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Commitefde2659b0("drivers: qcom: rpmh-rsc: Use rcuidle tracepoints for rpmh") was written to fix a bug seen in an unmerged series that implemented a struct generic_pm_domain::power_off() callback calling rpmh_flush(). See stack trace below. Call trace: dump_backtrace+0x0/0x174 show_stack+0x20/0x2c dump_stack+0xc8/0x124 lockdep_rcu_suspicious+0xe4/0x104 __tcs_buffer_write+0x230/0x2d0 rpmh_rsc_write_ctrl_data+0x210/0x270 rpmh_flush+0x84/0x24c rpmh_domain_power_off+0x78/0x98 _genpd_power_off+0x40/0xc0 genpd_power_off+0x168/0x208 Later the final merged solution is to use CPU PM notification to invoke rpmh_flush() and power_off() callback of genpd is not implemented in the driver. CPU PM notifiers are run with RCU enabled/watching (see cpu_pm_notify() and how it calls rcu_irq_enter_irqson() before calling the notifiers). Remove this change since RCU will not be idle during CPU PM notifications hence not required to use _rcuidle tracepoint. Using _rcuidle tracepoint prevented rpmh driver to be loadable module as these are not exported symbols. This reverts commitefde2659b0. Cc: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Cc: John Stultz <john.stultz@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Maulik Shah <mkshah@codeaurora.org> Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> Link: https://lore.kernel.org/r/1601877596-32676-2-git-send-email-mkshah@codeaurora.org Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Linux kernel
============
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There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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