diff mbox series

[v3,1/3] scsi: ufs: Serialize eh_work with system PM events and async scan

Message ID 1605596660-2987-2-git-send-email-cang@codeaurora.org (mailing list archive)
State Superseded
Headers show
Series Fix some racing problems btw err_handler and paths like system PM ops and the task abort callback | expand

Commit Message

Can Guo Nov. 17, 2020, 7:04 a.m. UTC
Serialize eh_work with system PM events and async scan to make sure eh_work
does not run in parallel with them.

Signed-off-by: Can Guo <cang@codeaurora.org>
---
 drivers/scsi/ufs/ufshcd.c | 64 +++++++++++++++++++++++++++++------------------
 drivers/scsi/ufs/ufshcd.h |  1 +
 2 files changed, 41 insertions(+), 24 deletions(-)

Comments

hongwus@codeaurora.org Nov. 25, 2020, 2:48 a.m. UTC | #1
On 2020-11-17 15:04, Can Guo wrote:
> Serialize eh_work with system PM events and async scan to make sure 
> eh_work
> does not run in parallel with them.
> 
> Signed-off-by: Can Guo <cang@codeaurora.org>
> ---
>  drivers/scsi/ufs/ufshcd.c | 64 
> +++++++++++++++++++++++++++++------------------
>  drivers/scsi/ufs/ufshcd.h |  1 +
>  2 files changed, 41 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 1d8134e..7e764e8 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5597,7 +5597,9 @@ static inline void
> ufshcd_schedule_eh_work(struct ufs_hba *hba)
>  static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
>  {
>  	pm_runtime_get_sync(hba->dev);
> -	if (pm_runtime_suspended(hba->dev)) {
> +	if (pm_runtime_status_suspended(hba->dev) || hba->is_sys_suspended) {
> +		enum ufs_pm_op pm_op;
> +
>  		/*
>  		 * Don't assume anything of pm_runtime_get_sync(), if
>  		 * resume fails, irq and clocks can be OFF, and powers
> @@ -5612,7 +5614,8 @@ static void ufshcd_err_handling_prepare(struct
> ufs_hba *hba)
>  		if (!ufshcd_is_clkgating_allowed(hba))
>  			ufshcd_setup_clocks(hba, true);
>  		ufshcd_release(hba);
> -		ufshcd_vops_resume(hba, UFS_RUNTIME_PM);
> +		pm_op = hba->is_sys_suspended ? UFS_RUNTIME_PM : UFS_SYSTEM_PM;
> +		ufshcd_vops_resume(hba, pm_op);
>  	} else {
>  		ufshcd_hold(hba, false);
>  		if (hba->clk_scaling.is_allowed) {
> @@ -5633,7 +5636,7 @@ static void ufshcd_err_handling_unprepare(struct
> ufs_hba *hba)
> 
>  static inline bool ufshcd_err_handling_should_stop(struct ufs_hba 
> *hba)
>  {
> -	return (hba->ufshcd_state == UFSHCD_STATE_ERROR ||
> +	return (!hba->is_powered || hba->ufshcd_state == UFSHCD_STATE_ERROR 
> ||
>  		(!(hba->saved_err || hba->saved_uic_err || hba->force_reset ||
>  			ufshcd_is_link_broken(hba))));
>  }
> @@ -5646,6 +5649,7 @@ static void ufshcd_recover_pm_error(struct 
> ufs_hba *hba)
>  	struct request_queue *q;
>  	int ret;
> 
> +	hba->is_sys_suspended = false;
>  	/*
>  	 * Set RPM status of hba device to RPM_ACTIVE,
>  	 * this also clears its runtime error.
> @@ -5704,11 +5708,13 @@ static void ufshcd_err_handler(struct 
> work_struct *work)
> 
>  	hba = container_of(work, struct ufs_hba, eh_work);
> 
> +	down(&hba->eh_sem);
>  	spin_lock_irqsave(hba->host->host_lock, flags);
>  	if (ufshcd_err_handling_should_stop(hba)) {
>  		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
>  			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
>  		spin_unlock_irqrestore(hba->host->host_lock, flags);
> +		up(&hba->eh_sem);
>  		return;
>  	}
>  	ufshcd_set_eh_in_progress(hba);
> @@ -5716,20 +5722,18 @@ static void ufshcd_err_handler(struct 
> work_struct *work)
>  	ufshcd_err_handling_prepare(hba);
>  	spin_lock_irqsave(hba->host->host_lock, flags);
>  	ufshcd_scsi_block_requests(hba);
> -	/*
> -	 * A full reset and restore might have happened after preparation
> -	 * is finished, double check whether we should stop.
> -	 */
> -	if (ufshcd_err_handling_should_stop(hba)) {
> -		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
> -			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> -		goto out;
> -	}
>  	hba->ufshcd_state = UFSHCD_STATE_RESET;
> 
>  	/* Complete requests that have door-bell cleared by h/w */
>  	ufshcd_complete_requests(hba);
> 
> +	/*
> +	 * A full reset and restore might have happened after preparation
> +	 * is finished, double check whether we should stop.
> +	 */
> +	if (ufshcd_err_handling_should_stop(hba))
> +		goto skip_err_handling;
> +
>  	if (hba->dev_quirks & UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS) {
>  		bool ret;
> 
> @@ -5737,17 +5741,10 @@ static void ufshcd_err_handler(struct 
> work_struct *work)
>  		/* release the lock as ufshcd_quirk_dl_nac_errors() may sleep */
>  		ret = ufshcd_quirk_dl_nac_errors(hba);
>  		spin_lock_irqsave(hba->host->host_lock, flags);
> -		if (!ret && !hba->force_reset && ufshcd_is_link_active(hba))
> +		if (!ret && ufshcd_err_handling_should_stop(hba))
>  			goto skip_err_handling;
>  	}
> 
> -	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> -	    ufshcd_is_saved_err_fatal(hba) ||
> -	    ((hba->saved_err & UIC_ERROR) &&
> -	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
> -				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR))))
> -		needs_reset = true;
> -
>  	if ((hba->saved_err & (INT_FATAL_ERRORS | UFSHCD_UIC_HIBERN8_MASK)) 
> ||
>  	    (hba->saved_uic_err &&
>  	     (hba->saved_uic_err != UFSHCD_UIC_PA_GENERIC_ERROR))) {
> @@ -5767,8 +5764,14 @@ static void ufshcd_err_handler(struct 
> work_struct *work)
>  	 * transfers forcefully because they will get cleared during
>  	 * host reset and restore
>  	 */
> -	if (needs_reset)
> +	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> +	    ufshcd_is_saved_err_fatal(hba) ||
> +	    ((hba->saved_err & UIC_ERROR) &&
> +	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
> +				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) {
> +		needs_reset = true;
>  		goto do_reset;
> +	}
> 
>  	/*
>  	 * If LINERESET was caught, UFS might have been put to PWM mode,
> @@ -5876,12 +5879,11 @@ static void ufshcd_err_handler(struct 
> work_struct *work)
>  			dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x 
> saved_uic_err 0x%x",
>  			    __func__, hba->saved_err, hba->saved_uic_err);
>  	}
> -
> -out:
>  	ufshcd_clear_eh_in_progress(hba);
>  	spin_unlock_irqrestore(hba->host->host_lock, flags);
>  	ufshcd_scsi_unblock_requests(hba);
>  	ufshcd_err_handling_unprepare(hba);
> +	up(&hba->eh_sem);
>  }
> 
>  /**
> @@ -6856,6 +6858,7 @@ static int ufshcd_reset_and_restore(struct 
> ufs_hba *hba)
>  	 */
>  	scsi_report_bus_reset(hba->host, 0);
>  	if (err) {
> +		hba->ufshcd_state = UFSHCD_STATE_ERROR;
>  		hba->saved_err |= saved_err;
>  		hba->saved_uic_err |= saved_uic_err;
>  	}
> @@ -7704,8 +7707,10 @@ static void ufshcd_async_scan(void *data,
> async_cookie_t cookie)
>  	struct ufs_hba *hba = (struct ufs_hba *)data;
>  	int ret;
> 
> +	down(&hba->eh_sem);
>  	/* Initialize hba, detect and initialize UFS device */
>  	ret = ufshcd_probe_hba(hba, true);
> +	up(&hba->eh_sem);
>  	if (ret)
>  		goto out;
> 
> @@ -8718,6 +8723,7 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
>  	int ret = 0;
>  	ktime_t start = ktime_get();
> 
> +	down(&hba->eh_sem);
>  	if (!hba || !hba->is_powered)
>  		return 0;
> 
> @@ -8748,6 +8754,8 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
>  		hba->curr_dev_pwr_mode, hba->uic_link_state);
>  	if (!ret)
>  		hba->is_sys_suspended = true;
> +	else
> +		up(&hba->eh_sem);
>  	return ret;
>  }
>  EXPORT_SYMBOL(ufshcd_system_suspend);
> @@ -8764,8 +8772,10 @@ int ufshcd_system_resume(struct ufs_hba *hba)
>  	int ret = 0;
>  	ktime_t start = ktime_get();
> 
> -	if (!hba)
> +	if (!hba) {
> +		up(&hba->eh_sem);
>  		return -EINVAL;
> +	}
> 
>  	if (!hba->is_powered || pm_runtime_suspended(hba->dev))
>  		/*
> @@ -8781,6 +8791,7 @@ int ufshcd_system_resume(struct ufs_hba *hba)
>  		hba->curr_dev_pwr_mode, hba->uic_link_state);
>  	if (!ret)
>  		hba->is_sys_suspended = false;
> +	up(&hba->eh_sem);
>  	return ret;
>  }
>  EXPORT_SYMBOL(ufshcd_system_resume);
> @@ -8872,6 +8883,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
>  {
>  	int ret = 0;
> 
> +	down(&hba->eh_sem);
>  	if (!hba->is_powered)
>  		goto out;
> 
> @@ -8888,6 +8900,8 @@ int ufshcd_shutdown(struct ufs_hba *hba)
>  out:
>  	if (ret)
>  		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
> +	hba->is_powered = false;
> +	up(&hba->eh_sem);
>  	/* allow force shutdown even in case of errors */
>  	return 0;
>  }
> @@ -9082,6 +9096,8 @@ int ufshcd_init(struct ufs_hba *hba, void
> __iomem *mmio_base, unsigned int irq)
>  	INIT_WORK(&hba->eh_work, ufshcd_err_handler);
>  	INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler);
> 
> +	sema_init(&hba->eh_sem, 1);
> +
>  	/* Initialize UIC command mutex */
>  	mutex_init(&hba->uic_cmd_mutex);
> 
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 47eb143..1e680bf 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -728,6 +728,7 @@ struct ufs_hba {
>  	u32 intr_mask;
>  	u16 ee_ctrl_mask;
>  	bool is_powered;
> +	struct semaphore eh_sem;
> 
>  	/* Work Queues */
>  	struct workqueue_struct *eh_wq;

Reviewed-by: Hongwu Su<hongwus@codeaurora.org>
Asutosh Das (asd) Dec. 1, 2020, 2:41 a.m. UTC | #2
On 11/16/2020 11:04 PM, Can Guo wrote:
> Serialize eh_work with system PM events and async scan to make sure eh_work
> does not run in parallel with them.
> 
> Signed-off-by: Can Guo <cang@codeaurora.org>
> ---

Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>

>   drivers/scsi/ufs/ufshcd.c | 64 +++++++++++++++++++++++++++++------------------
>   drivers/scsi/ufs/ufshcd.h |  1 +
>   2 files changed, 41 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index 1d8134e..7e764e8 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -5597,7 +5597,9 @@ static inline void ufshcd_schedule_eh_work(struct ufs_hba *hba)
>   static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
>   {
>   	pm_runtime_get_sync(hba->dev);
> -	if (pm_runtime_suspended(hba->dev)) {
> +	if (pm_runtime_status_suspended(hba->dev) || hba->is_sys_suspended) {
> +		enum ufs_pm_op pm_op;
> +
>   		/*
>   		 * Don't assume anything of pm_runtime_get_sync(), if
>   		 * resume fails, irq and clocks can be OFF, and powers
> @@ -5612,7 +5614,8 @@ static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
>   		if (!ufshcd_is_clkgating_allowed(hba))
>   			ufshcd_setup_clocks(hba, true);
>   		ufshcd_release(hba);
> -		ufshcd_vops_resume(hba, UFS_RUNTIME_PM);
> +		pm_op = hba->is_sys_suspended ? UFS_RUNTIME_PM : UFS_SYSTEM_PM;
> +		ufshcd_vops_resume(hba, pm_op);
>   	} else {
>   		ufshcd_hold(hba, false);
>   		if (hba->clk_scaling.is_allowed) {
> @@ -5633,7 +5636,7 @@ static void ufshcd_err_handling_unprepare(struct ufs_hba *hba)
>   
>   static inline bool ufshcd_err_handling_should_stop(struct ufs_hba *hba)
>   {
> -	return (hba->ufshcd_state == UFSHCD_STATE_ERROR ||
> +	return (!hba->is_powered || hba->ufshcd_state == UFSHCD_STATE_ERROR ||
>   		(!(hba->saved_err || hba->saved_uic_err || hba->force_reset ||
>   			ufshcd_is_link_broken(hba))));
>   }
> @@ -5646,6 +5649,7 @@ static void ufshcd_recover_pm_error(struct ufs_hba *hba)
>   	struct request_queue *q;
>   	int ret;
>   
> +	hba->is_sys_suspended = false;
>   	/*
>   	 * Set RPM status of hba device to RPM_ACTIVE,
>   	 * this also clears its runtime error.
> @@ -5704,11 +5708,13 @@ static void ufshcd_err_handler(struct work_struct *work)
>   
>   	hba = container_of(work, struct ufs_hba, eh_work);
>   
> +	down(&hba->eh_sem);
>   	spin_lock_irqsave(hba->host->host_lock, flags);
>   	if (ufshcd_err_handling_should_stop(hba)) {
>   		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
>   			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
>   		spin_unlock_irqrestore(hba->host->host_lock, flags);
> +		up(&hba->eh_sem);
>   		return;
>   	}
>   	ufshcd_set_eh_in_progress(hba);
> @@ -5716,20 +5722,18 @@ static void ufshcd_err_handler(struct work_struct *work)
>   	ufshcd_err_handling_prepare(hba);
>   	spin_lock_irqsave(hba->host->host_lock, flags);
>   	ufshcd_scsi_block_requests(hba);
> -	/*
> -	 * A full reset and restore might have happened after preparation
> -	 * is finished, double check whether we should stop.
> -	 */
> -	if (ufshcd_err_handling_should_stop(hba)) {
> -		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
> -			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> -		goto out;
> -	}
>   	hba->ufshcd_state = UFSHCD_STATE_RESET;
>   
>   	/* Complete requests that have door-bell cleared by h/w */
>   	ufshcd_complete_requests(hba);
>   
> +	/*
> +	 * A full reset and restore might have happened after preparation
> +	 * is finished, double check whether we should stop.
> +	 */
> +	if (ufshcd_err_handling_should_stop(hba))
> +		goto skip_err_handling;
> +
>   	if (hba->dev_quirks & UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS) {
>   		bool ret;
>   
> @@ -5737,17 +5741,10 @@ static void ufshcd_err_handler(struct work_struct *work)
>   		/* release the lock as ufshcd_quirk_dl_nac_errors() may sleep */
>   		ret = ufshcd_quirk_dl_nac_errors(hba);
>   		spin_lock_irqsave(hba->host->host_lock, flags);
> -		if (!ret && !hba->force_reset && ufshcd_is_link_active(hba))
> +		if (!ret && ufshcd_err_handling_should_stop(hba))
>   			goto skip_err_handling;
>   	}
>   
> -	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> -	    ufshcd_is_saved_err_fatal(hba) ||
> -	    ((hba->saved_err & UIC_ERROR) &&
> -	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
> -				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR))))
> -		needs_reset = true;
> -
>   	if ((hba->saved_err & (INT_FATAL_ERRORS | UFSHCD_UIC_HIBERN8_MASK)) ||
>   	    (hba->saved_uic_err &&
>   	     (hba->saved_uic_err != UFSHCD_UIC_PA_GENERIC_ERROR))) {
> @@ -5767,8 +5764,14 @@ static void ufshcd_err_handler(struct work_struct *work)
>   	 * transfers forcefully because they will get cleared during
>   	 * host reset and restore
>   	 */
> -	if (needs_reset)
> +	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> +	    ufshcd_is_saved_err_fatal(hba) ||
> +	    ((hba->saved_err & UIC_ERROR) &&
> +	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
> +				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) {
> +		needs_reset = true;
>   		goto do_reset;
> +	}
>   
>   	/*
>   	 * If LINERESET was caught, UFS might have been put to PWM mode,
> @@ -5876,12 +5879,11 @@ static void ufshcd_err_handler(struct work_struct *work)
>   			dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x saved_uic_err 0x%x",
>   			    __func__, hba->saved_err, hba->saved_uic_err);
>   	}
> -
> -out:
>   	ufshcd_clear_eh_in_progress(hba);
>   	spin_unlock_irqrestore(hba->host->host_lock, flags);
>   	ufshcd_scsi_unblock_requests(hba);
>   	ufshcd_err_handling_unprepare(hba);
> +	up(&hba->eh_sem);
>   }
>   
>   /**
> @@ -6856,6 +6858,7 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
>   	 */
>   	scsi_report_bus_reset(hba->host, 0);
>   	if (err) {
> +		hba->ufshcd_state = UFSHCD_STATE_ERROR;
>   		hba->saved_err |= saved_err;
>   		hba->saved_uic_err |= saved_uic_err;
>   	}
> @@ -7704,8 +7707,10 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie)
>   	struct ufs_hba *hba = (struct ufs_hba *)data;
>   	int ret;
>   
> +	down(&hba->eh_sem);
>   	/* Initialize hba, detect and initialize UFS device */
>   	ret = ufshcd_probe_hba(hba, true);
> +	up(&hba->eh_sem);
>   	if (ret)
>   		goto out;
>   
> @@ -8718,6 +8723,7 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
>   	int ret = 0;
>   	ktime_t start = ktime_get();
>   
> +	down(&hba->eh_sem);
>   	if (!hba || !hba->is_powered)
>   		return 0;
>   
> @@ -8748,6 +8754,8 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
>   		hba->curr_dev_pwr_mode, hba->uic_link_state);
>   	if (!ret)
>   		hba->is_sys_suspended = true;
> +	else
> +		up(&hba->eh_sem);
>   	return ret;
>   }
>   EXPORT_SYMBOL(ufshcd_system_suspend);
> @@ -8764,8 +8772,10 @@ int ufshcd_system_resume(struct ufs_hba *hba)
>   	int ret = 0;
>   	ktime_t start = ktime_get();
>   
> -	if (!hba)
> +	if (!hba) {
> +		up(&hba->eh_sem);
>   		return -EINVAL;
> +	}
>   
>   	if (!hba->is_powered || pm_runtime_suspended(hba->dev))
>   		/*
> @@ -8781,6 +8791,7 @@ int ufshcd_system_resume(struct ufs_hba *hba)
>   		hba->curr_dev_pwr_mode, hba->uic_link_state);
>   	if (!ret)
>   		hba->is_sys_suspended = false;
> +	up(&hba->eh_sem);
>   	return ret;
>   }
>   EXPORT_SYMBOL(ufshcd_system_resume);
> @@ -8872,6 +8883,7 @@ int ufshcd_shutdown(struct ufs_hba *hba)
>   {
>   	int ret = 0;
>   
> +	down(&hba->eh_sem);
>   	if (!hba->is_powered)
>   		goto out;
>   
> @@ -8888,6 +8900,8 @@ int ufshcd_shutdown(struct ufs_hba *hba)
>   out:
>   	if (ret)
>   		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
> +	hba->is_powered = false;
> +	up(&hba->eh_sem);
>   	/* allow force shutdown even in case of errors */
>   	return 0;
>   }
> @@ -9082,6 +9096,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
>   	INIT_WORK(&hba->eh_work, ufshcd_err_handler);
>   	INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler);
>   
> +	sema_init(&hba->eh_sem, 1);
> +
>   	/* Initialize UIC command mutex */
>   	mutex_init(&hba->uic_cmd_mutex);
>   
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 47eb143..1e680bf 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -728,6 +728,7 @@ struct ufs_hba {
>   	u32 intr_mask;
>   	u16 ee_ctrl_mask;
>   	bool is_powered;
> +	struct semaphore eh_sem;
>   
>   	/* Work Queues */
>   	struct workqueue_struct *eh_wq;
>
diff mbox series

Patch

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 1d8134e..7e764e8 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -5597,7 +5597,9 @@  static inline void ufshcd_schedule_eh_work(struct ufs_hba *hba)
 static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
 {
 	pm_runtime_get_sync(hba->dev);
-	if (pm_runtime_suspended(hba->dev)) {
+	if (pm_runtime_status_suspended(hba->dev) || hba->is_sys_suspended) {
+		enum ufs_pm_op pm_op;
+
 		/*
 		 * Don't assume anything of pm_runtime_get_sync(), if
 		 * resume fails, irq and clocks can be OFF, and powers
@@ -5612,7 +5614,8 @@  static void ufshcd_err_handling_prepare(struct ufs_hba *hba)
 		if (!ufshcd_is_clkgating_allowed(hba))
 			ufshcd_setup_clocks(hba, true);
 		ufshcd_release(hba);
-		ufshcd_vops_resume(hba, UFS_RUNTIME_PM);
+		pm_op = hba->is_sys_suspended ? UFS_RUNTIME_PM : UFS_SYSTEM_PM;
+		ufshcd_vops_resume(hba, pm_op);
 	} else {
 		ufshcd_hold(hba, false);
 		if (hba->clk_scaling.is_allowed) {
@@ -5633,7 +5636,7 @@  static void ufshcd_err_handling_unprepare(struct ufs_hba *hba)
 
 static inline bool ufshcd_err_handling_should_stop(struct ufs_hba *hba)
 {
-	return (hba->ufshcd_state == UFSHCD_STATE_ERROR ||
+	return (!hba->is_powered || hba->ufshcd_state == UFSHCD_STATE_ERROR ||
 		(!(hba->saved_err || hba->saved_uic_err || hba->force_reset ||
 			ufshcd_is_link_broken(hba))));
 }
@@ -5646,6 +5649,7 @@  static void ufshcd_recover_pm_error(struct ufs_hba *hba)
 	struct request_queue *q;
 	int ret;
 
+	hba->is_sys_suspended = false;
 	/*
 	 * Set RPM status of hba device to RPM_ACTIVE,
 	 * this also clears its runtime error.
@@ -5704,11 +5708,13 @@  static void ufshcd_err_handler(struct work_struct *work)
 
 	hba = container_of(work, struct ufs_hba, eh_work);
 
+	down(&hba->eh_sem);
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	if (ufshcd_err_handling_should_stop(hba)) {
 		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
 			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
 		spin_unlock_irqrestore(hba->host->host_lock, flags);
+		up(&hba->eh_sem);
 		return;
 	}
 	ufshcd_set_eh_in_progress(hba);
@@ -5716,20 +5722,18 @@  static void ufshcd_err_handler(struct work_struct *work)
 	ufshcd_err_handling_prepare(hba);
 	spin_lock_irqsave(hba->host->host_lock, flags);
 	ufshcd_scsi_block_requests(hba);
-	/*
-	 * A full reset and restore might have happened after preparation
-	 * is finished, double check whether we should stop.
-	 */
-	if (ufshcd_err_handling_should_stop(hba)) {
-		if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
-			hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
-		goto out;
-	}
 	hba->ufshcd_state = UFSHCD_STATE_RESET;
 
 	/* Complete requests that have door-bell cleared by h/w */
 	ufshcd_complete_requests(hba);
 
+	/*
+	 * A full reset and restore might have happened after preparation
+	 * is finished, double check whether we should stop.
+	 */
+	if (ufshcd_err_handling_should_stop(hba))
+		goto skip_err_handling;
+
 	if (hba->dev_quirks & UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS) {
 		bool ret;
 
@@ -5737,17 +5741,10 @@  static void ufshcd_err_handler(struct work_struct *work)
 		/* release the lock as ufshcd_quirk_dl_nac_errors() may sleep */
 		ret = ufshcd_quirk_dl_nac_errors(hba);
 		spin_lock_irqsave(hba->host->host_lock, flags);
-		if (!ret && !hba->force_reset && ufshcd_is_link_active(hba))
+		if (!ret && ufshcd_err_handling_should_stop(hba))
 			goto skip_err_handling;
 	}
 
-	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
-	    ufshcd_is_saved_err_fatal(hba) ||
-	    ((hba->saved_err & UIC_ERROR) &&
-	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
-				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR))))
-		needs_reset = true;
-
 	if ((hba->saved_err & (INT_FATAL_ERRORS | UFSHCD_UIC_HIBERN8_MASK)) ||
 	    (hba->saved_uic_err &&
 	     (hba->saved_uic_err != UFSHCD_UIC_PA_GENERIC_ERROR))) {
@@ -5767,8 +5764,14 @@  static void ufshcd_err_handler(struct work_struct *work)
 	 * transfers forcefully because they will get cleared during
 	 * host reset and restore
 	 */
-	if (needs_reset)
+	if (hba->force_reset || ufshcd_is_link_broken(hba) ||
+	    ufshcd_is_saved_err_fatal(hba) ||
+	    ((hba->saved_err & UIC_ERROR) &&
+	     (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR |
+				    UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) {
+		needs_reset = true;
 		goto do_reset;
+	}
 
 	/*
 	 * If LINERESET was caught, UFS might have been put to PWM mode,
@@ -5876,12 +5879,11 @@  static void ufshcd_err_handler(struct work_struct *work)
 			dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x saved_uic_err 0x%x",
 			    __func__, hba->saved_err, hba->saved_uic_err);
 	}
-
-out:
 	ufshcd_clear_eh_in_progress(hba);
 	spin_unlock_irqrestore(hba->host->host_lock, flags);
 	ufshcd_scsi_unblock_requests(hba);
 	ufshcd_err_handling_unprepare(hba);
+	up(&hba->eh_sem);
 }
 
 /**
@@ -6856,6 +6858,7 @@  static int ufshcd_reset_and_restore(struct ufs_hba *hba)
 	 */
 	scsi_report_bus_reset(hba->host, 0);
 	if (err) {
+		hba->ufshcd_state = UFSHCD_STATE_ERROR;
 		hba->saved_err |= saved_err;
 		hba->saved_uic_err |= saved_uic_err;
 	}
@@ -7704,8 +7707,10 @@  static void ufshcd_async_scan(void *data, async_cookie_t cookie)
 	struct ufs_hba *hba = (struct ufs_hba *)data;
 	int ret;
 
+	down(&hba->eh_sem);
 	/* Initialize hba, detect and initialize UFS device */
 	ret = ufshcd_probe_hba(hba, true);
+	up(&hba->eh_sem);
 	if (ret)
 		goto out;
 
@@ -8718,6 +8723,7 @@  int ufshcd_system_suspend(struct ufs_hba *hba)
 	int ret = 0;
 	ktime_t start = ktime_get();
 
+	down(&hba->eh_sem);
 	if (!hba || !hba->is_powered)
 		return 0;
 
@@ -8748,6 +8754,8 @@  int ufshcd_system_suspend(struct ufs_hba *hba)
 		hba->curr_dev_pwr_mode, hba->uic_link_state);
 	if (!ret)
 		hba->is_sys_suspended = true;
+	else
+		up(&hba->eh_sem);
 	return ret;
 }
 EXPORT_SYMBOL(ufshcd_system_suspend);
@@ -8764,8 +8772,10 @@  int ufshcd_system_resume(struct ufs_hba *hba)
 	int ret = 0;
 	ktime_t start = ktime_get();
 
-	if (!hba)
+	if (!hba) {
+		up(&hba->eh_sem);
 		return -EINVAL;
+	}
 
 	if (!hba->is_powered || pm_runtime_suspended(hba->dev))
 		/*
@@ -8781,6 +8791,7 @@  int ufshcd_system_resume(struct ufs_hba *hba)
 		hba->curr_dev_pwr_mode, hba->uic_link_state);
 	if (!ret)
 		hba->is_sys_suspended = false;
+	up(&hba->eh_sem);
 	return ret;
 }
 EXPORT_SYMBOL(ufshcd_system_resume);
@@ -8872,6 +8883,7 @@  int ufshcd_shutdown(struct ufs_hba *hba)
 {
 	int ret = 0;
 
+	down(&hba->eh_sem);
 	if (!hba->is_powered)
 		goto out;
 
@@ -8888,6 +8900,8 @@  int ufshcd_shutdown(struct ufs_hba *hba)
 out:
 	if (ret)
 		dev_err(hba->dev, "%s failed, err %d\n", __func__, ret);
+	hba->is_powered = false;
+	up(&hba->eh_sem);
 	/* allow force shutdown even in case of errors */
 	return 0;
 }
@@ -9082,6 +9096,8 @@  int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq)
 	INIT_WORK(&hba->eh_work, ufshcd_err_handler);
 	INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler);
 
+	sema_init(&hba->eh_sem, 1);
+
 	/* Initialize UIC command mutex */
 	mutex_init(&hba->uic_cmd_mutex);
 
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 47eb143..1e680bf 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -728,6 +728,7 @@  struct ufs_hba {
 	u32 intr_mask;
 	u16 ee_ctrl_mask;
 	bool is_powered;
+	struct semaphore eh_sem;
 
 	/* Work Queues */
 	struct workqueue_struct *eh_wq;