Re: [PATCH v8 10/10] xen: introduce ERRP_AUTO_PROPAGATE

[Paul Durrant <paul@xen.org>]

On Fri, 6 Mar 2020 at 05:16, Vladimir Sementsov-Ogievskiy
<vsementsov@virtuozzo.com> wrote:
>
> If we want to add some info to errp (by error_prepend() or
> error_append_hint()), we must use the ERRP_AUTO_PROPAGATE macro.
> Otherwise, this info will not be added when errp == &error_fatal
> (the program will exit prior to the error_append_hint() or
> error_prepend() call).  Fix such cases.
>
> If we want to check error after errp-function call, we need to
> introduce local_err and then propagate it to errp. Instead, use
> ERRP_AUTO_PROPAGATE macro, benefits are:
> 1. No need of explicit error_propagate call
> 2. No need of explicit local_err variable: use errp directly
> 3. ERRP_AUTO_PROPAGATE leaves errp as is if it's not NULL or
>    &error_fatal, this means that we don't break error_abort
>    (we'll abort on error_set, not on error_propagate)
>
> This commit is generated by command
>
>     sed -n '/^X86 Xen CPUs$/,/^$/{s/^F: //p}' MAINTAINERS | \
>     xargs git ls-files | grep '\.[hc]$' | \
>     xargs spatch \
>         --sp-file scripts/coccinelle/auto-propagated-errp.cocci \
>         --macro-file scripts/cocci-macro-file.h \
>         --in-place --no-show-diff --max-width 80
>
> Reported-by: Kevin Wolf <kwolf@redhat.com>
> Reported-by: Greg Kurz <groug@kaod.org>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

Reviewed-by: Paul Durrant <paul@xen.org>