Re: kernel oops in 'typec_ucsi' due to commit 'drivers property: When no children in primary, try secondary'

From: Andy Shevchenko
Date: Thu Jul 16 2020 - 11:47:25 EST


On Thu, Jul 16, 2020 at 11:17:03AM +0300, Maxim Levitsky wrote:
> Hi!
>
> Few days ago I bisected a regression on 5.8 kernel:
>
> I have nvidia rtx 2070s and its USB type C port driver (which is open source)
> started to crash on load:

...

> Reverting the commit helped fix this oops.
>
> My .config attached.
> If any more info is needed I'll be happy to provide it,
> and of course test patches.

Can you test below?

diff --git a/drivers/base/property.c b/drivers/base/property.c
index 1e6d75e65938..d58aa98fe964 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -721,7 +721,7 @@ struct fwnode_handle *device_get_next_child_node(struct device *dev,
return next;

/* When no more children in primary, continue with secondary */
- if (!IS_ERR_OR_NULL(fwnode->secondary))
+ if (fwnode && !IS_ERR_OR_NULL(fwnode->secondary))
next = fwnode_get_next_child_node(fwnode->secondary, child);

return next;
--
With Best Regards,
Andy Shevchenko