Kernel build with clang and KCFLAGS=-fprofile-sample-use=<profile> fails with: error: arch/arm64/kvm/hyp/nvhe/kvm_nvhe.tmp.o: Unexpected SHT_REL section ".rel.llvm.call-graph-profile" Starting from 13.0.0 llvm can generate SHT_REL section, see https://reviews.llvm.org/rGca3bdb57fa1ac98b711a735de048c12b5fdd8086. gen-hyprel does not support SHT_REL relocation section. Filter out profile use flags to fix the build with profile optimization. Signed-off-by: Denis Nikitin <denik@xxxxxxxxxxxx> --- V2 -> V3: Filter out the profile-use flags. V1 -> V2: Remove the relocation instead of disabling the profile-use flags. --- arch/arm64/kvm/hyp/nvhe/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index b5c5119c7396..16c6abdda494 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -89,6 +89,10 @@ quiet_cmd_hypcopy = HYPCOPY $@ # Remove ftrace, Shadow Call Stack, and CFI CFLAGS. # This is equivalent to the 'notrace', '__noscs', and '__nocfi' annotations. KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI), $(KBUILD_CFLAGS)) +# Starting from 13.0.0 llvm emits SHT_REL section '.llvm.call-graph-profile' +# when profile optimization is applied. gen-hyprel does not support SHT_REL and +# causes a build failure. Remove profile optimization flags. +KBUILD_CFLAGS := $(filter-out -fprofile-sample-use=% -fprofile-use=%, $(KBUILD_CFLAGS)) # KVM nVHE code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may -- 2.38.0.413.g74048e4d9e-goog _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
