After commit da5fb18225b4 ("bpf: Support pre-2.25-binutils objcopy for
vmlinux BTF"), having CONFIG_DEBUG_INFO_BTF enabled but lacking a valid
copy of pahole results in a kernel that will fully compile but fail to
link. The user then has to either install pahole or disable
CONFIG_DEBUG_INFO_BTF and rebuild the kernel but only after their build
has failed, which could have been a significant amount of time depending
on the hardware.
Avoid a poor user experience and require pahole to be installed with an
appropriate version to select and use CONFIG_DEBUG_INFO_BTF, which is
standard for options that require a specific tools version.
Suggested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
---
MAINTAINERS | 1 +
init/Kconfig | 4 ++++
lib/Kconfig.debug | 6 ++----
scripts/link-vmlinux.sh | 13 -------------
scripts/pahole-version.sh | 16 ++++++++++++++++
5 files changed, 23 insertions(+), 17 deletions(-)
create mode 100755 scripts/pahole-version.sh
diff --git a/MAINTAINERS b/MAINTAINERS
index b8db7637263a..6f6e24285a94 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3282,6 +3282,7 @@ F: net/core/filter.c
F: net/sched/act_bpf.c
F: net/sched/cls_bpf.c
F: samples/bpf/
+F: scripts/pahole-version.sh
F: tools/bpf/
F: tools/lib/bpf/
F: tools/testing/selftests/bpf/
diff --git a/init/Kconfig b/init/Kconfig
index b77c60f8b963..872c61b5d204 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -74,6 +74,10 @@ config TOOLS_SUPPORT_RELR
config CC_HAS_ASM_INLINE
def_bool $(success,echo 'void foo(void) { asm inline (""); }' | $(CC) -x c - -c -o /dev/null)
+config PAHOLE_VERSION
+ int
+ default $(shell,$(srctree)/scripts/pahole-version.sh $(PAHOLE))
+
config CONSTRUCTORS
bool
depends on !UML
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 7937265ef879..70c446af9664 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -267,6 +267,7 @@ config DEBUG_INFO_DWARF4
config DEBUG_INFO_BTF
bool "Generate BTF typeinfo"
+ depends on PAHOLE_VERSION >= 116
depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED
depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST
help
@@ -274,12 +275,9 @@ config DEBUG_INFO_BTF
Turning this on expects presence of pahole tool, which will convert
DWARF type info into equivalent deduplicated BTF type info.
-config PAHOLE_HAS_SPLIT_BTF
- def_bool $(success, test `$(PAHOLE) --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'` -ge "119")
-
config DEBUG_INFO_BTF_MODULES
def_bool y
- depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
+ depends on DEBUG_INFO_BTF && MODULES && PAHOLE_VERSION >= 119
help
Generate compact split BTF type information for kernel modules.
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index 6eded325c837..eef40fa9485d 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -139,19 +139,6 @@ vmlinux_link()
# ${2} - file to dump raw BTF data into
gen_btf()
{
- local pahole_ver
-
- if ! [ -x "$(command -v ${PAHOLE})" ]; then
- echo >&2 "BTF: ${1}: pahole (${PAHOLE}) is not available"
- return 1
- fi
-
- pahole_ver=$(${PAHOLE} --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/')
- if [ "${pahole_ver}" -lt "116" ]; then
- echo >&2 "BTF: ${1}: pahole version $(${PAHOLE} --version) is too old, need at least v1.16"
- return 1
- fi
-
vmlinux_link ${1}
info "BTF" ${2}
diff --git a/scripts/pahole-version.sh b/scripts/pahole-version.sh
new file mode 100755
index 000000000000..6de6f734a345
--- /dev/null
+++ b/scripts/pahole-version.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Usage: $ ./scripts/pahole-version.sh pahole
+#
+# Print the pahole version as a three digit string
+# such as `119' for pahole v1.19 etc.
+
+pahole="$*"
+
+if ! [ -x "$(command -v $pahole)" ]; then
+ echo 0
+ exit 1
+fi
+
+$pahole --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'
base-commit: e22d7f05e445165e58feddb4e40cc9c0f94453bc
--
2.30.0
