2.6.25-rc4 de_stop_rxtx polling wrong

This untested patch _should_ fix:
	"(net de2104x) Kernel panic with de2104x tulip driver on boot"
	http://bugzilla.kernel.org/show_bug.cgi?id=3156

But the bug submitter isn't responding.  Same fix has been applied
to tulip.c (several years ago) and uli526x.c (Feb 2008) drivers.

[ The panic reported in the bug report was removed in a recently
  (march 2008) accepted patch from Ondrej Zary. ]

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/net/tulip/de2104x.c b/drivers/net/tulip/de2104x.c
index 567c62757e9d154ec39b5083d1f0f4b28bcf18ad..1b5edd646a8c924c835129280d9ad964186676f6 100644 (file)
--- a/drivers/net/tulip/de2104x.c
+++ b/drivers/net/tulip/de2104x.c
@@ -842,7 +842,7 @@ static inline int de_is_running (struct de_private *de)
 static void de_stop_rxtx (struct de_private *de)
 {
        u32 macmode;
-       unsigned int work = 1000;
+       unsigned int i = 1300/100;
 
        macmode = dr32(MacMode);
        if (macmode & RxTx) {
@@ -850,10 +850,14 @@ static void de_stop_rxtx (struct de_private *de)
                dr32(MacMode);
        }
 
-       while (--work > 0) {
+       /* wait until in-flight frame completes.
+        * Max time @ 10BT: 1500*8b/10Mbps == 1200us (+ 100us margin)
+        * Typically expect this loop to end in < 50 us on 100BT.
+        */
+       while (--i) {
                if (!de_is_running(de))
                        return;
-               cpu_relax();
+               udelay(100);
        }
 
        printk(KERN_WARNING "%s: timeout expired stopping DMA\n", de->dev->name);