[PATCH 4.19 053/131] cxgb4: fix adapter crash due to wrong MC size

[Greg Kroah-Hartman]

From: Vishal Kulkarni <vis...@chelsio.com>

[ Upstream commit ce222748078592afb51b810dc154531aeba4f512 ]

In the absence of MC1, the size calculation function
cudbg_mem_region_size() was returing wrong MC size and
resulted in adapter crash. This patch adds new argument
to cudbg_mem_region_size() which will have actual size
and returns error to caller in the absence of MC1.

Fixes: a1c69520f785 ("cxgb4: collect MC memory dump")
Signed-off-by: Vishal Kulkarni <vis...@chelsio.com>"
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c |   27 ++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cudbg_lib.c
@@ -1065,9 +1065,9 @@ static void cudbg_t4_fwcache(struct cudb
        }
 }
 
-static unsigned long cudbg_mem_region_size(struct cudbg_init *pdbg_init,
-                                          struct cudbg_error *cudbg_err,
-                                          u8 mem_type)
+static int cudbg_mem_region_size(struct cudbg_init *pdbg_init,
+                                struct cudbg_error *cudbg_err,
+                                u8 mem_type, unsigned long *region_size)
 {
        struct adapter *padap = pdbg_init->adap;
        struct cudbg_meminfo mem_info;
@@ -1076,15 +1076,23 @@ static unsigned long cudbg_mem_region_si
 
        memset(&mem_info, 0, sizeof(struct cudbg_meminfo));
        rc = cudbg_fill_meminfo(padap, &mem_info);
-       if (rc)
+       if (rc) {
+               cudbg_err->sys_err = rc;
                return rc;
+       }
 
        cudbg_t4_fwcache(pdbg_init, cudbg_err);
        rc = cudbg_meminfo_get_mem_index(padap, &mem_info, mem_type, &mc_idx);
-       if (rc)
+       if (rc) {
+               cudbg_err->sys_err = rc;
                return rc;
+       }
+
+       if (region_size)
+               *region_size = mem_info.avail[mc_idx].limit -
+                              mem_info.avail[mc_idx].base;
 
-       return mem_info.avail[mc_idx].limit - mem_info.avail[mc_idx].base;
+       return 0;
 }
 
 static int cudbg_collect_mem_region(struct cudbg_init *pdbg_init,
@@ -1092,7 +1100,12 @@ static int cudbg_collect_mem_region(stru
                                    struct cudbg_error *cudbg_err,
                                    u8 mem_type)
 {
-       unsigned long size = cudbg_mem_region_size(pdbg_init, cudbg_err, 
mem_type);
+       unsigned long size = 0;
+       int rc;
+
+       rc = cudbg_mem_region_size(pdbg_init, cudbg_err, mem_type, &size);
+       if (rc)
+               return rc;
 
        return cudbg_read_fw_mem(pdbg_init, dbg_buff, mem_type, size,
                                 cudbg_err);