On Tue, Sep 23, 2025 at 9:31 AM Jan Stancek <[email protected]> wrote: > > We've been observing rare non-deterministic kconfig failures during > olddefconfig, where ARCH_USING_PATCHABLE_FUNCTION_ENTRY was getting > disabled and with it number of other config options that depend on it. > > The reason is that gcc-check-fpatchable-function-entry.sh can fail > if `grep -q` (or scripts/dummy-tools/gcc) is fast enough to exit while > there is still someone writing on other side of pipe. `pipefail` > propagates that error up to kconfig. > > This can be seen for example with: > # (set -e; set -o pipefail; yes | grep -q y); echo $? > 141 > > or by running the actual check script in loop extensively: > ----------------------------- 8< ------------------------------- > function kconfig() > { > for i in `seq 1 100`; do > arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh \ > ./scripts/dummy-tools/gcc -mlittle-endian \ > || { echo "Oops"; exit 1; } > done > } > > for ((i=0; i<$(nproc); i++)); do kconfig & done > wait; echo "Done" > ----------------------------- >8 ------------------------------- > > Fixes: 0f71dcfb4aef ("powerpc/ftrace: Add support for > -fpatchable-function-entry") > Fixes: b71c9ffb1405 ("powerpc: Add arch/powerpc/tools directory") > Reported-by: Joe Lawrence <[email protected]> > Acked-by: Joe Lawrence <[email protected]> > Signed-off-by: Jan Stancek <[email protected]> > --- > arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh | 1 - > arch/powerpc/tools/gcc-check-mprofile-kernel.sh | 1 - > 2 files changed, 2 deletions(-) > > diff --git a/arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh > b/arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh > index 06706903503b..baed467a016b 100755 > --- a/arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh > +++ b/arch/powerpc/tools/gcc-check-fpatchable-function-entry.sh > @@ -2,7 +2,6 @@ > # SPDX-License-Identifier: GPL-2.0 > > set -e > -set -o pipefail > > # To debug, uncomment the following line > # set -x > diff --git a/arch/powerpc/tools/gcc-check-mprofile-kernel.sh > b/arch/powerpc/tools/gcc-check-mprofile-kernel.sh > index 73e331e7660e..6193b0ed0c77 100755 > --- a/arch/powerpc/tools/gcc-check-mprofile-kernel.sh > +++ b/arch/powerpc/tools/gcc-check-mprofile-kernel.sh > @@ -2,7 +2,6 @@ > # SPDX-License-Identifier: GPL-2.0 > > set -e > -set -o pipefail > > # To debug, uncomment the following line > # set -x > -- > 2.47.1
Would love to see this picked up, it fixes a problem we have run into with our CI. Tested-by: Justin M. Forbes <[email protected]>
