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Vivek Gautam 38be2cbae3 media: venus: core: Set dma maximum segment size
[ Upstream commit de2563bce7 ]

Turning on CONFIG_DMA_API_DEBUG_SG results in the following error:

[  460.308650] ------------[ cut here ]------------
[  460.313490] qcom-venus aa00000.video-codec: DMA-API: mapping sg segment longer than device claims to support [len=4194304] [max=65536]
[  460.326017] WARNING: CPU: 3 PID: 3555 at src/kernel/dma/debug.c:1301 debug_dma_map_sg+0x174/0x254
[  460.338888] Modules linked in: venus_dec venus_enc videobuf2_dma_sg videobuf2_memops hci_uart btqca bluetooth venus_core v4l2_mem2mem videobuf2_v4l2 videobuf2_common ath10k_snoc ath10k_core ath lzo lzo_compress zramjoydev
[  460.375811] CPU: 3 PID: 3555 Comm: V4L2DecoderThre Tainted: G        W         4.19.1 #82
[  460.384223] Hardware name: Google Cheza (rev1) (DT)
[  460.389251] pstate: 60400009 (nZCv daif +PAN -UAO)
[  460.394191] pc : debug_dma_map_sg+0x174/0x254
[  460.398680] lr : debug_dma_map_sg+0x174/0x254
[  460.403162] sp : ffffff80200c37d0
[  460.406583] x29: ffffff80200c3830 x28: 0000000000010000
[  460.412056] x27: 00000000ffffffff x26: ffffffc0f785ea80
[  460.417532] x25: 0000000000000000 x24: ffffffc0f4ea1290
[  460.423001] x23: ffffffc09e700300 x22: ffffffc0f4ea1290
[  460.428470] x21: ffffff8009037000 x20: 0000000000000001
[  460.433936] x19: ffffff80091b0000 x18: 0000000000000000
[  460.439411] x17: 0000000000000000 x16: 000000000000f251
[  460.444885] x15: 0000000000000006 x14: 0720072007200720
[  460.450354] x13: ffffff800af536e0 x12: 0000000000000000
[  460.455822] x11: 0000000000000000 x10: 0000000000000000
[  460.461288] x9 : 537944d9c6c48d00 x8 : 537944d9c6c48d00
[  460.466758] x7 : 0000000000000000 x6 : ffffffc0f8d98f80
[  460.472230] x5 : 0000000000000000 x4 : 0000000000000000
[  460.477703] x3 : 000000000000008a x2 : ffffffc0fdb13948
[  460.483170] x1 : ffffffc0fdb0b0b0 x0 : 000000000000007a
[  460.488640] Call trace:
[  460.491165]  debug_dma_map_sg+0x174/0x254
[  460.495307]  vb2_dma_sg_alloc+0x260/0x2dc [videobuf2_dma_sg]
[  460.501150]  __vb2_queue_alloc+0x164/0x374 [videobuf2_common]
[  460.507076]  vb2_core_reqbufs+0xfc/0x23c [videobuf2_common]
[  460.512815]  vb2_reqbufs+0x44/0x5c [videobuf2_v4l2]
[  460.517853]  v4l2_m2m_reqbufs+0x44/0x78 [v4l2_mem2mem]
[  460.523144]  v4l2_m2m_ioctl_reqbufs+0x1c/0x28 [v4l2_mem2mem]
[  460.528976]  v4l_reqbufs+0x30/0x40
[  460.532480]  __video_do_ioctl+0x36c/0x454
[  460.536610]  video_usercopy+0x25c/0x51c
[  460.540572]  video_ioctl2+0x38/0x48
[  460.544176]  v4l2_ioctl+0x60/0x74
[  460.547602]  do_video_ioctl+0x948/0x3520
[  460.551648]  v4l2_compat_ioctl32+0x60/0x98
[  460.555872]  __arm64_compat_sys_ioctl+0x134/0x20c
[  460.560718]  el0_svc_common+0x9c/0xe4
[  460.564498]  el0_svc_compat_handler+0x2c/0x38
[  460.568982]  el0_svc_compat+0x8/0x18
[  460.572672] ---[ end trace ce209b87b2f3af88 ]---

>From above warning one would deduce that the sg segment will overflow
the device's capacity. In reality, the hardware can accommodate larger
sg segments.
So, initialize the max segment size properly to weed out this warning.

Based on a similar patch sent by Sean Paul for mdss:
https://patchwork.kernel.org/patch/10671457/

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Acked-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:38 +01:00
arch powerpc/xmon: Fix invocation inside lock region 2019-01-26 09:32:37 +01:00
block block: use rcu_work instead of call_rcu to avoid sleep in softirq 2019-01-22 21:40:35 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: ecc - regularize scalar for scalar multiplication 2019-01-26 09:32:35 +01:00
Documentation x86/speculation/l1tf: Drop the swap storage limit restriction when l1tf=off 2019-01-09 17:38:41 +01:00
drivers media: venus: core: Set dma maximum segment size 2019-01-26 09:32:38 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs pstore/ram: Do not treat empty buffers as valid 2019-01-26 09:32:37 +01:00
include bpf: Allow narrow loads with offset > 0 2019-01-26 09:32:34 +01:00
init kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 2019-01-22 21:40:34 +01:00
ipc ipc/shm.c: use ERR_CAST() for shm_lock() error return 2018-10-05 16:32:04 -07:00
kernel bpf: Allow narrow loads with offset > 0 2019-01-26 09:32:34 +01:00
lib fix int_sqrt64() for very large numbers 2019-01-22 21:40:34 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm: page_mapped: don't assume compound page is huge or THP 2019-01-16 22:04:36 +01:00
net netfilter: ipset: Allow matching on destination MAC address for mac and ipmac sets 2019-01-26 09:32:33 +01:00
samples samples: bpf: fix: error handling regarding kprobe_events 2019-01-26 09:32:35 +01:00
scripts x86, modpost: Replace last remnants of RETPOLINE with CONFIG_RETPOLINE 2019-01-16 22:04:29 +01:00
security selinux: always allow mounting submounts 2019-01-26 09:32:36 +01:00
sound ASoC: use dma_ops of parent device for acp_audio_dma 2019-01-26 09:32:38 +01:00
tools selftests/bpf: enable (uncomment) all tests in test_libbpf.sh 2019-01-26 09:32:34 +01:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt KVM: arm/arm64: Fix VMID alloc race by reverting to lock-less 2019-01-16 22:04:37 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Add Sasha as a stable branch maintainer 2018-12-01 09:37:25 +01:00
Makefile Linux 4.19.17 2019-01-22 21:40:38 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
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Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.