LoongArch already supports two crashkernel regions in kexec-tools, so we
can directly use the common interface to support crashkernel=X,[high,low]
after commit 0ab97169aa ("crash_core: add generic function to do
reservation").
With the help of newly changed function parse_crashkernel() and generic
reserve_crashkernel_generic(), crashkernel reservation can be simplified
by steps:
1) Add a new header file <asm/crash_core.h>, then define CRASH_ALIGN,
CRASH_ADDR_LOW_MAX and CRASH_ADDR_HIGH_MAX and in <asm/crash_core.h>;
2) Add arch_reserve_crashkernel() to call parse_crashkernel() and
reserve_crashkernel_generic();
3) Add ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION Kconfig in
arch/loongarch/Kconfig.
One can reserve the crash kernel from high memory above DMA zone range
by explicitly passing "crashkernel=X,high"; or reserve a memory range
below 4G with "crashkernel=X,low". Besides, there are few rules need to
take notice:
1) "crashkernel=X,[high,low]" will be ignored if "crashkernel=size" is
specified.
2) "crashkernel=X,low" is valid only when "crashkernel=X,high" is passed
and there is enough memory to be allocated under 4G.
3) When allocating crashkernel above 4G and no "crashkernel=X,low" is
specified, a 128M low memory will be allocated automatically for
swiotlb bounce buffer.
See Documentation/admin-guide/kernel-parameters.txt for more information.
Following test cases have been performed as expected:
1) crashkernel=256M //low=256M
2) crashkernel=1G //low=1G
3) crashkernel=4G //high=4G, low=128M(default)
4) crashkernel=4G crashkernel=256M,high //high=4G, low=128M(default), high is ignored
5) crashkernel=4G crashkernel=256M,low //high=4G, low=128M(default), low is ignored
6) crashkernel=4G,high //high=4G, low=128M(default)
7) crashkernel=256M,low //low=0M, invalid
8) crashkernel=4G,high crashkernel=256M,low //high=4G, low=256M
9) crashkernel=4G,high crashkernel=4G,low //high=0M, low=0M, invalid
10) crashkernel=512M@2560M //low=512M
11) crashkernel=1G,high crashkernel=0M,low //high=1G, low=0M
Recommended usage in general:
1) In the case of small memory: crashkernel=512M
2) In the case of large memory: crashkernel=1024M,high crashkernel=128M,low
Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Pull RCU updates from Neeraj Upadhyay:
- Documentation and comment updates
- RCU torture, locktorture updates that include cleanups; nolibc init
build support for mips, ppc and rv64; testing of mid stall duration
scenario and fixing fqs task creation conditions
- Misc fixes, most notably restricting usage of RCU CPU stall
notifiers, to confine their usage primarily to debug kernels
- RCU tasks minor fixes
- lockdep annotation fix for NMI-safe accesses, callback
advancing/acceleration cleanup and documentation improvements
* tag 'rcu.release.v6.8' of https://github.com/neeraju/linux:
rcu: Force quiescent states only for ongoing grace period
doc: Clarify historical disclaimers in memory-barriers.txt
doc: Mention address and data dependencies in rcu_dereference.rst
doc: Clarify RCU Tasks reader/updater checklist
rculist.h: docs: Fix wrong function summary
Documentation: RCU: Remove repeated word in comments
srcu: Use try-lock lockdep annotation for NMI-safe access.
srcu: Explain why callbacks invocations can't run concurrently
srcu: No need to advance/accelerate if no callback enqueued
srcu: Remove superfluous callbacks advancing from srcu_gp_start()
rcu: Remove unused macros from rcupdate.h
rcu: Restrict access to RCU CPU stall notifiers
rcu-tasks: Mark RCU Tasks accesses to current->rcu_tasks_idle_cpu
rcutorture: Add fqs_holdoff check before fqs_task is created
rcutorture: Add mid-sized stall to TREE07
rcutorture: add nolibc init support for mips, ppc and rv64
locktorture: Increase Hamming distance between call_rcu_chain and rcu_call_chains
Pull media updates from Mauro Carvalho Chehab:
- v4l core: subdev frame interval now supports which field
- v4l kapi: moves and renames the init_cfg pad op to init_state as an
internal op.
- new sensor drivers: gc0308, gc2145, Avnet Alvium, ov64a40, tw9900
- new camera driver: STM32 DCMIPP
- s5p-mfc has gained MFC v12 support
- new ISP driver added to staging: Starfive
- new stateful encoder/decoded: Wave5 codec It is found on the J721S2
SoC, JH7100 SoC, ssd202d SoC. Etc.
- fwnode gained support for MIPI "DisCo for Imaging"
(https://www.mipi.org/specifications/mipi-disco-imaging)
- as usual, lots of cleanups, fixups and driver improvements.
* tag 'media/v6.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (309 commits)
media: i2c: thp7312: select CONFIG_FW_LOADER
media: i2c: mt9m114: use fsleep() in place of udelay()
media: videobuf2: core: Rename min_buffers_needed field in vb2_queue
media: i2c: thp7312: Store frame interval in subdev state
media: docs: uAPI: Fix documentation of 'which' field for routing ioctls
media: docs: uAPI: Expand error documentation for invalid 'which' value
media: docs: uAPI: Clarify error documentation for invalid 'which' value
media: v4l2-subdev: Store frame interval in subdev state
media: v4l2-subdev: Add which field to struct v4l2_subdev_frame_interval
media: v4l2-subdev: Turn .[gs]_frame_interval into pad operations
media: v4l: subdev: Move out subdev state lock macros outside CONFIG_MEDIA_CONTROLLER
media: s5p-mfc: DPB Count Independent of VIDIOC_REQBUF
media: s5p-mfc: Load firmware for each run in MFCv12.
media: s5p-mfc: Set context for valid case before calling try_run
media: s5p-mfc: Add support for DMABUF for encoder
media: s5p-mfc: Add support for UHD encoding.
media: s5p-mfc: Add support for rate controls in MFCv12
media: s5p-mfc: Add YV12 and I420 multiplanar format support
media: s5p-mfc: Add initial support for MFCv12
media: s5p-mfc: Rename IS_MFCV10 macro
...
Pull documentation update from Jonathan Corbet:
"Another moderately busy cycle for documentation, including:
- The minimum Sphinx requirement has been raised to 2.4.4, following
a warning that was added in 6.2
- Some reworking of the Documentation/process front page to,
hopefully, make it more useful
- Various kernel-doc tweaks to, for example, make it deal properly
with __counted_by annotations
- We have also restored a warning for documentation of nonexistent
structure members that disappeared a while back. That had the
delightful consequence of adding some 600 warnings to the docs
build. A sustained effort by Randy, Vegard, and myself has
addressed almost all of those, bringing the documentation back into
sync with the code. The fixes are going through the appropriate
maintainer trees
- Various improvements to the HTML rendered docs, including automatic
links to Git revisions and a nice new pulldown to make translations
easy to access
- Speaking of translations, more of those for Spanish and Chinese
... plus the usual stream of documentation updates and typo fixes"
* tag 'docs-6.8' of git://git.lwn.net/linux: (57 commits)
MAINTAINERS: use tabs for indent of CONFIDENTIAL COMPUTING THREAT MODEL
A reworked process/index.rst
ring-buffer/Documentation: Add documentation on buffer_percent file
Translated the RISC-V architecture boot documentation.
Docs: remove mentions of fdformat from util-linux
Docs/zh_CN: Fix the meaning of DEBUG to pr_debug()
Documentation: move driver-api/dcdbas to userspace-api/
Documentation: move driver-api/isapnp to userspace-api/
Documentation/core-api : fix typo in workqueue
Documentation/trace: Fixed typos in the ftrace FLAGS section
kernel-doc: handle a void function without producing a warning
scripts/get_abi.pl: ignore some temp files
docs: kernel_abi.py: fix command injection
scripts/get_abi: fix source path leak
CREDITS, MAINTAINERS, docs/process/howto: Update man-pages' maintainer
docs: translations: add translations links when they exist
kernel-doc: Align quick help and the code
MAINTAINERS: add reviewer for Spanish translations
docs: ignore __counted_by attribute in structure definitions
scripts: kernel-doc: Clarify missing struct member description
..
Pull networking updates from Paolo Abeni:
"The most interesting thing is probably the networking structs
reorganization and a significant amount of changes is around
self-tests.
Core & protocols:
- Analyze and reorganize core networking structs (socks, netdev,
netns, mibs) to optimize cacheline consumption and set up build
time warnings to safeguard against future header changes
This improves TCP performances with many concurrent connections up
to 40%
- Add page-pool netlink-based introspection, exposing the memory
usage and recycling stats. This helps indentify bad PP users and
possible leaks
- Refine TCP/DCCP source port selection to no longer favor even
source port at connect() time when IP_LOCAL_PORT_RANGE is set. This
lowers the time taken by connect() for hosts having many active
connections to the same destination
- Refactor the TCP bind conflict code, shrinking related socket
structs
- Refactor TCP SYN-Cookie handling, as a preparation step to allow
arbitrary SYN-Cookie processing via eBPF
- Tune optmem_max for 0-copy usage, increasing the default value to
128KB and namespecifying it
- Allow coalescing for cloned skbs coming from page pools, improving
RX performances with some common configurations
- Reduce extension header parsing overhead at GRO time
- Add bridge MDB bulk deletion support, allowing user-space to
request the deletion of matching entries
- Reorder nftables struct members, to keep data accessed by the
datapath first
- Introduce TC block ports tracking and use. This allows supporting
multicast-like behavior at the TC layer
- Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and
classifiers (RSVP and tcindex)
- More data-race annotations
- Extend the diag interface to dump TCP bound-only sockets
- Conditional notification of events for TC qdisc class and actions
- Support for WPAN dynamic associations with nearby devices, to form
a sub-network using a specific PAN ID
- Implement SMCv2.1 virtual ISM device support
- Add support for Batman-avd mulicast packet type
BPF:
- Tons of verifier improvements:
- BPF register bounds logic and range support along with a large
test suite
- log improvements
- complete precision tracking support for register spills
- track aligned STACK_ZERO cases as imprecise spilled registers.
This improves the verifier "instructions processed" metric from
single digit to 50-60% for some programs
- support for user's global BPF subprogram arguments with few
commonly requested annotations for a better developer
experience
- support tracking of BPF_JNE which helps cases when the compiler
transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the
like
- several fixes
- Add initial TX metadata implementation for AF_XDP with support in
mlx5 and stmmac drivers. Two types of offloads are supported right
now, that is, TX timestamp and TX checksum offload
- Fix kCFI bugs in BPF all forms of indirect calls from BPF into
kernel and from kernel into BPF work with CFI enabled. This allows
BPF to work with CONFIG_FINEIBT=y
- Change BPF verifier logic to validate global subprograms lazily
instead of unconditionally before the main program, so they can be
guarded using BPF CO-RE techniques
- Support uid/gid options when mounting bpffs
- Add a new kfunc which acquires the associated cgroup of a task
within a specific cgroup v1 hierarchy where the latter is
identified by its id
- Extend verifier to allow bpf_refcount_acquire() of a map value
field obtained via direct load which is a use-case needed in
sched_ext
- Add BPF link_info support for uprobe multi link along with bpftool
integration for the latter
- Support for VLAN tag in XDP hints
- Remove deprecated bpfilter kernel leftovers given the project is
developed in user-space (https://github.com/facebook/bpfilter)
Misc:
- Support for parellel TC self-tests execution
- Increase MPTCP self-tests coverage
- Updated the bridge documentation, including several so-far
undocumented features
- Convert all the net self-tests to run in unique netns, to avoid
random failures due to conflict and allow concurrent runs
- Add TCP-AO self-tests
- Add kunit tests for both cfg80211 and mac80211
- Autogenerate Netlink families documentation from YAML spec
- Add yml-gen support for fixed headers and recursive nests, the tool
can now generate user-space code for all genetlink families for
which we have specs
- A bunch of additional module descriptions fixes
- Catch incorrect freeing of pages belonging to a page pool
Driver API:
- Rust abstractions for network PHY drivers; do not cover yet the
full C API, but already allow implementing functional PHY drivers
in rust
- Introduce queue and NAPI support in the netdev Netlink interface,
allowing complete access to the device <> NAPIs <> queues
relationship
- Introduce notifications filtering for devlink to allow control
application scale to thousands of instances
- Improve PHY validation, requesting rate matching information for
each ethtool link mode supported by both the PHY and host
- Add support for ethtool symmetric-xor RSS hash
- ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD
platform
- Expose pin fractional frequency offset value over new DPLL generic
netlink attribute
- Convert older drivers to platform remove callback returning void
- Add support for PHY package MMD read/write
New hardware / drivers:
- Ethernet:
- Octeon CN10K devices
- Broadcom 5760X P7
- Qualcomm SM8550 SoC
- Texas Instrument DP83TG720S PHY
- Bluetooth:
- IMC Networks Bluetooth radio
Removed:
- WiFi:
- libertas 16-bit PCMCIA support
- Atmel at76c50x drivers
- HostAP ISA/PCMCIA style 802.11b driver
- zd1201 802.11b USB dongles
- Orinoco ISA/PCMCIA 802.11b driver
- Aviator/Raytheon driver
- Planet WL3501 driver
- RNDIS USB 802.11b driver
Driver updates:
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- allow one by one port representors creation and removal
- add temperature and clock information reporting
- add get/set for ethtool's header split ringparam
- add again FW logging
- adds support switchdev hardware packet mirroring
- iavf: implement symmetric-xor RSS hash
- igc: add support for concurrent physical and free-running
timers
- i40e: increase the allowable descriptors
- nVidia/Mellanox:
- Preparation for Socket-Direct multi-dev netdev. That will
allow in future releases combining multiple PFs devices
attached to different NUMA nodes under the same netdev
- Broadcom (bnxt):
- TX completion handling improvements
- add basic ntuple filter support
- reduce MSIX vectors usage for MQPRIO offload
- add VXLAN support, USO offload and TX coalesce completion
for P7
- Marvell Octeon EP:
- xmit-more support
- add PF-VF mailbox support and use it for FW notifications
for VFs
- Wangxun (ngbe/txgbe):
- implement ethtool functions to operate pause param, ring
param, coalesce channel number and msglevel
- Netronome/Corigine (nfp):
- add flow-steering support
- support UDP segmentation offload
- Ethernet NICs embedded, slower, virtual:
- Xilinx AXI: remove duplicate DMA code adopting the dma engine
driver
- stmmac: add support for HW-accelerated VLAN stripping
- TI AM654x sw: add mqprio, frame preemption & coalescing
- gve: add support for non-4k page sizes.
- virtio-net: support dynamic coalescing moderation
- nVidia/Mellanox Ethernet datacenter switches:
- allow firmware upgrade without a reboot
- more flexible support for bridge flooding via the compressed
FID flooding mode
- Ethernet embedded switches:
- Microchip:
- fine-tune flow control and speed configurations in KSZ8xxx
- KSZ88X3: enable setting rmii reference
- Renesas:
- add jumbo frames support
- Marvell:
- 88E6xxx: add "eth-mac" and "rmon" stats support
- Ethernet PHYs:
- aquantia: add firmware load support
- at803x: refactor the driver to simplify adding support for more
chip variants
- NXP C45 TJA11xx: Add MACsec offload support
- Wifi:
- MediaTek (mt76):
- NVMEM EEPROM improvements
- mt7996 Extremely High Throughput (EHT) improvements
- mt7996 Wireless Ethernet Dispatcher (WED) support
- mt7996 36-bit DMA support
- Qualcomm (ath12k):
- support for a single MSI vector
- WCN7850: support AP mode
- Intel (iwlwifi):
- new debugfs file fw_dbg_clear
- allow concurrent P2P operation on DFS channels
- Bluetooth:
- QCA2066: support HFP offload
- ISO: more broadcast-related improvements
- NXP: better recovery in case receiver/transmitter get out of sync"
* tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1714 commits)
lan78xx: remove redundant statement in lan78xx_get_eee
lan743x: remove redundant statement in lan743x_ethtool_get_eee
bnxt_en: Fix RCU locking for ntuple filters in bnxt_rx_flow_steer()
bnxt_en: Fix RCU locking for ntuple filters in bnxt_srxclsrldel()
bnxt_en: Remove unneeded variable in bnxt_hwrm_clear_vnic_filter()
tcp: Revert no longer abort SYN_SENT when receiving some ICMP
Revert "mlx5 updates 2023-12-20"
Revert "net: stmmac: Enable Per DMA Channel interrupt"
ipvlan: Remove usage of the deprecated ida_simple_xx() API
ipvlan: Fix a typo in a comment
net/sched: Remove ipt action tests
net: stmmac: Use interrupt mode INTM=1 for per channel irq
net: stmmac: Add support for TX/RX channel interrupt
net: stmmac: Make MSI interrupt routine generic
dt-bindings: net: snps,dwmac: per channel irq
net: phy: at803x: make read_status more generic
net: phy: at803x: add support for cdt cross short test for qca808x
net: phy: at803x: refactor qca808x cable test get status function
net: phy: at803x: generalize cdt fault length function
net: ethernet: cortina: Drop TSO support
...
Fix two typos in the admin-guide:
- a missing e in "reference_perf" in cppc_sysfs.rst.
- the amd_pstate sysfs path uses a dash instead of an underscore.
Signed-off-by: Erwan Velu <e.velu@criteo.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull x86 platform driver updates from Hans de Goede:
- Intel PMC / PMT / TPMI / uncore-freq / vsec improvements and new
platform support
- AMD PMC / PMF improvements and new platform support
- AMD ACPI based Wifi band RFI mitigation feature (WBRF)
- WMI bus driver cleanups and improvements (Armin Wolf)
- acer-wmi Predator PHN16-71 support
- New Silicom network appliance EC LEDs / GPIOs driver
* tag 'platform-drivers-x86-v6.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86: (96 commits)
platform/x86/amd/pmc: Modify SMU message port for latest AMD platform
platform/x86/amd/pmc: Add 1Ah family series to STB support list
platform/x86/amd/pmc: Add idlemask support for 1Ah family
platform/x86/amd/pmc: call amd_pmc_get_ip_info() during driver probe
platform/x86/amd/pmc: Add VPE information for AMDI000A platform
platform/x86/amd/pmc: Send OS_HINT command for AMDI000A platform
platform/x86/amd/pmf: Return a status code only as a constant in two functions
platform/x86/amd/pmf: Return directly after a failed apmf_if_call() in apmf_sbios_heartbeat_notify()
platform/x86: wmi: linux/wmi.h: fix Excess kernel-doc description warning
platform/x86/intel/pmc: Add missing extern
platform/x86/intel/pmc/lnl: Add GBE LTR ignore during suspend
platform/x86/intel/pmc/arl: Add GBE LTR ignore during suspend
platform/x86: intel-uncore-freq: Add additional client processors
platform/x86: Remove "X86 PLATFORM DRIVERS - ARCH" from MAINTAINERS
platform/x86: hp-bioscfg: Removed needless asm-generic
platform/x86/intel/pmc: Add Lunar Lake M support to intel_pmc_core driver
platform/x86/intel/pmc: Add Arrow Lake S support to intel_pmc_core driver
platform/x86/intel/pmc: Add ssram_init flag in PMC discovery in Meteor Lake
platform/x86/intel/pmc: Move common code to core.c
platform/x86/intel/pmc: Add PSON residency counter for Alder Lake
...
Pull regulator updates from Mark Brown:
"The main updates for this release are around monitoring of regulators,
largely for error handling purposes. We allow the stream of regulator
events to be seen by userspace as netlink events and allow system
integrators to describe individual regulators as system critical with
information on how long the system is expected to last on error. The
system level error handling is very much about best effort problem
mitigation rather than providing something fully robust, the initial
drive was to provide a mechanism for trying to avoid initiating any
new writes to flash once we notice the power going out.
Otherwise it's very quiet, mainly several new Qualcomm devices.
- Support for marking regulators as system critical and providing
information on how long the system might last with those regulators
in a failure state, hooked into the existing critical shutdown
error handling.
- Optional support for generating netlink events for events, there
are use cases for system monitoring UIs and error handling.
- A command line option to leave unused controllable regulators
enabled, useful for debugging. We already only disable regulators
we were explicitly given permission to control.
- Support for Quacomm MP5496, PM8010 and PM8937"
* tag 'regulator-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (31 commits)
regulator: event: Ensure atomicity for sequence number
uapi: regulator: Fix typo
regulator: Reuse LINEAR_RANGE() in REGULATOR_LINEAR_RANGE()
dt-bindings: regulator: qcom,usb-vbus-regulator: clean up example
regulator: qcom_smd: Add LDO5 MP5496 regulator
regulator: qcom-rpmh: add support for pm8010 regulators
regulator: dt-bindings: qcom,rpmh: add compatible for pm8010
regulator: qcom-rpmh: extend to support multiple linear voltage ranges
regulator: wm8350: Convert to platform remove callback returning void
regulator: virtual: Convert to platform remove callback returning void
regulator: userspace-consumer: Convert to platform remove callback returning void
regulator: uniphier: Convert to platform remove callback returning void
regulator: stm32-vrefbuf: Convert to platform remove callback returning void
regulator: db8500-prcmu: Convert to platform remove callback returning void
regulator: bd9571mwv: Convert to platform remove callback returning void
regulator: arizona-ldo1: Convert to platform remove callback returning void
regulator: event: Add regulator netlink event support
regulator: event: Add regulator netlink event support
regulator: stpmic1: Fix kernel-doc notation warnings
regulator: palmas: remove redundant initialization of pointer pdata
...
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Peng Zhang has done some mapletree maintainance work in the series
'maple_tree: add mt_free_one() and mt_attr() helpers'
'Some cleanups of maple tree'
- In the series 'mm: use memmap_on_memory semantics for dax/kmem'
Vishal Verma has altered the interworking between memory-hotplug
and dax/kmem so that newly added 'device memory' can more easily
have its memmap placed within that newly added memory.
- Matthew Wilcox continues folio-related work (including a few fixes)
in the patch series
'Add folio_zero_tail() and folio_fill_tail()'
'Make folio_start_writeback return void'
'Fix fault handler's handling of poisoned tail pages'
'Convert aops->error_remove_page to ->error_remove_folio'
'Finish two folio conversions'
'More swap folio conversions'
- Kefeng Wang has also contributed folio-related work in the series
'mm: cleanup and use more folio in page fault'
- Jim Cromie has improved the kmemleak reporting output in the series
'tweak kmemleak report format'.
- In the series 'stackdepot: allow evicting stack traces' Andrey
Konovalov to permits clients (in this case KASAN) to cause eviction
of no longer needed stack traces.
- Charan Teja Kalla has fixed some accounting issues in the page
allocator's atomic reserve calculations in the series 'mm:
page_alloc: fixes for high atomic reserve caluculations'.
- Dmitry Rokosov has added to the samples/ dorectory some sample code
for a userspace memcg event listener application. See the series
'samples: introduce cgroup events listeners'.
- Some mapletree maintanance work from Liam Howlett in the series
'maple_tree: iterator state changes'.
- Nhat Pham has improved zswap's approach to writeback in the series
'workload-specific and memory pressure-driven zswap writeback'.
- DAMON/DAMOS feature and maintenance work from SeongJae Park in the
series
'mm/damon: let users feed and tame/auto-tune DAMOS'
'selftests/damon: add Python-written DAMON functionality tests'
'mm/damon: misc updates for 6.8'
- Yosry Ahmed has improved memcg's stats flushing in the series 'mm:
memcg: subtree stats flushing and thresholds'.
- In the series 'Multi-size THP for anonymous memory' Ryan Roberts
has added a runtime opt-in feature to transparent hugepages which
improves performance by allocating larger chunks of memory during
anonymous page faults.
- Matthew Wilcox has also contributed some cleanup and maintenance
work against eh buffer_head code int he series 'More buffer_head
cleanups'.
- Suren Baghdasaryan has done work on Andrea Arcangeli's series
'userfaultfd move option'. UFFDIO_MOVE permits userspace heap
compaction algorithms to move userspace's pages around rather than
UFFDIO_COPY'a alloc/copy/free.
- Stefan Roesch has developed a 'KSM Advisor', in the series 'mm/ksm:
Add ksm advisor'. This is a governor which tunes KSM's scanning
aggressiveness in response to userspace's current needs.
- Chengming Zhou has optimized zswap's temporary working memory use
in the series 'mm/zswap: dstmem reuse optimizations and cleanups'.
- Matthew Wilcox has performed some maintenance work on the writeback
code, both code and within filesystems. The series is 'Clean up the
writeback paths'.
- Andrey Konovalov has optimized KASAN's handling of alloc and free
stack traces for secondary-level allocators, in the series 'kasan:
save mempool stack traces'.
- Andrey also performed some KASAN maintenance work in the series
'kasan: assorted clean-ups'.
- David Hildenbrand has gone to town on the rmap code. Cleanups, more
pte batching, folio conversions and more. See the series 'mm/rmap:
interface overhaul'.
- Kinsey Ho has contributed some maintenance work on the MGLRU code
in the series 'mm/mglru: Kconfig cleanup'.
- Matthew Wilcox has contributed lruvec page accounting code cleanups
in the series 'Remove some lruvec page accounting functions'"
* tag 'mm-stable-2024-01-08-15-31' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (361 commits)
mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDER
mm, treewide: introduce NR_PAGE_ORDERS
selftests/mm: add separate UFFDIO_MOVE test for PMD splitting
selftests/mm: skip test if application doesn't has root privileges
selftests/mm: conform test to TAP format output
selftests: mm: hugepage-mmap: conform to TAP format output
selftests/mm: gup_test: conform test to TAP format output
mm/selftests: hugepage-mremap: conform test to TAP format output
mm/vmstat: move pgdemote_* out of CONFIG_NUMA_BALANCING
mm: zsmalloc: return -ENOSPC rather than -EINVAL in zs_malloc while size is too large
mm/memcontrol: remove __mod_lruvec_page_state()
mm/khugepaged: use a folio more in collapse_file()
slub: use a folio in __kmalloc_large_node
slub: use folio APIs in free_large_kmalloc()
slub: use alloc_pages_node() in alloc_slab_page()
mm: remove inc/dec lruvec page state functions
mm: ratelimit stat flush from workingset shrinker
kasan: stop leaking stack trace handles
mm/mglru: remove CONFIG_TRANSPARENT_HUGEPAGE
mm/mglru: add dummy pmd_dirty()
...
Pull cgroup updates from Tejun Heo:
- Yafang Shao added task_get_cgroup1() helper to enable a similar BPF
helper so that BPF progs can be more useful on cgroup1 hierarchies.
While cgroup1 is mostly in maintenance mode, this addition is very
small while having an outsized usefulness for users who are still on
cgroup1. Yafang also optimized root cgroup list access by making it
RCU protected in the process.
- Waiman Long optimized rstat operation leading to substantially lower
and more consistent lock hold time while flushing the hierarchical
statistics. As the lock can be acquired briefly in various hot paths,
this reduction has cascading benefits.
- Waiman also improved the quality of isolation for cpuset's isolated
partitions. CPUs which are allocated to isolated partitions are now
excluded from running unbound work items and cpu_is_isolated() test
which is used by vmstat and memcg to reduce interference now includes
cpuset isolated CPUs. While it isn't there yet, the hope is
eventually reaching parity with the isolation level provided by the
`isolcpus` boot param but in a dynamic manner.
* tag 'cgroup-for-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: Move rcu_head up near the top of cgroup_root
cgroup/cpuset: Include isolated cpuset CPUs in cpu_is_isolated() check
cgroup: Avoid false cacheline sharing of read mostly rstat_cpu
cgroup/rstat: Optimize cgroup_rstat_updated_list()
cgroup: Fix documentation for cpu.idle
cgroup/cpuset: Expose cpuset.cpus.isolated
workqueue: Move workqueue_set_unbound_cpumask() and its helpers inside CONFIG_SYSFS
cgroup/rstat: Reduce cpu_lock hold time in cgroup_rstat_flush_locked()
cgroup/cpuset: Take isolated CPUs out of workqueue unbound cpumask
cgroup/cpuset: Keep track of CPUs in isolated partitions
selftests/cgroup: Minor code cleanup and reorganization of test_cpuset_prs.sh
workqueue: Add workqueue_unbound_exclude_cpumask() to exclude CPUs from wq_unbound_cpumask
selftests: cgroup: Fixes a typo in a comment
cgroup: Add a new helper for cgroup1 hierarchy
cgroup: Add annotation for holding namespace_sem in current_cgns_cgroup_from_root()
cgroup: Eliminate the need for cgroup_mutex in proc_cgroup_show()
cgroup: Make operations on the cgroup root_list RCU safe
cgroup: Remove unnecessary list_empty()
Add the files and functions needed to support paravirt time on
RISC-V. Also include the common code needed for the first
application of pv-time, which is steal-time. In the next
patches we'll complete the functions to fully enable steal-time
support.
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Anup Patel <anup@brainfault.org>
During our experiment with zswap, we sometimes observe swap IOs due to
occasional zswap store failures and writebacks-to-swap. These swapping
IOs prevent many users who cannot tolerate swapping from adopting zswap to
save memory and improve performance where possible.
This patch adds the option to disable this behavior entirely: do not
writeback to backing swapping device when a zswap store attempt fail, and
do not write pages in the zswap pool back to the backing swap device (both
when the pool is full, and when the new zswap shrinker is called).
This new behavior can be opted-in/out on a per-cgroup basis via a new
cgroup file. By default, writebacks to swap device is enabled, which is
the previous behavior. Initially, writeback is enabled for the root
cgroup, and a newly created cgroup will inherit the current setting of its
parent.
Note that this is subtly different from setting memory.swap.max to 0, as
it still allows for pages to be stored in the zswap pool (which itself
consumes swap space in its current form).
This patch should be applied on top of the zswap shrinker series:
https://lore.kernel.org/linux-mm/20231130194023.4102148-1-nphamcs@gmail.com/
as it also disables the zswap shrinker, a major source of zswap
writebacks.
For the most part, this feature is motivated by internal parties who
have already established their opinions regarding swapping - the
workloads that are highly sensitive to IO, and especially those who are
using servers with really slow disk performance (for instance, massive
but slow HDDs). For these folks, it's impossible to convince them to
even entertain zswap if swapping also comes as a packaged deal.
Writeback disabling is quite a useful feature in these situations - on
a mixed workloads deployment, they can disable writeback for the more
IO-sensitive workloads, and enable writeback for other background
workloads.
For instance, on a server with HDD, I allocate memories and populate
them with random values (so that zswap store will always fail), and
specify memory.high low enough to trigger reclaim. The time it takes
to allocate the memories and just read through it a couple of times
(doing silly things like computing the values' average etc.):
zswap.writeback disabled:
real 0m30.537s
user 0m23.687s
sys 0m6.637s
0 pages swapped in
0 pages swapped out
zswap.writeback enabled:
real 0m45.061s
user 0m24.310s
sys 0m8.892s
712686 pages swapped in
461093 pages swapped out
(the last two lines are from vmstat -s).
[nphamcs@gmail.com: add a comment about recurring zswap store failures leading to reclaim inefficiency]
Link: https://lkml.kernel.org/r/20231221005725.3446672-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20231207192406.3809579-1-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Yosry Ahmed <yosryahmed@google.com>
Acked-by: Chris Li <chrisl@kernel.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: David Heidelberg <david@ixit.cz>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Implement the uABI of UFFDIO_MOVE ioctl.
UFFDIO_COPY performs ~20% better than UFFDIO_MOVE when the application
needs pages to be allocated [1]. However, with UFFDIO_MOVE, if pages are
available (in userspace) for recycling, as is usually the case in heap
compaction algorithms, then we can avoid the page allocation and memcpy
(done by UFFDIO_COPY). Also, since the pages are recycled in the
userspace, we avoid the need to release (via madvise) the pages back to
the kernel [2].
We see over 40% reduction (on a Google pixel 6 device) in the compacting
thread's completion time by using UFFDIO_MOVE vs. UFFDIO_COPY. This was
measured using a benchmark that emulates a heap compaction implementation
using userfaultfd (to allow concurrent accesses by application threads).
More details of the usecase are explained in [2]. Furthermore,
UFFDIO_MOVE enables moving swapped-out pages without touching them within
the same vma. Today, it can only be done by mremap, however it forces
splitting the vma.
[1] https://lore.kernel.org/all/1425575884-2574-1-git-send-email-aarcange@redhat.com/
[2] https://lore.kernel.org/linux-mm/CA+EESO4uO84SSnBhArH4HvLNhaUQ5nZKNKXqxRCyjniNVjp0Aw@mail.gmail.com/
Update for the ioctl_userfaultfd(2) manpage:
UFFDIO_MOVE
(Since Linux xxx) Move a continuous memory chunk into the
userfault registered range and optionally wake up the blocked
thread. The source and destination addresses and the number of
bytes to move are specified by the src, dst, and len fields of
the uffdio_move structure pointed to by argp:
struct uffdio_move {
__u64 dst; /* Destination of move */
__u64 src; /* Source of move */
__u64 len; /* Number of bytes to move */
__u64 mode; /* Flags controlling behavior of move */
__s64 move; /* Number of bytes moved, or negated error */
};
The following value may be bitwise ORed in mode to change the
behavior of the UFFDIO_MOVE operation:
UFFDIO_MOVE_MODE_DONTWAKE
Do not wake up the thread that waits for page-fault
resolution
UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES
Allow holes in the source virtual range that is being moved.
When not specified, the holes will result in ENOENT error.
When specified, the holes will be accounted as successfully
moved memory. This is mostly useful to move hugepage aligned
virtual regions without knowing if there are transparent
hugepages in the regions or not, but preventing the risk of
having to split the hugepage during the operation.
The move field is used by the kernel to return the number of
bytes that was actually moved, or an error (a negated errno-
style value). If the value returned in move doesn't match the
value that was specified in len, the operation fails with the
error EAGAIN. The move field is output-only; it is not read by
the UFFDIO_MOVE operation.
The operation may fail for various reasons. Usually, remapping of
pages that are not exclusive to the given process fail; once KSM
might deduplicate pages or fork() COW-shares pages during fork()
with child processes, they are no longer exclusive. Further, the
kernel might only perform lightweight checks for detecting whether
the pages are exclusive, and return -EBUSY in case that check fails.
To make the operation more likely to succeed, KSM should be
disabled, fork() should be avoided or MADV_DONTFORK should be
configured for the source VMA before fork().
This ioctl(2) operation returns 0 on success. In this case, the
entire area was moved. On error, -1 is returned and errno is
set to indicate the error. Possible errors include:
EAGAIN The number of bytes moved (i.e., the value returned in
the move field) does not equal the value that was
specified in the len field.
EINVAL Either dst or len was not a multiple of the system page
size, or the range specified by src and len or dst and len
was invalid.
EINVAL An invalid bit was specified in the mode field.
ENOENT
The source virtual memory range has unmapped holes and
UFFDIO_MOVE_MODE_ALLOW_SRC_HOLES is not set.
EEXIST
The destination virtual memory range is fully or partially
mapped.
EBUSY
The pages in the source virtual memory range are either
pinned or not exclusive to the process. The kernel might
only perform lightweight checks for detecting whether the
pages are exclusive. To make the operation more likely to
succeed, KSM should be disabled, fork() should be avoided
or MADV_DONTFORK should be configured for the source virtual
memory area before fork().
ENOMEM Allocating memory needed for the operation failed.
ESRCH
The target process has exited at the time of a UFFDIO_MOVE
operation.
Link: https://lkml.kernel.org/r/20231206103702.3873743-3-surenb@google.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Nicolas Geoffray <ngeoffray@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: ZhangPeng <zhangpeng362@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are eight command inputs for 'state' DAMON sysfs file, and those are
verbosely explained in multiple paragraphs. It is not easy to find
explanation of specific command, and getting whole picture of supported
commands. Replace the paragraphs with a list.
Link: https://lkml.kernel.org/r/20231213190338.54146-7-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
'Sysfs Files Hierarchy' section of DAMON usage document shows whole
picture of the interface. Then sections for detailed explanation of the
files follow. Due to the amount of the files, navigating between the
whole picture and the section for specific files sometimes require no
subtle amount of scrolling. Add links from the whole picture to the
dedicated sections for making the navigation easier.
Link: https://lkml.kernel.org/r/20231213190338.54146-6-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In preparation for adding support for anonymous multi-size THP, introduce
new sysfs structure that will be used to control the new behaviours. A
new directory is added under transparent_hugepage for each supported THP
size, and contains an `enabled` file, which can be set to "inherit" (to
inherit the global setting), "always", "madvise" or "never". For now, the
kernel still only supports PMD-sized anonymous THP, so only 1 directory is
populated.
The first half of the change converts transhuge_vma_suitable() and
hugepage_vma_check() so that they take a bitfield of orders for which the
user wants to determine support, and the functions filter out all the
orders that can't be supported, given the current sysfs configuration and
the VMA dimensions. The resulting functions are renamed to
thp_vma_suitable_orders() and thp_vma_allowable_orders() respectively.
Convenience functions that take a single, unencoded order and return a
boolean are also defined as thp_vma_suitable_order() and
thp_vma_allowable_order().
The second half of the change implements the new sysfs interface. It has
been done so that each supported THP size has a `struct thpsize`, which
describes the relevant metadata and is itself a kobject. This is pretty
minimal for now, but should make it easy to add new per-thpsize files to
the interface if needed in future (e.g. per-size defrag). Rather than
keep the `enabled` state directly in the struct thpsize, I've elected to
directly encode it into huge_anon_orders_[always|madvise|inherit]
bitfields since this reduces the amount of work required in
thp_vma_allowable_orders() which is called for every page fault.
See Documentation/admin-guide/mm/transhuge.rst, as modified by this
commit, for details of how the new sysfs interface works.
[ryan.roberts@arm.com: fix build warning when CONFIG_SYSFS is disabled]
Link: https://lkml.kernel.org/r/20231211125320.3997543-1-ryan.roberts@arm.com
Link: https://lkml.kernel.org/r/20231207161211.2374093-4-ryan.roberts@arm.com
Signed-off-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Barry Song <v-songbaohua@oppo.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Itaru Kitayama <itaru.kitayama@gmail.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yin Fengwei <fengwei.yin@intel.com>
Cc: Yu Zhao <yuzhao@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
PMF driver based on the output actions from the TA can request to update
the system states like entering s0i3, lock screen etc. by generating
an uevent. Based on the udev rules set in the userspace the event id
matching the uevent shall get updated accordingly using the systemctl.
Sample udev rules under Documentation/admin-guide/pmf.rst.
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20231212014705.2017474-9-Shyam-sundar.S-k@amd.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
When the kernel command line option "retain_initrd" is set, we do not
free the initrd memory. However, we also don't expose it to anyone for
consumption. That leaves us in a weird situation where the only user of
this feature is ppc64 and arm64 specific kexec tooling.
To make it more generally useful, this patch adds a kobject to the
firmware object that contains the initrd context when "retain_initrd"
is set. That way, we can access the initrd any time after boot from
user space and for example hand it into kexec as --initrd parameter
if we want to reboot the same initrd. Or inspect it directly locally.
With this patch applied, there is a new /sys/firmware/initrd file when
the kernel was booted with an initrd and "retain_initrd" command line
option is set.
Signed-off-by: Alexander Graf <graf@amazon.com>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20231207235654.16622-1-graf@amazon.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For many years, /proc/sys/net/core/optmem_max default value
on a 64bit kernel has been 20 KB.
Regular usage of TCP tx zerocopy needs a bit more.
Google has used 128KB as the default value for 7 years without
any problem.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, we only shrink the zswap pool when the user-defined limit is
hit. This means that if we set the limit too high, cold data that are
unlikely to be used again will reside in the pool, wasting precious
memory. It is hard to predict how much zswap space will be needed ahead
of time, as this depends on the workload (specifically, on factors such as
memory access patterns and compressibility of the memory pages).
This patch implements a memcg- and NUMA-aware shrinker for zswap, that is
initiated when there is memory pressure. The shrinker does not have any
parameter that must be tuned by the user, and can be opted in or out on a
per-memcg basis.
Furthermore, to make it more robust for many workloads and prevent
overshrinking (i.e evicting warm pages that might be refaulted into
memory), we build in the following heuristics:
* Estimate the number of warm pages residing in zswap, and attempt to
protect this region of the zswap LRU.
* Scale the number of freeable objects by an estimate of the memory
saving factor. The better zswap compresses the data, the fewer pages
we will evict to swap (as we will otherwise incur IO for relatively
small memory saving).
* During reclaim, if the shrinker encounters a page that is also being
brought into memory, the shrinker will cautiously terminate its
shrinking action, as this is a sign that it is touching the warmer
region of the zswap LRU.
As a proof of concept, we ran the following synthetic benchmark: build the
linux kernel in a memory-limited cgroup, and allocate some cold data in
tmpfs to see if the shrinker could write them out and improved the overall
performance. Depending on the amount of cold data generated, we observe
from 14% to 35% reduction in kernel CPU time used in the kernel builds.
[nphamcs@gmail.com: check shrinker enablement early, use less costly stat flushing]
Link: https://lkml.kernel.org/r/20231206194456.3234203-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20231130194023.4102148-7-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Although the RCU CPU stall notifiers can be useful for dumping state when
tracking down delicate forward-progress bugs where NUMA effects cause
cache lines to be delivered to a given CPU regularly, but always in a
state that prevents that CPU from making forward progress. These bugs can
be detected by the RCU CPU stall-warning mechanism, but in some cases,
the stall-warnings printk()s disrupt the forward-progress bug before
any useful state can be obtained.
Unfortunately, the notifier mechanism added by commit 5b404fdaba ("rcu:
Add RCU CPU stall notifier") can make matters worse if used at all
carelessly. For example, if the stall warning was caused by a lock not
being released, then any attempt to acquire that lock in the notifier
will hang. This will prevent not only the notifier from producing any
useful output, but it will also prevent the stall-warning message from
ever appearing.
This commit therefore hides this new RCU CPU stall notifier
mechanism under a new RCU_CPU_STALL_NOTIFIER Kconfig option that
depends on both DEBUG_KERNEL and RCU_EXPERT. In addition, the
rcupdate.rcu_cpu_stall_notifiers=1 kernel boot parameter must also
be specified. The RCU_CPU_STALL_NOTIFIER Kconfig option's help text
contains a warning and explains the dangers of careless use, recommending
lockless notifier code. In addition, a WARN() is triggered each time
that an attempt is made to register a stall-warning notifier in kernels
built with CONFIG_RCU_CPU_STALL_NOTIFIER=y.
This combination of measures will keep use of this mechanism confined to
debug kernels and away from routine deployments.
[ paulmck: Apply Dan Carpenter feedback. ]
Fixes: 5b404fdaba ("rcu: Add RCU CPU stall notifier")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>
The PAGEMAP_SCAN ioctl returns information regarding page table entries.
It is more efficient compared to reading pagemap files. CRIU can start to
utilize this ioctl, but it needs info about soft-dirty bits to track
memory changes.
We are aware of a new method for tracking memory changes implemented in
the PAGEMAP_SCAN ioctl. For CRIU, the primary advantage of this method is
its usability by unprivileged users. However, it is not feasible to
transparently replace the soft-dirty tracker with the new one. The main
problem here is userfault descriptors that have to be preserved between
pre-dump iterations. It means criu continues supporting the soft-dirty
method to avoid breakage for current users. The new method will be
implemented as a separate feature.
[avagin@google.com: update tools/include/uapi/linux/fs.h]
Link: https://lkml.kernel.org/r/20231107164139.576046-1-avagin@google.com
Link: https://lkml.kernel.org/r/20231106220959.296568-1-avagin@google.com
Signed-off-by: Andrei Vagin <avagin@google.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Two problems:
- cpu.idle cgroups show up with 0 weight, correct the
documentation to indicate this.
- cpu.idle has no entry describing it.
Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The root-only cpuset.cpus.isolated control file shows the current set
of isolated CPUs in isolated partitions. This control file is currently
exposed only with the cgroup_debug boot command line option which also
adds the ".__DEBUG__." prefix. This is actually a useful control file if
users want to find out which CPUs are currently in an isolated state by
the cpuset controller. Remove CFTYPE_DEBUG flag for this control file and
make it available by default without any prefix.
The test_cpuset_prs.sh test script and the cgroup-v2.rst documentation
file are also updated accordingly. Minor code change is also made in
test_cpuset_prs.sh to avoid false test failure when running on debug
kernel.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This way we can do:
`echo _reisub > /proc/sysrq-trigger`
Instead of:
`for i in r e i s u b; do echo "$i" > /proc/sysrq-trigger; done;`
This can be very useful when trying to execute sysrq combo remotely
or from userspace. When sending keys in multiple separate writes,
userspace (eg. bash or ssh) can be killed before whole combo is completed.
Therefore putting all keys in single write is more robust approach.
Signed-off-by: Tomas Mudrunka <tomas.mudrunka@gmail.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20231120111451.527952-1-tomas.mudrunka@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch introduces a new USB quirk,
USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT, which modifies the timeout value
for the SET_ADDRESS request. The standard timeout for USB request/command
is 5000 ms, as recommended in the USB 3.2 specification (section 9.2.6.1).
However, certain scenarios, such as connecting devices through an APTIV
hub, can lead to timeout errors when the device enumerates as full speed
initially and later switches to high speed during chirp negotiation.
In such cases, USB analyzer logs reveal that the bus suspends for
5 seconds due to incorrect chirp parsing and resumes only after two
consecutive timeout errors trigger a hub driver reset.
Packet(54) Dir(?) Full Speed J(997.100 us) Idle( 2.850 us)
_______| Time Stamp(28 . 105 910 682)
_______|_____________________________________________________________Ch0
Packet(55) Dir(?) Full Speed J(997.118 us) Idle( 2.850 us)
_______| Time Stamp(28 . 106 910 632)
_______|_____________________________________________________________Ch0
Packet(56) Dir(?) Full Speed J(399.650 us) Idle(222.582 us)
_______| Time Stamp(28 . 107 910 600)
_______|_____________________________________________________________Ch0
Packet(57) Dir Chirp J( 23.955 ms) Idle(115.169 ms)
_______| Time Stamp(28 . 108 532 832)
_______|_____________________________________________________________Ch0
Packet(58) Dir(?) Full Speed J (Suspend)( 5.347 sec) Idle( 5.366 us)
_______| Time Stamp(28 . 247 657 600)
_______|_____________________________________________________________Ch0
This 5-second delay in device enumeration is undesirable, particularly
in automotive applications where quick enumeration is crucial
(ideally within 3 seconds).
The newly introduced quirks provide the flexibility to align with a
3-second time limit, as required in specific contexts like automotive
applications.
By reducing the SET_ADDRESS request timeout to 500 ms, the
system can respond more swiftly to errors, initiate rapid recovery, and
ensure efficient device enumeration. This change is vital for scenarios
where rapid smartphone enumeration and screen projection are essential.
To use the quirk, please write "vendor_id:product_id:p" to
/sys/bus/usb/drivers/hub/module/parameter/quirks
For example,
echo "0x2c48:0x0132:p" > /sys/bus/usb/drivers/hub/module/parameters/quirks"
Signed-off-by: Hardik Gajjar <hgajjar@de.adit-jv.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20231027152029.104363-2-hgajjar@de.adit-jv.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Vegard Nossum writes:
This patch series replaces some instances of 'class:: toc-title' with
toctree's :caption: attribute, see the last patch in the series for some
more rationale/explanation.
Add starfive_camss.rst file that documents the Starfive Camera
Subsystem driver which is used for handing image sensor data.
Signed-off-by: Jack Zhu <jack.zhu@starfivetech.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
This may be useful for debugging and develompent purposes, when there are
drivers that depend on regulators to be enabled but do not request them.
It is inspired from the clk_ignore_unused and pd_ignore_unused parameters,
that are used to keep firmware-enabled clocks and power domains on even if
these are not used by drivers.
The parameter is not expected to be used in normal cases and should not be
needed on a platform with proper driver support.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Brian Masney <bmasney@redhat.com>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20231107190926.1185326-1-javierm@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>
To make CPUs in isolated cpuset partition closer in isolation to
the boot time isolated CPUs specified in the "isolcpus" boot command
line option, we need to take those CPUs out of the workqueue unbound
cpumask so that work functions from the unbound workqueues won't run
on those CPUs. Otherwise, they will interfere the user tasks running
on those isolated CPUs.
With the introduction of the workqueue_unbound_exclude_cpumask() helper
function in an earlier commit, those isolated CPUs can now be taken
out from the workqueue unbound cpumask.
This patch also updates cgroup-v2.rst to mention that isolated
CPUs will be excluded from unbound workqueue cpumask as well as
updating test_cpuset_prs.sh to verify the correctness of the new
*cpuset.cpus.isolated file, if available via cgroup_debug option.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull iommu updates from Joerg Roedel:
"Core changes:
- Make default-domains mandatory for all IOMMU drivers
- Remove group refcounting
- Add generic_single_device_group() helper and consolidate drivers
- Cleanup map/unmap ops
- Scaling improvements for the IOVA rcache depot
- Convert dart & iommufd to the new domain_alloc_paging()
ARM-SMMU:
- Device-tree binding update:
- Add qcom,sm7150-smmu-v2 for Adreno on SM7150 SoC
- SMMUv2:
- Support for Qualcomm SDM670 (MDSS) and SM7150 SoCs
- SMMUv3:
- Large refactoring of the context descriptor code to move the CD
table into the master, paving the way for '->set_dev_pasid()'
support on non-SVA domains
- Minor cleanups to the SVA code
Intel VT-d:
- Enable debugfs to dump domain attached to a pasid
- Remove an unnecessary inline function
AMD IOMMU:
- Initial patches for SVA support (not complete yet)
S390 IOMMU:
- DMA-API conversion and optimized IOTLB flushing
And some smaller fixes and improvements"
* tag 'iommu-updates-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (102 commits)
iommu/dart: Remove the force_bypass variable
iommu/dart: Call apple_dart_finalize_domain() as part of alloc_paging()
iommu/dart: Convert to domain_alloc_paging()
iommu/dart: Move the blocked domain support to a global static
iommu/dart: Use static global identity domains
iommufd: Convert to alloc_domain_paging()
iommu/vt-d: Use ops->blocked_domain
iommu/vt-d: Update the definition of the blocking domain
iommu: Move IOMMU_DOMAIN_BLOCKED global statics to ops->blocked_domain
Revert "iommu/vt-d: Remove unused function"
iommu/amd: Remove DMA_FQ type from domain allocation path
iommu: change iommu_map_sgtable to return signed values
iommu/virtio: Add __counted_by for struct viommu_request and use struct_size()
iommu/vt-d: debugfs: Support dumping a specified page table
iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid}
iommu/vt-d: debugfs: Dump entry pointing to huge page
iommu/vt-d: Remove unused function
iommu/arm-smmu-v3-sva: Remove bond refcount
iommu/arm-smmu-v3-sva: Remove unused iommu_sva handle
iommu/arm-smmu-v3: Rename cdcfg to cd_table
...
