From 0592c2178e3cce76e839365eed67e1481d618ff0 Mon Sep 17 00:00:00 2001 From: Vivek Gautam Date: Tue, 7 Aug 2018 23:17:39 +0530 Subject: [PATCH] scsi: ufshcd: Fix NULL pointer dereference for in ufshcd_init [ Upstream commit eebcc19646489b68399ce7b35d9c38eb9f4ec40f ] 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 Cc: Bjorn Andersson Cc: Subhash Jadavani Cc: Matthias Kaehlcke Cc: Evan Green Cc: Martin K. Petersen Reviewed-by: Evan Green Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- 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 4aaba3e..8bce755 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1772,6 +1772,34 @@ out: 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")]; @@ -6676,6 +6704,7 @@ out: */ 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); } @@ -7223,12 +7252,9 @@ 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; @@ -7908,6 +7934,7 @@ 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); @@ -8079,6 +8106,8 @@ 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 @@ -8117,21 +8146,6 @@ 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 @@ -8169,6 +8183,7 @@ 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; -- 2.7.4