On Thu, Sep 10, 2020 at 08:32:04AM -0700, Guenter Roeck wrote:
> Since v5.8, powerpc:allmodconfig often fails to build with the following
> error message.
>
> Inconsistent kallsyms data
> Try make KALLSYMS_EXTRA_PASS=1 as a workaround
>
> Setting KALLSYMS_EXTRA_PASS=1 does not help. As it turns out, the build
> currently needs up to four link passes to succeed.
>
> Similar problems have been observed over time for other architectures.
>
> Make the number of link passes dynamic to solve the problem. Try up to
> eight passes before giving up. If KALLSYMS_EXTRA_PASS is set, add one
> additional pass after succeeding.
>
> Suggested-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
I still see a build failure for powerpc:allmodconfig due to this problem.
Feedback/comments/thoughts ? Does anyone have a better idea ?
Thanks,
Guenter
> ---
> scripts/link-vmlinux.sh | 31 +++++++++++++++++++------------
> 1 file changed, 19 insertions(+), 12 deletions(-)
>
> diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
> index e6e2d9e5ff48..72abdee0e649 100755
> --- a/scripts/link-vmlinux.sh
> +++ b/scripts/link-vmlinux.sh
> @@ -316,11 +316,10 @@ if [ -n "${CONFIG_KALLSYMS}" ]; then
> # From here, we generate a correct .tmp_kallsyms2.o
> # 3) That link may have expanded the kernel image enough that
> # more linker branch stubs / trampolines had to be added, which
> - # introduces new names, which further expands kallsyms. Do another
> - # pass if that is the case. In theory it's possible this results
> - # in even more stubs, but unlikely.
> - # KALLSYMS_EXTRA_PASS=1 may also used to debug or work around
> - # other bugs.
> + # introduces new names, which further expands kallsyms. Try up
> + # to eight passes to handle that situation before giving up.
> + # KALLSYMS_EXTRA_PASS=1 may be used to add an extra step
> + # for debugging or to work around other bugs.
> # 4) The correct ${kallsymso} is linked into the final vmlinux.
> #
> # a) Verify that the System.map from vmlinux matches the map from
> @@ -329,13 +328,21 @@ if [ -n "${CONFIG_KALLSYMS}" ]; then
> kallsyms_step 1
> kallsyms_step 2
>
> - # step 3
> - size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso_prev})
> - size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso})
> -
> - if [ $size1 -ne $size2 ] || [ -n "${KALLSYMS_EXTRA_PASS}" ]; then
> - kallsyms_step 3
> - fi
> + # step n
> + step=3
> + while [ $step -le 8 ]; do
> + size1=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso_prev})
> + size2=$(${CONFIG_SHELL} "${srctree}/scripts/file-size.sh" ${kallsymso})
> +
> + if [ $size1 -eq $size2 ]; then
> + if [ -z "${KALLSYMS_EXTRA_PASS}" ]; then
> + break
> + fi
> + KALLSYMS_EXTRA_PASS=""
> + fi
> + kallsyms_step $step
> + step="$(expr $step + 1)"
> + done
> fi
>
> vmlinux_link vmlinux "${kallsymso}" ${btf_vmlinux_bin_o}
> --
> 2.17.1
>
