Re: [PATCH v3 2/4] net: qrtr: Assign unique node id for MHI endpoints

Hi Juha-Matti,

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Well, in defense of Manivannan's patchset it currently works for PCI+AHB
setups better than the last version of that by Denis/Mihai/me (although 
I could easily fix that), and it may be simpler for userspace to
continue using nid than having to bind to an endpoint, which requires
more changes in userspace code.

The userspace just needs to know the nid.

and existing userspace? You can _NOT_ break existing userspace.

Don’t you need to re-write all existing QRTRIPC packets to actually even make this work?

Well, from what I understand this rewriting is the plan.

It is true that if someone has a single card, the nid changes, thus
maybe breaking userspace if the userspace has hardcoded nid.

But if someone has multiple cards, the breakage to userspace is less
with this patch, since userspace can keep on using the same code and
just change the nid, whereas with the endpoint_id patch, the userspace
needs code changes to bind to an endpoint.

the general rule for Linux is to _not_ break existing userspace.

Regards

Marcel