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Merge tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- correct panic handling when running as a Xen guest
- cleanup the Xen grant driver to remove printing a pointer being
always NULL
- remove a soon to be wrong call of of_dma_configure()
* tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: Stop abusing DT of_dma_configure API
xen/grant-table: remove unnecessary printing
x86/xen: Return from panic notifier
cgroup v2 introduces two memory protection thresholds: memory.low
(best-effort) and memory.min (hard protection). While they generally do
what they say on the tin, there is a limitation in their implementation
that makes them difficult to use effectively: that cliff behaviour often
manifests when they become eligible for reclaim. This patch implements
more intuitive and usable behaviour, where we gradually mount more
reclaim pressure as cgroups further and further exceed their protection
thresholds.
This cliff edge behaviour happens because we only choose whether or not
to reclaim based on whether the memcg is within its protection limits
(see the use of mem_cgroup_protected in shrink_node), but we don't vary
our reclaim behaviour based on this information. Imagine the following
timeline, with the numbers the lruvec size in this zone:
1. memory.low=1000000, memory.current=999999. 0 pages may be scanned.
2. memory.low=1000000, memory.current=1000000. 0 pages may be scanned.
3. memory.low=1000000, memory.current=1000001. 1000001* pages may be
scanned. (?!)
* Of course, we won't usually scan all available pages in the zone even
without this patch because of scan control priority, over-reclaim
protection, etc. However, as shown by the tests at the end, these
techniques don't sufficiently throttle such an extreme change in input,
so cliff-like behaviour isn't really averted by their existence alone.
Here's an example of how this plays out in practice. At Facebook, we are
trying to protect various workloads from "system" software, like
configuration management tools, metric collectors, etc (see this[0] case
study). In order to find a suitable memory.low value, we start by
determining the expected memory range within which the workload will be
comfortable operating. This isn't an exact science -- memory usage deemed
"comfortable" will vary over time due to user behaviour, differences in
composition of work, etc, etc. As such we need to ballpark memory.low,
but doing this is currently problematic:
1. If we end up setting it too low for the workload, it won't have
*any* effect (see discussion above). The group will receive the full
weight of reclaim and won't have any priority while competing with the
less important system software, as if we had no memory.low configured
at all.
2. Because of this behaviour, we end up erring on the side of setting
it too high, such that the comfort range is reliably covered. However,
protected memory is completely unavailable to the rest of the system,
so we might cause undue memory and IO pressure there when we *know* we
have some elasticity in the workload.
3. Even if we get the value totally right, smack in the middle of the
comfort zone, we get extreme jumps between no pressure and full
pressure that cause unpredictable pressure spikes in the workload due
to the current binary reclaim behaviour.
With this patch, we can set it to our ballpark estimation without too much
worry. Any undesirable behaviour, such as too much or too little reclaim
pressure on the workload or system will be proportional to how far our
estimation is off. This means we can set memory.low much more
conservatively and thus waste less resources *without* the risk of the
workload falling off a cliff if we overshoot.
As a more abstract technical description, this unintuitive behaviour
results in having to give high-priority workloads a large protection
buffer on top of their expected usage to function reliably, as otherwise
we have abrupt periods of dramatically increased memory pressure which
hamper performance. Having to set these thresholds so high wastes
resources and generally works against the principle of work conservation.
In addition, having proportional memory reclaim behaviour has other
benefits. Most notably, before this patch it's basically mandatory to set
memory.low to a higher than desirable value because otherwise as soon as
you exceed memory.low, all protection is lost, and all pages are eligible
to scan again. By contrast, having a gradual ramp in reclaim pressure
means that you now still get some protection when thresholds are exceeded,
which means that one can now be more comfortable setting memory.low to
lower values without worrying that all protection will be lost. This is
important because workingset size is really hard to know exactly,
especially with variable workloads, so at least getting *some* protection
if your workingset size grows larger than you expect increases user
confidence in setting memory.low without a huge buffer on top being
needed.
Thanks a lot to Johannes Weiner and Tejun Heo for their advice and
assistance in thinking about how to make this work better.
In testing these changes, I intended to verify that:
1. Changes in page scanning become gradual and proportional instead of
binary.
To test this, I experimented stepping further and further down
memory.low protection on a workload that floats around 19G workingset
when under memory.low protection, watching page scan rates for the
workload cgroup:
+------------+-----------------+--------------------+--------------+
| memory.low | test (pgscan/s) | control (pgscan/s) | % of control |
+------------+-----------------+--------------------+--------------+
| 21G | 0 | 0 | N/A |
| 17G | 867 | 3799 | 23% |
| 12G | 1203 | 3543 | 34% |
| 8G | 2534 | 3979 | 64% |
| 4G | 3980 | 4147 | 96% |
| 0 | 3799 | 3980 | 95% |
+------------+-----------------+--------------------+--------------+
As you can see, the test kernel (with a kernel containing this
patch) ramps up page scanning significantly more gradually than the
control kernel (without this patch).
2. More gradual ramp up in reclaim aggression doesn't result in
premature OOMs.
To test this, I wrote a script that slowly increments the number of
pages held by stress(1)'s --vm-keep mode until a production system
entered severe overall memory contention. This script runs in a highly
protected slice taking up the majority of available system memory.
Watching vmstat revealed that page scanning continued essentially
nominally between test and control, without causing forward reclaim
progress to become arrested.
[0]: https://facebookmicrosites.github.io/cgroup2/docs/overview.html#case-study-the-fbtax2-project
[akpm@linux-foundation.org: reflow block comments to fit in 80 cols]
[chris@chrisdown.name: handle cgroup_disable=memory when getting memcg protection]
Link: http://lkml.kernel.org/r/20190201045711.GA18302@chrisdown.name
Link: http://lkml.kernel.org/r/20190124014455.GA6396@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently execution of panic() continues until Xen's panic notifier
(xen_panic_event()) is called at which point we make a hypercall that
never returns.
This means that any notifier that is supposed to be called later as
well as significant part of panic() code (such as pstore writes from
kmsg_dump()) is never executed.
There is no reason for xen_panic_event() to be this last point in
execution since panic()'s emergency_restart() will call into
xen_emergency_restart() from where we can perform our hypercall.
Nevertheless, we will provide xen_legacy_crash boot option that will
preserve original behavior during crash. This option could be used,
for example, if running kernel dumper (which happens after panic
notifiers) is undesirable.
Reported-by: James Dingwall <james@dingwall.me.uk>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
Merge updates from Andrew Morton:
- a few hot fixes
- ocfs2 updates
- almost all of -mm (slab-generic, slab, slub, kmemleak, kasan,
cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug,
sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy,
oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap,
zsmalloc)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits)
mm/zsmalloc.c: fix a -Wunused-function warning
zswap: do not map same object twice
zswap: use movable memory if zpool support allocate movable memory
zpool: add malloc_support_movable to zpool_driver
shmem: fix obsolete comment in shmem_getpage_gfp()
mm/madvise: reduce code duplication in error handling paths
mm: mmap: increase sockets maximum memory size pgoff for 32bits
mm/mmap.c: refine find_vma_prev() with rb_last()
riscv: make mmap allocation top-down by default
mips: use generic mmap top-down layout and brk randomization
mips: replace arch specific way to determine 32bit task with generic version
mips: adjust brk randomization offset to fit generic version
mips: use STACK_TOP when computing mmap base address
mips: properly account for stack randomization and stack guard gap
arm: use generic mmap top-down layout and brk randomization
arm: use STACK_TOP when computing mmap base address
arm: properly account for stack randomization and stack guard gap
arm64, mm: make randomization selected by generic topdown mmap layout
arm64, mm: move generic mmap layout functions to mm
arm64: consider stack randomization for mmap base only when necessary
...
Cgroup v1 memcg controller has exposed a dedicated kmem limit to users
which turned out to be really a bad idea because there are paths which
cannot shrink the kernel memory usage enough to get below the limit (e.g.
because the accounted memory is not reclaimable). There are cases when
the failure is even not allowed (e.g. __GFP_NOFAIL). This means that the
kmem limit is in excess to the hard limit without any way to shrink and
thus completely useless. OOM killer cannot be invoked to handle the
situation because that would lead to a premature oom killing.
As a result many places might see ENOMEM returning from kmalloc and result
in unexpected errors. E.g. a global OOM killer when there is a lot of
free memory because ENOMEM is translated into VM_FAULT_OOM in #PF path and
therefore pagefault_out_of_memory would result in OOM killer.
Please note that the kernel memory is still accounted to the overall limit
along with the user memory so removing the kmem specific limit should
still allow to contain kernel memory consumption. Unlike the kmem one,
though, it invokes memory reclaim and targeted memcg oom killing if
necessary.
Start the deprecation process by crying to the kernel log. Let's see
whether there are relevant usecases and simply return to EINVAL in the
second stage if nobody complains in few releases.
[akpm@linux-foundation.org: tweak documentation text]
Link: http://lkml.kernel.org/r/20190911151612.GI4023@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Thomas Lindroth <thomas.lindroth@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The debug_pagealloc functionality is useful to catch buggy page allocator
users that cause e.g. use after free or double free. When page
inconsistency is detected, debugging is often simpler by knowing the call
stack of process that last allocated and freed the page. When page_owner
is also enabled, we record the allocation stack trace, but not freeing.
This patch therefore adds recording of freeing process stack trace to page
owner info, if both page_owner and debug_pagealloc are configured and
enabled. With only page_owner enabled, this info is not useful for the
memory leak debugging use case. dump_page() is adjusted to print the
info. An example result of calling __free_pages() twice may look like
this (note the page last free stack trace):
BUG: Bad page state in process bash pfn:13d8f8
page:ffffc31984f63e00 refcount:-1 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1affff800000000()
raw: 01affff800000000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 ffffffffffffffff 0000000000000000
page dumped because: nonzero _refcount
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xcc0(GFP_KERNEL)
prep_new_page+0x143/0x150
get_page_from_freelist+0x289/0x380
__alloc_pages_nodemask+0x13c/0x2d0
khugepaged+0x6e/0xc10
kthread+0xf9/0x130
ret_from_fork+0x3a/0x50
page last free stack trace:
free_pcp_prepare+0x134/0x1e0
free_unref_page+0x18/0x90
khugepaged+0x7b/0xc10
kthread+0xf9/0x130
ret_from_fork+0x3a/0x50
Modules linked in:
CPU: 3 PID: 271 Comm: bash Not tainted 5.3.0-rc4-2.g07a1a73-default+ #57
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x85/0xc0
bad_page.cold+0xba/0xbf
rmqueue_pcplist.isra.0+0x6c5/0x6d0
rmqueue+0x2d/0x810
get_page_from_freelist+0x191/0x380
__alloc_pages_nodemask+0x13c/0x2d0
__get_free_pages+0xd/0x30
__pud_alloc+0x2c/0x110
copy_page_range+0x4f9/0x630
dup_mmap+0x362/0x480
dup_mm+0x68/0x110
copy_process+0x19e1/0x1b40
_do_fork+0x73/0x310
__x64_sys_clone+0x75/0x80
do_syscall_64+0x6e/0x1e0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f10af854a10
...
Link: http://lkml.kernel.org/r/20190820131828.22684-5-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
implementation details that do not belong in DM crypt. The wrapper
template for ESSIV generation that was factored out will also be used
by fscrypt in the future.
- Add root hash pkcs#7 signature verification to the DM verity target.
- Add a new "clone" DM target that allows for efficient remote
replication of a device.
- Enhance DM bufio's cache to be tailored to each client based on use.
Clients that make heavy use of the cache get more of it, and those
that use less have reduced cache usage.
- Add a new DM_GET_TARGET_VERSION ioctl to allow userspace to query the
version number of a DM target (even if the associated module isn't yet
loaded).
- Fix invalid memory access in DM zoned target.
- Fix the max_discard_sectors limit advertised by the DM raid target; it
was mistakenly storing the limit in bytes rather than sectors.
- Small optimizations and cleanups in DM writecache target.
- Various fixes and cleanups in DM core, DM raid1 and space map portion
of DM persistent data library.
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Merge tag 'for-5.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- crypto and DM crypt advances that allow the crypto API to reclaim
implementation details that do not belong in DM crypt. The wrapper
template for ESSIV generation that was factored out will also be used
by fscrypt in the future.
- Add root hash pkcs#7 signature verification to the DM verity target.
- Add a new "clone" DM target that allows for efficient remote
replication of a device.
- Enhance DM bufio's cache to be tailored to each client based on use.
Clients that make heavy use of the cache get more of it, and those
that use less have reduced cache usage.
- Add a new DM_GET_TARGET_VERSION ioctl to allow userspace to query the
version number of a DM target (even if the associated module isn't
yet loaded).
- Fix invalid memory access in DM zoned target.
- Fix the max_discard_sectors limit advertised by the DM raid target;
it was mistakenly storing the limit in bytes rather than sectors.
- Small optimizations and cleanups in DM writecache target.
- Various fixes and cleanups in DM core, DM raid1 and space map portion
of DM persistent data library.
* tag 'for-5.4/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (22 commits)
dm: introduce DM_GET_TARGET_VERSION
dm bufio: introduce a global cache replacement
dm bufio: remove old-style buffer cleanup
dm bufio: introduce a global queue
dm bufio: refactor adjust_total_allocated
dm bufio: call adjust_total_allocated from __link_buffer and __unlink_buffer
dm: add clone target
dm raid: fix updating of max_discard_sectors limit
dm writecache: skip writecache_wait for pmem mode
dm stats: use struct_size() helper
dm crypt: omit parsing of the encapsulated cipher
dm crypt: switch to ESSIV crypto API template
crypto: essiv - create wrapper template for ESSIV generation
dm space map common: remove check for impossible sm_find_free() return value
dm raid1: use struct_size() with kzalloc()
dm writecache: optimize performance by sorting the blocks for writeback_all
dm writecache: add unlikely for getting two block with same LBA
dm writecache: remove unused member pointer in writeback_struct
dm zoned: fix invalid memory access
dm verity: add root hash pkcs#7 signature verification
...
Even in this age, people are still making new serial port silicon,
why...
Anyway, here's the TTY and Serial driver update for 5.4-rc1. Lots of
changes in here for a number of embedded serial port devices that are
being worked on because people really like to see those console logs...
Other than that, nothing major here, no core tty changes that anyone
should care about.
All of these have been in linux-next for a while with no reported
issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Even in this age, people are still making new serial port silicon,
why...
Anyway, here's the TTY and Serial driver update for 5.4-rc1. Lots of
changes in here for a number of embedded serial port devices that are
being worked on because people really like to see those console
logs...
Other than that, nothing major here, no core tty changes that anyone
should care about.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (125 commits)
serial: tegra: Add PIO mode support
serial: tegra: report clk rate errors
serial: tegra: add support to adjust baud rate
serial: tegra: DT for Adjusted baud rates
serial: tegra: add support to use 8 bytes trigger
serial: tegra: set maximum num of uart ports to 8
serial: tegra: check for FIFO mode enabled status
dt-binding: serial: tegra: add new chips
serial: tegra: report error to upper tty layer
serial: tegra: flush the RX fifo on frame error
serial: tegra: avoid reg access when clk disabled
serial: tegra: add support to ignore read
serial: sprd: correct the wrong sequence of arguments
dt-bindings: serial: Convert riscv,sifive-serial to json-schema
serial: max310x: turn off transmitter before activating AutoCTS or auto transmitter flow control
serial: max310x: Properly set flags in AutoCTS mode
tty: serial: fix platform_no_drv_owner.cocci warnings
dt-bindings: serial: Document Freescale LINFlexD UART
serial: fsl_linflexuart: Update compatible string
tty: n_gsm: avoid recursive locking with async port hangup
...
RST conversion is happily mostly behind us.
- A new document on reproducible builds.
- We finally got around to zapping the documentation for hardware support
that was removed in 2004; one doesn't want to rush these things.
- The usual assortment of fixes, typo corrections, etc.
You'll still find a handful of annoying conflicts against other trees,
mostly tied to the last RST conversions; resolutions are straightforward
and the linux-next ones are good.
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Merge tag 'docs-5.4' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"It's a somewhat calmer cycle for docs this time, as the churn of the
mass RST conversion is happily mostly behind us.
- A new document on reproducible builds.
- We finally got around to zapping the documentation for hardware
support that was removed in 2004; one doesn't want to rush these
things.
- The usual assortment of fixes, typo corrections, etc"
* tag 'docs-5.4' of git://git.lwn.net/linux: (67 commits)
Documentation: kbuild: Add document about reproducible builds
docs: printk-formats: Stop encouraging use of unnecessary %h[xudi] and %hh[xudi]
Documentation: Add "earlycon=sbi" to the admin guide
doc🔒 remove reference to clever use of read-write lock
devices.txt: improve entry for comedi (char major 98)
docs: mtd: Update spi nor reference driver
doc: arm64: fix grammar dtb placed in no attributes region
Documentation: sysrq: don't recommend 'S' 'U' before 'B'
mailmap: Update email address for Quentin Perret
docs: ftrace: clarify when tracing is disabled by the trace file
docs: process: fix broken link
Documentation/arm/samsung-s3c24xx: Remove stray U+FEFF character to fix title
Documentation/arm/sa1100/assabet: Fix 'make assabet_defconfig' command
Documentation/arm/sa1100: Remove some obsolete documentation
docs/zh_CN: update Chinese howto.rst for latexdocs making
Documentation: virt: Fix broken reference to virt tree's index
docs: Fix typo on pull requests guide
kernel-doc: Allow anonymous enum
Documentation: sphinx: Don't parse socket() as identifier reference
Documentation: sphinx: Add missing comma to list of strings
...
* ASUS WMI driver got couple of worth to mention updates, i.e. support of
FAN is fixed for recent products and the charge threshold support has been
added.
* Two uknown key events for Dell laptops are being ignored now to avoid spam
user with harmless messages.
* HP ZBook 17 G5 and ASUS Zenbook UX430UNR have got accelerometer support.
* Intel CherryTrail platforms got a regression with wake up. Now it's fixed.
* Intel PMC driver got fixed in order to work nicely in Xen environment.
* Intel Speed Select driver provides bucket vs core count relationship.
Besides that the tools has been updated for better output.
* The PrivacyGuard is enabled on Lenovo ThinkPad laptops.
* Three tablets, i.e. Trekstor Primebook C11B 2-in-1, Irbis TW90 and
Chuwi Surbook Mini, have got touchscreen support.
The following is an automated git shortlog grouped by driver:
acer-wmi:
- Switch to acpi_dev_get_first_match_dev()
asus-nb-wmi:
- Support ALS on the Zenbook UX430UNR
asus-wmi:
- Refactor charge threshold to use the battery hooking API
- Rename CHARGE_THRESHOLD to RSOC
- Reorder ASUS_WMI_CHARGE_THRESHOLD
- Fix condition in charge_threshold_store()
- Remove unnecessary blank lines
- Drop indentation level by inverting conditionals
- Use clamp_val() instead of open coded variant
- Replace sscanf() with kstrtoint()
- Refactor charge_threshold_store()
- Add support for charge threshold
- fix CPU fan control on recent products
- add a helper for device presence
- cleanup AGFN fan handling
- Use kmemdup rather than duplicating its implementation
compal-laptop:
- Initialize "value" in ec_read_u8()
dell-wmi:
- Use existing defined KBD_LED_* magic values
- Ignore keyboard backlight change KBD_LED_AUTO_TOKEN
- Ignore keyboard backlight change KBD_LED_ON_TOKEN
hp_accel:
- Add support for HP ZBook 17 G5
i2c-multi-instantiate:
- Use struct_size() helper
intel_bxtwc_tmu:
- Remove dev_err() usage after platform_get_irq()
intel_int0002_vgpio:
- Use device_init_wakeup
- Fix wakeups not working on Cherry Trail
- Remove dev_err() usage after platform_get_irq()
intel_pmc_core:
- Do not ioremap RAM
intel_pmc_core_pltdrv:
- Module removal warning fix
intel_pmc_ipc:
- Remove dev_err() usage after platform_get_irq()
ISST:
- Allow additional TRL MSRs
- Use dev_get_drvdata
MAINTAINERS:
- Switch PDx86 subsystem status to Odd Fixes
pcengines-apuv2:
- wire up simswitch gpio as led
- add mpcie reset gpio export
platform/mellanox:
- mlxreg-hotplug: Remove dev_err() usage after platform_get_irq()
pmc_atom:
- Add Siemens SIMATIC IPC227E to critclk_systems DMI table
thinkpad_acpi:
- Add ThinkPad PrivacyGuard
- Use kmemdup rather than duplicating its implementation
tools/power/x86/intel-speed-select:
- Display core count for bucket
- Fix memory leak
- Output success/failed for command output
- Output human readable CPU list
- Change turbo ratio output to maximum turbo frequency
- Switch output to MHz
- Simplify output for turbo-freq and base-freq
- Fix cpu-count output
- Fix help option typo
- Fix package typo
- Fix a read overflow in isst_set_tdp_level_msr()
touchscreen_dmi:
- Add info for the Trekstor Primebook C11B 2-in-1
- Add info for the Irbis TW90 tablet
- Add info for the Chuwi Surbook Mini tablet
wmi:
- Remove acpi_has_method() call
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Merge tag 'platform-drivers-x86-v5.4-1' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform-drivers updates from Andy Shevchenko:
- ASUS WMI driver got a couple of updates, i.e. support of FAN is fixed
for recent products and the charge threshold support has been added
- Two uknown key events for Dell laptops are being ignored now to avoid
spamming users with harmless messages
- HP ZBook 17 G5 and ASUS Zenbook UX430UNR got accelerometer support.
- Intel CherryTrail platforms had a regression with wake up. Now it's
fixed
- Intel PMC driver got fixed in order to work nicely in Xen
environment
- Intel Speed Select driver provides bucket vs core count relationship.
Besides that the tools has been updated for better output
- The PrivacyGuard is enabled on Lenovo ThinkPad laptops
- Three tablets - Trekstor Primebook C11B 2-in-1, Irbis TW90 and Chuwi
Surbook Mini - got touchscreen support
* tag 'platform-drivers-x86-v5.4-1' of git://git.infradead.org/linux-platform-drivers-x86: (53 commits)
MAINTAINERS: Switch PDx86 subsystem status to Odd Fixes
platform/x86: asus-wmi: Refactor charge threshold to use the battery hooking API
platform/x86: asus-wmi: Rename CHARGE_THRESHOLD to RSOC
platform/x86: asus-wmi: Reorder ASUS_WMI_CHARGE_THRESHOLD
tools/power/x86/intel-speed-select: Display core count for bucket
platform/x86: ISST: Allow additional TRL MSRs
tools/power/x86/intel-speed-select: Fix memory leak
tools/power/x86/intel-speed-select: Output success/failed for command output
tools/power/x86/intel-speed-select: Output human readable CPU list
tools/power/x86/intel-speed-select: Change turbo ratio output to maximum turbo frequency
tools/power/x86/intel-speed-select: Switch output to MHz
tools/power/x86/intel-speed-select: Simplify output for turbo-freq and base-freq
tools/power/x86/intel-speed-select: Fix cpu-count output
tools/power/x86/intel-speed-select: Fix help option typo
tools/power/x86/intel-speed-select: Fix package typo
tools/power/x86/intel-speed-select: Fix a read overflow in isst_set_tdp_level_msr()
platform/x86: intel_int0002_vgpio: Use device_init_wakeup
platform/x86: intel_int0002_vgpio: Fix wakeups not working on Cherry Trail
platform/x86: compal-laptop: Initialize "value" in ec_read_u8()
platform/x86: touchscreen_dmi: Add info for the Trekstor Primebook C11B 2-in-1
...
Pull scheduler updates from Ingo Molnar:
- MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.
As perf and the scheduler is getting bigger and more complex,
document the status quo of current responsibilities and interests,
and spread the review pain^H^H^H^H fun via an increase in the Cc:
linecount generated by scripts/get_maintainer.pl. :-)
- Add another series of patches that brings the -rt (PREEMPT_RT) tree
closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
into a new CONFIG_PREEMPTION category that will allow the eventual
introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
to go though.
- Extend the CPU cgroup controller with uclamp.min and uclamp.max to
allow the finer shaping of CPU bandwidth usage.
- Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).
- Improve the behavior of high CPU count, high thread count
applications running under cpu.cfs_quota_us constraints.
- Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.
- Improve CPU isolation housekeeping CPU allocation NUMA locality.
- Fix deadline scheduler bandwidth calculations and logic when cpusets
rebuilds the topology, or when it gets deadline-throttled while it's
being offlined.
- Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
setscheduler() system calls without creating global serialization.
Add new synchronization between cpuset topology-changing events and
the deadline acceptance tests in setscheduler(), which were broken
before.
- Rework the active_mm state machine to be less confusing and more
optimal.
- Rework (simplify) the pick_next_task() slowpath.
- Improve load-balancing on AMD EPYC systems.
- ... and misc cleanups, smaller fixes and improvements - please see
the Git log for more details.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
sched/psi: Correct overly pessimistic size calculation
sched/fair: Speed-up energy-aware wake-ups
sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
sched/uclamp: Update CPU's refcount on TG's clamp changes
sched/uclamp: Use TG's clamps to restrict TASK's clamps
sched/uclamp: Propagate system defaults to the root group
sched/uclamp: Propagate parent clamps
sched/uclamp: Extend CPU's cgroup controller
sched/topology: Improve load balancing on AMD EPYC systems
arch, ia64: Make NUMA select SMP
sched, perf: MAINTAINERS update, add submaintainers and reviewers
sched/fair: Use rq_lock/unlock in online_fair_sched_group
cpufreq: schedutil: fix equation in comment
sched: Rework pick_next_task() slow-path
sched: Allow put_prev_task() to drop rq->lock
sched/fair: Expose newidle_balance()
sched: Add task_struct pointer to sched_class::set_curr_task
sched: Rework CPU hotplug task selection
sched/{rt,deadline}: Fix set_next_task vs pick_next_task
sched: Fix kerneldoc comment for ia64_set_curr_task
...
Pull RCU updates from Ingo Molnar:
"This cycle's RCU changes were:
- A few more RCU flavor consolidation cleanups.
- Updates to RCU's list-traversal macros improving lockdep usability.
- Forward-progress improvements for no-CBs CPUs: Avoid ignoring
incoming callbacks during grace-period waits.
- Forward-progress improvements for no-CBs CPUs: Use ->cblist
structure to take advantage of others' grace periods.
- Also added a small commit that avoids needlessly inflicting
scheduler-clock ticks on callback-offloaded CPUs.
- Forward-progress improvements for no-CBs CPUs: Reduce contention on
->nocb_lock guarding ->cblist.
- Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
list to further reduce contention on ->nocb_lock guarding ->cblist.
- Miscellaneous fixes.
- Torture-test updates.
- minor LKMM updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits)
MAINTAINERS: Update from paulmck@linux.ibm.com to paulmck@kernel.org
rcu: Don't include <linux/ktime.h> in rcutiny.h
rcu: Allow rcu_do_batch() to dynamically adjust batch sizes
rcu/nocb: Don't wake no-CBs GP kthread if timer posted under overload
rcu/nocb: Reduce __call_rcu_nocb_wake() leaf rcu_node ->lock contention
rcu/nocb: Reduce nocb_cb_wait() leaf rcu_node ->lock contention
rcu/nocb: Advance CBs after merge in rcutree_migrate_callbacks()
rcu/nocb: Avoid synchronous wakeup in __call_rcu_nocb_wake()
rcu/nocb: Print no-CBs diagnostics when rcutorture writer unduly delayed
rcu/nocb: EXP Check use and usefulness of ->nocb_lock_contended
rcu/nocb: Add bypass callback queueing
rcu/nocb: Atomic ->len field in rcu_segcblist structure
rcu/nocb: Unconditionally advance and wake for excessive CBs
rcu/nocb: Reduce ->nocb_lock contention with separate ->nocb_gp_lock
rcu/nocb: Reduce contention at no-CBs invocation-done time
rcu/nocb: Reduce contention at no-CBs registry-time CB advancement
rcu/nocb: Round down for number of no-CBs grace-period kthreads
rcu/nocb: Avoid ->nocb_lock capture by corresponding CPU
rcu/nocb: Avoid needless wakeups of no-CBs grace-period kthread
rcu/nocb: Make __call_rcu_nocb_wake() safe for many callbacks
...
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Merge tag 'please-pull-ia64_for_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
Pull ia64 updates from Tony Luck:
"The big change here is removal of support for SGI Altix"
* tag 'please-pull-ia64_for_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: (33 commits)
genirq: remove the is_affinity_mask_valid hook
ia64: remove CONFIG_SWIOTLB ifdefs
ia64: remove support for machvecs
ia64: move the screen_info setup to common code
ia64: move the ROOT_DEV setup to common code
ia64: rework iommu probing
ia64: remove the unused sn_coherency_id symbol
ia64: remove the SGI UV simulator support
ia64: remove the zx1 swiotlb machvec
ia64: remove CONFIG_ACPI ifdefs
ia64: remove CONFIG_PCI ifdefs
ia64: remove the hpsim platform
ia64: remove now unused machvec indirections
ia64: remove support for the SGI SN2 platform
drivers: remove the SGI SN2 IOC4 base support
drivers: remove the SGI SN2 IOC3 base support
qla2xxx: remove SGI SN2 support
qla1280: remove SGI SN2 support
misc/sgi-xp: remove SGI SN2 support
char/mspec: remove SGI SN2 support
...
- 52-bit virtual addressing in the kernel
- New ABI to allow tagged user pointers to be dereferenced by syscalls
- Early RNG seeding by the bootloader
- Improve robustness of SMP boot
- Fix TLB invalidation in light of recent architectural clarifications
- Support for i.MX8 DDR PMU
- Remove direct LSE instruction patching in favour of static keys
- Function error injection using kprobes
- Support for the PPTT "thread" flag introduced by ACPI 6.3
- Move PSCI idle code into proper cpuidle driver
- Relaxation of implicit I/O memory barriers
- Build with RELR relocations when toolchain supports them
- Numerous cleanups and non-critical fixes
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Although there isn't tonnes of code in terms of line count, there are
a fair few headline features which I've noted both in the tag and also
in the merge commits when I pulled everything together.
The part I'm most pleased with is that we had 35 contributors this
time around, which feels like a big jump from the usual small group of
core arm64 arch developers. Hopefully they all enjoyed it so much that
they'll continue to contribute, but we'll see.
It's probably worth highlighting that we've pulled in a branch from
the risc-v folks which moves our CPU topology code out to where it can
be shared with others.
Summary:
- 52-bit virtual addressing in the kernel
- New ABI to allow tagged user pointers to be dereferenced by
syscalls
- Early RNG seeding by the bootloader
- Improve robustness of SMP boot
- Fix TLB invalidation in light of recent architectural
clarifications
- Support for i.MX8 DDR PMU
- Remove direct LSE instruction patching in favour of static keys
- Function error injection using kprobes
- Support for the PPTT "thread" flag introduced by ACPI 6.3
- Move PSCI idle code into proper cpuidle driver
- Relaxation of implicit I/O memory barriers
- Build with RELR relocations when toolchain supports them
- Numerous cleanups and non-critical fixes"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (114 commits)
arm64: remove __iounmap
arm64: atomics: Use K constraint when toolchain appears to support it
arm64: atomics: Undefine internal macros after use
arm64: lse: Make ARM64_LSE_ATOMICS depend on JUMP_LABEL
arm64: asm: Kill 'asm/atomic_arch.h'
arm64: lse: Remove unused 'alt_lse' assembly macro
arm64: atomics: Remove atomic_ll_sc compilation unit
arm64: avoid using hard-coded registers for LSE atomics
arm64: atomics: avoid out-of-line ll/sc atomics
arm64: Use correct ll/sc atomic constraints
jump_label: Don't warn on __exit jump entries
docs/perf: Add documentation for the i.MX8 DDR PMU
perf/imx_ddr: Add support for AXI ID filtering
arm64: kpti: ensure patched kernel text is fetched from PoU
arm64: fix fixmap copy for 16K pages and 48-bit VA
perf/smmuv3: Validate groups for global filtering
perf/smmuv3: Validate group size
arm64: Relax Documentation/arm64/tagged-pointers.rst
arm64: kvm: Replace hardcoded '1' with SYS_PAR_EL1_F
arm64: mm: Ignore spurious translation faults taken from the kernel
...
This argument is supported on RISC-V systems and widely used, but was
not documented here.
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Describe how the comedi minor device numbers are split across comedi
devices and comedi subdevices.
Replace the current, long dead URL with an official URL for the Comedi
project.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add the dm-clone target, which allows cloning of arbitrary block
devices.
dm-clone produces a one-to-one copy of an existing, read-only source
device into a writable destination device: It presents a virtual block
device which makes all data appear immediately, and redirects reads and
writes accordingly.
The main use case of dm-clone is to clone a potentially remote,
high-latency, read-only, archival-type block device into a writable,
fast, primary-type device for fast, low-latency I/O. The cloned device
is visible/mountable immediately and the copy of the source device to
the destination device happens in the background, in parallel with user
I/O.
When the cloning completes, the dm-clone table can be removed altogether
and be replaced, e.g., by a linear table, mapping directly to the
destination device.
For further information and examples of how to use dm-clone, please read
Documentation/admin-guide/device-mapper/dm-clone.rst
Suggested-by: Vangelis Koukis <vkoukis@arrikto.com>
Co-developed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Nikos Tsironis <ntsironis@arrikto.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This adds a helper to check whether a device needs to
use bounce buffer. It also provides a boot time option
to disable the bounce buffer. Users can use this to
prevent the iommu driver from using the bounce buffer
for performance gain.
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Tested-by: Xu Pengfei <pengfei.xu@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This feature is found optionally in T480s, T490, T490s.
The feature is called lcdshadow and visible via
/proc/acpi/ibm/lcdshadow.
The ACPI methods \_SB.PCI0.LPCB.EC.HKEY.{GSSS,SSSS,TSSS,CSSS} are
available in these machines. They get, set, toggle or change the state
apparently.
The patch was tested on a 5.0 series kernel on a T480s.
Signed-off-by: Alexander Schremmer <alex@alexanderweb.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This advice is obsolete and slightly harmful for filesystems from this
millenium: any modern filesystem can handle unexpected crashes without
requiring fsck -- and on the other hand, trying to write to the disk when
the kernel is in a bad state risks introducing corruption.
For ext2, any unsafe shutdown meant widespread breakage, but it's no longer
a reasonable filesystem for any non-special use.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Introduce two options to control the use of the tlbie instruction. A
boot time option which completely disables the kernel using the
instruction, this is currently incompatible with HASH MMU, KVM, and
coherent accelerators.
And a debugfs option can be switched at runtime and avoids using tlbie
for invalidating CPU TLBs for normal process and kernel address
mappings. Coherent accelerators are still managed with tlbie, as will
KVM partition scope translations.
Cross-CPU TLB flushing is implemented with IPIs and tlbiel. This is a
basic implementation which does not attempt to make any optimisation
beyond the tlbie implementation.
This is useful for performance testing among other things. For example
in certain situations on large systems, using IPIs may be faster than
tlbie as they can be directed rather than broadcast. Later we may also
take advantage of the IPIs to do more interesting things such as trim
the mm cpumask more aggressively.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-7-npiggin@gmail.com
Introduce support for LINFlex driver, based on:
- the version of Freescale LPUART driver after commit b3e3bf2ef2 ("Merge
4.0-rc7 into tty-next");
- commit abf1e0a980 ("tty: serial: fsl_lpuart: lock port on console
write").
In this basic version, the driver can be tested using initramfs and relies
on the clocks and pin muxing set up by U-Boot.
Remarks concerning the earlycon support:
- LinFlexD does not allow character transmissions in the INIT mode (see
section 47.4.2.1 in the reference manual[1]). Therefore, a mutual
exclusion between the first linflex_setup_watermark/linflex_set_termios
executions and linflex_earlycon_putchar was employed and the characters
normally sent to earlycon during initialization are kept in a buffer and
sent afterwards.
- Empirically, character transmission is also forbidden within the last 1-2
ms before entering the INIT mode, so we use an explicit timeout
(PREINIT_DELAY) between linflex_earlycon_putchar and the first call to
linflex_setup_watermark.
- U-Boot currently uses the UART FIFO mode, while this driver makes the
transition to the buffer mode. Therefore, the earlycon putchar function
matches the U-Boot behavior before initializations and the Linux behavior
after.
[1] https://www.nxp.com/webapp/Download?colCode=S32V234RM
Signed-off-by: Stoica Cosmin-Stefan <cosmin.stoica@nxp.com>
Signed-off-by: Adrian.Nitu <adrian.nitu@freescale.com>
Signed-off-by: Larisa Grigore <Larisa.Grigore@nxp.com>
Signed-off-by: Ana Nedelcu <B56683@freescale.com>
Signed-off-by: Mihaela Martinas <Mihaela.Martinas@freescale.com>
Signed-off-by: Matthew Nunez <matthew.nunez@nxp.com>
[stefan-gabriel.mirea@nxp.com: Reduced for upstreaming and implemented
earlycon support]
Signed-off-by: Stefan-Gabriel Mirea <stefan-gabriel.mirea@nxp.com>
Link: https://lore.kernel.org/r/20190809112853.15846-6-stefan-gabriel.mirea@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This argument was not being considered since blk-mq was set by default,
so removed this documentation to avoid confusion.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
.txt file is now .rst
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Since the inclusion of blk-mq, elevator argument was not being
considered anymore, and it's utility died long with the legacy IO path,
now removed too.
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@gmail.com>
Fold with doc removal patch.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The cgroup CPU bandwidth controller allows to assign a specified
(maximum) bandwidth to the tasks of a group. However this bandwidth is
defined and enforced only on a temporal base, without considering the
actual frequency a CPU is running on. Thus, the amount of computation
completed by a task within an allocated bandwidth can be very different
depending on the actual frequency the CPU is running that task.
The amount of computation can be affected also by the specific CPU a
task is running on, especially when running on asymmetric capacity
systems like Arm's big.LITTLE.
With the availability of schedutil, the scheduler is now able
to drive frequency selections based on actual task utilization.
Moreover, the utilization clamping support provides a mechanism to
bias the frequency selection operated by schedutil depending on
constraints assigned to the tasks currently RUNNABLE on a CPU.
Giving the mechanisms described above, it is now possible to extend the
cpu controller to specify the minimum (or maximum) utilization which
should be considered for tasks RUNNABLE on a cpu.
This makes it possible to better defined the actual computational
power assigned to task groups, thus improving the cgroup CPU bandwidth
controller which is currently based just on time constraints.
Extend the CPU controller with a couple of new attributes uclamp.{min,max}
which allow to enforce utilization boosting and capping for all the
tasks in a group.
Specifically:
- uclamp.min: defines the minimum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run at least at a
minimum frequency which corresponds to the uclamp.min
utilization
- uclamp.max: defines the maximum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run up to a
maximum frequency which corresponds to the uclamp.max
utilization
These attributes:
a) are available only for non-root nodes, both on default and legacy
hierarchies, while system wide clamps are defined by a generic
interface which does not depends on cgroups. This system wide
interface enforces constraints on tasks in the root node.
b) enforce effective constraints at each level of the hierarchy which
are a restriction of the group requests considering its parent's
effective constraints. Root group effective constraints are defined
by the system wide interface.
This mechanism allows each (non-root) level of the hierarchy to:
- request whatever clamp values it would like to get
- effectively get only up to the maximum amount allowed by its parent
c) have higher priority than task-specific clamps, defined via
sched_setattr(), thus allowing to control and restrict task requests.
Add two new attributes to the cpu controller to collect "requested"
clamp values. Allow that at each non-root level of the hierarchy.
Keep it simple by not caring now about "effective" values computation
and propagation along the hierarchy.
Update sysctl_sched_uclamp_handler() to use the newly introduced
uclamp_mutex so that we serialize system default updates with cgroup
relate updates.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-2-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* for-next/52-bit-kva: (25 commits)
Support for 52-bit virtual addressing in kernel space
* for-next/cpu-topology: (9 commits)
Move CPU topology parsing into core code and add support for ACPI 6.3
* for-next/error-injection: (2 commits)
Support for function error injection via kprobes
* for-next/perf: (8 commits)
Support for i.MX8 DDR PMU and proper SMMUv3 group validation
* for-next/psci-cpuidle: (7 commits)
Move PSCI idle code into a new CPUidle driver
* for-next/rng: (4 commits)
Support for 'rng-seed' property being passed in the devicetree
* for-next/smpboot: (3 commits)
Reduce fragility of secondary CPU bringup in debug configurations
* for-next/tbi: (10 commits)
Introduce new syscall ABI with relaxed requirements for pointer tags
* for-next/tlbi: (6 commits)
Handle spurious page faults arising from kernel space
Make the Enter-Secure-Mode (ESM) ultravisor call to switch the VM to secure
mode. Pass kernel base address and FDT address so that the Ultravisor is
able to verify the integrity of the VM using information from the ESM blob.
Add "svm=" command line option to turn on switching to secure mode.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[ andmike: Generate an RTAS os-term hcall when the ESM ucall fails. ]
Signed-off-by: Michael Anderson <andmike@linux.ibm.com>
[ bauerman: Cleaned up the code a bit. ]
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-5-bauerman@linux.ibm.com
Add a script which can be used to generate device-specific iocost
linear model coefficients.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patchset implements IO cost model based work-conserving
proportional controller.
While io.latency provides the capability to comprehensively prioritize
and protect IOs depending on the cgroups, its protection is binary -
the lowest latency target cgroup which is suffering is protected at
the cost of all others. In many use cases including stacking multiple
workload containers in a single system, it's necessary to distribute
IO capacity with better granularity.
One challenge of controlling IO resources is the lack of trivially
observable cost metric. The most common metrics - bandwidth and iops
- can be off by orders of magnitude depending on the device type and
IO pattern. However, the cost isn't a complete mystery. Given
several key attributes, we can make fairly reliable predictions on how
expensive a given stream of IOs would be, at least compared to other
IO patterns.
The function which determines the cost of a given IO is the IO cost
model for the device. This controller distributes IO capacity based
on the costs estimated by such model. The more accurate the cost
model the better but the controller adapts based on IO completion
latency and as long as the relative costs across differents IO
patterns are consistent and sensible, it'll adapt to the actual
performance of the device.
Currently, the only implemented cost model is a simple linear one with
a few sets of default parameters for different classes of device.
This covers most common devices reasonably well. All the
infrastructure to tune and add different cost models is already in
place and a later patch will also allow using bpf progs for cost
models.
Please see the top comment in blk-iocost.c and documentation for
more details.
v2: Rebased on top of RQ_ALLOC_TIME changes and folded in Rik's fix
for a divide-by-zero bug in current_hweight() triggered by zero
inuse_sum.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Andy Newell <newella@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add some documentation describing the DDR PMU residing in the Freescale
i.MDX SoC and its perf driver implementation in Linux.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Will Deacon <will@kernel.org>
Pull x86 fixes from Thomas Gleixner:
"A few fixes for x86:
- Fix a boot regression caused by the recent bootparam sanitizing
change, which escaped the attention of all people who reviewed that
code.
- Address a boot problem on machines with broken E820 tables caused
by an underflow which ended up placing the trampoline start at
physical address 0.
- Handle machines which do not advertise a legacy timer of any form,
but need calibration of the local APIC timer gracefully by making
the calibration routine independent from the tick interrupt. Marked
for stable as well as there seems to be quite some new laptops
rolled out which expose this.
- Clear the RDRAND CPUID bit on AMD family 15h and 16h CPUs which are
affected by broken firmware which does not initialize RDRAND
correctly after resume. Add a command line parameter to override
this for machine which either do not use suspend/resume or have a
fixed BIOS. Unfortunately there is no way to detect this on boot,
so the only safe decision is to turn it off by default.
- Prevent RFLAGS from being clobbers in CALL_NOSPEC on 32bit which
caused fast KVM instruction emulation to break.
- Explain the Intel CPU model naming convention so that the repeating
discussions come to an end"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/retpoline: Don't clobber RFLAGS during CALL_NOSPEC on i386
x86/boot: Fix boot regression caused by bootparam sanitizing
x86/CPU/AMD: Clear RDRAND CPUID bit on AMD family 15h/16h
x86/boot/compressed/64: Fix boot on machines with broken E820 table
x86/apic: Handle missing global clockevent gracefully
x86/cpu: Explain Intel model naming convention
The verification is to support cases where the root hash is not secured
by Trusted Boot, UEFI Secureboot or similar technologies.
One of the use cases for this is for dm-verity volumes mounted after
boot, the root hash provided during the creation of the dm-verity volume
has to be secure and thus in-kernel validation implemented here will be
used before we trust the root hash and allow the block device to be
created.
The signature being provided for verification must verify the root hash
and must be trusted by the builtin keyring for verification to succeed.
The hash is added as a key of type "user" and the description is passed
to the kernel so it can look it up and use it for verification.
Adds CONFIG_DM_VERITY_VERIFY_ROOTHASH_SIG which can be turned on if root
hash verification is needed.
Kernel commandline dm_verity module parameter 'require_signatures' will
indicate whether to force root hash signature verification (for all dm
verity volumes).
Signed-off-by: Jaskaran Khurana <jaskarankhurana@linux.microsoft.com>
Tested-and-Reviewed-by: Milan Broz <gmazyland@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull RCU and LKMM changes from Paul E. McKenney:
- A few more RCU flavor consolidation cleanups.
- Miscellaneous fixes.
- Updates to RCU's list-traversal macros improving lockdep usability.
- Torture-test updates.
- Forward-progress improvements for no-CBs CPUs: Avoid ignoring
incoming callbacks during grace-period waits.
- Forward-progress improvements for no-CBs CPUs: Use ->cblist
structure to take advantage of others' grace periods.
- Also added a small commit that avoids needlessly inflicting
scheduler-clock ticks on callback-offloaded CPUs.
- Forward-progress improvements for no-CBs CPUs: Reduce contention
on ->nocb_lock guarding ->cblist.
- Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
list to further reduce contention on ->nocb_lock guarding ->cblist.
- LKMM updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While existing LSMs can be extended to handle lockdown policy,
distributions generally want to be able to apply a straightforward
static policy. This patch adds a simple LSM that can be configured to
reject either integrity or all lockdown queries, and can be configured
at runtime (through securityfs), boot time (via a kernel parameter) or
build time (via a kconfig option). Based on initial code by David
Howells.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
There have been reports of RDRAND issues after resuming from suspend on
some AMD family 15h and family 16h systems. This issue stems from a BIOS
not performing the proper steps during resume to ensure RDRAND continues
to function properly.
RDRAND support is indicated by CPUID Fn00000001_ECX[30]. This bit can be
reset by clearing MSR C001_1004[62]. Any software that checks for RDRAND
support using CPUID, including the kernel, will believe that RDRAND is
not supported.
Update the CPU initialization to clear the RDRAND CPUID bit for any family
15h and 16h processor that supports RDRAND. If it is known that the family
15h or family 16h system does not have an RDRAND resume issue or that the
system will not be placed in suspend, the "rdrand=force" kernel parameter
can be used to stop the clearing of the RDRAND CPUID bit.
Additionally, update the suspend and resume path to save and restore the
MSR C001_1004 value to ensure that the RDRAND CPUID setting remains in
place after resuming from suspend.
Note, that clearing the RDRAND CPUID bit does not prevent a processor
that normally supports the RDRAND instruction from executing it. So any
code that determined the support based on family and model won't #UD.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chen Yu <yu.c.chen@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>
Cc: "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: <stable@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "x86@kernel.org" <x86@kernel.org>
Link: https://lkml.kernel.org/r/7543af91666f491547bd86cebb1e17c66824ab9f.1566229943.git.thomas.lendacky@amd.com
The aim of this machvec is to support devices with < 32-bit dma
masks. But given that ia64 only has a ZONE_DMA32 and not a ZONE_DMA
that isn't supported by swiotlb either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190813072514.23299-21-hch@lst.de
Signed-off-by: Tony Luck <tony.luck@intel.com>
This commit changes the name of the rcu_nocb_leader_stride kernel
boot parameter to rcu_nocb_gp_stride in order to account for the new
distinction between callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Both IPX and TR have not been supported for a while now.
Remove them from the /proc/sys/net documentation.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The "pci=resource_alignment" parameter is described as requiring an order
(not a size) and the code in pci_specified_resource_alignment() expects an
order.
But the example wrongly shows a size. Convert the example to an order.
Fixes: 8b078c6032 ("PCI: Update "pci=resource_alignment" documentation")
Link: https://lore.kernel.org/r/20190606032557.107542-1-aik@ozlabs.ru
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Add documentation to the Spectre document about the new swapgs variant of
Spectre v1.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit adds a rcu_cpu_stall_ftrace_dump kernel boot parameter, that,
when set, causes the trace buffer to be dumped after an RCU CPU stall
warning is printed. This kernel boot parameter is disabled by default,
maintaining compatibility with previous behavior.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The filenames for cifs documentation is not using the same
convention as almost all Kernel documents is using. So,
rename them to a more appropriate name. Then, manually convert
the documentation files for CIFS to ReST.
By doing a manual conversion, we can preserve the original
author's style, while making it to look more like the other
Kernel documents.
Most of the conversion here is trivial. The most complex one was
the README file (which was renamed to usage.rst).
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Linus Torvalds