On Thursday 21 April 2005 13:42, Martin Husemann wrote:
>  On Thu, Apr 21, 2005 at 07:52:13AM -0400, Christos Zoulas wrote:
>  > Is there any reason not to apply the supplied patch that makes the
>  > system stable?
>
>  No, but better completely understand what happens before doing so.
>
>  As wm_stop already tries to disable the receiver completely by doing
>  CSR_WRITE(sc, WMREG_RCTL, 0); - the question remains, why do the
>  interrupts happen.

My guess is the WMREG_ICR register contains a stale interrupt status for 
whatever reason, even after wm_stop() has been called, and this was the 
motivation behind my patch.

Two possible routes into wm_intr() spring to mind:

1) wm_stop() is always called at splnet(). If the card interrupts before 
wm_stop() completes its task, there's a fair chance wm_intr() will be 
called anyway when spl drops below IPL_NET, *even if* the card is no 
longer asserting its interrupt pin by that time (the interrupt will have 
already been recorded by the low-level dispatch code).

2) If the wm(4) card is sharing a PCI interrupt line with some other 
device then wm_intr() will be called regardless.

Cheers, Steve