orinoco: reduce stack usage in firmware download path

orinoco_dl_firmware and symbol_dl_mage allocate large local
variables (1K); at least orinoco fails with panic or hung
kernel if 4K stacks is enabled.

Allocate large buffers dynamically at run time.

Tested-By: Andrey Borzenkov <arvidjaar@mail.ru> for Agere case

Signed-off-by: Andrey Borzenkov < arvidjaar@mail.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 29 insertions, 13 deletions

diff --git a/drivers/net/wireless/orinoco.c b/drivers/net/wireless/orinoco.c
index 50904771f291..e0512e49d6d3 100644
--- a/drivers/net/wireless/orinoco.c
+++ b/drivers/net/wireless/orinoco.c
@@ -433,7 +433,7 @@ struct fw_info {
 const static struct fw_info orinoco_fw[] = {
         { "", "agere_sta_fw.bin", "agere_ap_fw.bin", 0x00390000, 1000 },
         { "", "prism_sta_fw.bin", "prism_ap_fw.bin", 0, 1024 },
-        { "symbol_sp24t_prim_fw", "symbol_sp24t_sec_fw", "", 0x00003100, 0x100 }
+        { "symbol_sp24t_prim_fw", "symbol_sp24t_sec_fw", "", 0x00003100, 512 }
 };
 
 /* Structure used to access fields in FW
@@ -458,7 +458,7 @@ orinoco_dl_firmware(struct orinoco_private *priv,
                     int ap)
 {
         /* Plug Data Area (PDA) */
-        __le16 pda[512] = { 0 };
+        __le16 *pda;
 
         hermes_t *hw = &priv->hw;
         const struct firmware *fw_entry;
@@ -467,7 +467,11 @@ orinoco_dl_firmware(struct orinoco_private *priv,
         const unsigned char *end;
         const char *firmware;
         struct net_device *dev = priv->ndev;
-        int err;
+        int err = 0;
+
+        pda = kzalloc(fw->pda_size, GFP_KERNEL);
+        if (!pda)
+                return -ENOMEM;
 
         if (ap)
                 firmware = fw->ap_fw;
@@ -478,17 +482,17 @@ orinoco_dl_firmware(struct orinoco_private *priv,
                dev->name, firmware);
 
         /* Read current plug data */
-        err = hermes_read_pda(hw, pda, fw->pda_addr,
-                              min_t(u16, fw->pda_size, sizeof(pda)), 0);
+        err = hermes_read_pda(hw, pda, fw->pda_addr, fw->pda_size, 0);
         printk(KERN_DEBUG "%s: Read PDA returned %d\n", dev->name, err);
         if (err)
-                return err;
+                goto free;
 
         err = request_firmware(&fw_entry, firmware, priv->dev);
         if (err) {
                 printk(KERN_ERR "%s: Cannot find firmware %s\n",
                        dev->name, firmware);
-                return -ENOENT;
+                err = -ENOENT;
+                goto free;
         }
 
         hdr = (const struct orinoco_fw_header *) fw_entry->data;
@@ -532,6 +536,9 @@ orinoco_dl_firmware(struct orinoco_private *priv,
 
 abort:
         release_firmware(fw_entry);
+
+free:
+        kfree(pda);
         return err;
 }
 
@@ -549,12 +556,12 @@ symbol_dl_image(struct orinoco_private *priv, const struct fw_info *fw,
                 int secondary)
 {
         hermes_t *hw = &priv->hw;
-        int ret;
+        int ret = 0;
         const unsigned char *ptr;
         const unsigned char *first_block;
 
         /* Plug Data Area (PDA) */
-        __le16 pda[256];
+        __le16 *pda = NULL;
 
         /* Binary block begins after the 0x1A marker */
         ptr = image;
@@ -563,28 +570,33 @@ symbol_dl_image(struct orinoco_private *priv, const struct fw_info *fw,
 
         /* Read the PDA from EEPROM */
         if (secondary) {
-                ret = hermes_read_pda(hw, pda, fw->pda_addr, sizeof(pda), 1);
+                pda = kzalloc(fw->pda_size, GFP_KERNEL);
+                if (!pda)
+                        return -ENOMEM;
+
+                ret = hermes_read_pda(hw, pda, fw->pda_addr, fw->pda_size, 1);
                 if (ret)
-                        return ret;
+                        goto free;
         }
 
         /* Stop the firmware, so that it can be safely rewritten */
         if (priv->stop_fw) {
                 ret = priv->stop_fw(priv, 1);
                 if (ret)
-                        return ret;
+                        goto free;
         }
 
         /* Program the adapter with new firmware */
         ret = hermes_program(hw, first_block, end);
         if (ret)
-                return ret;
+                goto free;
 
         /* Write the PDA to the adapter */
         if (secondary) {
                 size_t len = hermes_blocks_length(first_block);
                 ptr = first_block + len;
                 ret = hermes_apply_pda(hw, ptr, pda);
+                kfree(pda);
                 if (ret)
                         return ret;
         }
@@ -608,6 +620,10 @@ symbol_dl_image(struct orinoco_private *priv, const struct fw_info *fw,
                 return -ENODEV;
 
         return 0;
+
+free:
+        kfree(pda);
+        return ret;
 }