[PATCH 1/2] scsi: ufs: Fix a possible NULL pointer issue

[Can Guo]

During system resume/suspend, hba could be NULL. In this case, do not touch
eh_sem.

Fixes: 88a92d6ae4fe ("scsi: ufs: Serialize eh_work with system PM events and 
async scan")

Signed-off-by: Can Guo <c...@codeaurora.org>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index e221add..9829c8d 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -94,6 +94,8 @@
                       16, 4, buf, __len, false);                        \
 } while (0)
 
+static bool early_suspend;
+
 int ufshcd_dump_regs(struct ufs_hba *hba, size_t offset, size_t len,
                     const char *prefix)
 {
@@ -8896,8 +8898,14 @@ int ufshcd_system_suspend(struct ufs_hba *hba)
        int ret = 0;
        ktime_t start = ktime_get();
 
+       if (!hba) {
+               early_suspend = true;
+               return 0;
+       }
+
        down(&hba->eh_sem);
-       if (!hba || !hba->is_powered)
+
+       if (!hba->is_powered)
                return 0;
 
        if ((ufs_get_pm_lvl_to_dev_pwr_mode(hba->spm_lvl) ==
@@ -8945,9 +8953,12 @@ int ufshcd_system_resume(struct ufs_hba *hba)
        int ret = 0;
        ktime_t start = ktime_get();
 
-       if (!hba) {
-               up(&hba->eh_sem);
+       if (!hba)
                return -EINVAL;
+
+       if (unlikely(early_suspend)) {
+               early_suspend = false;
+               down(&hba->eh_sem);
        }
 
        if (!hba->is_powered || pm_runtime_suspended(hba->dev))
-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux 
Foundation Collaborative Project.