Re: [REVIEW][PATCH 09/11] ipc/shm: Fix shmctl(..., IPC_STAT, ...) between pid namespaces.

[Nagarathnam Muthusamy]

On 03/28/2018 04:04 PM, ebiederm@xxxxxxxxxxxx wrote:
> NAGARATHNAM MUTHUSAMY <nagarathnam.muthusamy@xxxxxxxxxx> writes:
>
> > On 3/23/2018 2:33 PM, ebiederm@xxxxxxxxxxxx wrote:
> > > NAGARATHNAM MUTHUSAMY <nagarathnam.muthusamy@xxxxxxxxxx> writes:
> > >
> > > > Thanks!
> > > >
> > > > Reviewed-by: Nagarathnam Muthusamy <nagarathnam.muthusamy@xxxxxxxxxx>
> > > Does this look like it will address the issue you have been fighting
> > > with pids?
> > We do use IPC shared memory but it is a single large one, shared by multiple
> > levels. We are currently looking into using a similar solution based on file
> > locks.
> > When a new level is created, a file representing that level could be created in
> > a common path which could be locked by the init process of that level.
> > Parent levels could query the locking pid of that file to get the pid
> > translation
> > of the init process of the required level. Then it could open a file descriptor
> > and use the translate_pid API for further translations.
> Do you want to resend the translate_pid API with file descriptors as it
> was in the lwn article?  That I will apply.

Sure Eric! We are currently implementing and testing the file locks + FD 
based
approach, just to make sure it covers all the requirements. Will resend the
patch with FD based translate_pid API in few days.

Thanks,
Nagarathnam.
> Eric