2019-09-01 11:22:59

by Remi Pommarel

[permalink] [raw]
Subject: [PATCH] iio: adc: meson_saradc: Fix memory allocation order

meson_saradc's irq handler uses priv->regmap so make sure that it is
allocated before the irq get enabled.

This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
managed resources are freed in the inverted order they had been
allocated, priv->regmap was freed before the spurious fake irq that
CONFIG_DEBUG_SHIRQ adds called the handler.

Reported-by: Elie Roudninski <[email protected]>
Signed-off-by: Remi Pommarel <[email protected]>
---
drivers/iio/adc/meson_saradc.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c
index 7b28d045d271..7b27306330a3 100644
--- a/drivers/iio/adc/meson_saradc.c
+++ b/drivers/iio/adc/meson_saradc.c
@@ -1219,6 +1219,11 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
if (IS_ERR(base))
return PTR_ERR(base);

+ priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+ priv->param->regmap_config);
+ if (IS_ERR(priv->regmap))
+ return PTR_ERR(priv->regmap);
+
irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
if (!irq)
return -EINVAL;
@@ -1228,11 +1233,6 @@ static int meson_sar_adc_probe(struct platform_device *pdev)
if (ret)
return ret;

- priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
- priv->param->regmap_config);
- if (IS_ERR(priv->regmap))
- return PTR_ERR(priv->regmap);
-
priv->clkin = devm_clk_get(&pdev->dev, "clkin");
if (IS_ERR(priv->clkin)) {
dev_err(&pdev->dev, "failed to get clkin\n");
--
2.20.1


2019-09-01 11:45:14

by Martin Blumenstingl

[permalink] [raw]
Subject: Re: [PATCH] iio: adc: meson_saradc: Fix memory allocation order

On Sun, Sep 1, 2019 at 12:45 PM Remi Pommarel <[email protected]> wrote:
>
> meson_saradc's irq handler uses priv->regmap so make sure that it is
> allocated before the irq get enabled.
>
> This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
> managed resources are freed in the inverted order they had been
> allocated, priv->regmap was freed before the spurious fake irq that
> CONFIG_DEBUG_SHIRQ adds called the handler.
>

Fixes: 3af109131b7eb8 ("iio: adc: meson-saradc: switch from polling to
interrupt mode")
> Reported-by: Elie Roudninski <[email protected]>
> Signed-off-by: Remi Pommarel <[email protected]>
Reviewed-by: Martin Blumenstingl <[email protected]>

thank you for fixing this!


Martin

2019-09-02 20:42:09

by Elie Roudninski

[permalink] [raw]
Subject: Re: [PATCH] iio: adc: meson_saradc: Fix memory allocation order

On Sun, Sep 1, 2019 at 12:29 PM Martin Blumenstingl
<[email protected]> wrote:
>
> On Sun, Sep 1, 2019 at 12:45 PM Remi Pommarel <[email protected]> wrote:
> >
> > meson_saradc's irq handler uses priv->regmap so make sure that it is
> > allocated before the irq get enabled.
> >
> > This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
> > managed resources are freed in the inverted order they had been
> > allocated, priv->regmap was freed before the spurious fake irq that
> > CONFIG_DEBUG_SHIRQ adds called the handler.
> >
>
> Fixes: 3af109131b7eb8 ("iio: adc: meson-saradc: switch from polling to
> interrupt mode")
> > Reported-by: Elie Roudninski <[email protected]>
> > Signed-off-by: Remi Pommarel <[email protected]>
> Reviewed-by: Martin Blumenstingl <[email protected]>
>
> thank you for fixing this!
The patch fixed the kernel panic I had, i can now successfully boot my
meson-gxl-s905x-libretech-cc boad using patched linux 5.2.11

Tested-by: Elie ROUDNINSKI <[email protected]>

Elie
>
>
> Martin

2019-09-05 00:04:56

by Kevin Hilman

[permalink] [raw]
Subject: Re: [PATCH] iio: adc: meson_saradc: Fix memory allocation order

Remi Pommarel <[email protected]> writes:

> meson_saradc's irq handler uses priv->regmap so make sure that it is
> allocated before the irq get enabled.
>
> This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
> managed resources are freed in the inverted order they had been
> allocated, priv->regmap was freed before the spurious fake irq that
> CONFIG_DEBUG_SHIRQ adds called the handler.
>
> Reported-by: Elie Roudninski <[email protected]>
> Signed-off-by: Remi Pommarel <[email protected]>

Reviewed-by: Kevin Hilman <[email protected]>

2019-09-08 13:01:28

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH] iio: adc: meson_saradc: Fix memory allocation order

On Mon, 2 Sep 2019 21:40:49 +0100
Elie Roudninski <[email protected]> wrote:

> On Sun, Sep 1, 2019 at 12:29 PM Martin Blumenstingl
> <[email protected]> wrote:
> >
> > On Sun, Sep 1, 2019 at 12:45 PM Remi Pommarel <[email protected]> wrote:
> > >
> > > meson_saradc's irq handler uses priv->regmap so make sure that it is
> > > allocated before the irq get enabled.
> > >
> > > This also fixes crash when CONFIG_DEBUG_SHIRQ is enabled, as device
> > > managed resources are freed in the inverted order they had been
> > > allocated, priv->regmap was freed before the spurious fake irq that
> > > CONFIG_DEBUG_SHIRQ adds called the handler.
> > >
> >
> > Fixes: 3af109131b7eb8 ("iio: adc: meson-saradc: switch from polling to
> > interrupt mode")
> > > Reported-by: Elie Roudninski <[email protected]>
> > > Signed-off-by: Remi Pommarel <[email protected]>
> > Reviewed-by: Martin Blumenstingl <[email protected]>
> >
> > thank you for fixing this!
> The patch fixed the kernel panic I had, i can now successfully boot my
> meson-gxl-s905x-libretech-cc boad using patched linux 5.2.11
>
> Tested-by: Elie ROUDNINSKI <[email protected]>
Rather than rush through a quick pull request I'm going to hold this one
until after the merge window.

Applied to the fixes-togreg branch of iio.git (which is now based
on staging-next).

Thanks,

Jonathan

>
> Elie
> >
> >
> > Martin