NTB: Change WARN_ON_ONCE to pr_warn_once on unsafe

The unsafe doorbell and scratchpad access should display reason when
WARN is called.  Otherwise we get a stack dump without any explanation.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>

1 files changed, 16 insertions, 8 deletions

diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.c b/drivers/ntb/hw/intel/ntb_hw_intel.c
index 70924e5c0c72..ba4dc0d7e1f3 100644
--- a/drivers/ntb/hw/intel/ntb_hw_intel.c
+++ b/drivers/ntb/hw/intel/ntb_hw_intel.c
@@ -246,7 +246,8 @@ static inline int ndev_db_addr(struct intel_ntb_dev *ndev,
                                phys_addr_t *db_addr, resource_size_t *db_size,
                                phys_addr_t reg_addr, unsigned long reg)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_DB));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_DB))
+                pr_warn_once("%s: NTB unsafe doorbell access", __func__);
 
         if (db_addr) {
                 *db_addr = reg_addr + reg;
@@ -264,7 +265,8 @@ static inline int ndev_db_addr(struct intel_ntb_dev *ndev,
 static inline u64 ndev_db_read(struct intel_ntb_dev *ndev,
                                void __iomem *mmio)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_DB));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_DB))
+                pr_warn_once("%s: NTB unsafe doorbell access", __func__);
 
         return ndev->reg->db_ioread(mmio);
 }
@@ -272,7 +274,8 @@ static inline u64 ndev_db_read(struct intel_ntb_dev *ndev,
 static inline int ndev_db_write(struct intel_ntb_dev *ndev, u64 db_bits,
                                 void __iomem *mmio)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_DB));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_DB))
+                pr_warn_once("%s: NTB unsafe doorbell access", __func__);
 
         if (db_bits & ~ndev->db_valid_mask)
                 return -EINVAL;
@@ -287,7 +290,8 @@ static inline int ndev_db_set_mask(struct intel_ntb_dev *ndev, u64 db_bits,
 {
         unsigned long irqflags;
 
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_DB));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_DB))
+                pr_warn_once("%s: NTB unsafe doorbell access", __func__);
 
         if (db_bits & ~ndev->db_valid_mask)
                 return -EINVAL;
@@ -307,7 +311,8 @@ static inline int ndev_db_clear_mask(struct intel_ntb_dev *ndev, u64 db_bits,
 {
         unsigned long irqflags;
 
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_DB));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_DB))
+                pr_warn_once("%s: NTB unsafe doorbell access", __func__);
 
         if (db_bits & ~ndev->db_valid_mask)
                 return -EINVAL;
@@ -336,7 +341,8 @@ static inline int ndev_spad_addr(struct intel_ntb_dev *ndev, int idx,
                                  phys_addr_t *spad_addr, phys_addr_t reg_addr,
                                  unsigned long reg)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD))
+                pr_warn_once("%s: NTB unsafe scratchpad access", __func__);
 
         if (idx < 0 || idx >= ndev->spad_count)
                 return -EINVAL;
@@ -352,7 +358,8 @@ static inline int ndev_spad_addr(struct intel_ntb_dev *ndev, int idx,
 static inline u32 ndev_spad_read(struct intel_ntb_dev *ndev, int idx,
                                  void __iomem *mmio)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD))
+                pr_warn_once("%s: NTB unsafe scratchpad access", __func__);
 
         if (idx < 0 || idx >= ndev->spad_count)
                 return 0;
@@ -363,7 +370,8 @@ static inline u32 ndev_spad_read(struct intel_ntb_dev *ndev, int idx,
 static inline int ndev_spad_write(struct intel_ntb_dev *ndev, int idx, u32 val,
                                   void __iomem *mmio)
 {
-        WARN_ON_ONCE(ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD));
+        if (ndev_is_unsafe(ndev, NTB_UNSAFE_SPAD))
+                pr_warn_once("%s: NTB unsafe scratchpad access", __func__);
 
         if (idx < 0 || idx >= ndev->spad_count)
                 return -EINVAL;