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FAILED: patch "[PATCH] PM / Domains: defer dev_pm_domain_set() until" failed to apply to 4.4-stable tree

PATCH In review [email protected] 2 participants 3 messages Jul 25, 2017 – Aug 3, 2017

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[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

Quoted 1 line

From 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 Mon Sep 17 00:00:00 2001

From: Sudeep Holla <[email protected]>
Date: Fri, 14 Jul 2017 11:51:48 +0100
Subject: [PATCH] PM / Domains: defer dev_pm_domain_set() until
genpd->attach_dev succeeds if present

If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets the PM domain for the device unconditionally.

When subsequent attempts are made to call genpd_dev_pm_attach, it may return -EEXISTS checking dev->pm_domain without re-attempting to call attach_dev or power_on.

platform_drv_probe then attempts to call drv->probe as the return value -EEXIST != -EPROBE_DEFER, which may end up in a situation where the device is accessed without it's power domain switched on.

Fixes f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data)
Cc 4.4+ <[email protected]> # v4.4+
Signed-off-by Sudeep Holla <[email protected]>
Acked-by Ulf Hansson <[email protected]>
Signed-off-by Rafael J. Wysocki <[email protected]>
drivers/base/power/domain.c +4 -4
index 2ac906288a6f..91ba82688f4c 100644
@@ -1222,8 +1222,6 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
 
 	spin_unlock_irq(&dev->power.lock);
 
-	dev_pm_domain_set(dev, &genpd->domain);
-
 	return gpd_data;
 
  err_free:

@@ -1237,8 +1235,6 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
 static void genpd_free_dev_data(struct device *dev,
 				struct generic_pm_domain_data *gpd_data)
 {
-	dev_pm_domain_set(dev, NULL);
-
 	spin_lock_irq(&dev->power.lock);
 
 	dev->power.subsys_data->domain_data = NULL;

@@ -1275,6 +1271,8 @@ static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 	if (ret)
 		goto out;
 
+	dev_pm_domain_set(dev, &genpd->domain);
+
 	genpd->device_count++;
 	genpd->max_off_time_changed = true;
 

@@ -1336,6 +1334,8 @@ static int genpd_remove_device(struct generic_pm_domain *genpd,
 	if (genpd->detach_dev)
 		genpd->detach_dev(genpd, dev);
 
+	dev_pm_domain_set(dev, NULL);
+
 	list_del_init(&pdd->list_node);
 
 	genpd_unlock(genpd);
#1 lore raw

PATCH 1/1 PM / Domains: defer setting dev->pm_domain until genpd->attach_dev succeeds if present

commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream.

If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets the PM domain for the device unconditionally.

When subsequent attempts are made to call genpd_dev_pm_attach, it may return -EEXISTS checking dev->pm_domain without re-attempting to call attach_dev or power_on.

platform_drv_probe then attempts to call drv->probe as the return value -EEXIST != -EPROBE_DEFER, which may end up in a situation where the device is accessed without it's power domain switched on.

Fixes f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data)
Cc 4.4+ <[email protected]> # v4.4+
Signed-off-by Sudeep Holla <[email protected]>
Acked-by Ulf Hansson <[email protected]>
Signed-off-by Rafael J. Wysocki <[email protected]>
---
 drivers/base/power/domain.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
drivers/base/power/domain.c +4 -2
index a48824deabc5..da5718e7fbb7 100644
@@ -1188,7 +1188,6 @@ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
 	}
 
 	dev->power.subsys_data->domain_data = &gpd_data->base;
-	dev->pm_domain = &genpd->domain;
 
 	spin_unlock_irq(&dev->power.lock);
 

@@ -1207,7 +1206,6 @@ static void genpd_free_dev_data(struct device *dev,
 {
 	spin_lock_irq(&dev->power.lock);
 
-	dev->pm_domain = NULL;
 	dev->power.subsys_data->domain_data = NULL;
 
 	spin_unlock_irq(&dev->power.lock);

@@ -1248,6 +1246,8 @@ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
 	if (ret)
 		goto out;
 
+	dev->pm_domain = &genpd->domain;
+
 	genpd->device_count++;
 	genpd->max_off_time_changed = true;
 

@@ -1299,6 +1299,8 @@ int pm_genpd_remove_device(struct generic_pm_domain *genpd,
 	if (genpd->detach_dev)
 		genpd->detach_dev(genpd, dev);
 
+	dev->pm_domain = NULL;
+
 	list_del_init(&pdd->list_node);
 
 	mutex_unlock(&genpd->lock);

--
2.7.4

author maintainer
#2 lore raw

Re: [PATCH v4.4 STABLE] PM / Domains: defer setting dev->pm_domain until genpd->attach_dev succeeds if present

Quoted 14 lines · Sudeep Holla

commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream.

If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets the PM domain for the device unconditionally.

When subsequent attempts are made to call genpd_dev_pm_attach, it may return -EEXISTS checking dev->pm_domain without re-attempting to call attach_dev or power_on.

platform_drv_probe then attempts to call drv->probe as the return value -EEXIST != -EPROBE_DEFER, which may end up in a situation where the device is accessed without it's power domain switched on.

Quoted 8 lines
Fixes f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data)
Cc 4.4+ <[email protected]> # v4.4+
Signed-off-by Sudeep Holla <[email protected]>
Acked-by Ulf Hansson <[email protected]>
Signed-off-by Rafael J. Wysocki <[email protected]>
---
 drivers/base/power/domain.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

Now applied, thanks.

greg k-h