On Sat, Sep 19, 2026 at 01:06:06AM +0000, Zhouyi Zhou wrote:
> Discovered in the Open Source Lab of Oregon State University when running
> torture.sh on a ppc64le VM. Two bugs were exposed:
>
> 1. The kvm-transform.sh call hard-coded "bzImage" as the kernel image
> name. On ppc64, the boot image is vmlinux, not bzImage, so the
> re-run failed to find the image. Fix this by extracting the QEMU
> binary from the qemu-cmd file and passing it to identify_boot_image()
> to obtain the correct architecture-specific image name, the same way
> kvm.sh already does.
>
> 2. The rm -f invocation on re-run listed vmlinux among the files to
> delete. On ppc64 vmlinux is the boot image, so deleting it broke
> the re-run on that architecture. Drop vmlinux from the unconditional
> list, and instead conditionally delete it only when the boot image
> basename is not vmlinux.
>
> In addition, identify qemu_binary before the copy step so that on
> non-PowerPC systems (where vmlinux is not the boot image) the vmlinux
> file can be removed immediately after the run directory is copied,
> saving storage before any tests run. This also eliminates the
> per-iteration re-computation of qemu_binary and boot_image inside
> the qemu-cmd transform loop.
>
> Tested on a local x86_64 machine and on a PPC VM of the Open Source Lab
> of Oregon State University.
>
> Signed-off-by: Zhouyi Zhou <[email protected]>
Queued for review and testing, thank you!
Thanx, Paul
> ---
> Changes in v3:
> - Identify qemu_binary and boot_image earlier, before the copy step,
> so that vmlinux can be removed right after copying the run directory
> on non-PowerPC systems, saving storage. This also eliminates the
> per-iteration re-computation of qemu_binary and boot_image inside
> the qemu-cmd transform loop.
> Suggested-by: Paul E. McKenney <[email protected]>
> ---
> tools/testing/selftests/rcutorture/bin/kvm-again.sh | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/tools/testing/selftests/rcutorture/bin/kvm-again.sh
> b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
> index b5239b52cb5d..9060b3dc8926 100755
> --- a/tools/testing/selftests/rcutorture/bin/kvm-again.sh
> +++ b/tools/testing/selftests/rcutorture/bin/kvm-again.sh
> @@ -180,6 +180,9 @@ fi
>
> echo ---- Re-run results directory: $rundir
>
> +qemu_binary="$(find "$oldrun" -maxdepth 2 -name 'qemu-cmd' -type f
> 2>/dev/null | head -1 | xargs -r grep -v '^#' 2>/dev/null | awk 'NF { print
> $1; exit }')"
> +boot_image="`identify_boot_image "$qemu_binary"`"
> +
> if test "$oldrun" != "$rundir"
> then
> # Copy old run directory tree over and adjust.
> @@ -189,7 +192,7 @@ then
> echo "Cannot copy from $oldrun to $rundir."
> usage
> fi
> - rm -f
> "$rundir"/*/{console.log,console.log.diags,qemu_pid,qemu-pid,qemu-retval,Warnings,kvm-test-1-run.sh.out,kvm-test-1-run-qemu.sh.out,vmlinux}
> "$rundir"/log
> + rm -f
> "$rundir"/*/{console.log,console.log.diags,qemu_pid,qemu-pid,qemu-retval,Warnings,kvm-test-1-run.sh.out,kvm-test-1-run-qemu.sh.out}
> "$rundir"/log
> touch "$rundir/log"
> echo $scriptname $args | tee -a "$rundir/log"
> echo $oldrun > "$rundir/re-run"
> @@ -197,6 +200,10 @@ then
> then
> $arg_link "$oldrun/../../bin" "$rundir/../.."
> fi
> + if test "`basename "$boot_image"`" != vmlinux
> + then
> + rm -f "$rundir"/*/vmlinux
> + fi
> else
> # Check for a run having already happened.
> find "$rundir" -name console.log -print > $T/oldrun-console.log
> @@ -217,7 +224,7 @@ do
> qemu_cmd_dir="`dirname "$i"`"
> kernel_dir="`echo $qemu_cmd_dir | sed -e 's/\.[0-9]\+$//'`"
> jitter_dir="`dirname "$kernel_dir"`"
> - kvm-transform.sh "$kernel_dir/bzImage" "$qemu_cmd_dir/console.log"
> "$jitter_dir" "$dur" "$bootargs" < $T/qemu-cmd > $i
> + kvm-transform.sh "$kernel_dir/`basename $boot_image`"
> "$qemu_cmd_dir/console.log" "$jitter_dir" "$dur" "$bootargs" < $T/qemu-cmd >
> $i
> if test -n "$arg_remote"
> then
> echo "# TORTURE_KCONFIG_GDB_ARG=''" >> $i
> --
> 2.43.0
>
