bus: mhi: core: Handle disable transitions in state worker (3c1bd004) · Commits · 戴 / test

Mission mode transition is handled by state worker thread but power off is not. There is a possibility while mission mode transition is in progress which calls MHI client driver probe, power off is issued by MHI controller. This results into client driver probe and remove running in parallel and causes use after free situation. By queuing disable transition work when mission mode is in progress prevents the race condition. Signed-off-by:

Hemant Kumar <hemantk@codeaurora.org> Reviewed-by:

Jeffrey Hugo <jhugo@codeaurora.org> Reviewed-by:

Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Signed-off-by:

Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> Link: https://lore.kernel.org/r/20200521170249.21795-11-manivannan.sadhasivam@linaro.org Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/bus/mhi/core/init.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -35,6 +35,7 @@ const char * const dev_state_tran_str[DEV_ST_TRANSITION_MAX] = {
		[DEV_ST_TRANSITION_SBL] = "SBL",
		[DEV_ST_TRANSITION_MISSION_MODE] = "MISSION_MODE",
		[DEV_ST_TRANSITION_SYS_ERR] = "SYS_ERR",
		[DEV_ST_TRANSITION_DISABLE] = "DISABLE",
		};

		const char * const mhi_state_str[MHI_STATE_MAX] = {

drivers/bus/mhi/core/internal.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -387,6 +387,7 @@ enum dev_st_transition {
		DEV_ST_TRANSITION_SBL,
		DEV_ST_TRANSITION_MISSION_MODE,
		DEV_ST_TRANSITION_SYS_ERR,
		DEV_ST_TRANSITION_DISABLE,
		DEV_ST_TRANSITION_MAX,
		};

drivers/bus/mhi/core/pm.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -657,6 +657,10 @@ void mhi_pm_st_worker(struct work_struct *work)
		mhi_pm_disable_transition
		(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS);
		break;
		case DEV_ST_TRANSITION_DISABLE:
		mhi_pm_disable_transition
		(mhi_cntrl, MHI_PM_SHUTDOWN_PROCESS);
		break;
		default:
		break;
		}
		@@ -1011,7 +1015,12 @@ void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful)
		to_mhi_pm_state_str(MHI_PM_LD_ERR_FATAL_DETECT),
		to_mhi_pm_state_str(mhi_cntrl->pm_state));
		}
		mhi_pm_disable_transition(mhi_cntrl, MHI_PM_SHUTDOWN_PROCESS);

		mhi_queue_state_transition(mhi_cntrl, DEV_ST_TRANSITION_DISABLE);

		/* Wait for shutdown to complete */
		flush_work(&mhi_cntrl->st_worker);

		mhi_deinit_free_irq(mhi_cntrl);

		if (!mhi_cntrl->pre_init) {

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