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Date: Tue, 2 Nov 2004 17:56:40 +0000
From: Peter Edwards <peadar.edwards@gmail.com>
To: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
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Subject: Re: if_sk patch to get more info from people with problems
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Ok, I don't have this hardware, but dumb question:

A (very) quick look at the source reveals that buffers are allocated
via  sk_rxeof()->sk_newbuf()->sk_jalloc() in the interrupt receive
function, with the softc lock held in sk_rxeof().

They're freed by the mbuf system via a call to sk_jfree(), but that
doesn't hold the SK_LOCK. Is this possibly the source of the
corruption problems? What am I missing?
This compiles, anyway :-)

--- /tmp/if_sk.c        Tue Nov  2 17:49:26 2004
+++ if_sk.c     Tue Nov  2 17:52:20 2004
@@ -1115,12 +1115,14 @@
        if ((i < 0) || (i >= SK_JSLOTS))
                panic("sk_jfree: asked to free buffer that we don't manage!");
 
+       SK_LOCK(sc_if->sk_softc);
        entry = SLIST_FIRST(&sc_if->sk_jinuse_listhead);
        if (entry == NULL)
                panic("sk_jfree: buffer not in use!");
        entry->slot = i;
        SLIST_REMOVE_HEAD(&sc_if->sk_jinuse_listhead, jpool_entries);
        SLIST_INSERT_HEAD(&sc_if->sk_jfree_listhead, entry, jpool_entries);
+       SK_UNLOCK(sc_if->sk_softc);
 
        return;
 }