Re: Bugfix in arch/ppc/8260_io/fcc_enet.c linux-2.4.17
From: David Ashley <hidden>
Date: 2002-03-09 04:19:54
I don't know, I haven't tried that. I would think that when the netboot stuff takes effect it will bring the ethernet device in question "up". I have seen other ethernet drivers that actually deallocate the irq when they are down, and reallocate it when they are up. That's how I determined fcc_enet.c had a problem. Even when it is down you can watch the /proc/interrupts count up. So I knew the interrupt was getting called and inside the interrupt it was passing the packets onto the linux network stack. I think it is a safe bet this change won't hurt anything at all. I believe all functioning ethernet devices are supposed to have their IFF_UP bit set in the dev->flags field. I think a better fix would be to disable the interrupt, or even deallocate/reallocate the irq on down/up. I didn't trace out what happens when an interface is downed though, I don't know how the driver knows when its interface goes up or down. I tried strace ifconfig eth0 down To see what syscall was doing the magic, but I didn't find it. -Dave
David, Is there an impact of your change on the board doing a netboot and loading the rootfs from a nfs mount? Thanks Amit David Ashley wrote:quoted
I found a bug which was manifest when linux boots and lots of ethernet packets are coming in. I think the problem is because the fcc_enet.c
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