Error paths in ufshcd_init() ufshcd_hba_exit() killed clk_scaling workqueue when the workqueue is actually created quite late in ufshcd_init(). So, we end up getting NULL pointer dereference in such error paths. Fix this by moving clk_scaling initialization and kill codes to two separate methods, and call them at required places. Fixes: 401f1e4490ee ("scsi: ufs: don't suspend clock scaling during clock gating") Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx> Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Cc: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx> Cc: Matthias Kaehlcke <mka@xxxxxxxxxxxx> Cc: Evan Green <evgreen@xxxxxxxxxxxx> Cc: Martin K. Petersen <martin.petersen@xxxxxxxxxx> --- Bjorn, Subhash, I am not certain of some of these devfreq, and clk_scaling bits that are moved as part of this patch. Please help in reviewing the change in the light of these features, and related sequence should be followed. Thanks. drivers/scsi/ufs/ufshcd.c | 53 ++++++++++++++++++++++++++++++----------------- 1 file changed, 34 insertions(+), 19 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 397081d320b1..7273aec95a6c 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1749,6 +1749,34 @@ static ssize_t ufshcd_clkgate_enable_store(struct device *dev, return count; } +static void ufshcd_init_clk_scaling(struct ufs_hba *hba) +{ + char wq_name[sizeof("ufs_clkscaling_00")]; + + if (!ufshcd_is_clkscaling_supported(hba)) + return; + + INIT_WORK(&hba->clk_scaling.suspend_work, + ufshcd_clk_scaling_suspend_work); + INIT_WORK(&hba->clk_scaling.resume_work, + ufshcd_clk_scaling_resume_work); + + snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d", + hba->host->host_no); + hba->clk_scaling.workq = create_singlethread_workqueue(wq_name); + + ufshcd_clkscaling_init_sysfs(hba); +} + +static void ufshcd_exit_clk_scaling(struct ufs_hba *hba) +{ + if (!ufshcd_is_clkscaling_supported(hba)) + return; + + destroy_workqueue(hba->clk_scaling.workq); + ufshcd_devfreq_remove(hba); +} + static void ufshcd_init_clk_gating(struct ufs_hba *hba) { char wq_name[sizeof("ufs_clk_gating_00")]; @@ -6652,6 +6680,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba) */ if (ret && !ufshcd_eh_in_progress(hba) && !hba->pm_op_in_progress) { pm_runtime_put_sync(hba->dev); + ufshcd_exit_clk_scaling(hba); ufshcd_hba_exit(hba); } @@ -7187,12 +7216,9 @@ static void ufshcd_hba_exit(struct ufs_hba *hba) ufshcd_variant_hba_exit(hba); ufshcd_setup_vreg(hba, false); ufshcd_suspend_clkscaling(hba); - if (ufshcd_is_clkscaling_supported(hba)) { + if (ufshcd_is_clkscaling_supported(hba)) if (hba->devfreq) ufshcd_suspend_clkscaling(hba); - destroy_workqueue(hba->clk_scaling.workq); - ufshcd_devfreq_remove(hba); - } ufshcd_setup_clocks(hba, false); ufshcd_setup_hba_vreg(hba, false); hba->is_powered = false; @@ -7867,6 +7893,7 @@ void ufshcd_remove(struct ufs_hba *hba) ufshcd_disable_intr(hba, hba->intr_mask); ufshcd_hba_stop(hba, true); + ufshcd_exit_clk_scaling(hba); ufshcd_exit_clk_gating(hba); if (ufshcd_is_clkscaling_supported(hba)) device_remove_file(hba->dev, &hba->clk_scaling.enable_attr); @@ -8031,6 +8058,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) ufshcd_init_clk_gating(hba); + ufshcd_init_clk_scaling(hba); + /* * In order to avoid any spurious interrupt immediately after * registering UFS controller interrupt handler, clear any pending UFS @@ -8069,21 +8098,6 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) goto out_remove_scsi_host; } - if (ufshcd_is_clkscaling_supported(hba)) { - char wq_name[sizeof("ufs_clkscaling_00")]; - - INIT_WORK(&hba->clk_scaling.suspend_work, - ufshcd_clk_scaling_suspend_work); - INIT_WORK(&hba->clk_scaling.resume_work, - ufshcd_clk_scaling_resume_work); - - snprintf(wq_name, sizeof(wq_name), "ufs_clkscaling_%d", - host->host_no); - hba->clk_scaling.workq = create_singlethread_workqueue(wq_name); - - ufshcd_clkscaling_init_sysfs(hba); - } - /* * Set the default power management level for runtime and system PM. * Default power saving mode is to keep UFS link in Hibern8 state @@ -8121,6 +8135,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) out_remove_scsi_host: scsi_remove_host(hba->host); exit_gating: + ufshcd_exit_clk_scaling(hba); ufshcd_exit_clk_gating(hba); out_disable: hba->is_irq_enabled = false; -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html