On Redhat 9.4/9.5 make ksmbd fails due to missing genhd.h for vfs.c

[besterino]

Error:

make[1]: Entering directory '/usr/src/kernels/5.14.0-503.14.1.el9_5.x86_64'
CC [M] /home/test/ksmbd/unicode.o
CC [M] /home/test/ksmbd/auth.o
CC [M] /home/test/ksmbd/vfs.o
/home/test/ksmbd/vfs.c:19:10: fatal error: linux/genhd.h: No such file or directory
19 | #include <linux/genhd.h>
| ^~~~~~~~~~~~~~~
compilation terminated.
make[2]: *** [scripts/Makefile.build:249: /home/bestie/ksmbd/vfs.o] Error 1
make[1]: *** [Makefile:1944: /home/bestie/ksmbd] Error 2
make[1]: Leaving directory '/usr/src/kernels/5.14.0-503.14.1.el9_5.x86_64'
make: *** [Makefile:47: all] Error 2

Seems genhd.h is no longer included but still expected for this particular kernel?

uname -r:
5.14.0-503.14.1.el9_5.x86_64

[hireworksltd]

Looks likes genhd.h was removed in 5.19.8 (though not sure why you're seeing this in 5.14, guess RH specific)

see: https://lore.kernel.org/all/9bb3f4c6-4e21-e1d7-b4e1-f65d273cd3f8@nvidia.com/t/

try changing it for <linux/blkdev.h>

Cheers,
Jon

[besterino]

I tried blkdev.h instead of genhd.h, but that threw a lot of (other) errors, so that is not really a fix.

[capnbb]

I'm sure your busy, but forgive the bump as a buildable ksmbd kernel module on a RHEL clone would be very, very useful:

We see exactly the same problem on Alma 9.5 with kernel 5.14.0-503.21.1.el9_5.x86_64

likewise changing genhd.h for blkdev.h in vfs.c threw lots of other errors.

any work around greatly appreciated.

Jake

[namjaejeon]

@capnbb I have removed genhd header in #master branch. Please check it.

[capnbb]

Thank you so much @namjaejeon, but I'm sorry to say this still doesn't fix our build issue.

I've given details next to your Commit 4c27c3b

4c27c3b

again, many thanks

Jake

[namjaejeon]

Although kernel version of Redhat 9.4/9.5 is not 5.14 kernel, they didn't increase their kernel version.
They updated kernel source without changing kernel version.

[capnbb]

The mismatch is due to Redhat backporting features and fixes to the kernel, so it ends up as a hybrid that never exactly matches the official kernel. The backport kernels work for lots of dkms kernel modules, but breaks others…😟

I'll try enabling the elrepo-kernel, as this gives us access to standard kernels which ksmbd should build against...

Thanks again

[capnbb]

Quick update, the current LTS kernel for Alma 9.5 (kernel-lt-6.1.128-1.el9 ) doesn't build ksmbd

make gives an "error: redefinition of ‘is_dot_dotdot’"

However, commenting the offending section out of vfs.c allows the build to complete:

diff vfs.c.orig vfs.c
2663,2667c2663,2667
< static inline bool is_dot_dotdot(const char *name, size_t len)
< {
< return len && unlikely(name[0] == '.') &&
< (len == 1 || (len == 2 && name[1] == '.'));
< }

//static inline bool is_dot_dotdot(const char *name, size_t len)
//{
// return len && unlikely(name[0] == '.') &&
// (len == 1 || (len == 2 && name[1] == '.'));
//}