH
> expects the same path to be used. Would that be a summary of the
> issue?

I struggled with writing it. I wanted to capture my use case as the
rationale for the change. I'll try to integrate your suggestion.


>> The TOPDIR and its checksum need to be generated not by "make
>> menuconfig" but rather by "make" in order that .config files (as
>> saved in defconfigs/) can be truly portable.
> 
> This is nice.
> 
>> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
>> ---
>>  Kconfig                    | 15 ---------------
>>  Makefile                   |  4 ++++
>>  scripts/gen-hosts.Makefile |  1 +
>>  scripts/ssh.Makefile       |  4 ++--
>>  4 files changed, 7 insertions(+), 17 deletions(-)
>>
>> diff --git a/Kconfig b/Kconfig
>> index 3f2bc8cf019a..948befbce4de 100644
>> --- a/Kconfig
>> +++ b/Kconfig
>> @@ -5,21 +5,6 @@
>>  
>>  mainmenu "$(PROJECT) $(PROJECTRELEASE)"
>>  
>> -config TOPDIR_PATH
>> -	string
>> -	output yaml
>> -	default $(shell, echo $TOPDIR_PATH)
>> -
>> -config TOPDIR_PATH_HAS_SHA256SUM
>> -	bool
>> -	output yaml
>> -	default y
>> -
>> -config TOPDIR_PATH_SHA256SUM
>> -	string
>> -	output yaml
>> -	default $(shell, ./scripts/compute_sha256sum.sh $(TOPDIR_PATH))
>> -
>>  config HAVE_KDEVOPS_CUSTOM_DEFAULTS
>>  	bool
>>  	default n
>> diff --git a/Makefile b/Makefile
>> index 8755577e4d85..b6fdbe67fc07 100644
>> --- a/Makefile
>> +++ b/Makefile
>> @@ -19,6 +19,8 @@ export KDEVOPS_NODES :=
>>  export PYTHONUNBUFFERED=1
>>  export TOPDIR=./
>>  export TOPDIR_PATH = $(shell readlink -f $(TOPDIR))
>> +export TOPDIR_PATH_HAS_SHA256SUM=y
> 
> We added this a long time ago, to remain compatible with users who
> may git pull to the latest kdevops which didn't yet have the symbol
> TOPDIR_PATH_HAS_SHA256SUM.
> 
> So I think a prep patch to just remove TOPDIR_PATH_HAS_SHA256SUM now
> make sense.

Ha! I had a sentence in the patch description suggesting removal of
HAS_SHA256SUM, but decided to keep things simple and took it out.


> Otherwise this is looking nice.
> 
>   Luis


-- 
Chuck Lever