| Message ID | 1412188697-15317-1-git-send-email-geert+renesas@glider.be (mailing list archive) |
|---|---|
| State | Accepted, archived |
| Headers | show |
Hi Rafael, On Wed, Oct 1, 2014 at 9:47 PM, Rafael J. Wysocki <rjw@rjwysocki.net> wrote: > On Wednesday, October 01, 2014 08:38:17 PM Geert Uytterhoeven wrote: >> Unlike the clocks management code for runtime PM, the code used for >> system suspend does not check the pm_clock_entry.status field. >> If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and >> ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT). >> >> Depending on the clock implementation, suspend or resume may crash with: >> >> Unable to handle kernel NULL pointer dereference at virtual address 00000026 >> >> (CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable() >> only has a NULL check; pre-CCF implementations may behave differently) >> >> While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't >> hurt to use the same state machine as is done for runtime PM, as this >> makes the two versions more similar, and eligible for a future >> consolidation. >> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> >> --- >> This crash started to happen on armadillo-legacy during s2ram if >> CONFIG_PM_RUNTIME is not set after applying "[PATCH v2 07/11] ARM: >> shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support" >> (http://www.spinics.net/linux/lists/arm-kernel/msg365438.html), as >> there's no NULL clock for the HDMI device. >> >> Most existing code calling pm_clk_suspend()/pm_clk_resume() is protected >> by a check for CONFIG_PM_RUNTIME (davinci, keystone, omap1, >> drivers/sh/pm_runtime.c), so it was not affected by this bug. >> >> Exceptions are: >> - arch/arm/mach-shmobile/pm-r8a7779.c (marzen), >> - arch/arm/mach-shmobile/pm-rmobile.c (r8a7740/armadillo and >> sh7372/mackerel), >> but it's difficult to assess from the code whether the bug is really >> triggered on these platforms. >> >> Grygorii Strashko's "[PATCH v1 2/4] ARM: keystone: pm: switch to use >> generic pm domains" is not affected, as pm_clk_add_clk() is only called >> for existing clocks. >> >> If it crashes on marzen or mackerel, I think this fix needs to be >> applied to stable, too. I don't have access to marzen or mackerel boards, >> though. >> >> How to test: >> - Build a kernel with CONFIG_PM_SLEEP/CONFIG_SUSPEND enabled, but >> CONFIG_PM_RUNTIME disabled, >> - echo 0 > /sys/module/printk/parameters/console_suspend, >> - echo mem > /sys/power/state, >> - wake up using e.g. gpio-keys or serial console activity. > > Do I think correctly that this would be 3.18 material? Yes indeed, so Simon can queue up the R-Mobile PM domain bits that will trigger this on armadillo for 3.19. If it can be triggered on marzen or mackerel now, I think we need it in stable, too. Thanks! Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wednesday, October 01, 2014 08:38:17 PM Geert Uytterhoeven wrote: > Unlike the clocks management code for runtime PM, the code used for > system suspend does not check the pm_clock_entry.status field. > If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and > ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT). > > Depending on the clock implementation, suspend or resume may crash with: > > Unable to handle kernel NULL pointer dereference at virtual address 00000026 > > (CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable() > only has a NULL check; pre-CCF implementations may behave differently) > > While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't > hurt to use the same state machine as is done for runtime PM, as this > makes the two versions more similar, and eligible for a future > consolidation. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > --- > This crash started to happen on armadillo-legacy during s2ram if > CONFIG_PM_RUNTIME is not set after applying "[PATCH v2 07/11] ARM: > shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support" > (http://www.spinics.net/linux/lists/arm-kernel/msg365438.html), as > there's no NULL clock for the HDMI device. > > Most existing code calling pm_clk_suspend()/pm_clk_resume() is protected > by a check for CONFIG_PM_RUNTIME (davinci, keystone, omap1, > drivers/sh/pm_runtime.c), so it was not affected by this bug. > > Exceptions are: > - arch/arm/mach-shmobile/pm-r8a7779.c (marzen), > - arch/arm/mach-shmobile/pm-rmobile.c (r8a7740/armadillo and > sh7372/mackerel), > but it's difficult to assess from the code whether the bug is really > triggered on these platforms. > > Grygorii Strashko's "[PATCH v1 2/4] ARM: keystone: pm: switch to use > generic pm domains" is not affected, as pm_clk_add_clk() is only called > for existing clocks. > > If it crashes on marzen or mackerel, I think this fix needs to be > applied to stable, too. I don't have access to marzen or mackerel boards, > though. > > How to test: > - Build a kernel with CONFIG_PM_SLEEP/CONFIG_SUSPEND enabled, but > CONFIG_PM_RUNTIME disabled, > - echo 0 > /sys/module/printk/parameters/console_suspend, > - echo mem > /sys/power/state, > - wake up using e.g. gpio-keys or serial console activity. Do I think correctly that this would be 3.18 material? > --- > drivers/base/power/clock_ops.c | 19 +++++++++++++++---- > 1 file changed, 15 insertions(+), 4 deletions(-) > > diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c > index b99e6c06ee678ecb..78369305e0698109 100644 > --- a/drivers/base/power/clock_ops.c > +++ b/drivers/base/power/clock_ops.c > @@ -368,8 +368,13 @@ int pm_clk_suspend(struct device *dev) > > spin_lock_irqsave(&psd->lock, flags); > > - list_for_each_entry_reverse(ce, &psd->clock_list, node) > - clk_disable(ce->clk); > + list_for_each_entry_reverse(ce, &psd->clock_list, node) { > + if (ce->status < PCE_STATUS_ERROR) { > + if (ce->status == PCE_STATUS_ENABLED) > + clk_disable(ce->clk); > + ce->status = PCE_STATUS_ACQUIRED; > + } > + } > > spin_unlock_irqrestore(&psd->lock, flags); > > @@ -385,6 +390,7 @@ int pm_clk_resume(struct device *dev) > struct pm_subsys_data *psd = dev_to_psd(dev); > struct pm_clock_entry *ce; > unsigned long flags; > + int ret; > > dev_dbg(dev, "%s()\n", __func__); > > @@ -394,8 +400,13 @@ int pm_clk_resume(struct device *dev) > > spin_lock_irqsave(&psd->lock, flags); > > - list_for_each_entry(ce, &psd->clock_list, node) > - __pm_clk_enable(dev, ce->clk); > + list_for_each_entry(ce, &psd->clock_list, node) { > + if (ce->status < PCE_STATUS_ERROR) { > + ret = __pm_clk_enable(dev, ce->clk); > + if (!ret) > + ce->status = PCE_STATUS_ENABLED; > + } > + } > > spin_unlock_irqrestore(&psd->lock, flags); > >
Upstream commit a968bed78b549b4c61d4a46e59161fc1f60f96a6
Author: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Wed Oct 1 20:38:17 2014 +0200
PM / clk: Fix crash in clocks management code if !CONFIG_PM_RUNTIME
Simon tried it on mackerel. It did not crash, but caused a warning and
backtrace:
WARNING: CPU: 0 PID: 1420 at drivers/sh/clk/core.c:240
__clk_disable+0x80/0x90()
Trying to disable clock c04bd4d8 with 0 usecount
which got fixed by the patch. So I think it should be applied to
-stable (v3.14 and up).
Thanks!
On Wed, Oct 1, 2014 at 8:38 PM, Geert Uytterhoeven
<geert+renesas@glider.be> wrote:
> Unlike the clocks management code for runtime PM, the code used for
> system suspend does not check the pm_clock_entry.status field.
> If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and
> ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT).
>
> Depending on the clock implementation, suspend or resume may crash with:
>
> Unable to handle kernel NULL pointer dereference at virtual address 00000026
>
> (CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable()
> only has a NULL check; pre-CCF implementations may behave differently)
>
> While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't
> hurt to use the same state machine as is done for runtime PM, as this
> makes the two versions more similar, and eligible for a future
> consolidation.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> This crash started to happen on armadillo-legacy during s2ram if
> CONFIG_PM_RUNTIME is not set after applying "[PATCH v2 07/11] ARM:
> shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support"
> (http://www.spinics.net/linux/lists/arm-kernel/msg365438.html), as
> there's no NULL clock for the HDMI device.
>
> Most existing code calling pm_clk_suspend()/pm_clk_resume() is protected
> by a check for CONFIG_PM_RUNTIME (davinci, keystone, omap1,
> drivers/sh/pm_runtime.c), so it was not affected by this bug.
>
> Exceptions are:
> - arch/arm/mach-shmobile/pm-r8a7779.c (marzen),
> - arch/arm/mach-shmobile/pm-rmobile.c (r8a7740/armadillo and
> sh7372/mackerel),
> but it's difficult to assess from the code whether the bug is really
> triggered on these platforms.
>
> Grygorii Strashko's "[PATCH v1 2/4] ARM: keystone: pm: switch to use
> generic pm domains" is not affected, as pm_clk_add_clk() is only called
> for existing clocks.
>
> If it crashes on marzen or mackerel, I think this fix needs to be
> applied to stable, too. I don't have access to marzen or mackerel boards,
> though.
>
> How to test:
> - Build a kernel with CONFIG_PM_SLEEP/CONFIG_SUSPEND enabled, but
> CONFIG_PM_RUNTIME disabled,
> - echo 0 > /sys/module/printk/parameters/console_suspend,
> - echo mem > /sys/power/state,
> - wake up using e.g. gpio-keys or serial console activity.
> ---
> drivers/base/power/clock_ops.c | 19 +++++++++++++++----
> 1 file changed, 15 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c
> index b99e6c06ee678ecb..78369305e0698109 100644
> --- a/drivers/base/power/clock_ops.c
> +++ b/drivers/base/power/clock_ops.c
> @@ -368,8 +368,13 @@ int pm_clk_suspend(struct device *dev)
>
> spin_lock_irqsave(&psd->lock, flags);
>
> - list_for_each_entry_reverse(ce, &psd->clock_list, node)
> - clk_disable(ce->clk);
> + list_for_each_entry_reverse(ce, &psd->clock_list, node) {
> + if (ce->status < PCE_STATUS_ERROR) {
> + if (ce->status == PCE_STATUS_ENABLED)
> + clk_disable(ce->clk);
> + ce->status = PCE_STATUS_ACQUIRED;
> + }
> + }
>
> spin_unlock_irqrestore(&psd->lock, flags);
>
> @@ -385,6 +390,7 @@ int pm_clk_resume(struct device *dev)
> struct pm_subsys_data *psd = dev_to_psd(dev);
> struct pm_clock_entry *ce;
> unsigned long flags;
> + int ret;
>
> dev_dbg(dev, "%s()\n", __func__);
>
> @@ -394,8 +400,13 @@ int pm_clk_resume(struct device *dev)
>
> spin_lock_irqsave(&psd->lock, flags);
>
> - list_for_each_entry(ce, &psd->clock_list, node)
> - __pm_clk_enable(dev, ce->clk);
> + list_for_each_entry(ce, &psd->clock_list, node) {
> + if (ce->status < PCE_STATUS_ERROR) {
> + ret = __pm_clk_enable(dev, ce->clk);
> + if (!ret)
> + ce->status = PCE_STATUS_ENABLED;
> + }
> + }
>
> spin_unlock_irqrestore(&psd->lock, flags);
>
> --
> 1.9.1
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
--
To unsubscribe from this list: send the line "unsubscribe linux-pm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Oct 30, 2014 at 10:06:25AM +0100, Geert Uytterhoeven wrote: > Upstream commit a968bed78b549b4c61d4a46e59161fc1f60f96a6 > Author: Geert Uytterhoeven <geert+renesas@glider.be> > Date: Wed Oct 1 20:38:17 2014 +0200 > > PM / clk: Fix crash in clocks management code if !CONFIG_PM_RUNTIME > > > Simon tried it on mackerel. It did not crash, but caused a warning and > backtrace: > > WARNING: CPU: 0 PID: 1420 at drivers/sh/clk/core.c:240 > __clk_disable+0x80/0x90() > Trying to disable clock c04bd4d8 with 0 usecount > > which got fixed by the patch. So I think it should be applied to > -stable (v3.14 and up). > Thanks, I'm queuing it for the 3.16. Cheers, -- Luís > Thanks! > > On Wed, Oct 1, 2014 at 8:38 PM, Geert Uytterhoeven > <geert+renesas@glider.be> wrote: > > Unlike the clocks management code for runtime PM, the code used for > > system suspend does not check the pm_clock_entry.status field. > > If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and > > ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT). > > > > Depending on the clock implementation, suspend or resume may crash with: > > > > Unable to handle kernel NULL pointer dereference at virtual address 00000026 > > > > (CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable() > > only has a NULL check; pre-CCF implementations may behave differently) > > > > While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't > > hurt to use the same state machine as is done for runtime PM, as this > > makes the two versions more similar, and eligible for a future > > consolidation. > > > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > > --- > > This crash started to happen on armadillo-legacy during s2ram if > > CONFIG_PM_RUNTIME is not set after applying "[PATCH v2 07/11] ARM: > > shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support" > > (http://www.spinics.net/linux/lists/arm-kernel/msg365438.html), as > > there's no NULL clock for the HDMI device. > > > > Most existing code calling pm_clk_suspend()/pm_clk_resume() is protected > > by a check for CONFIG_PM_RUNTIME (davinci, keystone, omap1, > > drivers/sh/pm_runtime.c), so it was not affected by this bug. > > > > Exceptions are: > > - arch/arm/mach-shmobile/pm-r8a7779.c (marzen), > > - arch/arm/mach-shmobile/pm-rmobile.c (r8a7740/armadillo and > > sh7372/mackerel), > > but it's difficult to assess from the code whether the bug is really > > triggered on these platforms. > > > > Grygorii Strashko's "[PATCH v1 2/4] ARM: keystone: pm: switch to use > > generic pm domains" is not affected, as pm_clk_add_clk() is only called > > for existing clocks. > > > > If it crashes on marzen or mackerel, I think this fix needs to be > > applied to stable, too. I don't have access to marzen or mackerel boards, > > though. > > > > How to test: > > - Build a kernel with CONFIG_PM_SLEEP/CONFIG_SUSPEND enabled, but > > CONFIG_PM_RUNTIME disabled, > > - echo 0 > /sys/module/printk/parameters/console_suspend, > > - echo mem > /sys/power/state, > > - wake up using e.g. gpio-keys or serial console activity. > > --- > > drivers/base/power/clock_ops.c | 19 +++++++++++++++---- > > 1 file changed, 15 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c > > index b99e6c06ee678ecb..78369305e0698109 100644 > > --- a/drivers/base/power/clock_ops.c > > +++ b/drivers/base/power/clock_ops.c > > @@ -368,8 +368,13 @@ int pm_clk_suspend(struct device *dev) > > > > spin_lock_irqsave(&psd->lock, flags); > > > > - list_for_each_entry_reverse(ce, &psd->clock_list, node) > > - clk_disable(ce->clk); > > + list_for_each_entry_reverse(ce, &psd->clock_list, node) { > > + if (ce->status < PCE_STATUS_ERROR) { > > + if (ce->status == PCE_STATUS_ENABLED) > > + clk_disable(ce->clk); > > + ce->status = PCE_STATUS_ACQUIRED; > > + } > > + } > > > > spin_unlock_irqrestore(&psd->lock, flags); > > > > @@ -385,6 +390,7 @@ int pm_clk_resume(struct device *dev) > > struct pm_subsys_data *psd = dev_to_psd(dev); > > struct pm_clock_entry *ce; > > unsigned long flags; > > + int ret; > > > > dev_dbg(dev, "%s()\n", __func__); > > > > @@ -394,8 +400,13 @@ int pm_clk_resume(struct device *dev) > > > > spin_lock_irqsave(&psd->lock, flags); > > > > - list_for_each_entry(ce, &psd->clock_list, node) > > - __pm_clk_enable(dev, ce->clk); > > + list_for_each_entry(ce, &psd->clock_list, node) { > > + if (ce->status < PCE_STATUS_ERROR) { > > + ret = __pm_clk_enable(dev, ce->clk); > > + if (!ret) > > + ce->status = PCE_STATUS_ENABLED; > > + } > > + } > > > > spin_unlock_irqrestore(&psd->lock, flags); > > > > -- > > 1.9.1 > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds > -- > To unsubscribe from this list: send the line "unsubscribe stable" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/base/power/clock_ops.c b/drivers/base/power/clock_ops.c index b99e6c06ee678ecb..78369305e0698109 100644 --- a/drivers/base/power/clock_ops.c +++ b/drivers/base/power/clock_ops.c @@ -368,8 +368,13 @@ int pm_clk_suspend(struct device *dev) spin_lock_irqsave(&psd->lock, flags); - list_for_each_entry_reverse(ce, &psd->clock_list, node) - clk_disable(ce->clk); + list_for_each_entry_reverse(ce, &psd->clock_list, node) { + if (ce->status < PCE_STATUS_ERROR) { + if (ce->status == PCE_STATUS_ENABLED) + clk_disable(ce->clk); + ce->status = PCE_STATUS_ACQUIRED; + } + } spin_unlock_irqrestore(&psd->lock, flags); @@ -385,6 +390,7 @@ int pm_clk_resume(struct device *dev) struct pm_subsys_data *psd = dev_to_psd(dev); struct pm_clock_entry *ce; unsigned long flags; + int ret; dev_dbg(dev, "%s()\n", __func__); @@ -394,8 +400,13 @@ int pm_clk_resume(struct device *dev) spin_lock_irqsave(&psd->lock, flags); - list_for_each_entry(ce, &psd->clock_list, node) - __pm_clk_enable(dev, ce->clk); + list_for_each_entry(ce, &psd->clock_list, node) { + if (ce->status < PCE_STATUS_ERROR) { + ret = __pm_clk_enable(dev, ce->clk); + if (!ret) + ce->status = PCE_STATUS_ENABLED; + } + } spin_unlock_irqrestore(&psd->lock, flags);
Unlike the clocks management code for runtime PM, the code used for system suspend does not check the pm_clock_entry.status field. If pm_clk_acquire() failed, ce->status will be PCE_STATUS_ERROR, and ce->clk will be a negative error code (e.g. 0xfffffffe = -2 = -ENOENT). Depending on the clock implementation, suspend or resume may crash with: Unable to handle kernel NULL pointer dereference at virtual address 00000026 (CCF clk_disable() has an IS_ERR_OR_NULL() check, while CCF clk_enable() only has a NULL check; pre-CCF implementations may behave differently) While just checking for PCE_STATUS_ERROR would be sufficient, it doesn't hurt to use the same state machine as is done for runtime PM, as this makes the two versions more similar, and eligible for a future consolidation. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> --- This crash started to happen on armadillo-legacy during s2ram if CONFIG_PM_RUNTIME is not set after applying "[PATCH v2 07/11] ARM: shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support" (http://www.spinics.net/linux/lists/arm-kernel/msg365438.html), as there's no NULL clock for the HDMI device. Most existing code calling pm_clk_suspend()/pm_clk_resume() is protected by a check for CONFIG_PM_RUNTIME (davinci, keystone, omap1, drivers/sh/pm_runtime.c), so it was not affected by this bug. Exceptions are: - arch/arm/mach-shmobile/pm-r8a7779.c (marzen), - arch/arm/mach-shmobile/pm-rmobile.c (r8a7740/armadillo and sh7372/mackerel), but it's difficult to assess from the code whether the bug is really triggered on these platforms. Grygorii Strashko's "[PATCH v1 2/4] ARM: keystone: pm: switch to use generic pm domains" is not affected, as pm_clk_add_clk() is only called for existing clocks. If it crashes on marzen or mackerel, I think this fix needs to be applied to stable, too. I don't have access to marzen or mackerel boards, though. How to test: - Build a kernel with CONFIG_PM_SLEEP/CONFIG_SUSPEND enabled, but CONFIG_PM_RUNTIME disabled, - echo 0 > /sys/module/printk/parameters/console_suspend, - echo mem > /sys/power/state, - wake up using e.g. gpio-keys or serial console activity. --- drivers/base/power/clock_ops.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-)