6.6-stable review patch. If anyone has any objections, please let me know.
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From: Rafael J. Wysocki rafael.j.wysocki@intel.com
[ Upstream commit 3775fc538f535a7c5adaf11990c7932a0bd1f9eb ]
Commit 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase") overlooked the case in which the parent of a device with DPM_FLAG_SMART_SUSPEND set did not use that flag and could be runtime- suspended before a transition into a system-wide sleep state. In that case, if the child is resumed during the subsequent transition from that state into the working state, its runtime PM status will be set to RPM_ACTIVE, but the runtime PM status of the parent will not be updated accordingly, even though the parent will be resumed too, because of the dev_pm_skip_suspend() check in device_resume_noirq().
Address this problem by tracking the need to set the runtime PM status to RPM_ACTIVE during system-wide resume transitions for devices with DPM_FLAG_SMART_SUSPEND set and all of the devices depended on by them.
Fixes: 6e176bf8d461 ("PM: sleep: core: Do not skip callbacks in the resume phase") Closes: https://lore.kernel.org/linux-pm/Z30p2Etwf3F2AUvD@hovoldconsulting.com/ Reported-by: Johan Hovold johan@kernel.org Tested-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Reviewed-by: Johan Hovold johan+linaro@kernel.org Tested-by: Johan Hovold johan+linaro@kernel.org Link: https://patch.msgid.link/12619233.O9o76ZdvQC@rjwysocki.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/base/power/main.c | 29 ++++++++++++++++++++--------- include/linux/pm.h | 1 + 2 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index fadcd0379dc2d..fd2d975de536f 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -614,13 +614,15 @@ static void device_resume_noirq(struct device *dev, pm_message_t state, bool asy * so change its status accordingly. * * Otherwise, the device is going to be resumed, so set its PM-runtime - * status to "active", but do that only if DPM_FLAG_SMART_SUSPEND is set - * to avoid confusing drivers that don't use it. + * status to "active" unless its power.set_active flag is clear, in + * which case it is not necessary to update its PM-runtime status. */ - if (skip_resume) + if (skip_resume) { pm_runtime_set_suspended(dev); - else if (dev_pm_skip_suspend(dev)) + } else if (dev->power.set_active) { pm_runtime_set_active(dev); + dev->power.set_active = false; + }
if (dev->pm_domain) { info = "noirq power domain "; @@ -1170,18 +1172,24 @@ static pm_message_t resume_event(pm_message_t sleep_state) return PMSG_ON; }
-static void dpm_superior_set_must_resume(struct device *dev) +static void dpm_superior_set_must_resume(struct device *dev, bool set_active) { struct device_link *link; int idx;
- if (dev->parent) + if (dev->parent) { dev->parent->power.must_resume = true; + if (set_active) + dev->parent->power.set_active = true; + }
idx = device_links_read_lock();
- list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) + list_for_each_entry_rcu_locked(link, &dev->links.suppliers, c_node) { link->supplier->power.must_resume = true; + if (set_active) + link->supplier->power.set_active = true; + }
device_links_read_unlock(idx); } @@ -1257,8 +1265,11 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a dev->power.may_skip_resume)) dev->power.must_resume = true;
- if (dev->power.must_resume) - dpm_superior_set_must_resume(dev); + if (dev->power.must_resume) { + dev->power.set_active = dev->power.set_active || + dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND); + dpm_superior_set_must_resume(dev, dev->power.set_active); + }
Complete: complete_all(&dev->power.completion); diff --git a/include/linux/pm.h b/include/linux/pm.h index 9e1c60cd60e5a..1ad57c98264af 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -683,6 +683,7 @@ struct dev_pm_info { bool no_pm_callbacks:1; /* Owned by the PM core */ bool async_in_progress:1; /* Owned by the PM core */ bool must_resume:1; /* Owned by the PM core */ + bool set_active:1; /* Owned by the PM core */ bool may_skip_resume:1; /* Set by subsystems */ #else bool should_wakeup:1;