Re: [PATCH] soc: qcom: update config dependencies for QCOM_RPMPD

[Viresh Kumar <viresh.kumar@linaro.org>]

On 22-01-19, 15:24, Rajendra Nayak wrote:
> I was doing some quick testing by adding the calls to of_genpd_remove_last() as
> suggested by Ulf for cleaning up the genpd registrations, and I run into this
> backtrace when the driver re-probes followed by a remove
> 
> [   59.204525] kobject ((____ptrval____)): tried to init an initialized object, something is seriously wr.
> [   59.214262] CPU: 3 PID: 1600 Comm: sh Not tainted 5.0.0-rc1-00012-g0513915837c5-dirty #32
> [   59.222500] Hardware name: Qualcomm Technologies, Inc. SDM845 MTP (DT)
> [   59.229081] Call trace:
> [   59.231574]  dump_backtrace+0x0/0x148
> [   59.235276]  show_stack+0x14/0x20
> [   59.238631]  dump_stack+0x8c/0xac
> [   59.241980]  kobject_init+0x8c/0xa0
> [   59.245506]  device_initialize+0x34/0xc8
> [   59.249474]  pm_genpd_init+0x170/0x260
> [   59.253261]  rpmhpd_probe+0x194/0x2b0
> [   59.256966]  platform_drv_probe+0x4c/0xa8
> [   59.261011]  really_probe+0x1e4/0x2c8
> [   59.264711]  driver_probe_device+0x58/0x10
> [   59.268927]  bind_store+0xdc/0x178
> [   59.272356]  drv_attr_store+0x20/0x30
> [   59.276061]  sysfs_kf_write+0x48/0x58
> [   59.279760]  kernfs_fop_write+0xcc/0x1c8
> [   59.283728]  __vfs_write+0x34/0x170
> [   59.287245]  vfs_write+0xa8/0x1b8
> [   59.290592]  ksys_write+0x5c/0xc8
> [   59.293941]  __arm64_sys_write+0x14/0x20
> [   59.297897]  el0_svc_common+0xb4/0x118
> [   59.301676]  el0_svc_handler+0x2c/0x80
> [   59.305455]  el0_svc+0x8/0xc
> 
> Viresh/Ulf, looks like we need some cleanup of whats done by device_initialize()
> in pm_genpd_init() to happen as part of the pm_genpd_remove()?

Yeah, we normally need to call put_device() for that. Maybe something like this:

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 500de1dee967..d5b984f042ec 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1812,6 +1812,7 @@ static int genpd_remove(struct generic_pm_domain *genpd)
        genpd_unlock(genpd);
        cancel_work_sync(&genpd->power_off_work);
        kfree(genpd->free);
+       put_device(&genpd->dev);
        pr_debug("%s: removed %s\n", __func__, genpd->name);
 
        return 0;

-- 
viresh