* [PATCH 2/5] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
@ 2012-09-04 16:14 Peter Senna Tschudin
2012-09-05 19:33 ` Ezequiel Garcia
2012-09-06 8:38 ` [PATCH v2] " Peter Senna Tschudin
0 siblings, 2 replies; 6+ messages in thread
From: Peter Senna Tschudin @ 2012-09-04 16:14 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: kernel-janitors, Julia.Lawall, linux-media, linux-kernel
From: Peter Senna Tschudin <peter.senna@gmail.com>
Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
{ ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
when != &ret
*if(...)
{
... when != ret = e2
when forall
return ret;
}
// </smpl>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
---
drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
index ad68bbe..58cf56d 100644
--- a/drivers/media/platform/s5p-tv/sdo_drv.c
+++ b/drivers/media/platform/s5p-tv/sdo_drv.c
@@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->fout_vpll = clk_get(dev, "fout_vpll");
if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
dev_err(dev, "failed to get clock 'fout_vpll'\n");
+ ret = -ENODEV;
goto fail_dacphy;
}
dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
@@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
if (IS_ERR_OR_NULL(sdev->vdac)) {
dev_err(dev, "failed to get regulator 'vdac'\n");
+ ret = -ENODEV;
goto fail_fout_vpll;
}
sdev->vdet = devm_regulator_get(dev, "vdet");
if (IS_ERR_OR_NULL(sdev->vdet)) {
dev_err(dev, "failed to get regulator 'vdet'\n");
+ ret = -ENODEV;
goto fail_fout_vpll;
}
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH 2/5] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
2012-09-04 16:14 [PATCH 2/5] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code Peter Senna Tschudin
@ 2012-09-05 19:33 ` Ezequiel Garcia
2012-09-06 8:38 ` [PATCH v2] " Peter Senna Tschudin
1 sibling, 0 replies; 6+ messages in thread
From: Ezequiel Garcia @ 2012-09-05 19:33 UTC (permalink / raw)
To: Peter Senna Tschudin
Cc: Mauro Carvalho Chehab, kernel-janitors, Julia.Lawall,
linux-media, linux-kernel
Hi Peter,
On Tue, Sep 4, 2012 at 1:14 PM, Peter Senna Tschudin
<peter.senna@gmail.com> wrote:
> From: Peter Senna Tschudin <peter.senna@gmail.com>
>
> Convert a nonnegative error return code to a negative one, as returned
> elsewhere in the function.
>
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
>
> // <smpl>
> (
> if@p1 (\(ret < 0\|ret != 0\))
> { ... return ret; }
> |
> ret@p1 = 0
> )
> ... when != ret = e1
> when != &ret
> *if(...)
> {
> ... when != ret = e2
> when forall
> return ret;
> }
>
> // </smpl>
>
> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
>
> ---
> drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
> index ad68bbe..58cf56d 100644
> --- a/drivers/media/platform/s5p-tv/sdo_drv.c
> +++ b/drivers/media/platform/s5p-tv/sdo_drv.c
> @@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->fout_vpll = clk_get(dev, "fout_vpll");
> if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
> dev_err(dev, "failed to get clock 'fout_vpll'\n");
> + ret = -ENODEV;
> goto fail_dacphy;
> }
> dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
> @@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
> if (IS_ERR_OR_NULL(sdev->vdac)) {
> dev_err(dev, "failed to get regulator 'vdac'\n");
> + ret = -ENODEV;
> goto fail_fout_vpll;
> }
> sdev->vdet = devm_regulator_get(dev, "vdet");
> if (IS_ERR_OR_NULL(sdev->vdet)) {
> dev_err(dev, "failed to get regulator 'vdet'\n");
> + ret = -ENODEV;
> goto fail_fout_vpll;
> }
>
>
Just a nitpick: why using ENODEV when the rest of the function is using ENXIO?
In which case, you could fix this with a less intrusive change, by
initializating ret to -ENXIO.
Hope this helps,
Ezequiel.
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
2012-09-04 16:14 [PATCH 2/5] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code Peter Senna Tschudin
2012-09-05 19:33 ` Ezequiel Garcia
@ 2012-09-06 8:38 ` Peter Senna Tschudin
2012-09-23 19:30 ` Fwd: " Mauro Carvalho Chehab
2012-09-24 9:16 ` Tomasz Stanislawski
1 sibling, 2 replies; 6+ messages in thread
From: Peter Senna Tschudin @ 2012-09-06 8:38 UTC (permalink / raw)
To: peter.senna, Mauro Carvalho Chehab; +Cc: linux-media, linux-kernel
From: Peter Senna Tschudin <peter.senna@gmail.com>
Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
{ ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
when != &ret
*if(...)
{
... when != ret = e2
when forall
return ret;
}
// </smpl>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
---
drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
index ad68bbe..58cf56d 100644
--- a/drivers/media/platform/s5p-tv/sdo_drv.c
+++ b/drivers/media/platform/s5p-tv/sdo_drv.c
@@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->fout_vpll = clk_get(dev, "fout_vpll");
if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
dev_err(dev, "failed to get clock 'fout_vpll'\n");
+ ret = -ENXIO;
goto fail_dacphy;
}
dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
@@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
if (IS_ERR_OR_NULL(sdev->vdac)) {
dev_err(dev, "failed to get regulator 'vdac'\n");
+ ret = -ENXIO;
goto fail_fout_vpll;
}
sdev->vdet = devm_regulator_get(dev, "vdet");
if (IS_ERR_OR_NULL(sdev->vdet)) {
dev_err(dev, "failed to get regulator 'vdet'\n");
+ ret = -ENXIO;
goto fail_fout_vpll;
}
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Fwd: [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
2012-09-06 8:38 ` [PATCH v2] " Peter Senna Tschudin
@ 2012-09-23 19:30 ` Mauro Carvalho Chehab
2012-09-24 10:00 ` Sylwester Nawrocki
2012-09-24 9:16 ` Tomasz Stanislawski
1 sibling, 1 reply; 6+ messages in thread
From: Mauro Carvalho Chehab @ 2012-09-23 19:30 UTC (permalink / raw)
To: Sylwester Nawrocki; +Cc: Peter Senna Tschudin, linux-media, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 2201 bytes --]
Sylwester,
Please review.
Regards,
Mauro
-------- Mensagem original --------
Assunto: [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
Data: Thu, 6 Sep 2012 10:38:29 +0200
De: Peter Senna Tschudin <peter.senna@gmail.com>
Para: peter.senna@gmail.com, Mauro Carvalho Chehab <mchehab@infradead.org>
CC: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
From: Peter Senna Tschudin <peter.senna@gmail.com>
Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
{ ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
when != &ret
*if(...)
{
... when != ret = e2
when forall
return ret;
}
// </smpl>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
---
drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
index ad68bbe..58cf56d 100644
--- a/drivers/media/platform/s5p-tv/sdo_drv.c
+++ b/drivers/media/platform/s5p-tv/sdo_drv.c
@@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->fout_vpll = clk_get(dev, "fout_vpll");
if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
dev_err(dev, "failed to get clock 'fout_vpll'\n");
+ ret = -ENXIO;
goto fail_dacphy;
}
dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
@@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
if (IS_ERR_OR_NULL(sdev->vdac)) {
dev_err(dev, "failed to get regulator 'vdac'\n");
+ ret = -ENXIO;
goto fail_fout_vpll;
}
sdev->vdet = devm_regulator_get(dev, "vdet");
if (IS_ERR_OR_NULL(sdev->vdet)) {
dev_err(dev, "failed to get regulator 'vdet'\n");
+ ret = -ENXIO;
goto fail_fout_vpll;
}
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[-- Attachment #2: Seção da mensagem anexada --]
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^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
2012-09-06 8:38 ` [PATCH v2] " Peter Senna Tschudin
2012-09-23 19:30 ` Fwd: " Mauro Carvalho Chehab
@ 2012-09-24 9:16 ` Tomasz Stanislawski
1 sibling, 0 replies; 6+ messages in thread
From: Tomasz Stanislawski @ 2012-09-24 9:16 UTC (permalink / raw)
To: Peter Senna Tschudin; +Cc: Mauro Carvalho Chehab, linux-media, linux-kernel
Hi.
On 09/06/2012 10:38 AM, Peter Senna Tschudin wrote:
> From: Peter Senna Tschudin <peter.senna@gmail.com>
>
> Convert a nonnegative error return code to a negative one, as returned
> elsewhere in the function.
>
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
>
> // <smpl>
> (
> if@p1 (\(ret < 0\|ret != 0\))
> { ... return ret; }
> |
> ret@p1 = 0
> )
> ... when != ret = e1
> when != &ret
> *if(...)
> {
> ... when != ret = e2
> when forall
> return ret;
> }
>
> // </smpl>
>
> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Acked-by: Tomasz Stanislawski <t.stanislaws@samsung.com>
>
> ---
> drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
> index ad68bbe..58cf56d 100644
> --- a/drivers/media/platform/s5p-tv/sdo_drv.c
> +++ b/drivers/media/platform/s5p-tv/sdo_drv.c
> @@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->fout_vpll = clk_get(dev, "fout_vpll");
> if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
> dev_err(dev, "failed to get clock 'fout_vpll'\n");
> + ret = -ENXIO;
> goto fail_dacphy;
> }
> dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
> @@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
> if (IS_ERR_OR_NULL(sdev->vdac)) {
> dev_err(dev, "failed to get regulator 'vdac'\n");
> + ret = -ENXIO;
> goto fail_fout_vpll;
> }
> sdev->vdet = devm_regulator_get(dev, "vdet");
> if (IS_ERR_OR_NULL(sdev->vdet)) {
> dev_err(dev, "failed to get regulator 'vdet'\n");
> + ret = -ENXIO;
> goto fail_fout_vpll;
> }
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Fwd: [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
2012-09-23 19:30 ` Fwd: " Mauro Carvalho Chehab
@ 2012-09-24 10:00 ` Sylwester Nawrocki
0 siblings, 0 replies; 6+ messages in thread
From: Sylwester Nawrocki @ 2012-09-24 10:00 UTC (permalink / raw)
To: Mauro Carvalho Chehab
Cc: Peter Senna Tschudin, linux-media, linux-kernel, Tomasz Stanislawski
On 09/23/2012 09:30 PM, Mauro Carvalho Chehab wrote:
> Sylwester,
>
> Please review.
>
> Regards,
> Mauro
>
> -------- Mensagem original --------
> Assunto: [PATCH v2] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code
> Data: Thu, 6 Sep 2012 10:38:29 +0200
> De: Peter Senna Tschudin <peter.senna@gmail.com>
> Para: peter.senna@gmail.com, Mauro Carvalho Chehab <mchehab@infradead.org>
> CC: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
>
> From: Peter Senna Tschudin <peter.senna@gmail.com>
>
> Convert a nonnegative error return code to a negative one, as returned
> elsewhere in the function.
>
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
>
> // <smpl>
> (
> if@p1 (\(ret < 0\|ret != 0\))
> { ... return ret; }
> |
> ret@p1 = 0
> )
> ... when != ret = e1
> when != &ret
> *if(...)
> {
> ... when != ret = e2
> when forall
> return ret;
> }
>
> // </smpl>
>
> Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
>
> ---
> drivers/media/platform/s5p-tv/sdo_drv.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c b/drivers/media/platform/s5p-tv/sdo_drv.c
> index ad68bbe..58cf56d 100644
> --- a/drivers/media/platform/s5p-tv/sdo_drv.c
> +++ b/drivers/media/platform/s5p-tv/sdo_drv.c
> @@ -369,6 +369,7 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->fout_vpll = clk_get(dev, "fout_vpll");
> if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
> dev_err(dev, "failed to get clock 'fout_vpll'\n");
> + ret = -ENXIO;
This patch improves the situation but it doesn't look like a proper fix
to me. First of all clk_get() return code should be checked only with
IS_ERR() and the error code should be propagated up to the caller, rather
than overwriting it with -ENXIO. It's important especially in cases where,
e.g we are getting EPROBE_DEFER instead of a valid resource.
> goto fail_dacphy;
> }
> dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
> @@ -377,11 +378,13 @@ static int __devinit sdo_probe(struct platform_device *pdev)
> sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
> if (IS_ERR_OR_NULL(sdev->vdac)) {
> dev_err(dev, "failed to get regulator 'vdac'\n");
> + ret = -ENXIO;
Same situation here..
> goto fail_fout_vpll;
> }
> sdev->vdet = devm_regulator_get(dev, "vdet");
> if (IS_ERR_OR_NULL(sdev->vdet)) {
> dev_err(dev, "failed to get regulator 'vdet'\n");
> + ret = -ENXIO;
> goto fail_fout_vpll;
> }
end here.
I think something more like this is needed (I'm going to queue this
patch for 3.7):
8<------------------------------------------------------------------
>From 8d3ce303461a2c09991efc5b86a0f56789045fa9 Mon Sep 17 00:00:00 2001
From: Sylwester Nawrocki <s.nawrocki@samsung.com>
Date: Mon, 24 Sep 2012 10:37:51 +0200
Subject: [PATCH] s5p-tv: Fix return value in sdo_probe() on error paths
Use proper return value test for clk_get() and devm_regulator_get()
functions and propagate any errors from the clock and the regulator
subsystem to the driver core. In two cases a proper error code is
now returned rather than 0.
Reported-by: Peter Senna Tschudin <peter.senna@gmail.com>
Cc: Tomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
drivers/media/platform/s5p-tv/sdo_drv.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)
diff --git a/drivers/media/platform/s5p-tv/sdo_drv.c
b/drivers/media/platform/s5p-tv/sdo_drv.c
index ad68bbe..2d1a654 100644
--- a/drivers/media/platform/s5p-tv/sdo_drv.c
+++ b/drivers/media/platform/s5p-tv/sdo_drv.c
@@ -341,47 +341,50 @@ static int __devinit sdo_probe(struct platform_device *pdev)
/* acquire clocks */
sdev->sclk_dac = clk_get(dev, "sclk_dac");
- if (IS_ERR_OR_NULL(sdev->sclk_dac)) {
+ if (IS_ERR(sdev->sclk_dac)) {
dev_err(dev, "failed to get clock 'sclk_dac'\n");
- ret = -ENXIO;
+ ret = PTR_ERR(sdev->sclk_dac);
goto fail;
}
sdev->dac = clk_get(dev, "dac");
- if (IS_ERR_OR_NULL(sdev->dac)) {
+ if (IS_ERR(sdev->dac)) {
dev_err(dev, "failed to get clock 'dac'\n");
- ret = -ENXIO;
+ ret = PTR_ERR(sdev->dac);
goto fail_sclk_dac;
}
sdev->dacphy = clk_get(dev, "dacphy");
- if (IS_ERR_OR_NULL(sdev->dacphy)) {
+ if (IS_ERR(sdev->dacphy)) {
dev_err(dev, "failed to get clock 'dacphy'\n");
- ret = -ENXIO;
+ ret = PTR_ERR(sdev->dacphy);
goto fail_dac;
}
sclk_vpll = clk_get(dev, "sclk_vpll");
- if (IS_ERR_OR_NULL(sclk_vpll)) {
+ if (IS_ERR(sclk_vpll)) {
dev_err(dev, "failed to get clock 'sclk_vpll'\n");
- ret = -ENXIO;
+ ret = PTR_ERR(sclk_vpll);
goto fail_dacphy;
}
clk_set_parent(sdev->sclk_dac, sclk_vpll);
clk_put(sclk_vpll);
sdev->fout_vpll = clk_get(dev, "fout_vpll");
- if (IS_ERR_OR_NULL(sdev->fout_vpll)) {
+ if (IS_ERR(sdev->fout_vpll)) {
dev_err(dev, "failed to get clock 'fout_vpll'\n");
+ ret = PTR_ERR(sdev->fout_vpll);
goto fail_dacphy;
}
dev_info(dev, "fout_vpll.rate = %lu\n", clk_get_rate(sclk_vpll));
/* acquire regulator */
sdev->vdac = devm_regulator_get(dev, "vdd33a_dac");
- if (IS_ERR_OR_NULL(sdev->vdac)) {
+ if (IS_ERR(sdev->vdac)) {
dev_err(dev, "failed to get regulator 'vdac'\n");
+ ret = PTR_ERR(sdev->vdac);
goto fail_fout_vpll;
}
sdev->vdet = devm_regulator_get(dev, "vdet");
- if (IS_ERR_OR_NULL(sdev->vdet)) {
+ if (IS_ERR(sdev->vdet)) {
dev_err(dev, "failed to get regulator 'vdet'\n");
+ ret = PTR_ERR(sdev->vdet);
goto fail_fout_vpll;
}
--
1.7.11.3
8<------------------------------------------------------------------
Regards,
Sylwester
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2012-09-24 10:00 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-09-04 16:14 [PATCH 2/5] drivers/media/platform/s5p-tv/sdo_drv.c: fix error return code Peter Senna Tschudin
2012-09-05 19:33 ` Ezequiel Garcia
2012-09-06 8:38 ` [PATCH v2] " Peter Senna Tschudin
2012-09-23 19:30 ` Fwd: " Mauro Carvalho Chehab
2012-09-24 10:00 ` Sylwester Nawrocki
2012-09-24 9:16 ` Tomasz Stanislawski
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