Re: [PATCH v2 net 0/5] net: ipa: minor bug fixes

[Alex Elder]

On 10/29/20 11:11 AM, Jakub Kicinski wrote:
> On Wed, 28 Oct 2020 14:41:43 -0500 Alex Elder wrote:
> > This series fixes several bugs.  They are minor, in that the code
> > currently works on supported platforms even without these patches
> > applied, but they're bugs nevertheless and should be fixed.
>
> By which you mean "it seems to work just fine most of the time" or "the
> current code does not exercise this paths/functionally these bugs don't
> matter for current platforms".

The latter, although for patch 3 I'm not 100% sure.

Case by case:
Patch 1:
  It works.  I inquired what the consequence of passing this
  wrong buffer pointer was, and for the way we are using IPA
  it seems it's fine--the memory pointer we were assigning is
  not used, so it's OK.  But we're assigning the wrong pointer.
Patch 2:
  It works.  Even though the bit field is 1 bit wide (not two)
  we never actually write a value greater than 1, so we don't
  cause a problem.  But the definition is incorrect.
Patch 3:
  It works, but on the SDM845 we should be assigning the endpoints
  to use resource group 1 (they are 0 by default).  The way we
  currently use this upstream we don't have other endpoints
  competing for resources, so I think this is fine.  SC7180 we
  will assign endpoints to resource group 0, which is the default.
Patch 4:
  It works.  This is like patch 2; we define the number of these
  things incorrectly, but the way we currently use them we never
  exceed the limit in a broken way.
Patch 5:
  It works.  The maximum number of supported groups is even,
  and if a (smaller) odd number are used the remainder are
  programmed with 0, which is appropriate for undefined
  fields.

If you have any concerns about back-porting these fixes I
think I'm comfortable posting them for net-next instead.
I debated that before sending them out.  Please request that
if it's what you think would be best.

					-Alex