VC04: Address space mismatch - bulk_userdata

Describe the bug

Hello,

I am wondering if anyone here as visibility on [1]

It would help squashing the VC04 Sparse warnings for upsteram VC04 de-stage.

[1] : https://github.com/raspberrypi/linux/blob/rpi-6.6.y/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c#L543

Steps to reproduce the behaviour

Running Sparse on the mainline linux-staging branch, I get:

/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:335:26: warning: incorrect type in assignment (different address spaces)
/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:335:26:    expected void *[assigned] userdata
/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:335:26:    got void [noderef] __user *userdata
/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:553:47: warning: incorrect type in assignment (different address spaces)
/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:553:47:    expected void [noderef] __user *[addressable] [assigned] bulk_userdata
/home/uajain/src/kernel/mainline/media_tree/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c:553:47:    got void *bulk_userdata

On one of the location, there is clear FIXME about figuring out the correct address spaces.

Device (s)

Raspberry Pi 3 Mod. B+

System

Compile / static analysis on upstream branch:
https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git/log/?h=staging-testing

Logs

No response

Additional context

VC04 mainline de-staging

Start with drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c, especially the assignments at lines 335 and 553 and the referenced line 543. Review the existing FIXME about address spaces and reproduce the Sparse warnings on the staging-testing branch. Done means the bulk_userdata and userdata address-space warnings are resolved without introducing new Sparse warnings.