Bug 2332597

1. Please describe the problem:

When attempting to create systemtap instrumentation which builds an out-of-tree kernel modules on any kernel-6.13.0-0.rc1.20241202gite70140ba0d2b.14.fc42 or later the build fails.



2. What is the Version-Release number of the kernel:

kernel-6.13.0-0.rc1.20241202gite70140ba0d2b.14.fc42


3. Did it work previously in Fedora? If so, what kernel version did the issue
   *first* appear?  Old kernels are available for download at
   https://koji.fedoraproject.org/koji/packageinfo?packageID=8 :

Yes, this worked on kernel-6.13.0-0.rc0.20241126git7eef7e306d3c.10.fc42.  There appears to be an issue in git commit 693d79c092c19da7fe6c94cd76c1ee36de6b8b2a causing the out of tree kernel module build issue.

4. Can you reproduce this issue? If so, please provide the steps to reproduce
   the issue below:

sudo dnf install "systemtap*"
sudo stap-prep
stap -p4 -ke 'probe begin {printf("hello\n"); exit()}'

Rather than generating a kernel module, we get an error message like the following:

/usr/src/kernels/6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64/scripts/Makefile.build:367: warning: overriding recipe for target 'modules.order'
/usr/src/kernels/6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64/Makefile:1960: warning: ignoring old recipe for target 'modules.order'
/usr/src/kernels/6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64/Makefile:30: /tmp/stapygcc35/Makefile.rhelver: No such file or directory
make[3]: *** No rule to make target '/tmp/stapygcc35/Makefile.rhelver'.  Stop.
make[2]: *** [/usr/src/kernels/6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64/Makefile:2035: .] Error 2
make[1]: *** [/usr/src/kernels/6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64/Makefile:395: __build_one_by_one] Error 2
make: *** [Makefile:263: __sub-make] Error 2
WARNING: kbuild exited with status: 2
Pass 4: compilation failed.  [man error::pass4]
Kernel version 6.13.0 is outside tested range 3.10 ... 6.12-rc
Keeping temporary directory "/tmp/stapygcc35"



5. Does this problem occur with the latest Rawhide kernel? To install the
   Rawhide kernel, run ``sudo dnf install fedora-repos-rawhide`` followed by
   ``sudo dnf update --enablerepo=rawhide kernel``:

The problem still exists with the most recent kernels, 
kernel-6.13.0-0.rc2.20241211gitf92f4749861b.24.fc42.x86_64.

The problem appears to be introduced by git commit 693d79c092c19da7fe6c94cd76c1ee36de6b8b2a which adds the following to patch-6.13-redhat.patch:

diff --git a/Makefile b/Makefile
index 64c594bd7ad0..0fc23f9db9ca 100644
--- a/Makefile
+++ b/Makefile
@@ -22,6 +22,18 @@ $(if $(filter __%, $(MAKECMDGOALS)), \
 PHONY := __all
 __all:
 
+# Set RHEL variables
+# Note that this ifdef'ery is required to handle when building with
+# the O= mechanism (relocate the object file results) due to upstream
+# commit 67d7c302 which broke our RHEL include file
+ifneq ($(realpath source),)
+include $(realpath source)/Makefile.rhelver
+else
+ifneq ($(realpath Makefile.rhelver),)
+include Makefile.rhelver
+endif
+endif
+

6. Are you running any modules that not shipped with directly Fedora's kernel?:

No, this is a problem with the fedora kernel-devel rpm.


7. Please attach the kernel logs. You can get the complete kernel log
   for a boot with ``journalctl --no-hostname -k > dmesg.txt``. If the
   issue occurred on a previous boot, use the journalctl ``-b`` flag.

Reproducible: Always