From:   "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
To:     Khadija Kamran <kamrankhadijadj@gmail.com>
Cc:     Nathan Chancellor <nathan@kernel.org>,
        Alison Schofield <alison.schofield@intel.com>,
        outreachy@lists.linux.dev, llvm@lists.linux.dev,
        oe-kbuild-all@lists.linux.dev,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: axis-fifo: initialize timeouts in probe only
Date:   Tue, 14 Mar 2023 20:07:07 +0100
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In-Reply-To: <ZBCPMVFvjodeUbGF@aschofie-mobl2>
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 <20230314144207.GA4106922@dev-arch.thelio-3990X>
 <ZBCPMVFvjodeUbGF@aschofie-mobl2>
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On marted=EC 14 marzo 2023 16:13:53 CET Alison Schofield wrote:
> On Tue, Mar 14, 2023 at 07:42:07AM -0700, Nathan Chancellor wrote:
> > Hi Khadija,
> >=20
> > On Tue, Mar 14, 2023 at 07:08:31PM +0500, Khadija Kamran wrote:
> > > On Tue, Mar 14, 2023 at 11:45:51AM +0800, kernel test robot wrote:
> > > >
> > > > [...]
> > >=20
> > > Hi everyone!
> > > Kindly let me know if I should look into these warnings.
> > > Thank you!
> >=20
> > You should always avoid introducing new warnings whenever possible. In
> > this case, it appears that read_timeout and write_timeout should be
> > changed from 'int' to 'long' to account for the fact that
> > MAX_SCHEDULE_TIMEOUT is being assigned to it directly now, versus being
> > passed as a parameter to wait_event_interruptible_timeout(), which
> > assigned it to 'long' anyways.
> >=20
> > If you have any other questions or need further help, let me know :)
> >=20
> > Cheers,
> > Nathan
>=20
> Hi Khadija,
>=20
> Echoing Nathan's feedback - yes, you need to correct these.
>=20
> Do you see these warnings when you compiled?  If yes, then your path to
> fixing them is easier. Make sure it recompiles with no warnings.
>=20
> If you don't see these warnings, then you need to follow the steps to
> reproduce in the lkp email. You have to be able to 'see the warning'
> make a change and 'see it go away'.
>=20
> Alison
>=20

Hi Khadija,

I would suggest trying to recompile using "make W=3D1 -j...". Not sure if y=
ou'll=20
see the warnings (depends on your compiler, version and target architecture=
).=20
However, it's worth a try as it may save you the time it takes to go throug=
h=20
the steps for reproduction.

Anyway, as Nathan said, that warning is triggered by assigning 'long' to 'i=
nt'=20
(i.e., "MAX_SCHEDULE_TIMEOUT" is cast to 'long', while the types of=20
"read_timeout" and "write_timeout " are both 'int'). Obviously, these kinds=
 of =20
assignments overflow wherever the representation of type 'long' uses more b=
its=20
than the type 'int'.

That implies that you should try to understand where the module's parameter=
s=20
are defined and how to work with the related macros.

I hope it helps.

=46abio

P.S.: If you don't know yet what to do, take a look at the following docume=
nt:
https://sysprog21.github.io/lkmpg/ (The Linux Kernel Module Programming=20
Guide).
  =20