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2024-01-23docs: admin-guide: remove obsolete advice related to SLAB allocatorGravatar Lukas Bulwahn 1-10/+6
Commit 1db9d06aaa55 ("mm/slab: remove CONFIG_SLAB from all Kconfig and Makefile") removes the config SLAB and makes the SLUB allocator the only default allocator in the kernel. Hence, the advice on reducing OS jitter due to kworker kernel threads to build with CONFIG_SLUB instead of CONFIG_SLAB is obsolete. Remove the obsolete advice to build with SLUB instead of SLAB. Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231130095515.21586-1-lukas.bulwahn@gmail.com
2024-01-23doc: admin-guide/kernel-parameters: remove useless commentGravatar Vegard Nossum 1-5/+0
This comment about DRM drivers has been there since the first git commit. It simply doesn't belong in kernel-parameters; remove it. Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240111085220.3693059-1-vegard.nossum@oracle.com
2024-01-20Merge tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6Gravatar Linus Torvalds 2-24/+28
Pull smb client updates from Steve French: "Various smb client fixes, including multichannel and for SMB3.1.1 POSIX extensions: - debugging improvement (display start time for stats) - two reparse point handling fixes - various multichannel improvements and fixes - SMB3.1.1 POSIX extensions open/create parsing fix - retry (reconnect) improvement including new retrans mount parm, and handling of two additional return codes that need to be retried on - two minor cleanup patches and another to remove duplicate query info code - two documentation cleanup, and one reviewer email correction" * tag 'v6.8-rc-part2-smb-client' of git://git.samba.org/sfrench/cifs-2.6: cifs: update iface_last_update on each query-and-update cifs: handle servers that still advertise multichannel after disabling cifs: new mount option called retrans cifs: reschedule periodic query for server interfaces smb: client: don't clobber ->i_rdev from cached reparse points smb: client: get rid of smb311_posix_query_path_info() smb: client: parse owner/group when creating reparse points smb: client: fix parsing of SMB3.1.1 POSIX create context cifs: update known bugs mentioned in kernel docs for cifs cifs: new nt status codes from MS-SMB2 cifs: pick channel for tcon and tdis cifs: open_cached_dir should not rely on primary channel smb3: minor documentation updates Update MAINTAINERS email address cifs: minor comment cleanup smb3: show beginning time for per share stats cifs: remove redundant variable tcon_exist
2024-01-19Merge tag 'loongarch-6.8' of ↵Gravatar Linus Torvalds 1-11/+13
git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson Pull LoongArch updates from Huacai Chen: - Raise minimum clang version to 18.0.0 - Enable initial Rust support for LoongArch - Add built-in dtb support for LoongArch - Use generic interface to support crashkernel=X,[high,low] - Some bug fixes and other small changes - Update the default config file. * tag 'loongarch-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits) MAINTAINERS: Add BPF JIT for LOONGARCH entry LoongArch: Update Loongson-3 default config file LoongArch: BPF: Prevent out-of-bounds memory access LoongArch: BPF: Support 64-bit pointers to kfuncs LoongArch: Fix definition of ftrace_regs_set_instruction_pointer() LoongArch: Use generic interface to support crashkernel=X,[high,low] LoongArch: Fix and simplify fcsr initialization on execve() LoongArch: Let cores_io_master cover the largest NR_CPUS LoongArch: Change SHMLBA from SZ_64K to PAGE_SIZE LoongArch: Add a missing call to efi_esrt_init() LoongArch: Parsing CPU-related information from DTS LoongArch: dts: DeviceTree for Loongson-2K2000 LoongArch: dts: DeviceTree for Loongson-2K1000 LoongArch: dts: DeviceTree for Loongson-2K0500 LoongArch: Allow device trees be built into the kernel dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for interrupt-names dt-bindings: interrupt-controller: loongson,liointc: Fix dtbs_check warning for reg-names dt-bindings: loongarch: Add Loongson SoC boards compatibles dt-bindings: loongarch: Add CPU bindings for LoongArch LoongArch: Enable initial Rust support ...
2024-01-19cifs: update known bugs mentioned in kernel docs for cifsGravatar Steve French 1-7/+1
Remove bugs that have been addressed and add link to xfstest results wiki. Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-18smb3: minor documentation updatesGravatar Steve French 2-17/+27
Update the usage documentation to include some missing configuration options. Update the todo list documentation for cifs.ko Reviewed-by: Bharath SM <bharathsm@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2024-01-18Merge tag 'usb-6.8-rc1' of ↵Gravatar Linus Torvalds 1-0/+3
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB / Thunderbolt updates from Greg KH: "Here is the big set of USB and Thunderbolt changes for 6.8-rc1. Included in here are the following: - Thunderbolt subsystem and driver updates for USB 4 hardware and issues reported by real devices - xhci driver updates - dwc3 driver updates - uvc_video gadget driver updates - typec driver updates - gadget string functions cleaned up - other small changes All of these have been in the linux-next tree for a while with no reported issues" * tag 'usb-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (169 commits) usb: typec: tipd: fix use of device-specific init function usb: typec: tipd: Separate reset for TPS6598x usb: mon: Fix atomicity violation in mon_bin_vma_fault usb: gadget: uvc: Remove nested locking usb: gadget: uvc: Fix use are free during STREAMOFF usb: typec: class: fix typec_altmode_put_partner to put plugs dt-bindings: usb: dwc3: Limit num-hc-interrupters definition dt-bindings: usb: xhci: Add num-hc-interrupters definition xhci: add support to allocate several interrupters USB: core: Use device_driver directly in struct usb_driver and usb_device_driver arm64: dts: mediatek: mt8195: Add 'rx-fifo-depth' for cherry usb: xhci-mtk: fix a short packet issue of gen1 isoc-in transfer dt-bindings: usb: mtk-xhci: add a property for Gen1 isoc-in transfer issue arm64: dts: qcom: msm8996: Remove PNoC clock from MSS arm64: dts: qcom: msm8996: Remove AGGRE2 clock from SLPI arm64: dts: qcom: msm8998: Remove AGGRE2 clock from SLPI arm64: dts: qcom: msm8939: Drop RPM bus clocks arm64: dts: qcom: sdm630: Drop RPM bus clocks arm64: dts: qcom: qcs404: Drop RPM bus clocks arm64: dts: qcom: msm8996: Drop RPM bus clocks ...
2024-01-18Merge tag 'tty-6.8-rc1' of ↵Gravatar Linus Torvalds 2-1/+13
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty / serial updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.8-rc1. As usual, Jiri has a bunch of refactoring and cleanups for the tty core and drivers in here, along with the usual set of rs485 updates (someday this might work properly...) Along with those, in here are changes for: - sc16is7xx serial driver updates - platform driver removal api updates - amba-pl011 driver updates - tty driver binding updates - other small tty/serial driver updates and changes All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (197 commits) serial: sc16is7xx: refactor EFR lock serial: sc16is7xx: reorder code to remove prototype declarations serial: sc16is7xx: refactor FIFO access functions to increase commonality serial: sc16is7xx: drop unneeded MODULE_ALIAS serial: sc16is7xx: replace hardcoded divisor value with BIT() macro serial: sc16is7xx: add explicit return for some switch default cases serial: sc16is7xx: add macro for max number of UART ports serial: sc16is7xx: add driver name to struct uart_driver serial: sc16is7xx: use i2c_get_match_data() serial: sc16is7xx: use spi_get_device_match_data() serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield serial: sc16is7xx: improve do/while loop in sc16is7xx_irq() serial: sc16is7xx: remove obsolete loop in sc16is7xx_port_irq() serial: sc16is7xx: set safe default SPI clock frequency serial: sc16is7xx: add check for unsupported SPI modes during probe serial: sc16is7xx: fix invalid sc16is7xx_lines bitfield in case of probe error serial: 8250_exar: Set missing rs485_supported flag serial: omap: do not override settings for RS485 support serial: core, imx: do not set RS485 enabled if it is not supported serial: core: make sure RS485 cannot be enabled when it is not supported ...
2024-01-18Merge tag 'driver-core-6.8-rc1' of ↵Gravatar Linus Torvalds 1-2/+3
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here are the set of driver core and kernfs changes for 6.8-rc1. Nothing major in here this release cycle, just lots of small cleanups and some tweaks on kernfs that in the very end, got reverted and will come back in a safer way next release cycle. Included in here are: - more driver core 'const' cleanups and fixes - fw_devlink=rpm is now the default behavior - kernfs tiny changes to remove some string functions - cpu handling in the driver core is updated to work better on many systems that add topologies and cpus after booting - other minor changes and cleanups All of the cpu handling patches have been acked by the respective maintainers and are coming in here in one series. Everything has been in linux-next for a while with no reported issues" * tag 'driver-core-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (51 commits) Revert "kernfs: convert kernfs_idr_lock to an irq safe raw spinlock" kernfs: convert kernfs_idr_lock to an irq safe raw spinlock class: fix use-after-free in class_register() PM: clk: make pm_clk_add_notifier() take a const pointer EDAC: constantify the struct bus_type usage kernfs: fix reference to renamed function driver core: device.h: fix Excess kernel-doc description warning driver core: class: fix Excess kernel-doc description warning driver core: mark remaining local bus_type variables as const driver core: container: make container_subsys const driver core: bus: constantify subsys_register() calls driver core: bus: make bus_sort_breadthfirst() take a const pointer kernfs: d_obtain_alias(NULL) will do the right thing... driver core: Better advertise dev_err_probe() kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy() kernfs: Convert kernfs_name_locked() from strlcpy() to strscpy() kernfs: Convert kernfs_walk_ns() from strlcpy() to strscpy() initramfs: Expose retained initrd as sysfs file fs/kernfs/dir: obey S_ISGID kernel/cgroup: use kernfs_create_dir_ns() ...
2024-01-17Merge tag 'pm-6.8-rc1-2' of ↵Gravatar Linus Torvalds 2-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "These restore the asynchronous device resume optimization removed by the previous PM merge, make the intel_pstate driver work better on Meteor Lake systems, optimize the PM QoS core code slightly and fix up typos in admin-guide. Specifics: - Restore the system-wide asynchronous device resume optimization removed by a recent concurrency fix (Rafael J. Wysocki) - Make the intel_pstate cpufreq driver allow Meteor Lake systems to run at somewhat higher frequencies (Srinivas Pandruvada) - Make the PM QoS core code use kcalloc() for array allocation (Erick Archer) - Fix two PM-related typos in admin-guide (Erwan Velu)" * tag 'pm-6.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM: sleep: Restore asynchronous device resume optimization Documentation: admin-guide: PM: Fix two typos cpufreq: intel_pstate: Update hybrid scaling factor for Meteor Lake PM: QoS: Use kcalloc() instead of kzalloc()
2024-01-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmGravatar Linus Torvalds 1-3/+3
Pull kvm updates from Paolo Bonzini: "Generic: - Use memdup_array_user() to harden against overflow. - Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures. - Clean up Kconfigs that all KVM architectures were selecting - New functionality around "guest_memfd", a new userspace API that creates an anonymous file and returns a file descriptor that refers to it. guest_memfd files are bound to their owning virtual machine, cannot be mapped, read, or written by userspace, and cannot be resized. guest_memfd files do however support PUNCH_HOLE, which can be used to switch a memory area between guest_memfd and regular anonymous memory. - New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify per-page attributes for a given page of guest memory; right now the only attribute is whether the guest expects to access memory via guest_memfd or not, which in Confidential SVMs backed by SEV-SNP, TDX or ARM64 pKVM is checked by firmware or hypervisor that guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in the case of pKVM). x86: - Support for "software-protected VMs" that can use the new guest_memfd and page attributes infrastructure. This is mostly useful for testing, since there is no pKVM-like infrastructure to provide a meaningfully reduced TCB. - Fix a relatively benign off-by-one error when splitting huge pages during CLEAR_DIRTY_LOG. - Fix a bug where KVM could incorrectly test-and-clear dirty bits in non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with a non-huge SPTE. - Use more generic lockdep assertions in paths that don't actually care about whether the caller is a reader or a writer. - let Xen guests opt out of having PV clock reported as "based on a stable TSC", because some of them don't expect the "TSC stable" bit (added to the pvclock ABI by KVM, but never set by Xen) to be set. - Revert a bogus, made-up nested SVM consistency check for TLB_CONTROL. - Advertise flush-by-ASID support for nSVM unconditionally, as KVM always flushes on nested transitions, i.e. always satisfies flush requests. This allows running bleeding edge versions of VMware Workstation on top of KVM. - Sanity check that the CPU supports flush-by-ASID when enabling SEV support. - On AMD machines with vNMI, always rely on hardware instead of intercepting IRET in some cases to detect unmasking of NMIs - Support for virtualizing Linear Address Masking (LAM) - Fix a variety of vPMU bugs where KVM fail to stop/reset counters and other state prior to refreshing the vPMU model. - Fix a double-overflow PMU bug by tracking emulated counter events using a dedicated field instead of snapshotting the "previous" counter. If the hardware PMC count triggers overflow that is recognized in the same VM-Exit that KVM manually bumps an event count, KVM would pend PMIs for both the hardware-triggered overflow and for KVM-triggered overflow. - Turn off KVM_WERROR by default for all configs so that it's not inadvertantly enabled by non-KVM developers, which can be problematic for subsystems that require no regressions for W=1 builds. - Advertise all of the host-supported CPUID bits that enumerate IA32_SPEC_CTRL "features". - Don't force a masterclock update when a vCPU synchronizes to the current TSC generation, as updating the masterclock can cause kvmclock's time to "jump" unexpectedly, e.g. when userspace hotplugs a pre-created vCPU. - Use RIP-relative address to read kvm_rebooting in the VM-Enter fault paths, partly as a super minor optimization, but mostly to make KVM play nice with position independent executable builds. - Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on CONFIG_HYPERV as a minor optimization, and to self-document the code. - Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV "emulation" at build time. ARM64: - LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base granule sizes. Branch shared with the arm64 tree. - Large Fine-Grained Trap rework, bringing some sanity to the feature, although there is more to come. This comes with a prefix branch shared with the arm64 tree. - Some additional Nested Virtualization groundwork, mostly introducing the NV2 VNCR support and retargetting the NV support to that version of the architecture. - A small set of vgic fixes and associated cleanups. Loongarch: - Optimization for memslot hugepage checking - Cleanup and fix some HW/SW timer issues - Add LSX/LASX (128bit/256bit SIMD) support RISC-V: - KVM_GET_REG_LIST improvement for vector registers - Generate ISA extension reg_list using macros in get-reg-list selftest - Support for reporting steal time along with selftest s390: - Bugfixes Selftests: - Fix an annoying goof where the NX hugepage test prints out garbage instead of the magic token needed to run the test. - Fix build errors when a header is delete/moved due to a missing flag in the Makefile. - Detect if KVM bugged/killed a selftest's VM and print out a helpful message instead of complaining that a random ioctl() failed. - Annotate the guest printf/assert helpers with __printf(), and fix the various bugs that were lurking due to lack of said annotation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits) x86/kvm: Do not try to disable kvmclock if it was not enabled KVM: x86: add missing "depends on KVM" KVM: fix direction of dependency on MMU notifiers KVM: introduce CONFIG_KVM_COMMON KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache RISC-V: KVM: selftests: Add get-reg-list test for STA registers RISC-V: KVM: selftests: Add steal_time test support RISC-V: KVM: selftests: Add guest_sbi_probe_extension RISC-V: KVM: selftests: Move sbi_ecall to processor.c RISC-V: KVM: Implement SBI STA extension RISC-V: KVM: Add support for SBI STA registers RISC-V: KVM: Add support for SBI extension registers RISC-V: KVM: Add SBI STA info to vcpu_arch RISC-V: KVM: Add steal-update vcpu request RISC-V: KVM: Add SBI STA extension skeleton RISC-V: paravirt: Implement steal-time support RISC-V: Add SBI STA extension definitions RISC-V: paravirt: Add skeleton for pv-time support RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr() ...
2024-01-17Merge tag 'docs-6.8-2' of git://git.lwn.net/linuxGravatar Linus Torvalds 2-4/+3
Pull documentation fixes from Jonathan Corbet: "A handful of late-arriving documentation fixes" * tag 'docs-6.8-2' of git://git.lwn.net/linux: docs, kprobes: Add loongarch as supported architecture docs, kprobes: Update email address of Masami Hiramatsu docs: admin-guide: hw_random: update rng-tools website Documentation/core-api: fix spelling mistake in workqueue docs: kernel_feat.py: fix potential command injection Documentation: constrain alabaster package to older versions
2024-01-17LoongArch: Use generic interface to support crashkernel=X,[high,low]Gravatar Youling Tang 1-11/+13
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 0ab97169aa0517079b ("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>
2024-01-16Merge branches 'pm-sleep', 'pm-cpufreq' and 'pm-qos' into pmGravatar Rafael J. Wysocki 2-2/+2
* pm-sleep: PM: sleep: Restore asynchronous device resume optimization * pm-cpufreq: Documentation: admin-guide: PM: Fix two typos cpufreq: intel_pstate: Update hybrid scaling factor for Meteor Lake * pm-qos: PM: QoS: Use kcalloc() instead of kzalloc()
2024-01-12Merge tag 'rcu.release.v6.8' of https://github.com/neeraju/linuxGravatar Linus Torvalds 1-0/+6
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
2024-01-12Merge tag 'media/v6.8-2' of ↵Gravatar Linus Torvalds 4-0/+87
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 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 ...
2024-01-11Merge tag 'docs-6.8' of git://git.lwn.net/linuxGravatar Linus Torvalds 7-16/+19
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 ..
2024-01-11Merge tag 'net-next-6.8' of ↵Gravatar Linus Torvalds 1-1/+4
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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 ...
2024-01-11docs: admin-guide: hw_random: update rng-tools websiteGravatar Baruch Siach 1-3/+2
rng-tools upstream moved to github. New upstream does not appear to consider itself official website for hw_random. Drop that part. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/ef52ace5008fa934084442149f64f5f9ddbba465.1704720105.git.baruch@tkos.co.il
2024-01-11docs: kernel_feat.py: fix potential command injectionGravatar Vegard Nossum 1-1/+1
The kernel-feat directive passes its argument straight to the shell. This is unfortunate and unnecessary. Let's always use paths relative to $srctree/Documentation/ and use subprocess.check_call() instead of subprocess.Popen(shell=True). This also makes the code shorter. This is analogous to commit 3231dd586277 ("docs: kernel_abi.py: fix command injection") where we did exactly the same thing for kernel_abi.py, somehow I completely missed this one. Link: https://fosstodon.org/@jani/111676532203641247 Reported-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20240110174758.3680506-1-vegard.nossum@oracle.com
2024-01-10Documentation: admin-guide: PM: Fix two typosGravatar Erwan Velu 2-2/+2
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>
2024-01-09Merge tag 'platform-drivers-x86-v6.8-1' of ↵Gravatar Linus Torvalds 2-0/+25
git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86 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 ...
2024-01-09Merge tag 'regulator-v6.8' of ↵Gravatar Linus Torvalds 1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator 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 ...
2024-01-09Merge tag 'mm-stable-2024-01-08-15-31' of ↵Gravatar Linus Torvalds 10-79/+293
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm 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() ...
2024-01-08Merge tag 'cgroup-for-6.8' of ↵Gravatar Linus Torvalds 1-6/+27
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 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()
2024-01-08mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDERGravatar Kirill A. Shutemov 2-13/+13
commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has changed the definition of MAX_ORDER to be inclusive. This has caused issues with code that was not yet upstream and depended on the previous definition. To draw attention to the altered meaning of the define, rename MAX_ORDER to MAX_PAGE_ORDER. Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-08mm, treewide: introduce NR_PAGE_ORDERSGravatar Kirill A. Shutemov 1-3/+3
NR_PAGE_ORDERS defines the number of page orders supported by the page allocator, ranging from 0 to MAX_ORDER, MAX_ORDER + 1 in total. NR_PAGE_ORDERS assists in defining arrays of page orders and allows for more natural iteration over them. [kirill.shutemov@linux.intel.com: fixup for kerneldoc warning] Link: https://lkml.kernel.org/r/20240101111512.7empzyifq7kxtzk3@box Link: https://lkml.kernel.org/r/20231228144704.14033-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-03docs: kernel_abi.py: fix command injectionGravatar Vegard Nossum 4-4/+4
The kernel-abi directive passes its argument straight to the shell. This is unfortunate and unnecessary. Let's always use paths relative to $srctree/Documentation/ and use subprocess.check_call() instead of subprocess.Popen(shell=True). This also makes the code shorter. Link: https://fosstodon.org/@jani/111676532203641247 Reported-by: Jani Nikula <jani.nikula@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231231235959.3342928-2-vegard.nossum@oracle.com
2023-12-30RISC-V: paravirt: Add skeleton for pv-time supportGravatar Andrew Jones 1-3/+3
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>
2023-12-29zswap: memcontrol: implement zswap writeback disablingGravatar Nhat Pham 2-0/+25
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>
2023-12-29mm/ksm: document ksm advisor and its sysfs knobsGravatar Stefan Roesch 1-0/+55
This documents the KSM advisor and its new knobs in /sys/fs/kernel/mm. Link: https://lkml.kernel.org/r/20231218231054.1625219-5-shr@devkernel.io Signed-off-by: Stefan Roesch <shr@devkernel.io> Acked-by: David Hildenbrand <david@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29userfaultfd: UFFDIO_MOVE uABIGravatar Andrea Arcangeli 1-0/+3
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>
2023-12-20Docs/admin-guide/mm/damon/usage: use a list for 'state' sysfs file input ↵Gravatar SeongJae Park 1-24/+23
commands 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>
2023-12-20Docs/admin-guide/mm/damon/usage: add links to sysfs files hierarchyGravatar SeongJae Park 1-21/+49
'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>
2023-12-20Docs/admin-guide/mm/damon/usage: update context directory section labelGravatar SeongJae Park 1-3/+3
The label for context DAMON sysfs directory section is having name sysfs_contexts. The name would be better to be used for the contexts directory. Rename it to represent a single context. Link: https://lkml.kernel.org/r/20231213190338.54146-5-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>
2023-12-20mm: thp: introduce multi-size THP sysfs interfaceGravatar Ryan Roberts 1-19/+78
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>
2023-12-18platform/x86/amd/pmf: Add support to update system stateGravatar Shyam Sundar S K 2-0/+25
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>
2023-12-15Documentation, mm/unaccepted: document accept_memory kernel parameterGravatar Vlastimil Babka 1-0/+11
The accept_memory kernel parameter was added in commit dcdfdd40fa82 ("mm: Add support for unaccepted memory") but not listed in the kernel-parameters doc. Add it there. Acked-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231214-accept_memory_param-v2-1-f38cd20a0247@suse.cz
2023-12-15initramfs: Expose retained initrd as sysfs fileGravatar Alexander Graf 1-2/+3
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>
2023-12-15Documentation: Remove redundant file names from examplesGravatar Rex Nie 1-3/+3
Since most examples use the ddcmd alias, remove the redundant file names Signed-off-by: Rex Nie <rex.nie@jaguarmicro.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20231213073735.2850-1-rex.nie@jaguarmicro.com
2023-12-15net: increase optmem_max default valueGravatar Eric Dumazet 1-1/+4
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>
2023-12-13docs: perf: Add description for Synopsys DesignWare PCIe PMU driverGravatar Shuai Xue 2-0/+95
Alibaba's T-Head Yitan 710 SoC includes Synopsys' DesignWare Core PCIe controller which implements PMU for performance and functional debugging to facilitate system maintenance. Document it to provide guidance on how to use it. Signed-off-by: Shuai Xue <xueshuai@linux.alibaba.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Yicong Yang <yangyicong@hisilicon.com> Tested-by: Ilkka Koskinen <ilkka@os.amperecomputing.com> Link: https://lore.kernel.org/r/20231208025652.87192-2-xueshuai@linux.alibaba.com Signed-off-by: Will Deacon <will@kernel.org>
2023-12-12Docs/admin-guide/mm/damon/usage: document for quota goalsGravatar SeongJae Park 1-7/+41
Update DAMON sysfs usage for newly added DAMOS quota goals interface. Link: https://lkml.kernel.org/r/20231130023652.50284-10-sj@kernel.org Signed-off-by: SeongJae Park <sj@kernel.org> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: David Gow <davidgow@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-12zswap: shrink zswap pool based on memory pressureGravatar Nhat Pham 1-0/+10
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>
2023-12-12rcu: Restrict access to RCU CPU stall notifiersGravatar Paul E. McKenney 1-0/+6
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 5b404fdabacf ("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: 5b404fdabacf ("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>
2023-12-10zram: split memory-tracking and ac-time trackingGravatar Sergey Senozhatsky 1-1/+1
ZRAM_MEMORY_TRACKING enables two features: - per-entry ac-time tracking - debugfs interface The latter one is the reason why memory-tracking depends on DEBUG_FS, while the former one is used far beyond debugging these days. Namely ac-time is used for fine grained writeback of idle entries (pages). Move ac-time tracking under its own config option so that it can be enabled (along with writeback) on systems without DEBUG_FS. [senozhatsky@chromium.org: ifdef fixup, per Dmytro] Link: https://lkml.kernel.org/r/20231117013543.540280-1-senozhatsky@chromium.org Link: https://lkml.kernel.org/r/20231115024223.4133148-1-senozhatsky@chromium.org Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dmytro Maluka <dmaluka@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10fs/proc/task_mmu: report SOFT_DIRTY bits through the PAGEMAP_SCAN ioctlGravatar Andrei Vagin 1-0/+1
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>
2023-12-07doc: media: visl: Add AV1 supportGravatar Detlev Casanova 1-0/+2
Add AV1 information in visl documentation. Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
2023-12-05docs/perf: Add explanation for DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER quirkGravatar Xu Yang 1-8/+37
Add explanation for DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER quirk. Signed-off-by: Xu Yang <xu.yang_2@nxp.com> Link: https://lore.kernel.org/r/20231120093317.2652866-2-xu.yang_2@nxp.com Signed-off-by: Will Deacon <will@kernel.org>
2023-12-01cgroup: Fix documentation for cpu.idleGravatar Josh Don 1-1/+15
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>