linux/drivers/net/ethernet/freescale
Duan Fugang-B38611 d842a31f12 net:fec: fix WARNING caused by lack of calls to dma_mapping_error()
The driver fails to check the results of DMA mapping and results in
the following warning: (with kernel config "CONFIG_DMA_API_DEBUG" enable)

------------[ cut here ]------------
WARNING: at lib/dma-debug.c:937 check_unmap+0x43c/0x7d8()
fec 2188000.ethernet: DMA-API: device driver failed to check map
error[device address=0x00000000383a8040] [size=2048 bytes] [mapped as single]

Modules linked in:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.10.17-16827-g9cdb0ba-dirty #188
[<80013c4c>] (unwind_backtrace+0x0/0xf8) from [<80011704>] (show_stack+0x10/0x14)
[<80011704>] (show_stack+0x10/0x14) from [<80025614>] (warn_slowpath_common+0x4c/0x6c)
[<80025614>] (warn_slowpath_common+0x4c/0x6c) from [<800256c8>] (warn_slowpath_fmt+0x30/0x40)
[<800256c8>] (warn_slowpath_fmt+0x30/0x40) from [<8026bfdc>] (check_unmap+0x43c/0x7d8)
[<8026bfdc>] (check_unmap+0x43c/0x7d8) from [<8026c584>] (debug_dma_unmap_page+0x6c/0x78)
[<8026c584>] (debug_dma_unmap_page+0x6c/0x78) from [<8038049c>] (fec_enet_rx_napi+0x254/0x8a8)
[<8038049c>] (fec_enet_rx_napi+0x254/0x8a8) from [<804dc8c0>] (net_rx_action+0x94/0x160)
[<804dc8c0>] (net_rx_action+0x94/0x160) from [<8002c758>] (__do_softirq+0xe8/0x1d0)
[<8002c758>] (__do_softirq+0xe8/0x1d0) from [<8002c8e8>] (do_softirq+0x4c/0x58)
[<8002c8e8>] (do_softirq+0x4c/0x58) from [<8002cb50>] (irq_exit+0x90/0xc8)
[<8002cb50>] (irq_exit+0x90/0xc8) from [<8000ea88>] (handle_IRQ+0x3c/0x94)
[<8000ea88>] (handle_IRQ+0x3c/0x94) from [<8000855c>] (gic_handle_irq+0x28/0x5c)
[<8000855c>] (gic_handle_irq+0x28/0x5c) from [<8000de00>] (__irq_svc+0x40/0x50)
Exception stack(0x815a5f38 to 0x815a5f80)
5f20:                                                       815a5f80 3b9aca00
5f40: 0fe52383 00000002 0dd8950e 00000002 81e7b080 00000000 00000000 815ac4d8
5f60: 806032ec 00000000 00000017 815a5f80 80059028 8041fc4c 60000013 ffffffff
[<8000de00>] (__irq_svc+0x40/0x50) from [<8041fc4c>] (cpuidle_enter_state+0x50/0xf0)
[<8041fc4c>] (cpuidle_enter_state+0x50/0xf0) from [<8041fd94>] (cpuidle_idle_call+0xa8/0x14c)
[<8041fd94>] (cpuidle_idle_call+0xa8/0x14c) from [<8000edac>] (arch_cpu_idle+0x10/0x4c)
[<8000edac>] (arch_cpu_idle+0x10/0x4c) from [<800582f8>] (cpu_startup_entry+0x60/0x130)
[<800582f8>] (cpu_startup_entry+0x60/0x130) from [<80bc7a48>] (start_kernel+0x2d0/0x328)
[<80bc7a48>] (start_kernel+0x2d0/0x328) from [<10008074>] (0x10008074)
---[ end trace c6edec32436e0042 ]---

Because dma-debug add new interfaces to debug dma mapping errors, pls refer
to: http://lwn.net/Articles/516640/

After dma mapping, it must call dma_mapping_error() to check mapping error,
otherwise the map_err_type alway is MAP_ERR_NOT_CHECKED, check_unmap() define
the mapping is not checked and dump the error msg. So,add dma_mapping_error()
checking to fix the WARNING

And RX DMA buffers are used repeatedly and the driver copies it into an skb,
fec_enet_rx() should not map or unmap, use dma_sync_single_for_cpu()/dma_sync_single_for_device()
instead of dma_map_single()/dma_unmap_single().

There have another potential issue:  fec_enet_rx() passes the DMA address to __va().
Physical and DMA addresses are *not* the same thing. They may differ if the device
is behind an IOMMU or bounce buffering was required, or just because there is a fixed
offset between the device and host physical addresses. Also fix it in this patch.

=============================================
V2: add net_ratelimit() to limit map err message.
    use dma_sync_single_for_cpu() instead of dma_map_single().
    fix the issue that pass DMA addresses to __va() to get virture address.
V1: initial send
=============================================

Signed-off-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14 16:37:33 -05:00
..
fs_enet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-11-13 17:40:34 +09:00
fec_main.c net:fec: fix WARNING caused by lack of calls to dma_mapping_error() 2013-11-14 16:37:33 -05:00
fec_mpc52xx_phy.c net: fec_mpc52xx_phy: remove unnecessary dev_set_drvdata() 2013-08-21 12:27:04 -07:00
fec_mpc52xx.c net: ethernet: use platform_{get,set}_drvdata() 2013-05-25 21:27:58 -07:00
fec_mpc52xx.h drivers/net: fix up stale paths from driver reorg 2012-01-30 12:54:40 -05:00
fec_ptp.c fec: Only pass pdev in fec_ptp_init() 2013-06-07 14:41:07 -07:00
fec.h net: fec: fix the error to get the previous BD entry 2013-09-04 14:14:54 -04:00
fsl_pq_mdio.c net: fsl_pq_mdio: remove unnecessary dev_set_drvdata() 2013-08-21 12:27:04 -07:00
gianfar_ethtool.c gianfar: Add flow control support 2013-08-13 15:28:53 -07:00
gianfar_ptp.c powerpc/83xx: gianfar_ptp: select 1588 clock source through dts file 2013-09-30 21:17:16 -07:00
gianfar_sysfs.c gianfar: Use netdev_<level> when possible 2013-04-14 15:41:49 -04:00
gianfar.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-11-13 17:40:34 +09:00
gianfar.h gianfar: Remove extern from function prototypes 2013-09-24 10:09:27 -04:00
Kconfig NET: FEC: dynamtic check DMA desc buff type 2013-01-04 15:15:39 -08:00
Makefile net: fec: build fec.c and fec_ptp.c to one module 2013-03-25 12:14:57 -04:00
ucc_geth_ethtool.c ucc_geth: Convert ugeth_<level> to pr_<level> 2013-04-14 15:41:49 -04:00
ucc_geth.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-11-13 17:40:34 +09:00
ucc_geth.h net: remove skb recycling 2012-10-07 00:40:54 -04:00
xgmac_mdio.c drivers: clean-up prom.h implicit includes 2013-10-09 20:04:04 -05:00