Re: [PATCH] Declare the file_operations struct as const

[Krish Jain]

Hi, could someone help with this? Still stuck. Maybe someone else has
some insight into this issue too? Or Greg or Bryan.

Thanks

On Mon, Aug 30, 2021 at 3:01 PM Krish Jain <krishjain02939@xxxxxxxxx> wrote:
>
> One sec this got even more confusing. I saw
> https://stackoverflow.com/questions/23184181/error-while-running-make-install-include-generated-autoconf-h-or-include-confi
> and it says
>
> -------
> You are including the V=1 which causes Make to show the commands as
> they're being run. From the looks of it, you're not actually seeing
> the error itself, but you're seeing the test that it's running to
> check if those files exist:
>
> test -e include/generated/autoconf.h -a -e include/config/auto.conf ||
> ( \ ... echo error messages here ... \ )
>
> That test is being run, and if it fails, it would echo those messages
> to standard error, which it's not. If your module isn't building it's
> probably due to some other issue.
> ------
>
> So where is it going all wrong? Messing up the file ashmem.c does not
> print the errors.
>
>
> Best Regards
>
> On Mon, Aug 30, 2021 at 2:40 PM Krish Jain <krishjain02939@xxxxxxxxx> wrote:
> >
> > Hi.
> >
> > https://pastebin.com/NuvqMUWu is the link to the .config file.
> > The error I get is https://imgur.com/gkwh7Sb .
> >
> >
> > Best Regards
> >
> >
> > On Mon, Aug 30, 2021 at 12:11 AM Krish Jain <krishjain02939@xxxxxxxxx> wrote:
> > >
> > > On Sun, Aug 29, 2021 at 11:00 PM Bryan Brattlof <hello@xxxxxxxxxxxxxxxxx> wrote:
> > > >
> > > > On this day, August 29, 2021, thus sayeth Krish Jain:
> > > > > Keeping you updated. Small win. The "Symbol version dump
> > > > > "Module.symvers" is missing. " error disappeared. Now I still don't
> > > > > know why
> > > > >
> > > >
> > > > Whoop! Any win, no matter their size, always feel great. I ran around
> > > > the house yesterday after cross compiling DOOM! for an armel chip. It's
> > > > that "win" feeling you get that keeps me involved.
> > > >
> > > > It is important that you find out why though. What is the importance to
> > > > having Module.symvers? and why is it a WARNING and not an ERROR?
> > >
> > >  When a module is loaded/used, the values contained in the kernel are
> > > compared with similar values in the module; if they are not equal, the
> > > kernel refuses to load the module. I don't need it in my case.
> > >
> > > > What would happen if we didn't have the proper symbols when compiling or
> > > > installing this driver?
> > > > How and what generates the Module.symvers file when we *do* need it?
> > >
> > > The kernel would refuse to load the module.
> > >
> > >
> > >
> > >
> > >
> > > > How can we turn this warning off when we don't need it?
> > > >
> > > > This is covered in chapter "6. Module Versioning"
> > > >
> > > >   https://www.kernel.org/doc/html/latest/kbuild/modules.html
> > > >
> > > > >
> > > > > ERROR: Kernel configuration is invalid."; \
> > > > > echo >&2 "         include/generated/autoconf.h or
> > > > > include/config/auto.conf are missing.";\
> > > > > echo >&2 "         Run 'make oldconfig && make prepare' on kernel src
> > > > > to fix it."; \
> > > > >
> > > > >
> > > > > is still present.
> > > > >
> > > > > How can I fix this?
> > > > >
> > > >
> > > > Are there any other 'make *config' options we could try?
> > >
> > > Yes, like main menuconfig. I tried it but it still doesn't work.
> > >
> > > > What does 'make prepare' even do?
> > >
> > >
> > > Prepares for different architectures etc.
> > >
> > >
> > > > Why do we even need a configuration file?
> > > >
> > > >   https://www.kernel.org/doc/html/latest/kbuild/kconfig.html
> > > >
> > > > >
> > > > > Best Regards
> > > > >
> > > > > On Sun, Aug 29, 2021 at 8:28 PM Krish Jain <krishjain02939@xxxxxxxxx> wrote:
> > > > > >
> > > > > > Basically it says "you must have a prebuilt kernel available that
> > > > > > contains the configuration and header files used in the build." Since
> > > > > > for the staging kernel  "make oldconfig" asked me for  more
> > > > > > configurations apart from my old configuration file (as it reads the
> > > > > > existing .config file that was used for an old kernel and prompts the
> > > > > > user for options in the current kernel source that are not found in
> > > > > > the file) . So I *don't* currently have a prebuilt kernel that
> > > > > > contains all the configuration in my staging kernel's .config file. So
> > > > > > do I have to build the kernel once before I can just build the module
> > > > > > with "make CCFLAGS=-Werror W=1 M=drivers/staging/android" ?
> > > > > >
> > > >
> > > > What do all these other configuration settings turn on and off anyway?
> > > >
> > > > Do we really need CONFIG_INFINIBAND turned on if we're working in the
> > > > drivers/staging tree of the kernel?
> > >
> > >
> > > No, we don't. I removed it.
> > >
> > > > What would we gain from having a compiled kernel if we want to test a
> > > > single staging driver?
> > >
> > > No need to compile the entire kernel I guess for my use case. But
> > > after all this reading :( I still don't get why " sudo make
> > > CCFLAGS=-Werror W=1 M=drivers/staging/android/  V=1" worked for you
> > > but not for me. I still get the following errors
> > >
> > >
> > > test -e include/generated/autoconf.h -a -e include/config/auto.conf || ( \
> > > echo >&2; \
> > > echo >&2 "  ERROR: Kernel configuration is invalid."; \
> > > echo >&2 "         include/generated/autoconf.h or
> > > include/config/auto.conf are missing.";\
> > > echo >&2 "         Run 'make oldconfig && make prepare' on kernel src
> > > to fix it."; \
> > > echo >&2 ; \
> > > /bin/false)
> > > .....
> > >
> > >
> > > How can I fix this?
> > >
> > >
> > >
> > >
> > > > If you found what Module.symvers does, you should know this.
> > > >
> > > > > > > >
> > > > > > > > Again, do not allow others to rob you of learning how to solve these
> > > > > > > > issues yourself. I *strongly* encourage you to familiarize yourself with
> > > > > > > > the Kernel Build System in the Documentation.
> > > > > > > >
> > > > > > > >   https://www.kernel.org/doc/html/latest/kbuild/modules.html
> > > > > > > >
> > > > > > > > Specifically the first paragraph of "2. How to Build External Modules"
> > > > > > > >
> > > > > > > > It may seem like a lot for such a simple issue but it *is* worth it.
> > > > > > > > ~Bryan
> > > > > > > >
> > > > > > >
> > > > > > > That section says
> > > > > > >
> > > > > > >
> > > > > > > "To build external modules, *you must have a prebuilt kernel
> > > > > > > available* that contains the configuration and header files used in
> > > > > > > the build. Also, the kernel must have been built with modules enabled.
> > > > > > > If you are using a distribution kernel, there will be a package for
> > > > > > > the kernel you are running provided by your distribution.
> > > > > > >
> > > > > > > An alternative is to use the “make” target “modules_prepare.” This
> > > > > > > will make sure the kernel contains the information required. The
> > > > > > > target exists solely as a simple way to prepare a kernel source tree
> > > > > > > for building external modules.
> > > > > > >
> > > > > > > NOTE: “modules_prepare” will not build Module.symvers even if
> > > > > > > CONFIG_MODVERSIONS is set; therefore, *a full kernel build needs to be
> > > > > > > executed to make module versioning work.*"
> > > > > > >
> > > > > > > So I am just trying to confirm with you whether I have to first build
> > > > > > > the kernel with like "make" or not? As you can imagine my hardware
> > > > > > > takes *very* long to build a kernel as I did in my last attempt so I
> > > > > > > am asking whether it is needed. Hope you understand.
> > > > > > >
> > > >
> > > > I understand. Though I still don't wish to rob you of this opportunity.
> > > >
> > > > Your ability to come up with these questions and answer them yourself is
> > > > what will make you a better programmer and developer.
> > > >
> > > > Don't get me wrong. Greg knows all too well the garbage I can shovel his
> > > > way. It's not about knowing the answer. It about knowing how to find the
> > > > answer yourself.
> > > >
> > > > ~Bryan
> > > >