[PATCH] scsi: ufs: core: Do not access null point in ufshpb_remove

From: Zhang Hui
Date: Wed Sep 20 2023 - 05:12:49 EST


From: zhanghui <zhanghui31@xxxxxxxxxx>

If hpb is not enabled or not allowed, some points will not be allocated in
init flow, so access them will trigger KE in ufshpb remove flow.

Call trace in rmmod ko:
destroy_workqueue+0x1c/0x234
ufshpb_remove+0x40/0x50
ufshcd_remove+0x3c/0xd0
...

Signed-off-by: zhanghui <zhanghui31@xxxxxxxxxx>
---
drivers/ufs/core/ufshpb.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/ufs/core/ufshpb.c b/drivers/ufs/core/ufshpb.c
index 255f8b38d0c2..fa345e161cb8 100644
--- a/drivers/ufs/core/ufshpb.c
+++ b/drivers/ufs/core/ufshpb.c
@@ -2656,6 +2656,9 @@ void ufshpb_init(struct ufs_hba *hba)

void ufshpb_remove(struct ufs_hba *hba)
{
+ if (!ufshpb_is_allowed(hba) || !hba->dev_info.hpb_enabled)
+ return;
+
mempool_destroy(ufshpb_page_pool);
mempool_destroy(ufshpb_mctx_pool);
kmem_cache_destroy(ufshpb_mctx_cache);
--
2.34.1