2023-07-13 11:08:22

by Li Chen

Subject: [PATCH V2] of: property: fw_devlink: fixup return value check of strcmp_suffix in parse_gpios

This commit addresses an issue where enabling fw_devlink=on was causing
a PCIe malfunction, resulting in endpoints missing.
After thorough investigation, it was determined that the root cause was
an incorrect usage of strcmp_suffix in parse_gpios.

Fixes: d473d32c2fba ("of: property: fw_devlink: do not link ".*,nr-gpios"")
Signed-off-by: Li Chen <[email protected]>
Cc: [email protected]
---
changes:
v1->v2: add Cc stable

drivers/of/property.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/property.c b/drivers/of/property.c
index ddc75cd50825..261eb8f3be08 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1272,7 +1272,7 @@ DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
static struct device_node *parse_gpios(struct device_node *np,
const char *prop_name, int index)
{
- if (!strcmp_suffix(prop_name, ",nr-gpios"))
+ if (strcmp_suffix(prop_name, ",nr-gpios"))
return NULL;

return parse_suffix_prop_cells(np, prop_name, index, "-gpios",
--
2.34.1

2023-07-13 17:07:50

by Rob Herring

Subject: Re: [PATCH V2] of: property: fw_devlink: fixup return value check of strcmp_suffix in parse_gpios

On Thu, Jul 13, 2023 at 4:47 AM Li Chen <[email protected]> wrote:
>
> This commit addresses an issue where enabling fw_devlink=on was causing
> a PCIe malfunction, resulting in endpoints missing.
> After thorough investigation, it was determined that the root cause was
> an incorrect usage of strcmp_suffix in parse_gpios.
>
> Fixes: d473d32c2fba ("of: property: fw_devlink: do not link ".*,nr-gpios"")
> Signed-off-by: Li Chen <[email protected]>
> Cc: [email protected]
> ---
> changes:
> v1->v2: add Cc stable
>
> drivers/of/property.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index ddc75cd50825..261eb8f3be08 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1272,7 +1272,7 @@ DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
> static struct device_node *parse_gpios(struct device_node *np,
> const char *prop_name, int index)
> {
> - if (!strcmp_suffix(prop_name, ",nr-gpios"))
> + if (strcmp_suffix(prop_name, ",nr-gpios"))

strcmp returns 0 when there is a match. When we match ",nr-gpios", we
want to bail out. The existing code was correct. Your patch just
disables fw_devlink for all GPIO dependencies.

Rob

2023-07-14 08:58:29

by Li Chen

Subject: Re: [PATCH V2] of: property: fw_devlink: fixup return value check of strcmp_suffix in parse_gpios

Hi Rob,
---- On Fri, 14 Jul 2023 00:45:24 +0800 Rob Herring wrote ---
> On Thu, Jul 13, 2023 at 4:47 AM Li Chen [email protected]> wrote:
> >
> > This commit addresses an issue where enabling fw_devlink=on was causing
> > a PCIe malfunction, resulting in endpoints missing.
> > After thorough investigation, it was determined that the root cause was
> > an incorrect usage of strcmp_suffix in parse_gpios.
> >
> > Fixes: d473d32c2fba ("of: property: fw_devlink: do not link ".*,nr-gpios"")
> > Signed-off-by: Li Chen [email protected]>
> > Cc: [email protected]
> > ---
> > changes:
> > v1->v2: add Cc stable
> >
> > drivers/of/property.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/of/property.c b/drivers/of/property.c
> > index ddc75cd50825..261eb8f3be08 100644
> > --- a/drivers/of/property.c
> > +++ b/drivers/of/property.c
> > @@ -1272,7 +1272,7 @@ DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")
> > static struct device_node *parse_gpios(struct device_node *np,
> > const char *prop_name, int index)
> > {
> > - if (!strcmp_suffix(prop_name, ",nr-gpios"))
> > + if (strcmp_suffix(prop_name, ",nr-gpios"))
>
> strcmp returns 0 when there is a match. When we match ",nr-gpios", we
> want to bail out. The existing code was correct. Your patch just
> disables fw_devlink for all GPIO dependencies.

Yes, your are correct, thanks!

Regards,
Li