fix(driver/bpf): fixed bpf probe build on kernel >= 6.2

[FedeDP]

What type of PR is this?

/kind bug

Any specific area of the project related to this PR?

/area driver-bpf

Does this PR require a change in the driver versions?

What this PR does / why we need it:

Fixes build of old bpf probe on kernel >= 6.2.0.
See: torvalds/linux@f1a7941

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

fix(driver/bpf): fixed build of bpf probe on linux >= 6.2

[FedeDP]

Driverkit was finally able to build both kmod and ebpf drivers for 6.2.0:

DEBU 5clang -I./arch/x86/include -I./arch/x86/include/generated  -I./include -I./arch/x86/include/uapi -I./arch/x86/include/generated/uapi -I./include/uapi -I./include/generated/uapi -include ./include/linux/compiler-version.h -include ./include/linux/kconfig.h \
DEBU    -D__KERNEL__ -fmacro-prefix-map=./= \
DEBU     \
DEBU     \
DEBU    -D__KERNEL__ \
DEBU    -D__BPF_TRACING__ \
DEBU    -Wno-gnu-variable-sized-type-not-at-end \
DEBU    -Wno-address-of-packed-member \
DEBU    -fno-jump-tables \
DEBU    -fno-stack-protector \
DEBU    -Wno-tautological-compare \
DEBU    -O2 -g -emit-llvm -c /tmp/driver/bpf/probe.c -o /tmp/driver/bpf/probe.ll
DEBU {In file included from /tmp/driver/bpf/probe.c:16:
DEBU In file included from ./include/linux/sched.h:12:
DEBU In file included from ./arch/x86/include/asm/current.h:9:
DEBU In file included from ./include/linux/cache.h:6:
DEBU In file included from ./arch/x86/include/asm/cache.h:5:
DEBU In file included from ./include/linux/linkage.h:8:
DEBU In file included from ./arch/x86/include/asm/linkage.h:6:
DEBU ./arch/x86/include/asm/ibt.h:77:8: warning: 'nocf_check' attribute ignored; use -fcf-protection to enable the attribute [-Wignored-attributes]
DEBU extern __noendbr u64 ibt_save(void);
DEBU        ^
DEBU ./arch/x86/include/asm/ibt.h:32:34: note: expanded from macro '__noendbr'
DEBU ]#define __noendbr       __attribute__((nocf_check))
DEBU                                        ^
DEBU �./arch/x86/include/asm/ibt.h:78:8: warning: 'nocf_check' attribute ignored; use -fcf-protection to enable the attribute [-Wignored-attributes]
DEBU �extern __noendbr void ibt_restore(u64 save);
DEBU        ^
DEBU ./arch/x86/include/asm/ibt.h:32:34: note: expanded from macro '__noendbr'
DEBU ]#define __noendbr       __attribute__((nocf_check))
DEBU                                        ^
DEBU 2 warnings generated.
DEBU Qllc -march=bpf -filetype=obj -o /tmp/driver/bpf/probe.o /tmp/driver/bpf/probe.ll
DEBU )  MODPOST /tmp/driver/bpf/Module.symvers
DEBU )make[1]: Leaving directory '/tmp/kernel'
DEBU + ls -l probe.o
DEBU 4-rw-r--r-- 1 root root 4489856 Feb 22 14:16 probe.o
DEBU log pipe close                                error=EOF
INFO kernel module available                       path=/tmp/arch.ko
INFO eBPF probe available                          path=/tmp/arch.o

/cc @Molter73 @Andreagit97

[FedeDP]

/milestone next-driver

[FedeDP]

Rebased on top of master. 🙏 should work fine now!

[FedeDP]

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yay!

[Andreagit97]

We need to fix this also in the modern probe, I will try to find a solution without ifdefs.. In the meanwhile we can merge this to fix the CI
/approve

[Molter73]

/lgtm

[poiana]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Andreagit97, FedeDP, Molter73

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[FedeDP]

/milestone 4.0.1+driver