The goal is to be able to inherit the initial devconf parameters from the
current netns, ie the netns where this new netns has been created.
This is useful in a containers environment where /proc/sys is read only.
For example, if a pod is created with specifics devconf parameters and has
the capability to create netns, the user expects to get the same parameters
than his 'init_net', which is not the real init_net in this case.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are 4 IRQ documentation files under Documentation/*.txt.
Move them into a new directory (core-api/irq) and add a new
index file for it.
While here, use a title markup for the Debugging section of the
irq-domain.rst file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/2da7485c3718e1442e6b4c2dd66857b776e8899b.1588345503.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
There is an special chapter inside the core-api book about
some debug infrastructure like tracepoints and debug objects.
It sounded to me that this is the best place to add a chapter
explaining how to use a FireWire controller to do remote
kernel debugging, as explained on this document.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9b489d36d08ad89d3ad5aefef1f52a0715b29716.1588345503.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Make some miscellaneous fixes to the first paragraph of "ECC memory":
- Change the incorrect "74 bits" to "72 bits".
- Change "mentioned on" to "mentioned in".
- Remove the extra "extra".
- Rephrase some sentences as suggested by Matthew Wilcox.
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20200506162217.16633-1-longman@redhat.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
During recent patch discussion [1] it became apparent that the "other_node"
definition in the numastat documentation has always been different from actual
implementation. It was also noted that the stats can be innacurate on systems
with memoryless nodes.
This patch corrects the other_node definition (with minor tweaks to two more
definitions), adds a note about memoryless nodes and also two introductory
paragraphs to the numastat documentation.
[1] https://lore.kernel.org/linux-mm/20200504070304.127361-1-sandipan@linux.ibm.com/T/#u
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Sandipan Das <sandipan@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Link: https://lore.kernel.org/r/20200507120217.12313-1-vbabka@suse.cz
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This is a read-only export of NGROUPS_MAX, so this patch also changes
the declarations in kernel/sysctl.c to const.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200515160222.7994-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add callback for 'dmsetup message' to allow the reclaim process
to be triggered manually.
Eg.
dmsetup message /dev/dm-X 0 message
will start the reclaim process even if the default threshold
of 50 percent of free random zones is not reached.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Add callback to supply information for 'dmsetup status'
and 'dmsetup table'. The output for 'dmsetup status' is
0 <size> zoned <nr_zones> zones <nr_unmap_rnd>/<nr_rnd> random <nr_unmap_seq>/<nr_seq> sequential
where <nr_unmap_rnd> is the number of unmapped (ie free) random zones,
<nr_rnd> the total number of random zones, <nr_unmap_seq> the number
of unmapped sequential zones, and <nr_seq> the total number of
sequential zones.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This new target is similar to the linear target except that it emulates
a smaller logical block size on a device with a larger logical block
size. Its main purpose is to emulate 512 byte sectors on 4K native
disks (i.e. 512e).
See Documentation/admin-guide/device-mapper/dm-ebs.rst for details.
Reviewed-by: Damien Le Moal <DamienLeMoal@wdc.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [Kconfig fixes]
Signed-off-by: Zheng Bin <zhengbin13@huawei.com> [static fixes]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The user is not supposed to thinker with the underlying sysrq_key_op.
Make that explicit by adding a handful of const notations.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
Link: https://lore.kernel.org/r/20200513214351.2138580-2-emil.l.velikov@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Sometimes it is useful to preserve batches of configs when making
localmodconfig. For example, I usually don't want any usb and fs
modules to be disabled. Now we can do it by:
$ make LMC_KEEP="drivers/usb:fs" localmodconfig
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Add documentation for KERNELPACMASK variable being added to the vmcoreinfo.
It indicates the PAC bits mask information of signed kernel pointers if
Armv8.3-A Pointer Authentication feature is present.
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/1589202116-18265-2-git-send-email-amit.kachhap@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
fixes.2020.04.27a: Miscellaneous fixes.
kfree_rcu.2020.04.27a: Changes related to kfree_rcu().
rcu-tasks.2020.04.27a: Addition of new RCU-tasks flavors.
stall.2020.04.27a: RCU CPU stall-warning updates.
torture.2020.05.07a: Torture-test updates.
This commit provides an rcutorture.stall_gp_kthread module parameter
to allow rcutorture to starve the grace-period kthread. This allows
testing the code that detects such starvation.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit aids testing of RCU task stall warning messages by adding
an rcutorture.stall_cpu_block module parameter that results in the
induced stall sleeping within the RCU read-side critical section.
Spinning with interrupts disabled is still available via the
rcutorture.stall_cpu_irqsoff module parameter, and specifying neither
of these two module parameters will spin with preemption disabled.
Note that sleeping (as opposed to preemption) results in additional
complaints from RCU at context-switch time, so yet more testing.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Sphinx 2.4.4 produces this warning:
Documentation/admin-guide/media/ipu3.rst:235: WARNING: Title underline too short.
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Based on the firmware fallback mechanisms documentation and the
implementation in drivers/base/firmware_loader/fallback.c.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200429205757.8677-2-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Based on the ftrace documentation, the tp_printk boot parameter
documentation, and the implementation in kernel/trace/trace.c.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20200429205757.8677-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
After adding all cardlists, this file became too big. Split
it on smaller files, in order to make easier to maintain.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
On several parts of the document, it mentions "PCI ID", when
it is actually referring to the subsystem's part of the PCI
ID.
Change the language to let it be clear.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add some explanation of the ImgU running mode and add more information
about firmware selection and running mode usage.
Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
5.7 merge window.
- Fix potential for DM writecache data corruption during DM table
reloads.
- Fix DM verity's FEC support's hash block number calculation in
verity_fec_decode().
- Fix bio-based DM multipath crash due to use of stale copy of
MPATHF_QUEUE_IO flag state in __map_bio().
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Merge tag 'for-5.7/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- Document DM integrity allow_discard feature that was added during 5.7
merge window.
- Fix potential for DM writecache data corruption during DM table
reloads.
- Fix DM verity's FEC support's hash block number calculation in
verity_fec_decode().
- Fix bio-based DM multipath crash due to use of stale copy of
MPATHF_QUEUE_IO flag state in __map_bio().
* tag 'for-5.7/dm-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm multipath: use updated MPATHF_QUEUE_IO on mapping for bio-based mpath
dm verity fec: fix hash block number in verity_fec_decode
dm writecache: fix data corruption when reloading the target
dm integrity: document allow_discard option
- add SPDX header;
- add a document title;
- mark code blocks and literals as such;
- mark tables as such;
- add notes markups;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- add SPDX header;
- add a document title;
- mark lists as such;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Not much to be done here:
- add SPDX header;
- add a document title;
- mark a literal as such, in order to avoid a warning;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- add SPDX header;
- adjust titles and chapters, adding proper markups;
- mark code blocks and literals as such;
- mark lists as such;
- mark tables as such;
- use footnote markup;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- add SPDX header;
- adjust titles and chapters, adding proper markups;
- mark lists as such;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on the implementation in kernel/sysctl.c (the proc_do_cad_pid()
function), kernel/reboot.c, and include/linux/sched/signal.h.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200423183651.15365-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit provides a rcupdate.rcu_task_ipi_delay kernel boot parameter
that specifies how old the RCU tasks trace grace period must be before
the grace-period kthread starts sending IPIs. This delay allows more
tasks to pass through rcu_tasks_qs() quiescent states, thus reducing
(or even eliminating) the number of IPIs that must be sent.
On a short rcutorture test setting this kernel boot parameter to HZ/2
resulted in zero IPIs for all 877 RCU-tasks trace grace periods that
elapsed during that test.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add the initrdmem option:
initrdmem=ss[KMG],nn[KMG]
which is used to specify the physical address of the initrd, almost
always an address in FLASH. Also add code for x86 to use the existing
phys_init_start and phys_init_size variables in the kernel.
This is useful in cases where a kernel and an initrd is placed in FLASH,
but there is no firmware file system structure in the FLASH.
One such situation occurs when unused FLASH space on UEFI systems has
been reclaimed by, e.g., taking it from the Management Engine. For
example, on many systems, the ME is given half the FLASH part; not only
is 2.75M of an 8M part unused; but 10.75M of a 16M part is unused. This
space can be used to contain an initrd, but need to tell Linux where it
is.
This space is "raw": due to, e.g., UEFI limitations: it can not be added
to UEFI firmware volumes without rebuilding UEFI from source or writing
a UEFI device driver. It can be referenced only as a physical address
and size.
At the same time, if a kernel can be "netbooted" or loaded from GRUB or
syslinux, the option of not using the physical address specification
should be available.
Then, it is easy to boot the kernel and provide an initrd; or boot the
the kernel and let it use the initrd in FLASH. In practice, this has
proven to be very helpful when integrating Linux into FLASH on x86.
Hence, the most flexible and convenient path is to enable the initrdmem
command line option in a way that it is the last choice tried.
For example, on the DigitalLoggers Atomic Pi, an image into FLASH can be
burnt in with a built-in command line which includes:
initrdmem=0xff968000,0x200000
which specifies a location and size.
[ bp: Massage commit message, make it passive. ]
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Link: http://lkml.kernel.org/r/CAP6exYLK11rhreX=6QPyDQmW7wPHsKNEFtXE47pjx41xS6O7-A@mail.gmail.com
Link: https://lkml.kernel.org/r/20200426011021.1cskg0AGd%akpm@linux-foundation.org
Here are a number of USB driver fixes for 5.7-rc3.
Nothing huge, just the usual collection of:
- xhci fixes
- gadget driver fixes
- syzkaller fuzzing fixes
- new device ids and DT bindings
- new quirks added for broken devices
A few of the gadget driver fixes show up twice here as they were applied
to my branch, and also by Felipe to his branch which I then pulled in as
we got out of sync a bit.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg KH:
"Here are a number of USB driver fixes for 5.7-rc3.
Nothing huge, just the usual collection of:
- xhci fixes
- gadget driver fixes
- syzkaller fuzzing fixes
- new device ids and DT bindings
- new quirks added for broken devices
A few of the gadget driver fixes show up twice here as they were
applied to my branch, and also by Felipe to his branch which I then
pulled in as we got out of sync a bit.
All of these have been in linux-next with no reported issues"
* tag 'usb-5.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (33 commits)
USB: sisusbvga: Change port variable from signed to unsigned
usb-storage: Add unusual_devs entry for JMicron JMS566
USB: hub: Revert commit bd0e6c9614 ("usb: hub: try old enumeration scheme first for high speed devices")
USB: hub: Fix handling of connect changes during sleep
usb: typec: altmode: Fix typec_altmode_get_partner sometimes returning an invalid pointer
xhci: Don't clear hub TT buffer on ep0 protocol stall
xhci: prevent bus suspend if a roothub port detected a over-current condition
xhci: Fix handling halted endpoint even if endpoint ring appears empty
usb: raw-gadget: Fix copy_to/from_user() checks
usb: raw-gadget: fix raw_event_queue_fetch locking
usb: gadget: udc: atmel: Fix vbus disconnect handling
usb: dwc3: gadget: Fix request completion check
USB: Add USB_QUIRK_DELAY_CTRL_MSG and USB_QUIRK_DELAY_INIT for Corsair K70 RGB RAPIDFIRE
phy: tegra: Select USB_COMMON for usb_get_maximum_speed()
usb: typec: tcpm: Ignore CC and vbus changes in PORT_RESET change
usb: f_fs: Clear OS Extended descriptor counts to zero in ffs_data_reset()
cdc-acm: introduce a cool down
cdc-acm: close race betrween suspend() and acm_softint
UAS: fix deadlock in error handling and PM flushing work
UAS: no use logging any details in case of ENODEV
...
Commit bd0e6c9614 ("usb: hub: try old enumeration scheme first for
high speed devices") changed the way the hub driver enumerates
high-speed devices. Instead of using the "new" enumeration scheme
first and switching to the "old" scheme if that doesn't work, we start
with the "old" scheme. In theory this is better because the "old"
scheme is slightly faster -- it involves resetting the device only
once instead of twice.
However, for a long time Windows used only the "new" scheme. Zeng Tao
said that Windows 8 and later use the "old" scheme for high-speed
devices, but apparently there are some devices that don't like it.
William Bader reports that the Ricoh webcam built into his Sony Vaio
laptop not only doesn't enumerate under the "old" scheme, it gets hung
up so badly that it won't then enumerate under the "new" scheme! Only
a cold reset will fix it.
Therefore we will revert the commit and go back to trying the "new"
scheme first for high-speed devices.
Reported-and-tested-by: William Bader <williambader@hotmail.com>
Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: bd0e6c9614 ("usb: hub: try old enumeration scheme first for high speed devices")
CC: Zeng Tao <prime.zeng@hisilicon.com>
CC: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel + tools/perf:
Alexey Budankov:
- Introduce CAP_PERFMON to kernel and user space.
callchains:
Adrian Hunter:
- Allow using Intel PT to synthesize callchains for regular events.
Kan Liang:
- Stitch LBR records from multiple samples to get deeper backtraces,
there are caveats, see the csets for details.
perf script:
Andreas Gerstmayr:
- Add flamegraph.py script
BPF:
Jiri Olsa:
- Synthesize bpf_trampoline/dispatcher ksymbol events.
perf stat:
Arnaldo Carvalho de Melo:
- Honour --timeout for forked workloads.
Stephane Eranian:
- Force error in fallback on :k events, to avoid counting nothing when
the user asks for kernel events but is not allowed to.
perf bench:
Ian Rogers:
- Add event synthesis benchmark.
tools api fs:
Stephane Eranian:
- Make xxx__mountpoint() more scalable
libtraceevent:
He Zhe:
- Handle return value of asprintf.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-5.8-20200420' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:
kernel + tools/perf:
Alexey Budankov:
- Introduce CAP_PERFMON to kernel and user space.
callchains:
Adrian Hunter:
- Allow using Intel PT to synthesize callchains for regular events.
Kan Liang:
- Stitch LBR records from multiple samples to get deeper backtraces,
there are caveats, see the csets for details.
perf script:
Andreas Gerstmayr:
- Add flamegraph.py script
BPF:
Jiri Olsa:
- Synthesize bpf_trampoline/dispatcher ksymbol events.
perf stat:
Arnaldo Carvalho de Melo:
- Honour --timeout for forked workloads.
Stephane Eranian:
- Force error in fallback on :k events, to avoid counting nothing when
the user asks for kernel events but is not allowed to.
perf bench:
Ian Rogers:
- Add event synthesis benchmark.
tools api fs:
Stephane Eranian:
- Make xxx__mountpoint() more scalable
libtraceevent:
He Zhe:
- Handle return value of asprintf.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In order to better organize the main admin-guide index,
place the driver-specific indexes on separate files.
This ensures a more consistent numbering at the main index.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Separate the generic documentation from the driver-specific
parts, and use a better title for the documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The old cards.rst file doesn't exist anymore. Also, it is not
the right reference there, as it should be pointing to the
bttv-specific cardlist.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
While test drivers is probably something that normal users
won't bother, it doesn't hurt to add them to the card list.
This way, all drivers, except for the ones under staging,
would be listed there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The SPI cards are also under the concept of "platform" drivers
as defined at the section introduction.
So, add a SPI card list there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Having a table with a list of all USB drivers seems worth,
and it comes almost for free, as we can just use Kconfig
descriptions (with some adjustments).
So, add a table for that.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Instead of listing "other" PCI card list, just add a list with
the existing drivers (not including sub-drivers).
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The frontend drivers list is incomplete. Update it from
what's there at the Kernel Kconfig files.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The DVB cards.rst file is old and outdated. It also contains
data that are contained on other cardlists. Remove the
duplicated information and split frontends and PCI cards on
separate files.
As all USB cards already have their own card lists, just drop
the old USB data there.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There are several other USB cards. Most of them support just
one device. The only exception is the "pwc" driver. But, as
updates to it are not frequent, let's just place everything
manually into a single file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The siano driver looks like em28xx, except that its cards
are split on 3 drivers.
Add a card list for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The cardlist section is important for some boards, because they
may require extra modprobe parameters.
Improve the docs to mention that.
Thanks-to: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for providing me some PCI IDs
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Several of the existing documents under the media admin-guide
contain build procedures.
Add an specific chapter describing it. This document was
partially inspired on the modifications I made to the bttv.rst
file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The media's admin guide is currently just a group of
not-connected docs.
Add an introduction chapter for it to start making sense
to a random reader.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
It is interesting to have a card list also for cx231xx
driver, as it currently supports 27 different boards.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Improve the documentation by providing examples on how to test camera
capture on imx6q-sabresd via v4l2-ctl and Gstreamer.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam<slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
In order to improve the documentation, provide the OV5640 MIPI module
part number that is used on the imx6q-sabresd board.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The current example for imx6q-sabresd is for a direct conversion pipeline.
Provide an extra example using unprocessed video capture for completeness.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam <slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The current instructions for imx6q-sabresd do not lead to functional
capture on OV5640 MIPI CSI-2.
The reason for this, as explained by Steve Longerbeam, is that OV5640 by
default transmits on virtual channel 0, not channel 1 as is given in the
instructions.
Adapt the instructions to use virtual channel 0 so that a working
camera setup can be achieved on imx6q-sabresd.
Also, since we are using an IC direct conversion pipeline, improve
the example by demonstrating colorspace and scaling.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Steve Longerbeam<slongerbeam@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Changes to make the text more formal and organized. The reasons are now cited and described at the same time.
Minor grammatical problems have also been fixed.
Signed-off-by: Cristian Souza <cristianmsbr@gmail.com>
Link: https://lore.kernel.org/r/20200411010201.GA22706@darkstar
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Based on the implementation in kernel/bpf/syscall.c,
kernel/bpf/trampoline.c, include/linux/filter.h, and the documentation
in bpftool-prog.rst.
Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200315122648.20558-1-steve@sk2.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Several parts of this document define literals: ioctl names,
function calls, directory patches, etc. Mark those as literal
blocks, in order to improve its readability (both at text mode
and after parsed by Sphinx.
This fixes those two warnings:
Documentation/admin-guide/mm/userfaultfd.rst:139: WARNING: Inline emphasis start-string without end-string.
Documentation/admin-guide/mm/userfaultfd.rst:139: WARNING: Inline emphasis start-string without end-string.
produced during documentation build.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/2ae061761baf8fe00cdf8a7e6dae293756849a05.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Sphinx produce some warnings due to a bad table format:
Documentation/admin-guide/ras.rst:358: WARNING: Definition list ends without a blank line; unexpected unindent.
Documentation/admin-guide/ras.rst:358: WARNING: Definition list ends without a blank line; unexpected unindent.
Documentation/admin-guide/ras.rst:363: WARNING: Definition list ends without a blank line; unexpected unindent.
Documentation/admin-guide/ras.rst:363: WARNING: Definition list ends without a blank line; unexpected unindent.
Rearrange the things there in order to supress the warnings
while being precise at the Sphinx output about how ranks are
mapped into csrows.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/9e1bb44d6dbedb5b6f049d081b47da1f9620de16.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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Merge tag 'v5.7-rc2' into patchwork
Linux 5.7-rc2
* tag 'v5.7-rc2': (331 commits)
Linux 5.7-rc2
mm: Fix MREMAP_DONTUNMAP accounting on VMA merge
xattr.h: Replace zero-length array with flexible-array member
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
tpm_eventlog.h: Replace zero-length array with flexible-array member
ti_wilink_st.h: Replace zero-length array with flexible-array member
swap.h: Replace zero-length array with flexible-array member
skbuff.h: Replace zero-length array with flexible-array member
sched: topology.h: Replace zero-length array with flexible-array member
rslib.h: Replace zero-length array with flexible-array member
rio.h: Replace zero-length array with flexible-array member
posix_acl.h: Replace zero-length array with flexible-array member
platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
memcontrol.h: Replace zero-length array with flexible-array member
list_lru.h: Replace zero-length array with flexible-array member
lib: cpu_rmap: Replace zero-length array with flexible-array member
irq.h: Replace zero-length array with flexible-array member
ihex.h: Replace zero-length array with flexible-array member
igmp.h: Replace zero-length array with flexible-array member
...
After recent changes allowing scale-invariant utilization to be
used on x86, the schedutil governor on top of intel_pstate in the
passive mode should be on par with (or better than) the active mode
"powersave" algorithm of intel_pstate on systems in which
hardware-managed P-states (HWP) are not used, so it should not be
necessary to use the internal scaling algorithm in those cases.
Accordingly, modify intel_pstate to start in the passive mode by
default if the processor at hand does not support HWP of if the driver
is requested to avoid using HWP through the kernel command line.
Among other things, that will allow utilization clamps and the
support for RT/DL tasks in the schedutil governor to be utilized on
systems in which intel_pstate is used.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Update the kernel.rst documentation file with the information related to
usage of CAP_PERFMON capability to secure performance monitoring and
observability operations in system.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/84c32383-14a2-fa35-16b6-f9e59bd37240@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Update perf-security.rst documentation file with the information
related to usage of CAP_PERFMON capability to secure performance
monitoring and observability operations in system.
Committer notes:
While testing 'perf top' under cap_perfmon I noticed that it needs
some more capability and Alexey pointed out cap_ipc_lock, as needed by
this kernel chunk:
kernel/events/core.c: 6101
if ((locked > lock_limit) && perf_is_paranoid() &&
!capable(CAP_IPC_LOCK)) {
ret = -EPERM;
goto unlock;
}
So I added it to the documentation, and also mentioned that if the
libcap version doesn't yet supports 'cap_perfmon', its numeric value can
be used instead, i.e. if:
# setcap "cap_perfmon,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf
Fails, try:
# setcap "38,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf
I also added a paragraph stating that using an unpatched libcap will
fail the check for CAP_PERFMON, as it checks the cap number against a
maximum to see if it is valid, which makes it use as the default the
'cycles:u' event, even tho a cap_perfmon capable perf binary can get
kernel samples, to workaround that just use, e.g.:
# perf top -e cycles
# perf record -e cycles
And it will sample kernel and user modes.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/17278551-9399-9ebe-d665-8827016a217d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Documentation for the kernel.modprobe sysctl was added both by
commit 0317c5371e ("docs: merge debugging-modules.txt into
sysctl/kernel.rst") and by commit 6e71582506 ("docs: admin-guide:
document the kernel.modprobe sysctl"), resulting in the same sysctl
being documented in two places. Merge these into one place.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200414172430.230293-1-ebiggers@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
In order to make easier for people to navigate between the
three media guides, add cross-references between them
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The copyright info is not the most valuable information
there. Move them to the end.
While here, change the copyright to cover up to this
year (2020).
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This file is very old, and doesn't match the current udev
behavior.
I wanted to preserve it, because we'll need some udev
description some day about how to keep names unique,
but there's nothing here to help with that...
So, be it: let's just discard this document, as it doesn't
provide anything useful anymore.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There aren't much to be done here... almost everything is
still valid. The supported boards even reflect the current
driver's state. Yet, some things changed, so let's keep
this document updated.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There are several things here that are outdated, because this
document was written a long time ago.
Update them to reflect the current status of the driver and
the media subsystem.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This file contains lots of obsoleted information. Update it
to reflect the current status and tools used by Digital TV
users and add pointers to the current locations and to
LinuxTV wiki pages.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Do some cleanups at the document in order to mark two
literal blocks as such.
While here, simplify two block markups, using the less
verbose option (::).
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There aren't many boards supported by this driver. So, add
a list for it manually generated.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This document is... old. The bttv driver was one of the first
drivers at the Kernel. So, the document became a little obsoleted.
Update it to reflect some changes that happened along the time
affecting this driver and the subsystem.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This document is very outdated, and doesn't match the
upstream current way.
Update it, making some parts a little bit more generic.
While the main focus of this document is digital TV
cards, its content also may also help someone with just
analog TV support.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
While this is old, now that we moved the intro part of it,
its contents seem to be valid, if we mention that we're
talking only about the BT878 support.
Update the document title accordingly and remove the obsolete
note from it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This document doesn't describe the DVB subsystem. Instead, it
just contain references to some places.
Better name it and improve its contents.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
The content there is somewhat outdated. Update to reflect
the current status.
While here, remove extra spaces, as we won't be preserving
left margin alinment on this document.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Part of this document has nothing to do with the Avermedia
driver. It is generic to the entire subsystem. So, split it
on a separate file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
There were some changes at the drivers adding support for
more cards. Update cardlists accordingly.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add decription of the allow_discard option added in commit
84597a44a9.
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
For ipu3 ImgU image processing, the frame data from TNR can feed into
DDR by Output Formatting System or feed into YUV downscaler to do YUV
downscaling for secondary output, which is usually used for display.
current ImgU image pipeline diagram misses the YUV downscaling,
this patch add it to aligh with actual hardware blocks.
Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Suggested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This patch add yavta test command in ipu3.rst as an example on how to
run simple ImgU test using yavta.
Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Add the media graph topologies for the i.MX6Q SabreSD and SabreAuto.
This makes it easier to understand the topology and follow the
entity descriptions in the following sections.
Also clarify that the SabreSD and SabreLite media pipeline config examples
are for the i.MX6Q boards.
Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Most of the driver-specific documentation is meant to help
users of the media subsystem.
Move them to the admin-guide.
It should be noticed, however, that several of those files
are outdated and will require further work in order to make
them useful again.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
- Fix the time_for_children symlink in /proc/$PID/ so it properly reflects
that it part of the 'time' namespace
- Add the missing userns limit for the allowed number of time namespaces,
which was half defined but the actual array member was not added. This
went unnoticed as the array has an exessive empty member at the end but
introduced a user visible regression as the output was corrupted.
- Prevent further silent ucount corruption by adding a BUILD_BUG_ON() to
catch half updated data.
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Merge tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time(keeping) updates from Thomas Gleixner:
- Fix the time_for_children symlink in /proc/$PID/ so it properly
reflects that it part of the 'time' namespace
- Add the missing userns limit for the allowed number of time
namespaces, which was half defined but the actual array member was
not added. This went unnoticed as the array has an exessive empty
member at the end but introduced a user visible regression as the
output was corrupted.
- Prevent further silent ucount corruption by adding a BUILD_BUG_ON()
to catch half updated data.
* tag 'timers-urgent-2020-04-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
ucount: Make sure ucounts in /proc/sys/user don't regress again
time/namespace: Add max_time_namespaces ucount
time/namespace: Fix time_for_children symlink
Merge yet more updates from Andrew Morton:
- Almost all of the rest of MM (memcg, slab-generic, slab, pagealloc,
gup, hugetlb, pagemap, memremap)
- Various other things (hfs, ocfs2, kmod, misc, seqfile)
* akpm: (34 commits)
ipc/util.c: sysvipc_find_ipc() should increase position index
kernel/gcov/fs.c: gcov_seq_next() should increase position index
fs/seq_file.c: seq_read(): add info message about buggy .next functions
drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings
change email address for Pali Rohár
selftests: kmod: test disabling module autoloading
selftests: kmod: fix handling test numbers above 9
docs: admin-guide: document the kernel.modprobe sysctl
fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
kmod: make request_module() return an error when autoloading is disabled
mm/memremap: set caching mode for PCI P2PDMA memory to WC
mm/memory_hotplug: add pgprot_t to mhp_params
powerpc/mm: thread pgprot_t through create_section_mapping()
x86/mm: introduce __set_memory_prot()
x86/mm: thread pgprot_t through init_memory_mapping()
mm/memory_hotplug: rename mhp_restrictions to mhp_params
mm/memory_hotplug: drop the flags field from struct mhp_restrictions
mm/special: create generic fallbacks for pte_special() and pte_mkspecial()
mm/vma: introduce VM_ACCESS_FLAGS
mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS
...
Document the kernel.modprobe sysctl in the same place that all the other
kernel.* sysctls are documented. Make sure to mention how to use this
sysctl to completely disable module autoloading, and how this sysctl
relates to CONFIG_STATIC_USERMODEHELPER.
[ebiggers@google.com: v5]
Link: http://lkml.kernel.org/r/20200318230515.171692-4-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jeff Vander Stoep <jeffv@google.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: NeilBrown <neilb@suse.com>
Link: http://lkml.kernel.org/r/20200312202552.241885-4-ebiggers@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 944d9fec8d ("hugetlb: add support for gigantic page allocation
at runtime") has added the run-time allocation of gigantic pages.
However it actually works only at early stages of the system loading,
when the majority of memory is free. After some time the memory gets
fragmented by non-movable pages, so the chances to find a contiguous 1GB
block are getting close to zero. Even dropping caches manually doesn't
help a lot.
At large scale rebooting servers in order to allocate gigantic hugepages
is quite expensive and complex. At the same time keeping some constant
percentage of memory in reserved hugepages even if the workload isn't
using it is a big waste: not all workloads can benefit from using 1 GB
pages.
The following solution can solve the problem:
1) On boot time a dedicated cma area* is reserved. The size is passed
as a kernel argument.
2) Run-time allocations of gigantic hugepages are performed using the
cma allocator and the dedicated cma area
In this case gigantic hugepages can be allocated successfully with a
high probability, however the memory isn't completely wasted if nobody
is using 1GB hugepages: it can be used for pagecache, anon memory, THPs,
etc.
* On a multi-node machine a per-node cma area is allocated on each node.
Following gigantic hugetlb allocation are using the first available
numa node if the mask isn't specified by a user.
Usage:
1) configure the kernel to allocate a cma area for hugetlb allocations:
pass hugetlb_cma=10G as a kernel argument
2) allocate hugetlb pages as usual, e.g.
echo 10 > /sys/kernel/mm/hugepages/hugepages-1048576kB/nr_hugepages
If the option isn't enabled or the allocation of the cma area failed,
the current behavior of the system is preserved.
x86 and arm-64 are covered by this patch, other architectures can be
trivially added later.
The patch contains clean-ups and fixes proposed and implemented by Aslan
Bakirov and Randy Dunlap. It also contains ideas and suggestions
proposed by Rik van Riel, Michal Hocko and Mike Kravetz. Thanks!
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Andreas Schaufler <andreas.schaufler@gmx.de>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Aslan Bakirov <aslan@fb.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Link: http://lkml.kernel.org/r/20200407163840.92263-3-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nicolas Dichtel
Mauro Carvalho Chehab
Waiman Long
Vlastimil Babka
Stephen Kitt
Hannes Reinecke
Heinz Mauelshagen
Emil Velikov
Changbin Du
Amit Daniel Kachhap
Paul E. McKenney
David S. Miller
Bingbu Cao
Rafael J. Wysocki
Linus Torvalds
Ronald G. Minnich
Alan Stern
Ingo Molnar
Fabio Estevam
Cristian Souza
Alexey Budankov
Eric Biggers
Milan Broz
Steve Longerbeam
Roman Gushchin