| Message ID | 2783932.o7RC7vMDHB@vostro.rjw.lan (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Rafael J. Wysocki <rjw@rjwysocki.net> [150706 15:49]: > On Monday, July 06, 2015 01:01:18 PM Felipe Balbi wrote: > > on a first call to dev_pm_attach_wake_irq(), if it > > fails, it will leave dev->power.wakeirq set to a > > dangling pointer. Instead, let's clear it to make > > sure a subsequent call to dev_pm_attach_wake_irq() > > has chance to succeed. > > > > Cc: Tony Lindgren <tmlind@atomide.com> > > Signed-off-by: Felipe Balbi <balbi@ti.com> > > --- > > drivers/base/power/wakeirq.c | 9 ++++++++- > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c > > index 7470004ca810..394d250a1ad8 100644 > > --- a/drivers/base/power/wakeirq.c > > +++ b/drivers/base/power/wakeirq.c > > @@ -50,9 +50,16 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq, > > > > err = device_wakeup_attach_irq(dev, wirq); > > if (err) > > - return err; > > + goto err_cleanup; > > > > return 0; > > + > > +err_cleanup: > > + spin_lock_irqsave(&dev->power.lock, flags); > > + dev->power.wakeirq = NULL; > > + spin_unlock_irqrestore(&dev->power.lock, flags); > > + > > + return err; > > } > > Too many labels for me and the fact that acquiring of the lock again in the error > patch doesn't look good. > > However, we can do the entire device_wakeup_attach_irq() under the lock (after > removing the locking from it), because we're its only caller. > > So what about the below instead (build-tested only)? Nice, still works for me and simplifies things: Tested-by: Tony Lindgren <tony@atomide.com>
On Tue, Jul 07, 2015 at 12:40:53AM -0700, Tony Lindgren wrote: > * Rafael J. Wysocki <rjw@rjwysocki.net> [150706 15:49]: > > On Monday, July 06, 2015 01:01:18 PM Felipe Balbi wrote: > > > on a first call to dev_pm_attach_wake_irq(), if it > > > fails, it will leave dev->power.wakeirq set to a > > > dangling pointer. Instead, let's clear it to make > > > sure a subsequent call to dev_pm_attach_wake_irq() > > > has chance to succeed. > > > > > > Cc: Tony Lindgren <tmlind@atomide.com> > > > Signed-off-by: Felipe Balbi <balbi@ti.com> > > > --- > > > drivers/base/power/wakeirq.c | 9 ++++++++- > > > 1 file changed, 8 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c > > > index 7470004ca810..394d250a1ad8 100644 > > > --- a/drivers/base/power/wakeirq.c > > > +++ b/drivers/base/power/wakeirq.c > > > @@ -50,9 +50,16 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq, > > > > > > err = device_wakeup_attach_irq(dev, wirq); > > > if (err) > > > - return err; > > > + goto err_cleanup; > > > > > > return 0; > > > + > > > +err_cleanup: > > > + spin_lock_irqsave(&dev->power.lock, flags); > > > + dev->power.wakeirq = NULL; > > > + spin_unlock_irqrestore(&dev->power.lock, flags); > > > + > > > + return err; > > > } > > > > Too many labels for me and the fact that acquiring of the lock again in the error > > patch doesn't look good. > > > > However, we can do the entire device_wakeup_attach_irq() under the lock (after > > removing the locking from it), because we're its only caller. > > > > So what about the below instead (build-tested only)? > > Nice, still works for me and simplifies things: > > Tested-by: Tony Lindgren <tony@atomide.com> Cool, thanks for testing Tony. Rafael, I'm fine with your version too. FWIW: Reported-by: Felipe Balbi <balbi@ti.com>
On Tue, Jul 7, 2015 at 10:11 AM, Felipe Balbi <balbi@ti.com> wrote: > On Tue, Jul 07, 2015 at 12:40:53AM -0700, Tony Lindgren wrote: >> * Rafael J. Wysocki <rjw@rjwysocki.net> [150706 15:49]: >> > On Monday, July 06, 2015 01:01:18 PM Felipe Balbi wrote: >> > > on a first call to dev_pm_attach_wake_irq(), if it >> > > fails, it will leave dev->power.wakeirq set to a >> > > dangling pointer. Instead, let's clear it to make >> > > sure a subsequent call to dev_pm_attach_wake_irq() >> > > has chance to succeed. >> > > >> > > Cc: Tony Lindgren <tmlind@atomide.com> >> > > Signed-off-by: Felipe Balbi <balbi@ti.com> >> > > --- >> > > drivers/base/power/wakeirq.c | 9 ++++++++- >> > > 1 file changed, 8 insertions(+), 1 deletion(-) >> > > >> > > diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c >> > > index 7470004ca810..394d250a1ad8 100644 >> > > --- a/drivers/base/power/wakeirq.c >> > > +++ b/drivers/base/power/wakeirq.c >> > > @@ -50,9 +50,16 @@ static int dev_pm_attach_wake_irq(struct device *dev, int irq, >> > > >> > > err = device_wakeup_attach_irq(dev, wirq); >> > > if (err) >> > > - return err; >> > > + goto err_cleanup; >> > > >> > > return 0; >> > > + >> > > +err_cleanup: >> > > + spin_lock_irqsave(&dev->power.lock, flags); >> > > + dev->power.wakeirq = NULL; >> > > + spin_unlock_irqrestore(&dev->power.lock, flags); >> > > + >> > > + return err; >> > > } >> > >> > Too many labels for me and the fact that acquiring of the lock again in the error >> > patch doesn't look good. >> > >> > However, we can do the entire device_wakeup_attach_irq() under the lock (after >> > removing the locking from it), because we're its only caller. >> > >> > So what about the below instead (build-tested only)? >> >> Nice, still works for me and simplifies things: >> >> Tested-by: Tony Lindgren <tony@atomide.com> > > Cool, thanks for testing Tony. Rafael, I'm fine with your version too. > FWIW: > > Reported-by: Felipe Balbi <balbi@ti.com> OK, applied. Thanks, Rafael
Index: linux-pm/drivers/base/power/wakeirq.c =================================================================== --- linux-pm.orig/drivers/base/power/wakeirq.c +++ linux-pm/drivers/base/power/wakeirq.c @@ -45,14 +45,12 @@ static int dev_pm_attach_wake_irq(struct return -EEXIST; } - dev->power.wakeirq = wirq; - spin_unlock_irqrestore(&dev->power.lock, flags); - err = device_wakeup_attach_irq(dev, wirq); - if (err) - return err; + if (!err) + dev->power.wakeirq = wirq; - return 0; + spin_unlock_irqrestore(&dev->power.lock, flags); + return err; } /** @@ -105,10 +103,10 @@ void dev_pm_clear_wake_irq(struct device return; spin_lock_irqsave(&dev->power.lock, flags); + device_wakeup_detach_irq(dev); dev->power.wakeirq = NULL; spin_unlock_irqrestore(&dev->power.lock, flags); - device_wakeup_detach_irq(dev); if (wirq->dedicated_irq) free_irq(wirq->irq, wirq); kfree(wirq); Index: linux-pm/drivers/base/power/wakeup.c =================================================================== --- linux-pm.orig/drivers/base/power/wakeup.c +++ linux-pm/drivers/base/power/wakeup.c @@ -281,32 +281,25 @@ EXPORT_SYMBOL_GPL(device_wakeup_enable); * Attach a device wakeirq to the wakeup source so the device * wake IRQ can be configured automatically for suspend and * resume. + * + * Call under the device's power.lock lock. */ int device_wakeup_attach_irq(struct device *dev, struct wake_irq *wakeirq) { struct wakeup_source *ws; - int ret = 0; - spin_lock_irq(&dev->power.lock); ws = dev->power.wakeup; if (!ws) { dev_err(dev, "forgot to call call device_init_wakeup?\n"); - ret = -EINVAL; - goto unlock; + return -EINVAL; } - if (ws->wakeirq) { - ret = -EEXIST; - goto unlock; - } + if (ws->wakeirq) + return -EEXIST; ws->wakeirq = wakeirq; - -unlock: - spin_unlock_irq(&dev->power.lock); - - return ret; + return 0; } /** @@ -314,20 +307,16 @@ unlock: * @dev: Device to handle * * Removes a device wakeirq from the wakeup source. + * + * Call under the device's power.lock lock. */ void device_wakeup_detach_irq(struct device *dev) { struct wakeup_source *ws; - spin_lock_irq(&dev->power.lock); ws = dev->power.wakeup; - if (!ws) - goto unlock; - - ws->wakeirq = NULL; - -unlock: - spin_unlock_irq(&dev->power.lock); + if (ws) + ws->wakeirq = NULL; } /**