tree 71a4aa3204905180200bfb0c49cd290036d65c87
parent 676d23690fb62b5d51ba5d659935e9f7d9da9f8e
author Mugunthan V N <mugunthanvnm@ti.com> 1397120003 +0530
committer David S. Miller <davem@davemloft.net> 1397248061 -0400

drivers: net: cpsw: discard all packets received when interface is down

When the Ethernet interface is brought down during high Ethernet traffic,
then cpsw creates the following warn dump. When cpdma has already processed
the packet then the status will be greater than 0, so the cpsw_rx_handler
considers that the interface is up and try to resubmit one more rx buffer
to cpdma which fails as the DMA is in teardown process. This can be avoided
by checking the interface state and then process the received packet, if the
interface is down just discard and free the skb and return.

[ 2823.104591] WARNING: CPU: 0 PID: 1823 at drivers/net/ethernet/ti/cpsw.c:711 cpsw_rx_handler+0x148/0x164()
[ 2823.114654] Modules linked in:
[ 2823.117872] CPU: 0 PID: 1823 Comm: ifconfig Tainted: G        W     3.14.0-11992-gf34c4a3 #11
[ 2823.126860] [<c0014b5c>] (unwind_backtrace) from [<c00117e4>] (show_stack+0x10/0x14)
[ 2823.135030] [<c00117e4>] (show_stack) from [<c0533a9c>] (dump_stack+0x80/0x9c)
[ 2823.142619] [<c0533a9c>] (dump_stack) from [<c003f0e0>] (warn_slowpath_common+0x6c/0x90)
[ 2823.151141] [<c003f0e0>] (warn_slowpath_common) from [<c003f120>] (warn_slowpath_null+0x1c/0x24)
[ 2823.160336] [<c003f120>] (warn_slowpath_null) from [<c03caeb0>] (cpsw_rx_handler+0x148/0x164)
[ 2823.169314] [<c03caeb0>] (cpsw_rx_handler) from [<c03c730c>] (__cpdma_chan_free+0x90/0xa8)
[ 2823.178028] [<c03c730c>] (__cpdma_chan_free) from [<c03c7418>] (__cpdma_chan_process+0xf4/0x134)
[ 2823.187279] [<c03c7418>] (__cpdma_chan_process) from [<c03c7560>] (cpdma_chan_stop+0xb4/0x17c)
[ 2823.196349] [<c03c7560>] (cpdma_chan_stop) from [<c03c766c>] (cpdma_ctlr_stop+0x44/0x9c)
[ 2823.204872] [<c03c766c>] (cpdma_ctlr_stop) from [<c03cb708>] (cpsw_ndo_stop+0x154/0x188)
[ 2823.213321] [<c03cb708>] (cpsw_ndo_stop) from [<c046f0ec>] (__dev_close_many+0x84/0xc8)
[ 2823.221761] [<c046f0ec>] (__dev_close_many) from [<c046f158>] (__dev_close+0x28/0x3c)
[ 2823.230012] [<c046f158>] (__dev_close) from [<c0474ca8>] (__dev_change_flags+0x88/0x160)
[ 2823.238483] [<c0474ca8>] (__dev_change_flags) from [<c0474da0>] (dev_change_flags+0x18/0x48)
[ 2823.247316] [<c0474da0>] (dev_change_flags) from [<c04d12c4>] (devinet_ioctl+0x61c/0x6e0)
[ 2823.255884] [<c04d12c4>] (devinet_ioctl) from [<c045c660>] (sock_ioctl+0x68/0x2a4)
[ 2823.263789] [<c045c660>] (sock_ioctl) from [<c0125fe4>] (do_vfs_ioctl+0x78/0x61c)
[ 2823.271629] [<c0125fe4>] (do_vfs_ioctl) from [<c01265ec>] (SyS_ioctl+0x64/0x74)
[ 2823.279284] [<c01265ec>] (SyS_ioctl) from [<c000e580>] (ret_fast_syscall+0x0/0x48)

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>