On 27/01/26 2:19 pm, Hari Bathini wrote:
Support for -fpatchable-function-entry on ppc64le was added in Clang
with [1]. Faced a couple of issues while building the linux kernel
with Clang though. Patches 1 & 2 address those issues. The last patch
provides workaround to ensure, an open issue [2] in Clang with
-fpatchable-function-entry support, does not impact the linux
ftrace subsystem.
[1] https://github.com/llvm/llvm-project/pull/151569
[2] https://github.com/llvm/llvm-project/issues/163706
Hari Bathini (3):
powerpc64: make clang cross-build friendly
powerpc64/ftrace: fix OOL stub count with clang
powerpc64/ftrace: workaround clang recording GEP in
__patchable_function_entries
arch/powerpc/Kconfig | 4 +--
arch/powerpc/kernel/trace/ftrace.c | 26 ++++++++++++++++---
....sh => check-fpatchable-function-entry.sh} | 0
arch/powerpc/tools/ftrace-gen-ool-stubs.sh | 4 +--
4 files changed, 26 insertions(+), 8 deletions(-)
rename arch/powerpc/tools/{gcc-check-fpatchable-function-entry.sh =>
check-fpatchable-function-entry.sh} (100%)
Tested this patch series, and bulild is successful with both GCC and
clang23.x version.
KERNEL PARAMETER enabled:
CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY=y
CONFIG_PPC_FTRACE_OUT_OF_LINE=y
CONFIG_PPC_FTRACE_OUT_OF_LINE_NUM_RESERVE=32768
clang version 23.0.0git
Please add below tag for the series.
Tested-by: Venkat Rao Bagalkote <[email protected]>
Regards,
Venkat.
