user/sven/linux.git/drivers/base/power, branch v4.14.186

PM: core: Fix handling of devices deleted during system-wide resume

2020-02-14T21:32:13Z

commit 0552e05fdfea191a2cf3a0abd33574b5ef9ca818 upstream. If a device is deleted by one of its system-wide resume callbacks (for example, because it does not appear to be present or accessible any more) along with its children, the resume of the children may continue leading to use-after-free errors and other issues (potentially). Namely, if the device's children are resumed asynchronously, their resume may have been scheduled already before the device's callback runs and so the device may be deleted while dpm_wait_for_superior() is being executed for them. The memory taken up by the parent device object may be freed then while dpm_wait() is waiting for the parent's resume callback to complete, which leads to a use-after-free. Moreover, the resume of the children is really not expected to continue after they have been unregistered, so it must be terminated right away in that case. To address this problem, modify dpm_wait_for_superior() to check if the target device is still there in the system-wide PM list of devices and if so, to increment its parent's reference counter, both under dpm_list_mtx which prevents device_del() running for the child from dropping the parent's reference counter prematurely. If the device is not present in the system-wide PM list of devices any more, the resume of it cannot continue, so check that again after dpm_wait() returns, which means that the parent's callback has been completed, and pass the result of that check to the caller of dpm_wait_for_superior() to allow it to abort the device's resume if it is not there any more. Link: https://lore.kernel.org/linux-pm/1579568452-27253-1-git-send-email-chanho.min@lge.com Reported-by: Chanho Min Cc: All applicable Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

PM: sleep: Fix possible overflow in pm_system_cancel_wakeup()

2020-01-27T13:46:40Z

[ Upstream commit 2933954b71f10d392764f95eec0f0aa2d103054b ] It is not actually guaranteed that pm_abort_suspend will be nonzero when pm_system_cancel_wakeup() is called which may lead to subtle issues, so make it use atomic_dec_if_positive() instead of atomic_dec() for the safety sake. Fixes: 33e4f80ee69b ("ACPI / PM: Ignore spurious SCI wakeups from suspend-to-idle") Signed-off-by: Rafael J. Wysocki Acked-by: Thomas Gleixner Signed-off-by: Sasha Levin

PM / Domains: Deal with multiple states but no governor in genpd

2019-12-01T08:13:38Z

[ Upstream commit 2c9b7f8772033cc8bafbd4eefe2ca605bf3eb094 ] A caller of pm_genpd_init() that provides some states for the genpd via the ->states pointer in the struct generic_pm_domain, should also provide a governor. This because it's the job of the governor to pick a state that satisfies the constraints. Therefore, let's print a warning to inform the user about such bogus configuration and avoid to bail out, by instead picking the shallowest state before genpd invokes the ->power_off() callback. Signed-off-by: Ulf Hansson Reviewed-by: Lina Iyer Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

Revert "OPP: Protect dev_list with opp_table lock"

2019-11-24T07:22:45Z

This reverts commit 714ab224a8db6e8255c61a42613de9349ceb0bba which is commit 3d2556992a878a2210d3be498416aee39e0c32aa upstream. Turns out to break the build on the odroid machines, so it needs to be reverted. Reported-by: Viresh Kumar Reported-by: "kernelci.org bot" Cc: Niklas Cassel Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

OPP: Protect dev_list with opp_table lock

2019-11-20T17:00:13Z

[ Upstream commit 3d2556992a878a2210d3be498416aee39e0c32aa ] The dev_list needs to be protected with a lock, else we may have simultaneous access (addition/removal) to it and that would be racy. Extend scope of the opp_table lock to protect dev_list as well. Tested-by: Niklas Cassel Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin

PM / core: Propagate dev->power.wakeup_path when no callbacks

2019-05-31T13:47:28Z

[ Upstream commit dc351d4c5f4fe4d0f274d6d660227be0c3a03317 ] The dev->power.direct_complete flag may become set in device_prepare() in case the device don't have any PM callbacks (dev->power.no_pm_callbacks is set). This leads to a broken behaviour, when there is child having wakeup enabled and relies on its parent to be used in the wakeup path. More precisely, when the direct complete path becomes selected for the child in __device_suspend(), the propagation of the dev->power.wakeup_path becomes skipped as well. Let's address this problem, by checking if the device is a part the wakeup path or has wakeup enabled, then prevent the direct complete path from being used. Reported-by: Loic Pallardy Signed-off-by: Ulf Hansson [ rjw: Comment cleanup ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin

PM / wakeup: Rework wakeup source timer cancellation

2019-03-23T13:35:29Z

commit 1fad17fb1bbcd73159c2b992668a6957ecc5af8a upstream. If wakeup_source_add() is called right after wakeup_source_remove() for the same wakeup source, timer_setup() may be called for a potentially scheduled timer which is incorrect. To avoid that, move the wakeup source timer cancellation from wakeup_source_drop() to wakeup_source_remove(). Moreover, make wakeup_source_remove() clear the timer function after canceling the timer to let wakeup_source_not_registered() treat unregistered wakeup sources in the same way as the ones that have never been registered. Signed-off-by: Viresh Kumar Cc: 4.4+ # 4.4+ [ rjw: Subject, changelog, merged two patches together ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

OPP: Use opp_table->regulators to verify no regulator case

2019-02-12T18:46:03Z

[ Upstream commit 90e3577b5feb42bac1269e16bb3d2bdd8f6df40f ] The value of opp_table->regulator_count is not very consistent right now and it may end up being 0 while we do have a "opp-microvolt" property in the OPP table. It was kept that way as we used to check if any regulators are set with the OPP core for a device or not using value of regulator_count. Lets use opp_table->regulators for that purpose as the meaning of regulator_count is going to change in the later patches. Reported-by: Quentin Perret Signed-off-by: Viresh Kumar Signed-off-by: Sasha Levin

PM / core: Clear the direct_complete flag on errors

2018-10-13T07:27:25Z

commit 69e445ab8b66a9f30519842ef18be555d3ee9b51 upstream. If __device_suspend() runs asynchronously (in which case the device passed to it is in dpm_suspended_list at that point) and it returns early on an error or pending wakeup, and the power.direct_complete flag has been set for the device already, the subsequent device_resume() will be confused by that and it will call pm_runtime_enable() incorrectly, as runtime PM has not been disabled for the device by __device_suspend(). To avoid that, clear power.direct_complete if __device_suspend() is not going to disable runtime PM for the device before returning. Fixes: aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily) Reported-by: Al Cooper Tested-by: Al Cooper Reviewed-by: Ulf Hansson Cc: 3.16+ # 3.16+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / clk: signedness bug in of_pm_clk_add_clks()

2018-09-05T07:26:42Z

commit 5e2e2f9f76e157063a656351728703cb02b068f1 upstream. "count" needs to be signed for the error handling to work. I made "i" signed as well so they match. Fixes: 02113ba93ea4 (PM / clk: Add support for obtaining clocks from device-tree) Cc: 4.6+ # 4.6+ Signed-off-by: Dan Carpenter Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman