(Forgot l-k when sending this off to [EMAIL PROTECTED] :/)

Hi.

The following patch tries to eliminate the interrupt flag bugs
identified by the stanford team a while back in drivers/net/wan/
comx-hw-mixcom.c. It moves request_region and request_irq outside
the cli()/restore_flags() pair as they can sleep and cleans up
some error paths wrt. resource deallocation. It applies against
244-ac18.

Comments would be nice as this is not my day job :)



--- linux-244-ac18-clean/drivers/net/wan/comx-hw-mixcom.c       Mon Dec 11 22:38:29 
2000
+++ linux-244-ac18/drivers/net/wan/comx-hw-mixcom.c     Sat May 26 22:45:44 2001
@@ -487,15 +487,18 @@
        struct mixcom_privdata *hw = ch->HW_privdata;
        struct proc_dir_entry *procfile = ch->procdir->subdir;
        unsigned long flags; 
+       int ret = -ENODEV;
 
-       if (!dev->base_addr || !dev->irq) return -ENODEV;
+       if (!dev->base_addr || !dev->irq)
+               goto err_ret;
 
 
        if(hw->channel==1) {
                if(!TWIN(dev) || !(COMX_CHANNEL(TWIN(dev))->init_status & 
                    IRQ_ALLOCATED)) {
                        printk(KERN_ERR "%s: channel 0 not yet 
initialized\n",dev->name);
-                       return -EAGAIN;
+                       ret = -EAGAIN;
+                       goto err_ret;
                }
        }
 
@@ -503,28 +506,29 @@
        /* Is our hw present at all ? Not checking for channel 0 if it is already 
           open */
        if(hw->channel!=0 || !(ch->init_status & IRQ_ALLOCATED)) {
-               if (check_region(dev->base_addr, MIXCOM_IO_EXTENT)) {
-                       return -EAGAIN;
+               if (!request_region(dev->base_addr, MIXCOM_IO_EXTENT, dev->name)) {
+                       ret = -EAGAIN;
+                       goto err_ret;
                }
                if (mixcom_probe(dev)) {
-                       return -ENODEV;
+                       ret = -ENODEV;
+                       goto err_release_region;
                }
        }
 
-       save_flags(flags); cli();
-
-       if(hw->channel==1) {
-               request_region(dev->base_addr, MIXCOM_IO_EXTENT, dev->name);
-       } 
-
        if(hw->channel==0 && !(ch->init_status & IRQ_ALLOCATED)) {
                if (request_irq(dev->irq, MIXCOM_interrupt, 0, 
                    dev->name, (void *)dev)) {
                        printk(KERN_ERR "MIXCOM: unable to obtain irq %d\n", dev->irq);
-                       return -EAGAIN;
+                       ret = -EAGAIN;
+                       goto err_restore_flags;
                }
+       }
+
+       save_flags(flags); cli();
+
+       if(hw->channel==0 && !(ch->init_status & IRQ_ALLOCATED)) {
                ch->init_status|=IRQ_ALLOCATED;
-               request_region(dev->base_addr, MIXCOM_IO_EXTENT, dev->name);
                mixcom_board_on(dev);
        }
 
@@ -560,6 +564,13 @@
        }
 
        return 0;
+       
+err_restore_flags:
+       restore_flags(flags);
+err_release_region:
+       release_region(dev->base_addr, MIXCOM_IO_EXTENT);
+err_ret:
+       return ret;
 }
 
 static int MIXCOM_close(struct net_device *dev)

-- 
        Rasmus([EMAIL PROTECTED])

"I'm not going to have some reporters pawing through our papers. We are
the president."  -Hillary Clinton commenting on the release of subpoenaed
documents.
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