Re: [PATCH v4 0/4] Properly handle module_kobject creation

[Shyam Saini]

Hi Greg,

> On 2/27/25 19:49, Shyam Saini wrote:
> > Hi Everyone,
> > 
> > This patch series fixes handling of module_kobject creation.
> > A driver expect module_kset list populated with its corresponding
> > module_kobject to create its /sys/module/<built-in-module>/drivers
> > directory.
> > 
> > Since,
> > [1] commit 96a1a2412acb ("kernel/params.c: defer most of param_sysfs_init() to late_initcall time")
> > Call to populate module_kset list is deferred to save init time so that
> > external watchdog doesn't fireup on some boards and Linux can take
> > responsibility of feeding watchdog before it spuriously resets the
> > system. However, [1] this fix caused another issue i.e, consumers
> > of module_kset can't get related module_kobject during driver
> > initialisation and hence can't create their
> > /sys/module/<built-in-module>/drivers directory.
> > 
> > Consequently, [1] breaks user-space applications for eg: DPDK, which
> > expects /sys/module/vfio_pci/drivers/pci:vfio-pci/new_id to be present.
> > 
> > The second issue was reported and the [2] revert of [1] was
> > proposed. However, [2] the Revert doesn't address the original issue
> > reported in [1].
> > 
> > This patch series addresses both issues reported in [1] and [2].
> > 
> > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=96a1a2412acb
> > [2] https://lore.kernel.org/lkml/20250130225803.321004-1-shyamsaini@xxxxxxxxxxxxxxxxxxx/
> 
> This looks ok to me. I only think the Fixes: tag should have remained
> solely on the last patch in the series as that is the actual fix. I'll
> adjust it when picking up the patches.
> 
> I'm going to wait for a few days if others still would like to comment
> and then plan to queue this on modules-next.
> 
> @Greg, could I please get an Acked-by from you on the last patch in the
> series as this affects the code in the driver core?
>

do you have any feedback on last patch of this series?

Thanks,
Shyam