From: Michael Tretter <m.tretter@pengutronix.de>
To: Michael Riesch <michael.riesch@wolfvision.net>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH 1/2] of: overlay: improve error handling in of_overlay_apply_tree
Date: Wed, 21 Sep 2022 09:57:05 +0200 [thread overview]
Message-ID: <20220921075705.GD16312@pengutronix.de> (raw)
In-Reply-To: <2ab1b3d8-eff0-f012-94bb-a6ddc61b982f@wolfvision.net>
On Wed, 21 Sep 2022 08:55:12 +0200, Michael Riesch wrote:
> On 9/5/22 12:07, Michael Riesch wrote:
> > Propagate any error from of_overlay_apply_symbols and let the user
> > know if the provided overlay is not applicable.
> >
> > Signed-off-by: Michael Riesch <michael.riesch@wolfvision.net>
> > ---
> > drivers/of/overlay.c | 14 +++++++++-----
> > 1 file changed, 9 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c
> > index 20a43f5170..20686db511 100644
> > --- a/drivers/of/overlay.c
> > +++ b/drivers/of/overlay.c
> > @@ -115,8 +115,8 @@ static char *of_overlay_fix_path(struct device_node *root,
> > return basprintf("%s%s", target->full_name, path_tail);
> > }
> >
> > -static void of_overlay_apply_symbols(struct device_node *root,
> > - struct device_node *overlay)
> > +static int of_overlay_apply_symbols(struct device_node *root,
> > + struct device_node *overlay)
> > {
> > const char *old_path;
> > char *new_path;
> > @@ -129,12 +129,12 @@ static void of_overlay_apply_symbols(struct device_node *root,
> >
> > if (!overlay_symbols) {
> > pr_debug("overlay doesn't have a __symbols__ node\n");
> > - return;
> > + return -EINVAL;
>
> Come to think of it, do all overlays need to provide a __symbols__ node?
> If not, this check is overly strict.
Overlays don't need a __symbols__ node. It would be only required, if overlays
are stacked and the second overlay refers to nodes of the first overlay by
labels. Having no __symbols__ in the overlay is a success path and the message
is just a debug message.
>
> > }
> >
> > if (!root_symbols) {
> > pr_info("root doesn't have a __symbols__ node\n");
> > - return;
> > + return -EINVAL;
>
> Ditto for the root.
I'm not sure what should happen, if the root does not have __symbols__.
Barebox wouldn't be able to copy the __symbols__ of the overlay, but this
still wouldn't be a problem unless overlays are stacked. In the stacking case,
only applying the second overlay should fail.
Maybe, we should add a new __symbols__ node, if the root doesn't have a
__symbols__ node?
>
> > }
> >
> > list_for_each_entry(prop, &overlay_symbols->properties, list) {
> > @@ -148,6 +148,8 @@ static void of_overlay_apply_symbols(struct device_node *root,
> > prop->name, new_path);
> > of_property_write_string(root_symbols, prop->name, new_path);
> > }
> > +
> > + return 0;
> > }
> >
> > static int of_overlay_apply_fragment(struct device_node *root,
> > @@ -190,7 +192,9 @@ int of_overlay_apply_tree(struct device_node *root,
> > goto out_err;
> >
> > /* Copy symbols from resolved overlay to base device tree */
> > - of_overlay_apply_symbols(root, resolved);
> > + err = of_overlay_apply_symbols(root, resolved);
> > + if (err)
> > + goto out_err;
>
> If both checks need to be relaxed, the complete patch should be reverted
> I guess :-/
What did you do to run into this error? What was your expectation?
Michael
next prev parent reply other threads:[~2022-09-21 7:59 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-05 10:07 [PATCH 0/2] of: overlay: avoid potential null pointer exception Michael Riesch
2022-09-05 10:07 ` [PATCH 1/2] of: overlay: improve error handling in of_overlay_apply_tree Michael Riesch
2022-09-21 6:55 ` Michael Riesch
2022-09-21 7:57 ` Michael Tretter [this message]
2022-09-21 10:00 ` Michael Riesch
2022-09-05 10:07 ` [PATCH 2/2] of: overlay: avoid potential null pointer exception Michael Riesch
2022-09-12 9:16 ` [PATCH 0/2] " Sascha Hauer
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220921075705.GD16312@pengutronix.de \
--to=m.tretter@pengutronix.de \
--cc=barebox@lists.infradead.org \
--cc=michael.riesch@wolfvision.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox