Re: [PATCH] b44: netpoll locking fix
From: Francois Romieu <romieu@fr.zoreil.com>
Date: 2007-05-29 22:24:53
Stephen Hemminger [off-list ref] : â ...]
quoted hunk ↗ jump to hunk
Better to just get rid of using the lock as a transmit lock and use netif_tx_lock instead.--- a/drivers/net/b44.c 2007-05-29 09:51:43.000000000 -0700 +++ b/drivers/net/b44.c 2007-05-29 14:26:03.000000000 -0700@@ -607,6 +607,7 @@ static void b44_tx(struct b44 *bp) { u32 cur, cons; + netif_tx_lock(bp->dev); cur = br32(bp, B44_DMATX_STAT) & DMATX_STAT_CDMASK; cur /= sizeof(struct dma_desc);
(damn, you are quick)
I am not completely convinced.
1. netpoll_send_skb (calls netif_tx_trylock(dev))
-> netpoll_poll(np)
-> poll_napi(np)
-> np->dev->poll(np->dev, &budget) ( == b44_poll)
-> b44_tx
-> netif_tx_lock(bp->dev) *deadlock*
2. Hunk #5 clashes with John Linville's wireless-dev#master
3. Moderately appropriate for 2.6.22-rc (imho, fwiw, etc.)
--
Ueimor