2017-12-15 13:40:42

by Loys Ollivier

[permalink] [raw]
Subject: [PATCH v3] firmware: qcom: scm: Fix incorrect of_node_put calls in scm_init

When using other platform architectures, in the init of the qcom_scm
driver, of_node_put is called on /firmware if no qcom dt is found.
This results in a kernel error: Bad of_node_put() on /firmware.

These calls to of_node_put from the qcom_scm init are unnecessary as
of_find_matching_node and of_platform_populate are calling it
automatically.

Remove the calls to of_node_put() on fw_np.

Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver")
Suggested-by: Stephen Boyd <[email protected]>
Signed-off-by: Loys Ollivier <[email protected]>
---
drivers/firmware/qcom_scm.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index af4c75217ea6..f6d7b7cffe0c 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -632,17 +632,13 @@ static int __init qcom_scm_init(void)

np = of_find_matching_node(fw_np, qcom_scm_dt_match);

- if (!np) {
- of_node_put(fw_np);
+ if (!np)
return -ENODEV;
- }

of_node_put(np);

ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);

- of_node_put(fw_np);
-
if (ret)
return ret;

--
2.7.4


2018-01-15 13:25:39

by Loys Ollivier

[permalink] [raw]
Subject: Re: [PATCH v3] firmware: qcom: scm: Fix incorrect of_node_put calls in scm_init


Hello guys,

Any news on this fix ? Anything else you need on my side ?

Thanks

On 15/12/2017 14:40, Loys Ollivier wrote:
> When using other platform architectures, in the init of the qcom_scm
> driver, of_node_put is called on /firmware if no qcom dt is found.
> This results in a kernel error: Bad of_node_put() on /firmware.
>
> These calls to of_node_put from the qcom_scm init are unnecessary as
> of_find_matching_node and of_platform_populate are calling it
> automatically.
>
> Remove the calls to of_node_put() on fw_np.
>
> Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver")
> Suggested-by: Stephen Boyd <[email protected]>
> Signed-off-by: Loys Ollivier <[email protected]>
> ---
> drivers/firmware/qcom_scm.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
> index af4c75217ea6..f6d7b7cffe0c 100644
> --- a/drivers/firmware/qcom_scm.c
> +++ b/drivers/firmware/qcom_scm.c
> @@ -632,17 +632,13 @@ static int __init qcom_scm_init(void)
>
> np = of_find_matching_node(fw_np, qcom_scm_dt_match);
>
> - if (!np) {
> - of_node_put(fw_np);
> + if (!np)
> return -ENODEV;
> - }
>
> of_node_put(np);
>
> ret = of_platform_populate(fw_np, qcom_scm_dt_match, NULL, NULL);
>
> - of_node_put(fw_np);
> -
> if (ret)
> return ret;
>
>

2018-01-16 16:45:55

by Bjorn Andersson

[permalink] [raw]
Subject: Re: [PATCH v3] firmware: qcom: scm: Fix incorrect of_node_put calls in scm_init

On Fri 15 Dec 05:40 PST 2017, Loys Ollivier wrote:

> When using other platform architectures, in the init of the qcom_scm
> driver, of_node_put is called on /firmware if no qcom dt is found.
> This results in a kernel error: Bad of_node_put() on /firmware.
>
> These calls to of_node_put from the qcom_scm init are unnecessary as
> of_find_matching_node and of_platform_populate are calling it
> automatically.
>
> Remove the calls to of_node_put() on fw_np.
>
> Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver")
> Suggested-by: Stephen Boyd <[email protected]>
> Signed-off-by: Loys Ollivier <[email protected]>

Hi Loys,

Your patch is correct! We are however removing all this logic from
qcom_scm_init() in v4.16.

See:
https://git.kernel.org/pub/scm/linux/kernel/git/agross/linux.git/commit/?h=for-next&id=3aa0582fdb824139630298880fbf78d4ac774d3c
https://git.kernel.org/pub/scm/linux/kernel/git/agross/linux.git/commit/?h=for-next&id=3aa0582fdb824139630298880fbf78d4ac774d3c

Regards,
Bjorn

2018-01-16 17:41:17

by Sudeep Holla

[permalink] [raw]
Subject: Re: [PATCH v3] firmware: qcom: scm: Fix incorrect of_node_put calls in scm_init

Hi Loys, Bjorn,

On Tue, Jan 16, 2018 at 08:45:49AM -0800, Bjorn Andersson wrote:
> On Fri 15 Dec 05:40 PST 2017, Loys Ollivier wrote:
>
> > When using other platform architectures, in the init of the qcom_scm
> > driver, of_node_put is called on /firmware if no qcom dt is found.
> > This results in a kernel error: Bad of_node_put() on /firmware.
> >
> > These calls to of_node_put from the qcom_scm init are unnecessary as
> > of_find_matching_node and of_platform_populate are calling it
> > automatically.
> >
> > Remove the calls to of_node_put() on fw_np.
> >
> > Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver")
> > Suggested-by: Stephen Boyd <[email protected]>
> > Signed-off-by: Loys Ollivier <[email protected]>
>
> Hi Loys,
>
> Your patch is correct! We are however removing all this logic from
> qcom_scm_init() in v4.16.
>

Unfortunately I seem to have carried the same issue to the new place.
I am fine if Loys wants to post the patch for the same. Let me know if you
want me to post, I have one handy(attached for the reference)

Regards,
Sudeep

-->8

>From 7a563a6f793796339ba1b7a167a77f7353bdd58d Mon Sep 17 00:00:00 2001
From: Sudeep Holla <[email protected]>
Date: Tue, 16 Jan 2018 17:17:28 +0000
Subject: [PATCH] of: platform: fix OF node refcount leak

We need to call of_node_put() for device nodes obtained with
of_find_node_by_path().

Reported-by: Loys Ollivier <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Frank Rowand <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
---
drivers/of/platform.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 6a01dab597c7..c00d81dfac0b 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -514,8 +514,10 @@ static int __init of_platform_default_populate_init(void)
of_platform_device_create(node, NULL, NULL);

node = of_find_node_by_path("/firmware");
- if (node)
+ if (node) {
of_platform_populate(node, NULL, NULL, NULL);
+ of_node_put(node);
+ }

/* Populate everything else. */
of_platform_default_populate(NULL, NULL, NULL);
--
2.7.4

2018-01-17 23:48:33

by Andy Gross

[permalink] [raw]
Subject: Re: [PATCH v3] firmware: qcom: scm: Fix incorrect of_node_put calls in scm_init

On Tue, Jan 16, 2018 at 08:45:49AM -0800, Bjorn Andersson wrote:
> On Fri 15 Dec 05:40 PST 2017, Loys Ollivier wrote:
>
> > When using other platform architectures, in the init of the qcom_scm
> > driver, of_node_put is called on /firmware if no qcom dt is found.
> > This results in a kernel error: Bad of_node_put() on /firmware.
> >
> > These calls to of_node_put from the qcom_scm init are unnecessary as
> > of_find_matching_node and of_platform_populate are calling it
> > automatically.
> >
> > Remove the calls to of_node_put() on fw_np.
> >
> > Fixes: d0f6fa7ba2d6 ("firmware: qcom: scm: Convert SCM to platform driver")
> > Suggested-by: Stephen Boyd <[email protected]>
> > Signed-off-by: Loys Ollivier <[email protected]>
>
> Hi Loys,
>
> Your patch is correct! We are however removing all this logic from
> qcom_scm_init() in v4.16.
>
> See:
> https://git.kernel.org/pub/scm/linux/kernel/git/agross/linux.git/commit/?h=for-next&id=3aa0582fdb824139630298880fbf78d4ac774d3c
> https://git.kernel.org/pub/scm/linux/kernel/git/agross/linux.git/commit/?h=for-next&id=3aa0582fdb824139630298880fbf78d4ac774d3c


Yeah sorry for the delay in response. I pulled in the second part of a separate
fix that removes all that code from the qcom_scm. It made more sense to do it
automatically from the base code.

Andy