This is a note to let you know that I've just added the patch titled
KVM: arm64: nvhe: Fix build with profile optimization
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-arm64-nvhe-fix-build-with-profile-optimization.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From bde971a83bbff78561458ded236605a365411b87 Mon Sep 17 00:00:00 2001
From: Denis Nikitin <denik@xxxxxxxxxxxx>
Date: Fri, 14 Oct 2022 11:45:32 -0700
Subject: KVM: arm64: nvhe: Fix build with profile optimization
From: Denis Nikitin <denik@xxxxxxxxxxxx>
commit bde971a83bbff78561458ded236605a365411b87 upstream.
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>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221014184532.3153551-1-denik@xxxxxxxxxxxx
Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/kvm/hyp/nvhe/Makefile | 4 ++++
1 file changed, 4 insertions(+)
--- a/arch/arm64/kvm/hyp/nvhe/Makefile
+++ b/arch/arm64/kvm/hyp/nvhe/Makefile
@@ -83,6 +83,10 @@ 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
Patches currently in stable-queue which might be from denik@xxxxxxxxxxxx are
queue-5.15/kvm-arm64-nvhe-fix-build-with-profile-optimization.patch
