linux/drivers
Masaru Nagai 8ec3e8a192 ravb: do not use zero-length alignment DMA descriptor
Due to alignment requirements of the hardware transmissions are split into
two DMA descriptors, a small padding descriptor of 0 - 3 bytes in length
followed by a descriptor for rest of the packet.

In the case of IP packets the first descriptor will never be zero due to
the way that the stack aligns buffers for IP packets. However, for non-IP
packets it may be zero.

In that case it has been reported that timeouts occur, presumably because
transmission stops at the first zero-length DMA descriptor and thus the
packet is not transmitted. However, in my environment a BUG is triggered as
follows:

[   20.381417] ------------[ cut here ]------------
[   20.386054] kernel BUG at lib/swiotlb.c:495!
[   20.390324] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
[   20.395805] Modules linked in:
[   20.398862] CPU: 0 PID: 2089 Comm: mz Not tainted 4.10.0-rc3-00001-gf13ad2db193f #162
[   20.406689] Hardware name: Renesas Salvator-X board based on r8a7796 (DT)
[   20.413474] task: ffff80063b1f1900 task.stack: ffff80063a71c000
[   20.419404] PC is at swiotlb_tbl_map_single+0x178/0x2ec
[   20.424625] LR is at map_single+0x4c/0x98
[   20.428629] pc : [<ffff00000839c4c0>] lr : [<ffff00000839c680>] pstate: 800001c5
[   20.436019] sp : ffff80063a71f9b0
[   20.439327] x29: ffff80063a71f9b0 x28: ffff80063a20d500
[   20.444636] x27: ffff000008ed5000 x26: 0000000000000000
[   20.449944] x25: 000000067abe2adc x24: 0000000000000000
[   20.455252] x23: 0000000000200000 x22: 0000000000000001
[   20.460559] x21: 0000000000175ffe x20: ffff80063b2a0010
[   20.465866] x19: 0000000000000000 x18: 0000ffffcae6fb20
[   20.471173] x17: 0000ffffa09ba018 x16: ffff0000087c8b70
[   20.476480] x15: 0000ffffa084f588 x14: 0000ffffa09cfa14
[   20.481787] x13: 0000ffffcae87ff0 x12: 000000000063abe2
[   20.487098] x11: ffff000008096360 x10: ffff80063abe2adc
[   20.492407] x9 : 0000000000000000 x8 : 0000000000000000
[   20.497718] x7 : 0000000000000000 x6 : ffff000008ed50d0
[   20.503028] x5 : 0000000000000000 x4 : 0000000000000001
[   20.508338] x3 : 0000000000000000 x2 : 000000067abe2adc
[   20.513648] x1 : 00000000bafff000 x0 : 0000000000000000
[   20.518958]
[   20.520446] Process mz (pid: 2089, stack limit = 0xffff80063a71c000)
[   20.526798] Stack: (0xffff80063a71f9b0 to 0xffff80063a720000)
[   20.532543] f9a0:                                   ffff80063a71fa30 ffff00000839c680
[   20.540374] f9c0: ffff80063b2a0010 ffff80063b2a0010 0000000000000001 0000000000000000
[   20.548204] f9e0: 000000000000006e ffff80063b23c000 ffff80063b23c000 0000000000000000
[   20.556034] fa00: ffff80063b23c000 ffff80063a20d500 000000013b1f1900 0000000000000000
[   20.563864] fa20: ffff80063ffd18e0 ffff80063b2a0010 ffff80063a71fa60 ffff00000839cd10
[   20.571694] fa40: ffff80063b2a0010 0000000000000000 ffff80063ffd18e0 000000067abe2adc
[   20.579524] fa60: ffff80063a71fa90 ffff000008096380 ffff80063b2a0010 0000000000000000
[   20.587353] fa80: 0000000000000000 0000000000000001 ffff80063a71fac0 ffff00000864f770
[   20.595184] faa0: ffff80063b23caf0 0000000000000000 0000000000000000 0000000000000140
[   20.603014] fac0: ffff80063a71fb60 ffff0000087e6498 ffff80063a20d500 ffff80063b23c000
[   20.610843] fae0: 0000000000000000 ffff000008daeaf0 0000000000000000 ffff000008daeb00
[   20.618673] fb00: ffff80063a71fc0c ffff000008da7000 ffff80063b23c090 ffff80063a44f000
[   20.626503] fb20: 0000000000000000 ffff000008daeb00 ffff80063a71fc0c ffff000008da7000
[   20.634333] fb40: ffff80063b23c090 0000000000000000 ffff800600000037 ffff0000087e63d8
[   20.642163] fb60: ffff80063a71fbc0 ffff000008807510 ffff80063a692400 ffff80063a20d500
[   20.649993] fb80: ffff80063a44f000 ffff80063b23c000 ffff80063a69249c 0000000000000000
[   20.657823] fba0: 0000000000000000 ffff80063a087800 ffff80063b23c000 ffff80063a20d500
[   20.665653] fbc0: ffff80063a71fc10 ffff0000087e67dc ffff80063a20d500 ffff80063a692400
[   20.673483] fbe0: ffff80063b23c000 0000000000000000 ffff80063a44f000 ffff80063a69249c
[   20.681312] fc00: ffff80063a5f1a10 000000103a087800 ffff80063a71fc70 ffff0000087e6b24
[   20.689142] fc20: ffff80063a5f1a80 ffff80063a71fde8 000000000000000f 00000000000005ea
[   20.696972] fc40: ffff80063a5f1a10 0000000000000000 000000000000000f ffff00000887fbd0
[   20.704802] fc60: fffffff43a5f1a80 0000000000000000 ffff80063a71fc80 ffff000008880240
[   20.712632] fc80: ffff80063a71fd90 ffff0000087c7a34 ffff80063afc7180 0000000000000000
[   20.720462] fca0: 0000ffffcae6fe18 0000000000000014 0000000060000000 0000000000000015
[   20.728292] fcc0: 0000000000000123 00000000000000ce ffff0000088d2000 ffff80063b1f1900
[   20.736122] fce0: 0000000000008933 ffff000008e7cb80 ffff80063a71fd80 ffff0000087c50a4
[   20.743951] fd00: 0000000000008933 ffff000008e7cb80 ffff000008e7cb80 000000100000000e
[   20.751781] fd20: ffff80063a71fe4c 0000ffff00000300 0000000000000123 0000000000000000
[   20.759611] fd40: 0000000000000000 ffff80063b1f0000 000000000000000e 0000000000000300
[   20.767441] fd60: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[   20.775271] fd80: 0000000000000000 0000000000000000 ffff80063a71fda0 ffff0000087c8c20
[   20.783100] fda0: 0000000000000000 ffff000008082f30 0000000000000000 0000800637260000
[   20.790930] fdc0: ffffffffffffffff 0000ffffa0903078 0000000000000000 000000001ea87232
[   20.798760] fde0: 000000000000000f ffff80063a71fe40 ffff800600000014 ffff000000000001
[   20.806590] fe00: 0000000000000000 0000000000000000 ffff80063a71fde8 0000000000000000
[   20.814420] fe20: 0000000000000000 0000000000000000 0000000000000000 0000000000000001
[   20.822249] fe40: 0000000203000011 0000000000000000 0000000000000000 ffff80063a68aa00
[   20.830079] fe60: ffff80063a68aa00 0000000000000003 0000000000008933 ffff0000081f1b9c
[   20.837909] fe80: 0000000000000000 ffff000008082f30 0000000000000000 0000800637260000
[   20.845739] fea0: ffffffffffffffff 0000ffffa07ca81c 0000000060000000 0000000000000015
[   20.853569] fec0: 0000000000000003 000000001ea87232 000000000000000f 0000000000000000
[   20.861399] fee0: 0000ffffcae6fe18 0000000000000014 0000000000000300 0000000000000000
[   20.869228] ff00: 00000000000000ce 0000000000000000 00000000ffffffff 0000000000000000
[   20.877059] ff20: 0000000000000002 0000ffffcae87ff0 0000ffffa09cfa14 0000ffffa084f588
[   20.884888] ff40: 0000000000000000 0000ffffa09ba018 0000ffffcae6fb20 000000001ea87010
[   20.892718] ff60: 0000ffffa09b9000 0000ffffcae6fe30 0000ffffcae6fe18 000000000000000f
[   20.900548] ff80: 0000000000000003 000000001ea87232 0000000000000000 0000000000000000
[   20.908378] ffa0: 0000000000000000 0000ffffcae6fdc0 0000ffffa09a7824 0000ffffcae6fdc0
[   20.916208] ffc0: 0000ffffa0903078 0000000060000000 0000000000000003 00000000000000ce
[   20.924038] ffe0: 0000000000000000 0000000000000000 ffffffffffffffff ffffffffffffffff
[   20.931867] Call trace:
[   20.934312] Exception stack(0xffff80063a71f7e0 to 0xffff80063a71f910)
[   20.940750] f7e0: 0000000000000000 0001000000000000 ffff80063a71f9b0 ffff00000839c4c0
[   20.948580] f800: ffff80063a71f840 ffff00000888a6e4 ffff80063a24c418 ffff80063a24c448
[   20.956410] f820: 0000000000000000 ffff00000811cd54 ffff80063a71f860 ffff80063a24c458
[   20.964240] f840: ffff80063a71f870 ffff00000888b258 ffff80063a24c418 0000000000000001
[   20.972070] f860: ffff80063a71f910 ffff80063a7b7028 ffff80063a71f890 ffff0000088825e4
[   20.979899] f880: 0000000000000000 00000000bafff000 000000067abe2adc 0000000000000000
[   20.987729] f8a0: 0000000000000001 0000000000000000 ffff000008ed50d0 0000000000000000
[   20.995560] f8c0: 0000000000000000 0000000000000000 ffff80063abe2adc ffff000008096360
[   21.003390] f8e0: 000000000063abe2 0000ffffcae87ff0 0000ffffa09cfa14 0000ffffa084f588
[   21.011219] f900: ffff0000087c8b70 0000ffffa09ba018
[   21.016097] [<ffff00000839c4c0>] swiotlb_tbl_map_single+0x178/0x2ec
[   21.022362] [<ffff00000839c680>] map_single+0x4c/0x98
[   21.027411] [<ffff00000839cd10>] swiotlb_map_page+0xa4/0x138
[   21.033072] [<ffff000008096380>] __swiotlb_map_page+0x20/0x7c
[   21.038821] [<ffff00000864f770>] ravb_start_xmit+0x174/0x668
[   21.044484] [<ffff0000087e6498>] dev_hard_start_xmit+0x8c/0x120
[   21.050407] [<ffff000008807510>] sch_direct_xmit+0x108/0x1a0
[   21.056064] [<ffff0000087e67dc>] __dev_queue_xmit+0x194/0x4cc
[   21.061807] [<ffff0000087e6b24>] dev_queue_xmit+0x10/0x18
[   21.067214] [<ffff000008880240>] packet_sendmsg+0xf40/0x1220
[   21.072873] [<ffff0000087c7a34>] sock_sendmsg+0x18/0x2c
[   21.078097] [<ffff0000087c8c20>] SyS_sendto+0xb0/0xf0
[   21.083150] [<ffff000008082f30>] el0_svc_naked+0x24/0x28
[   21.088462] Code: d34bfef7 2a1803f3 1a9f86d6 35fff878 (d4210000)
[   21.094611] ---[ end trace 5bc544ad491f3814 ]---
[   21.099234] Kernel panic - not syncing: Fatal exception in interrupt
[   21.105587] Kernel Offset: disabled
[   21.109073] Memory Limit: none
[   21.112126] ---[ end Kernel panic - not syncing: Fatal exception in interrupt

Fixes: 2f45d1902a ("ravb: minimize TX data copying")
Signed-off-by: Masaru Nagai <masaru.nagai.vx@renesas.com
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-16 11:52:57 -05:00
..
accessibility
acpi Merge branches 'acpi-scan', 'acpi-sysfs', 'acpi-wdat' and 'acpi-tables' 2017-01-06 14:36:30 +01:00
amba
android
ata Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2016-12-13 15:30:50 -08:00
atm Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
auxdisplay
base PM / domains: Fix 'may be used uninitialized' build warning 2016-12-31 21:52:07 +01:00
bcma
block zram: support BDI_CAP_STABLE_WRITES 2017-01-10 18:31:55 -08:00
bluetooth Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-16 10:24:44 -08:00
bus cpu/hotplug: Cleanup state names 2016-12-25 10:47:44 +01:00
cdrom Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
char clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
clk One fix for a broken driver on Renesas RZ/A1 SoCs with bootloaders that don't 2017-01-06 15:35:27 -08:00
clocksource Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
connector
cpufreq Merge branch 'pm-cpufreq' 2017-01-06 14:34:52 +01:00
cpuidle Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2016-12-27 17:51:36 -08:00
dax libnvdimm for 4.10 2016-12-18 15:49:10 -08:00
dca
devfreq PM / devfreq: exynos-bus: Fix the wrong return value 2017-01-03 00:21:45 +01:00
dio Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
dma ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
dma-buf
edac Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
eisa
extcon sound updates for 4.10-rc1 2016-12-14 11:14:28 -08:00
firewire
firmware PSCI fixes for v4.10 2017-01-04 16:38:39 +01:00
fmc
fpga
gpio gpio: Move freeing of GPIO hogs before numbing of the device 2016-12-30 09:11:21 +01:00
gpu Merge branch 'drm-fixes-4.10' of git://people.freedesktop.org/~agd5f/linux into drm-fixes 2017-01-09 09:47:19 +10:00
hid HID: sensor-hub: Move the memset to sensor_hub_get_feature() 2017-01-02 14:01:30 +01:00
hsi
hv clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
hwmon hwmon: (lm90) fix temp1_max_alarm attribute 2017-01-02 10:15:28 -08:00
hwspinlock
hwtracing coresight/etm3/4x: Consolidate hotplug state space 2016-12-25 10:47:44 +01:00
i2c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
ide Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
idle Power management material for v4.10-rc1 2016-12-13 10:41:53 -08:00
iio First round of IIO fixes for the 4.10 cycle. 2017-01-02 16:59:44 +01:00
infiniband net/mlx4_core: Fix raw qp flow steering rules under SRIOV 2016-12-29 14:17:40 -05:00
input ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
iommu IOMMU Fixes for Linux v4.10-rc2 2017-01-06 10:49:36 -08:00
ipack
irqchip Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
isdn Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
leds cpu/hotplug: Cleanup state names 2016-12-25 10:47:44 +01:00
lguest Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
lightnvm Char/Misc driver patches for 4.10-rc1 2016-12-13 12:11:01 -08:00
macintosh Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mailbox ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
mcb
md Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
media ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
memory
memstick Merge branch 'for-4.10/block' of git://git.kernel.dk/linux-block 2016-12-13 10:19:16 -08:00
message Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mfd - New Device Support 2016-12-19 08:16:26 -08:00
misc mei: move write cb to completion on credentials failures 2017-01-04 18:22:44 +01:00
mmc Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
mtd Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
net ravb: do not use zero-length alignment DMA descriptor 2017-01-16 11:52:57 -05:00
nfc
ntb ntb_transport: Remove unnecessary call to ntb_peer_spad_read 2016-12-23 16:11:07 -05:00
nubus Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
nvdimm libnvdimm for 4.10 2016-12-18 15:49:10 -08:00
nvme Merge branch 'nvme-4.10' of git://git.infradead.org/nvme into for-linus 2016-12-22 11:54:46 -07:00
nvmem nvmem: fix nvmem_cell_read() return type doc 2017-01-04 18:22:47 +01:00
of pci-v4.10-changes 2016-12-15 12:46:48 -08:00
oprofile Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
parisc Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
parport Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
pci ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
pcmcia drivers/pcmcia/m32r_pcc.c: check return from add_pcc_socket 2016-12-12 18:55:06 -08:00
perf cpu/hotplug: Cleanup state names 2016-12-25 10:47:44 +01:00
phy SCSI misc on 20161213 2016-12-14 10:49:33 -08:00
pinctrl pinctrl: samsung: Fix the width of PINCFG_TYPE_DRV bitfields for Exynos5433 2016-12-30 14:27:42 +01:00
platform platform/x86: fujitsu-laptop: use brightness_set_blocking for LED-setting callbacks 2016-12-28 12:38:10 +02:00
pnp Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
power ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
powercap
pps
ps3
ptp Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-12 19:56:15 -08:00
pwm pwm: Changes for v4.10-rc1 2016-12-15 11:45:13 -08:00
rapidio
ras
regulator - New Device Support 2016-12-19 08:16:26 -08:00
remoteproc remoteproc: qcom_adsp_pil: select qcom_scm 2016-12-09 16:16:56 -08:00
reset ARM: SoC driver updates for v4.10 2016-12-15 16:03:25 -08:00
rpmsg rpmsg updates for v4.10 2016-12-13 08:52:45 -08:00
rtc ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
s390 ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
sbus Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
scsi Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-12-25 14:30:04 -08:00
sfi
sh lib: radix-tree: check accounting of existing slot replacement users 2016-12-12 18:55:08 -08:00
sn
soc powerpc updates for 4.10 2016-12-16 09:26:42 -08:00
spi dmaengine updates for 4.10-rc1 2016-12-14 20:42:45 -08:00
spmi
ssb
staging staging: octeon: Call SET_NETDEV_DEV() 2017-01-03 17:11:50 +01:00
target Merge branch 'scsi-target-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/bvanassche/linux 2016-12-21 10:16:05 -08:00
tc
thermal Power management material for v4.10-rc1 2016-12-13 10:41:53 -08:00
thunderbolt Char/Misc driver patches for 4.10-rc1 2016-12-13 12:11:01 -08:00
tty Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
uio uio-hv-generic: store physical addresses instead of virtual 2016-12-10 14:57:58 +01:00
usb USB: fix problems with duplicate endpoint addresses 2017-01-05 19:38:40 +01:00
uwb
vfio vfio-pci: Handle error from pci_iomap 2017-01-04 08:34:39 -07:00
vhost Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-16 10:24:44 -08:00
video video: fbdev: cobalt_lcdfb: Handle return NULL error from devm_ioremap 2017-01-04 12:58:45 +01:00
virt
virtio virtio_mmio: Set dev.release() to avoid warning 2016-12-16 00:13:39 +02:00
vlynq
vme
w1
watchdog Watchdog updates for v4.10 2016-12-24 11:27:45 -08:00
xen Merge branch 'stable/for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb 2017-01-06 10:53:21 -08:00
zorro Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
Kconfig
Makefile