Merge 5.4

Conflicts:
	Makefile
	include/linux/cpu.h
	include/linux/export.h
	kernel/cpu.c
	tools/Makefile

Signed-off-by: Octavian Purdila <tavi@cs.pub.ro>

scripts/link-vmlinux.sh

@@ -56,13 +56,19 @@ modpost_link()
 }
 
 # Link of vmlinux
-# ${1} - optional extra .o files
-# ${2} - output file
+# ${1} - output file
+# ${2}, ${3}, ... - optional extra .o files
 vmlinux_link()
 {
 	local lds="${objtree}/${KBUILD_LDS}"
+	local output=${1}
 	local objects
 
+	info LD ${output}
+
+	# skip output file argument
+	shift
+
 	if [ "${SRCARCH}" != "um" ]; then
 		objects="--whole-archive			\
 			${KBUILD_VMLINUX_OBJS}			\
@@ -70,9 +76,10 @@ vmlinux_link()
 			--start-group				\
 			${KBUILD_VMLINUX_LIBS}			\
 			--end-group				\
-			${1}"
+			${@}"
 
-		${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux} -o ${2}	\
+		${LD} ${KBUILD_LDFLAGS} ${LDFLAGS_vmlinux}	\
+			-o ${output}				\
 			-T ${lds} ${objects}
 	else
 		objects="-Wl,--whole-archive			\
@@ -81,9 +88,10 @@ vmlinux_link()
 			-Wl,--start-group			\
 			${KBUILD_VMLINUX_LIBS}			\
 			-Wl,--end-group				\
-			${1}"
+			${@}"
 
-		${CC} ${CFLAGS_vmlinux} -o ${2}			\
+		${CC} ${CFLAGS_vmlinux}				\
+			-o ${output}				\
 			-Wl,-T,${lds}				\
 			${objects}				\
 			-lutil -lrt -lpthread
@@ -92,23 +100,36 @@ vmlinux_link()
 }
 
 # generate .BTF typeinfo from DWARF debuginfo
+# ${1} - vmlinux image
+# ${2} - file to dump raw BTF data into
 gen_btf()
 {
-	local pahole_ver;
+	local pahole_ver
+	local bin_arch
 
 	if ! [ -x "$(command -v ${PAHOLE})" ]; then
 		info "BTF" "${1}: pahole (${PAHOLE}) is not available"
-		return 0
+		return 1
 	fi
 
 	pahole_ver=$(${PAHOLE} --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/')
 	if [ "${pahole_ver}" -lt "113" ]; then
 		info "BTF" "${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.13"
-		return 0
+		return 1
 	fi
 
-	info "BTF" ${1}
+	info "BTF" ${2}
+	vmlinux_link ${1}
 	LLVM_OBJCOPY=${OBJCOPY} ${PAHOLE} -J ${1}
+
+	# dump .BTF section into raw binary file to link with final vmlinux
+	bin_arch=$(LANG=C ${OBJDUMP} -f ${1} | grep architecture | \
+		cut -d, -f1 | cut -d' ' -f2)
+	bin_format=$(LANG=C ${OBJDUMP} -f ${1} | grep 'file format' | \
+		awk '{print $4}')
+	${OBJCOPY} --dump-section .BTF=.btf.vmlinux.bin ${1} 2>/dev/null
+	${OBJCOPY} -I binary -O ${bin_format} -B ${bin_arch} \
+		--rename-section .data=.BTF .btf.vmlinux.bin ${2}
 }
 
 # Create ${2} .o file with all symbols from the ${1} object file
@@ -146,6 +167,18 @@ kallsyms()
 	${CC} ${aflags} -c -o ${2} ${afile}
 }
 
+# Perform one step in kallsyms generation, including temporary linking of
+# vmlinux.
+kallsyms_step()
+{
+	kallsymso_prev=${kallsymso}
+	kallsymso=.tmp_kallsyms${1}.o
+	kallsyms_vmlinux=.tmp_vmlinux${1}
+
+	vmlinux_link ${kallsyms_vmlinux} "${kallsymso_prev}" ${btf_vmlinux_bin_o}
+	kallsyms ${kallsyms_vmlinux} ${kallsymso}
+}
+
 # Create map file with all symbols from ${1}
 # See mksymap for additional details
 mksysmap()
@@ -161,6 +194,7 @@ sortextable()
 # Delete output files in case of error
 cleanup()
 {
+	rm -f .btf.*
 	rm -f .tmp_System.map
 	rm -f .tmp_kallsyms*
 	rm -f .tmp_vmlinux*
@@ -225,7 +259,15 @@ info MODINFO modules.builtin.modinfo
 ${OBJCOPY} -j .modinfo -O binary vmlinux.o modules.builtin.modinfo
 fi
 
+btf_vmlinux_bin_o=""
+if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then
+	if gen_btf .tmp_vmlinux.btf .btf.vmlinux.bin.o ; then
+		btf_vmlinux_bin_o=.btf.vmlinux.bin.o
+	fi
+fi
+
 kallsymso=""
+kallsymso_prev=""
 kallsyms_vmlinux=""
 if [ -n "${CONFIG_KALLSYMS}" ]; then
 
@@ -252,37 +294,19 @@ if [ -n "${CONFIG_KALLSYMS}" ]; then
 	# a)  Verify that the System.map from vmlinux matches the map from
 	#     ${kallsymso}.
 
-	kallsymso=.tmp_kallsyms2.o
-	kallsyms_vmlinux=.tmp_vmlinux2
-
-	# step 1
-	vmlinux_link "" .tmp_vmlinux1
-	kallsyms .tmp_vmlinux1 .tmp_kallsyms1.o
-
-	# step 2
-	vmlinux_link .tmp_kallsyms1.o .tmp_vmlinux2
-	kallsyms .tmp_vmlinux2 .tmp_kallsyms2.o
+	kallsyms_step 1
+	kallsyms_step 2
 
 	# step 3
-	size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms1.o)
-	size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" .tmp_kallsyms2.o)
+	size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso_prev})
+	size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso})
 
 	if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then
-		kallsymso=.tmp_kallsyms3.o
-		kallsyms_vmlinux=.tmp_vmlinux3
-
-		vmlinux_link .tmp_kallsyms2.o .tmp_vmlinux3
-
-		kallsyms .tmp_vmlinux3 .tmp_kallsyms3.o
+		kallsyms_step 3
 	fi
 fi
 
-info LD vmlinux
-vmlinux_link "${kallsymso}" vmlinux
-
-if [ -n "${CONFIG_DEBUG_INFO_BTF}" ]; then
-	gen_btf vmlinux
-fi
+vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o}
 
 if [ -n "${CONFIG_BUILDTIME_EXTABLE_SORT}" ]; then
 	info SORTEX vmlinux