Re: [PATCH v4 2/5] dpkg: Limit unmount loop

[Henning Schild <henning.schild@siemens.com>]

Am Mon, 16 Aug 2021 18:37:53 +0300
schrieb Anton Mikanovich <amikan@ilbers.de>:

> In the past, unmounting WORKDIR caused infinite looping with the
> "Couldn't unmount, retrying..." warning if the first linux-mainline
> task failed and the second one succeeded (it is built for
> de0-nano-soc-buster and stm32mp15x-buster).
> 
> This change limits the loop to 1000 s.
> 
> Signed-off-by: Anton Mikanovich <amikan@ilbers.de>
> ---
>  meta/classes/dpkg-base.bbclass | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
> 
> diff --git a/meta/classes/dpkg-base.bbclass
> b/meta/classes/dpkg-base.bbclass index 4b189f1..105a1e6 100644
> --- a/meta/classes/dpkg-base.bbclass
> +++ b/meta/classes/dpkg-base.bbclass
> @@ -157,14 +157,16 @@ dpkg_do_mounts() {
>  }
>  
>  dpkg_undo_mounts() {
> -    i=1
> +    i=0
>      while ! sudo umount ${BUILDROOT}; do
>          sleep 0.1
> -        i=`expr $i + 1`
> -        if [ $i -gt 100 ]; then
> -            bbwarn "${BUILDROOT}: Couldn't unmount, retrying..."
> -            i=1
> +        if [ `expr $i % 100` -eq 0 ] ; then
> +            bbwarn "${BUILDROOT}: Couldn't unmount ($i), retrying..."
> +        fi
> +        if [ $i -gt 10000 ]; then
> +            bbfatal "${BUILDROOT}: Couldn't unmount after timeout"
>          fi
> +        i=`expr $i + 1`

IMHO it would be easier to read how long that will take in total ... if
it was "sleep 1" ... "% 10" and "-gt 1000" ... in fact i think it
should be "-ge 1000" now that you start with 0. But on off-by-one in a
timeout it not the biggest problem.

Henning

>      done
>      sudo rmdir ${BUILDROOT}
>  }