This Linux kernel change "atl1: fix oops when changing tx/rx ring params" is included in the Linux 2.6.37 release. This change is authored by J. K. Cliburn <jcliburn [at] gmail.com> on Sat Jan 1 05:02:12 2011 +0000. The commit for this change in Linux stable tree is 2f32c86 (patch).
atl1: fix oops when changing tx/rx ring params Commit 3f5a2a713aad28480d86b0add00c68484b54febc zeroes out the statistics message block (SMB) and coalescing message block (CMB) when adapter ring resources are freed. This is desirable behavior, but, as a side effect, the commit leads to an oops when atl1_set_ringparam() attempts to alter the number of rx or tx elements in the ring buffer (by using ethtool -G, for example). We don't want SMB or CMB to change during this operation. Modify atl1_set_ringparam() to preserve SMB and CMB when changing ring parameters. Cc: [email protected] Signed-off-by: Jay Cliburn <[email protected]> Reported-by: Tõnu Raitviir <[email protected]> Signed-off-by: David S. Miller <[email protected]>
There are 10 lines of Linux source code added/deleted in this change. Code changes to Linux kernel are as follows.
drivers/net/atlx/atl1.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/net/atlx/atl1.c b/drivers/net/atlx/atl1.c index 5336310..3acf512 100644 --- a/drivers/net/atlx/atl1.c +++ b/drivers/net/atlx/atl1.c @@ -3504,6 +3504,8 @@ static int atl1_set_ringparam(struct net_device *netdev, struct atl1_rfd_ring rfd_old, rfd_new; struct atl1_rrd_ring rrd_old, rrd_new; struct atl1_ring_header rhdr_old, rhdr_new; + struct atl1_smb smb; + struct atl1_cmb cmb; int err; tpd_old = adapter->tpd_ring; @@ -3544,11 +3546,19 @@ static int atl1_set_ringparam(struct net_device *netdev, adapter->rrd_ring = rrd_old; adapter->tpd_ring = tpd_old; adapter->ring_header = rhdr_old; + /* + * Save SMB and CMB, since atl1_free_ring_resources + * will clear them. + */ + smb = adapter->smb; + cmb = adapter->cmb; atl1_free_ring_resources(adapter); adapter->rfd_ring = rfd_new; adapter->rrd_ring = rrd_new; adapter->tpd_ring = tpd_new; adapter->ring_header = rhdr_new; + adapter->smb = smb; + adapter->cmb = cmb; err = atl1_up(adapter); if (err)