[PATCH v2 0/3] powerpc64/ftrace: fixes clang build issues

Venkat Rao Bagalkote venkat88 at linux.ibm.com
Fri Jan 30 17:18:58 AEDT 2026


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 <venkat88 at linux.ibm.com>




Regards,

Venkat.



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