[OS-BUILD PATCH] spec: use jsut-built bpftool for vmlinux.h generation

[Artem Savkov (via Email Bridge)]

From: Yauheni Kaliuta

spec: use jsut-built bpftool for vmlinux.h generation

Bugzilla: http://bugzilla.redhat.com/2120968
Upstream status: RHEL-only

With the latest toolchain update build fails due to libbpf missing
btf enum64 support. 5.19 update contains libbpf update but the spec
uses buildroot's (old) bpftool.

Switch to use the just-built bpftool.

The snippet cannot be moved below bpftool build since vmlinux.h is
needed to build_tools.

Credits to Felix Maurer

Signed-off-by: Yauheni Kaliuta

diff --git a/redhat/kernel.spec.template b/redhat/kernel.spec.template
index blahblah..blahblah 100644
--- a/redhat/kernel.spec.template
+++ b/redhat/kernel.spec.template
@@ -666,9 +666,6 @@ BuildRequires: kernel-rpm-macros
 # glibc-static is required for a consistent build environment (specifically
 # CONFIG_CC_CAN_LINK_STATIC=y).
 BuildRequires: glibc-static
-%ifnarch %{nobuildarches} noarch
-BuildRequires: bpftool
-%endif
 %if %{with_headers}
 BuildRequires: rsync
 %endif
@@ -2610,7 +2607,9 @@ BuildKernel() {
     # Generate vmlinux.h and put it to kernel-devel path
     # zfcpdump build does not have btf anymore
     if [ "$Variant" != "zfcpdump" ]; then
-        bpftool btf dump file vmlinux format c > $RPM_BUILD_ROOT/$DevelDir/vmlinux.h
+        # Build the bootstrap bpftool to generate vmlinux.h
+        make -C tools/bpf/bpftool bootstrap
+        tools/bpf/bpftool/bootstrap/bpftool btf dump file vmlinux format c > $RPM_BUILD_ROOT/$DevelDir/vmlinux.h
     fi

# prune junk from kernel-devel

--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2884