RDMA/usnic: Avoid overly large buffers on stack
authorArnd Bergmann <arnd@arndb.de>
Fri, 6 Sep 2019 15:57:17 +0000 (17:57 +0200)
committerJason Gunthorpe <jgg@mellanox.com>
Fri, 13 Sep 2019 19:55:55 +0000 (16:55 -0300)
It's never a good idea to put a 1000-byte buffer on the kernel stack. The
compiler warns about this instance when usnic_ib_log_vf() gets inlined
into usnic_ib_pci_probe():

drivers/infiniband/hw/usnic/usnic_ib_main.c:543:12: error: stack frame size of 1044 bytes in function 'usnic_ib_pci_probe' [-Werror,-Wframe-larger-than=]

As this is only called for debugging purposes in the setup path, it's
trivial to convert to a dynamic allocation.

Link: https://lore.kernel.org/r/20190906155730.2750200-1-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
drivers/infiniband/hw/usnic/usnic_ib_main.c

index 03f54eb9404b0aa60c81677b7119b15c9aabc296..c9abe1c01e4eb4973e6647d7a77df9213e380536 100644 (file)
@@ -89,9 +89,15 @@ static void usnic_ib_dump_vf(struct usnic_ib_vf *vf, char *buf, int buf_sz)
 
 void usnic_ib_log_vf(struct usnic_ib_vf *vf)
 {
-       char buf[1000];
-       usnic_ib_dump_vf(vf, buf, sizeof(buf));
+       char *buf = kzalloc(1000, GFP_KERNEL);
+
+       if (!buf)
+               return;
+
+       usnic_ib_dump_vf(vf, buf, 1000);
        usnic_dbg("%s\n", buf);
+
+       kfree(buf);
 }
 
 /* Start of netdev section */