Re: [PATCH net-next v2 2/2] net: ipa: fix IPA validation

On Mon, Mar 22, 2021 at 08:17:59AM -0500, Alex Elder wrote:

On 3/22/21 1:40 AM, Leon Romanovsky wrote:

quoted

quoted

I'd like to suggest a plan so I can begin to make progress,
but do so in a way you/others think is satisfactory.
- I would first like to fix the existing bugs, namely that
   if IPA_VALIDATION is defined there are build errors, and
   that IPA_VALIDATION is not consistently used.  That is
   this 2-patch series.

The thing is that IPA_VALIDATION is not defined in the upstream kernel.
There is nothing to be fixed in netdev repository

quoted

- I assure you that my goal is to simplify the code that
   does this sort of checking.  So here are some specific
   things I can implement in the coming weeks toward that:
     - Anything that can be checked at build time, will
       be checked with BUILD_BUG_ON().

+1

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     - Anything checked with BUILD_BUG_ON() will*not*
       be conditional.  I.e. it won't be inside an
       #ifdef IPA_VALIDATION block.
     - I will review all remaining VALIDATION code (which
       can't--or can't always--be checked at build time),
       If it looks prudent to make it*always*  be checked,
       I will make it always be checked (not conditional
       on IPA_VALIDATION).

+1

quoted

The result should clearly separate checks that can be done
at build time from those that can't.

And with what's left (especially on that third sub-bullet)
I might have some better examples with which to argue
for something different.  Or I might just concede that
you were right all along.

I hope so.

I came up with a solution last night that I'm going to try
to implement.  I will still do the things I mention above.

The solution is to create a user space tool inside the
drivers/net/ipa directory that will link with the kernel
source files and will perform all the basic one-time checks
I want to make.

We are not talking about putting this tool in upstream repo, right?
If yes, please get buy-in from David/Jakub first.

Thanks