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2026-04-16Merge tag 'mm-nonmm-stable-2026-04-15-04-20' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "pid: make sub-init creation retryable" (Oleg Nesterov) Make creation of init in a new namespace more robust by clearing away some historical cruft which is no longer needed. Also some documentation fixups - "selftests/fchmodat2: Error handling and general" (Mark Brown) Fix and a cleanup for the fchmodat2() syscall selftest - "lib: polynomial: Move to math/ and clean up" (Andy Shevchenko) - "hung_task: Provide runtime reset interface for hung task detector" (Aaron Tomlin) Give administrators the ability to zero out /proc/sys/kernel/hung_task_detect_count - "tools/getdelays: use the static UAPI headers from tools/include/uapi" (Thomas Weißschuh) Teach getdelays to use the in-kernel UAPI headers rather than the system-provided ones - "watchdog/hardlockup: Improvements to hardlockup" (Mayank Rungta) Several cleanups and fixups to the hardlockup detector code and its documentation - "lib/bch: fix undefined behavior from signed left-shifts" (Josh Law) A couple of small/theoretical fixes in the bch code - "ocfs2/dlm: fix two bugs in dlm_match_regions()" (Junrui Luo) - "cleanup the RAID5 XOR library" (Christoph Hellwig) A quite far-reaching cleanup to this code. I can't do better than to quote Christoph: "The XOR library used for the RAID5 parity is a bit of a mess right now. The main file sits in crypto/ despite not being cryptography and not using the crypto API, with the generic implementations sitting in include/asm-generic and the arch implementations sitting in an asm/ header in theory. The latter doesn't work for many cases, so architectures often build the code directly into the core kernel, or create another module for the architecture code. Change this to a single module in lib/ that also contains the architecture optimizations, similar to the library work Eric Biggers has done for the CRC and crypto libraries later. After that it changes to better calling conventions that allow for smarter architecture implementations (although none is contained here yet), and uses static_call to avoid indirection function call overhead" - "lib/list_sort: Clean up list_sort() scheduling workarounds" (Kuan-Wei Chiu) Clean up this library code by removing a hacky thing which was added for UBIFS, which UBIFS doesn't actually need - "Fix bugs in extract_iter_to_sg()" (Christian Ehrhardt) Fix a few bugs in the scatterlist code, add in-kernel tests for the now-fixed bugs and fix a leak in the test itself - "kdump: Enable LUKS-encrypted dump target support in ARM64 and PowerPC" (Coiby Xu) Enable support of the LUKS-encrypted device dump target on arm64 and powerpc - "ocfs2: consolidate extent list validation into block read callbacks" (Joseph Qi) Cleanup, simplify, and make more robust ocfs2's validation of extent list fields (Kernel test robot loves mounting corrupted fs images!) * tag 'mm-nonmm-stable-2026-04-15-04-20' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (127 commits) ocfs2: validate group add input before caching ocfs2: validate bg_bits during freefrag scan ocfs2: fix listxattr handling when the buffer is full doc: watchdog: fix typos etc update Sean's email address ocfs2: use get_random_u32() where appropriate ocfs2: split transactions in dio completion to avoid credit exhaustion ocfs2: remove redundant l_next_free_rec check in __ocfs2_find_path() ocfs2: validate extent block list fields during block read ocfs2: remove empty extent list check in ocfs2_dx_dir_lookup_rec() ocfs2: validate dx_root extent list fields during block read ocfs2: fix use-after-free in ocfs2_fault() when VM_FAULT_RETRY ocfs2: handle invalid dinode in ocfs2_group_extend .get_maintainer.ignore: add Askar ocfs2: validate bg_list extent bounds in discontig groups checkpatch: exclude forward declarations of const structs tools/accounting: handle truncated taskstats netlink messages taskstats: set version in TGID exit notifications ocfs2/heartbeat: fix slot mapping rollback leaks on error paths arm64,ppc64le/kdump: pass dm-crypt keys to kdump kernel ...
2026-04-14Merge tag 'net-next-7.1' of ↵Linus Torvalds1-0/+28
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core & protocols: - Support HW queue leasing, allowing containers to be granted access to HW queues for zero-copy operations and AF_XDP - Number of code moves to help the compiler with inlining. Avoid output arguments for returning drop reason where possible - Rework drop handling within qdiscs to include more metadata about the reason and dropping qdisc in the tracepoints - Remove the rtnl_lock use from IP Multicast Routing - Pack size information into the Rx Flow Steering table pointer itself. This allows making the table itself a flat array of u32s, thus making the table allocation size a power of two - Report TCP delayed ack timer information via socket diag - Add ip_local_port_step_width sysctl to allow distributing the randomly selected ports more evenly throughout the allowed space - Add support for per-route tunsrc in IPv6 segment routing - Start work of switching sockopt handling to iov_iter - Improve dynamic recvbuf sizing in MPTCP, limit burstiness and avoid buffer size drifting up - Support MSG_EOR in MPTCP - Add stp_mode attribute to the bridge driver for STP mode selection. This addresses concerns about call_usermodehelper() usage - Remove UDP-Lite support (as announced in 2023) - Remove support for building IPv6 as a module. Remove the now unnecessary function calling indirection Cross-tree stuff: - Move Michael MIC code from generic crypto into wireless, it's considered insecure but some WiFi networks still need it Netfilter: - Switch nft_fib_ipv6 module to no longer need temporary dst_entry object allocations by using fib6_lookup() + RCU. Florian W reports this gets us ~13% higher packet rate - Convert IPVS's global __ip_vs_mutex to per-net service_mutex and switch the service tables to be per-net. Convert some code that walks the service lists to use RCU instead of the service_mutex - Add more opinionated input validation to lower security exposure - Make IPVS hash tables to be per-netns and resizable Wireless: - Finished assoc frame encryption/EPPKE/802.1X-over-auth - Radar detection improvements - Add 6 GHz incumbent signal detection APIs - Multi-link support for FILS, probe response templates and client probing - New APIs and mac80211 support for NAN (Neighbor Aware Networking, aka Wi-Fi Aware) so less work must be in firmware Driver API: - Add numerical ID for devlink instances (to avoid having to create fake bus/device pairs just to have an ID). Support shared devlink instances which span multiple PFs - Add standard counters for reporting pause storm events (implement in mlx5 and fbnic) - Add configuration API for completion writeback buffering (implement in mana) - Support driver-initiated change of RSS context sizes - Support DPLL monitoring input frequency (implement in zl3073x) - Support per-port resources in devlink (implement in mlx5) Misc: - Expand the YAML spec for Netfilter Drivers - Software: - macvlan: support multicast rx for bridge ports with shared source MAC address - team: decouple receive and transmit enablement for IEEE 802.3ad LACP "independent control" - Ethernet high-speed NICs: - nVidia/Mellanox: - support high order pages in zero-copy mode (for payload coalescing) - support multiple packets in a page (for systems with 64kB pages) - Broadcom 25-400GE (bnxt): - implement XDP RSS hash metadata extraction - add software fallback for UDP GSO, lowering the IOMMU cost - Broadcom 800GE (bnge): - add link status and configuration handling - add various HW and SW statistics - Marvell/Cavium: - NPC HW block support for cn20k - Huawei (hinic3): - add mailbox / control queue - add rx VLAN offload - add driver info and link management - Ethernet NICs: - Marvell/Aquantia: - support reading SFP module info on some AQC100 cards - Realtek PCI (r8169): - add support for RTL8125cp - Realtek USB (r8152): - support for the RTL8157 5Gbit chip - add 2500baseT EEE status/configuration support - Ethernet NICs embedded and off-the-shelf IP: - Synopsys (stmmac): - cleanup and reorganize SerDes handling and PCS support - cleanup descriptor handling and per-platform data - cleanup and consolidate MDIO defines and handling - shrink driver memory use for internal structures - improve Tx IRQ coalescing - improve TCP segmentation handling - add support for Spacemit K3 - Cadence (macb): - support PHYs that have inband autoneg disabled with GEM - support IEEE 802.3az EEE - rework usrio capabilities and handling - AMD (xgbe): - improve power management for S0i3 - improve TX resilience for link-down handling - Virtual: - Google cloud vNIC: - support larger ring sizes in DQO-QPL mode - improve HW-GRO handling - support UDP GSO for DQO format - PCIe NTB: - support queue count configuration - Ethernet PHYs: - automatically disable PHY autonomous EEE if MAC is in charge - Broadcom: - add BCM84891/BCM84892 support - Micrel: - support for LAN9645X internal PHY - Realtek: - add RTL8224 pair order support - support PHY LEDs on RTL8211F-VD - support spread spectrum clocking (SSC) - Maxlinear: - add PHY-level statistics via ethtool - Ethernet switches: - Maxlinear (mxl862xx): - support for bridge offloading - support for VLANs - support driver statistics - Bluetooth: - large number of fixes and new device IDs - Mediatek: - support MT6639 (MT7927) - support MT7902 SDIO - WiFi: - Intel (iwlwifi): - UNII-9 and continuing UHR work - MediaTek (mt76): - mt7996/mt7925 MLO fixes/improvements - mt7996 NPU support (HW eth/wifi traffic offload) - Qualcomm (ath12k): - monitor mode support on IPQ5332 - basic hwmon temperature reporting - support IPQ5424 - Realtek: - add USB RX aggregation to improve performance - add USB TX flow control by tracking in-flight URBs - Cellular: - IPA v5.2 support" * tag 'net-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1561 commits) net: pse-pd: fix kernel-doc function name for pse_control_find_by_id() wireguard: device: use exit_rtnl callback instead of manual rtnl_lock in pre_exit wireguard: allowedips: remove redundant space tools: ynl: add sample for wireguard wireguard: allowedips: Use kfree_rcu() instead of call_rcu() MAINTAINERS: Add netkit selftest files selftests/net: Add additional test coverage in nk_qlease selftests/net: Split netdevsim tests from HW tests in nk_qlease tools/ynl: Make YnlFamily closeable as a context manager net: airoha: Add missing PPE configurations in airoha_ppe_hw_init() net: airoha: Fix VIP configuration for AN7583 SoC net: caif: clear client service pointer on teardown net: strparser: fix skb_head leak in strp_abort_strp() net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete() selftests/bpf: add test for xdp_master_redirect with bond not up net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master net: airoha: Remove PCE_MC_EN_MASK bit in REG_FE_PCE_CFG configuration sctp: disable BH before calling udp_tunnel_xmit_skb() sctp: fix missing encap_port propagation for GSO fragments net: airoha: Rely on net_device pointer in ETS callbacks ...
2026-04-14Merge tag 'docs-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds4-3/+136
Pull documentation updates from Jonathan Corbet: "A busier cycle than I had expected for docs, including: - Translations: some overdue updates to the Japanese translations, Chinese translations for some of the Rust documentation, and the beginnings of a Portuguese translation. - New documents covering CPU isolation, managed interrupts, debugging Python gbb scripts, and more. - More tooling work from Mauro, reducing docs-build warnings, adding self tests, improving man-page output, bringing in a proper C tokenizer to replace (some of) the mess of kernel-doc regexes, and more. - Update and synchronize changes.rst and scripts/ver_linux, and put both into alphabetical order. ... and a long list of documentation updates, typo fixes, and general improvements" * tag 'docs-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (162 commits) Documentation: core-api: real-time: correct spelling doc: Add CPU Isolation documentation Documentation: Add managed interrupts Documentation: seq_file: drop 2.6 reference docs/zh_CN: update rust/index.rst translation docs/zh_CN: update rust/quick-start.rst translation docs/zh_CN: update rust/coding-guidelines.rst translation docs/zh_CN: update rust/arch-support.rst translation docs/zh_CN: sync process/2.Process.rst with English version docs/zh_CN: fix an inconsistent statement in dev-tools/testing-overview tracing: Documentation: Update histogram-design.rst for fn() handling docs: sysctl: Add documentation for /proc/sys/xen/ Docs: hid: intel-ish-hid: make long URL usable Documentation/kernel-parameters: fix architecture alignment for pt, nopt, and nobypass sched/doc: Update yield_task description in sched-design-CFS Documentation/rtla: Convert links to RST format docs: fix typos and duplicated words across documentation docs: fix typo in zoran driver documentation docs: add an Assisted-by mention to submitting-patches.rst Revert "scripts/checkpatch: add Assisted-by: tag validation" ...
2026-04-09docs: sysctl: Add documentation for /proc/sys/xen/Shubham Chakraborty2-1/+33
Add documentation for the Xen hypervisor sysctl controls in /proc/sys/xen/balloon/. Documents the hotplug_unpopulated tunable (available when CONFIG_XEN_BALLOON_MEMORY_HOTPLUG is enabled) which controls whether unpopulated memory regions are automatically hotplugged when the Xen balloon driver needs to reclaim memory. The documentation is based on source code analysis of drivers/xen/balloon.c. Signed-off-by: Shubham Chakraborty <chakrabortyshubham66@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260304150419.16738-1-chakrabortyshubham66@gmail.com>
2026-03-27hung_task: enable runtime reset of hung_task_detect_countAaron Tomlin1-1/+2
Currently, the hung_task_detect_count sysctl provides a cumulative count of hung tasks since boot. In long-running, high-availability environments, this counter may lose its utility if it cannot be reset once an incident has been resolved. Furthermore, the previous implementation relied upon implicit ordering, which could not strictly guarantee that diagnostic metadata published by one CPU was visible to the panic logic on another. This patch introduces the capability to reset the detection count by writing "0" to the hung_task_detect_count sysctl. The proc_handler logic has been updated to validate this input and atomically reset the counter. The synchronisation of sysctl_hung_task_detect_count relies upon a transactional model to ensure the integrity of the detection counter against concurrent resets from userspace. The application of atomic_long_read_acquire() and atomic_long_cmpxchg_release() is correct and provides the following guarantees: 1. Prevention of Load-Store Reordering via Acquire Semantics By utilising atomic_long_read_acquire() to snapshot the counter before initiating the task traversal, we establish a strict memory barrier. This prevents the compiler or hardware from reordering the initial load to a point later in the scan. Without this "acquire" barrier, a delayed load could potentially read a "0" value resulting from a userspace reset that occurred mid-scan. This would lead to the subsequent cmpxchg succeeding erroneously, thereby overwriting the user's reset with stale increment data. 2. Atomicity of the "Commit" Phase via Release Semantics The atomic_long_cmpxchg_release() serves as the transaction's commit point. The "release" barrier ensures that all diagnostic recordings and task-state observations made during the scan are globally visible before the counter is incremented. 3. Race Condition Resolution This pairing effectively detects any "out-of-band" reset of the counter. If sysctl_hung_task_detect_count is modified via the procfs interface during the scan, the final cmpxchg will detect the discrepancy between the current value and the "acquire" snapshot. Consequently, the update will fail, ensuring that a reset command from the administrator is prioritised over a scan that may have been invalidated by that very reset. Link: https://lkml.kernel.org/r/20260303203031.4097316-3-atomlin@atomlin.com Signed-off-by: Aaron Tomlin <atomlin@atomlin.com> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Joel Granados <joel.granados@kernel.org> Reviewed-by: Petr Mladek <pmladek@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Lance Yang <lance.yang@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-12vsock: add G2H fallback for CIDs not owned by H2G transportAlexander Graf1-0/+28
When no H2G transport is loaded, vsock currently routes all CIDs to the G2H transport (commit 65b422d9b61b ("vsock: forward all packets to the host when no H2G is registered"). Extend that existing behavior: when an H2G transport is loaded but does not claim a given CID, the connection falls back to G2H in the same way. This matters in environments like Nitro Enclaves, where an instance may run nested VMs via vhost-vsock (H2G) while also needing to reach sibling enclaves at higher CIDs through virtio-vsock-pci (G2H). With the old code, any CID > 2 was unconditionally routed to H2G when vhost was loaded, making those enclaves unreachable without setting VMADDR_FLAG_TO_HOST explicitly on every connect. Requiring every application to set VMADDR_FLAG_TO_HOST creates friction: tools like socat, iperf, and others would all need to learn about it. The flag was introduced 6 years ago and I am still not aware of any tool that supports it. Even if there was support, it would be cumbersome to use. The most natural experience is a single CID address space where H2G only wins for CIDs it actually owns, and everything else falls through to G2H, extending the behavior that already exists when H2G is absent. To give user space at least a hint that the kernel applied this logic, automatically set the VMADDR_FLAG_TO_HOST on the remote address so it can determine the path taken via getpeername(). Add a per-network namespace sysctl net.vsock.g2h_fallback (default 1). At 0 it forces strict routing: H2G always wins for CID > VMADDR_CID_HOST, or ENODEV if H2G is not loaded. Signed-off-by: Alexander Graf <graf@amazon.com> Tested-by: syzbot@syzkaller.appspotmail.com Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260304230027.59857-1-graf@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-03-03docs: sysctl: add documentation for crypto and debugShubham Chakraborty3-2/+103
Add documentation for the /proc/sys/crypto and /proc/sys/debug directories in the admin-guide. This includes tunables for FIPS mode (fips_enabled, fips_name, fips_version), exception-trace, and kprobes-optimization. The documentation is based on source code analysis and addresses stylistic feedback to keep it direct and concise. Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Shubham Chakraborty <chakrabortyshubham66@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Message-ID: <20260223203724.20874-1-chakrabortyshubham66@gmail.com>
2026-02-26vsock: document write-once behavior of the child_ns_mode sysctlBobby Eshleman1-0/+3
Update the vsock child_ns_mode documentation to include the new write-once semantics of setting child_ns_mode. The semantics are implemented in a preceding patch in this series. Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260223-vsock-ns-write-once-v3-3-c0cde6959923@meta.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-02-19Merge tag 'net-7.0-rc1' of ↵Linus Torvalds1-2/+50
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from Netfilter. Current release - new code bugs: - net: fix backlog_unlock_irq_restore() vs CONFIG_PREEMPT_RT - eth: mlx5e: XSK, Fix unintended ICOSQ change - phy_port: correctly recompute the port's linkmodes - vsock: prevent child netns mode switch from local to global - couple of kconfig fixes for new symbols Previous releases - regressions: - nfc: nci: fix false-positive parameter validation for packet data - net: do not delay zero-copy skbs in skb_attempt_defer_free() Previous releases - always broken: - mctp: ensure our nlmsg responses to user space are zero-initialised - ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data() - fixes for ICMP rate limiting Misc: - intel: fix PCI device ID conflict between i40e and ipw2200" * tag 'net-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (85 commits) net: nfc: nci: Fix parameter validation for packet data net/mlx5e: Use unsigned for mlx5e_get_max_num_channels net/mlx5e: Fix deadlocks between devlink and netdev instance locks net/mlx5e: MACsec, add ASO poll loop in macsec_aso_set_arm_event net/mlx5: Fix misidentification of write combining CQE during poll loop net/mlx5e: Fix misidentification of ASO CQE during poll loop net/mlx5: Fix multiport device check over light SFs bonding: alb: fix UAF in rlb_arp_recv during bond up/down bnge: fix reserving resources from FW eth: fbnic: Advertise supported XDP features. rds: tcp: fix uninit-value in __inet_bind net/rds: Fix NULL pointer dereference in rds_tcp_accept_one octeontx2-af: Fix default entries mcam entry action net/mlx5e: XSK, Fix unintended ICOSQ change ipv6: icmp: icmpv6_xrlim_allow() optimization if net.ipv6.icmp.ratelimit is zero ipv4: icmp: icmpv4_xrlim_allow() optimization if net.ipv4.icmp_ratelimit is zero ipv6: icmp: remove obsolete code in icmpv6_xrlim_allow() inet: move icmp_global_{credit,stamp} to a separate cache line icmp: prevent possible overflow in icmp_global_allow() selftests/net: packetdrill: add ipv4-mapped-ipv6 tests ...
2026-02-17vsock: document namespace mode sysctlsStefano Garzarella1-2/+50
Add documentation for the vsock per-namespace sysctls (`ns_mode` and `child_ns_mode`) to Documentation/admin-guide/sysctl/net.rst. These sysctls were introduced by commit eafb64f40ca4 ("vsock: add netns to vsock core"). Document the two namespace modes (`global` and `local`), the inheritance behavior of `child_ns_mode`, and the restriction preventing local namespaces from setting `child_ns_mode` to `global`. Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Tested-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Link: https://patch.msgid.link/20260216163147.236844-1-sgarzare@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-12Merge tag 'mm-stable-2026-02-11-19-22' of ↵Linus Torvalds1-8/+28
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "powerpc/64s: do not re-activate batched TLB flush" makes arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev) It adds a generic enter/leave layer and switches architectures to use it. Various hacks were removed in the process. - "zram: introduce compressed data writeback" implements data compression for zram writeback (Richard Chang and Sergey Senozhatsky) - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous page ranges for hugepages. Large improvements during demand faulting are demonstrated (David Hildenbrand) - "memcg cleanups" tidies up some memcg code (Chen Ridong) - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos stats" improves DAMOS stat's provided information, deterministic control, and readability (SeongJae Park) - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few issues in the hugetlb cgroup charging selftests (Li Wang) - "Fix va_high_addr_switch.sh test failure - again" addresses several issues in the va_high_addr_switch test (Chunyu Hu) - "mm/damon/tests/core-kunit: extend existing test scenarios" improves the KUnit test coverage for DAMON (Shu Anzai) - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN (Shivank Garg) - "arch, mm: consolidate hugetlb early reservation" reworks and consolidates a pile of straggly code related to reservation of hugetlb memory from bootmem and creation of CMA areas for hugetlb (Mike Rapoport) - "mm: clean up anon_vma implementation" cleans up the anon_vma implementation in various ways (Lorenzo Stoakes) - "tweaks for __alloc_pages_slowpath()" does a little streamlining of the page allocator's slowpath code (Vlastimil Babka) - "memcg: separate private and public ID namespaces" cleans up the memcg ID code and prevents the internal-only private IDs from being exposed to userspace (Shakeel Butt) - "mm: hugetlb: allocate frozen gigantic folio" cleans up the allocation of frozen folios and avoids some atomic refcount operations (Kefeng Wang) - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement of memory betewwn the active and inactive LRUs and adds auto-tuning of the ratio-based quotas and of monitoring intervals (SeongJae Park) - "Support page table check on PowerPC" makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan) - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes nodes_and() and nodes_andnot() propagate the return values from the underlying bit operations, enabling some cleanup in calling code (Yury Norov) - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up some DAMON internal interfaces (SeongJae Park) - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work in khupaged and fixes a scan limit accounting issue (Shivank Garg) - "mm: balloon infrastructure cleanups" goes to town on the balloon infrastructure and its page migration function. Mainly cleanups, also some locking simplification (David Hildenbrand) - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds additional tracepoints to the page reclaim code (Jiayuan Chen) - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is part of Marco's kernel-wide migration from the legacy workqueue APIs over to the preferred unbound workqueues (Marco Crivellari) - "Various mm kselftests improvements/fixes" provides various unrelated improvements/fixes for the mm kselftests (Kevin Brodsky) - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic folio allocation, mainly by avoiding unnecessary work in pfn_range_valid_contig() (Kefeng Wang) - "selftests/damon: improve leak detection and wss estimation reliability" improves the reliability of two of the DAMON selftests (SeongJae Park) - "mm/damon: cleanup kdamond, damon_call(), damos filter and DAMON_MIN_REGION" does some cleanup work in the core DAMON code (SeongJae Park) - "Docs/mm/damon: update intro, modules, maintainer profile, and misc" performs maintenance work on the DAMON documentation (SeongJae Park) - "mm: add and use vma_assert_stabilised() helper" refactors and cleans up the core VMA code. The main aim here is to be able to use the mmap write lock's lockdep state to perform various assertions regarding the locking which the VMA code requires (Lorenzo Stoakes) - "mm, swap: swap table phase II: unify swapin use" removes some old swap code (swap cache bypassing and swap synchronization) which wasn't working very well. Various other cleanups and simplifications were made. The end result is a 20% speedup in one benchmark (Kairui Song) - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM available on 64-bit alpha, loongarch, mips, parisc, and um. Various cleanups were performed along the way (Qi Zheng) * tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits) mm/memory: handle non-split locks correctly in zap_empty_pte_table() mm: move pte table reclaim code to memory.c mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config um: mm: enable MMU_GATHER_RCU_TABLE_FREE parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE mips: mm: enable MMU_GATHER_RCU_TABLE_FREE LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles zsmalloc: make common caches global mm: add SPDX id lines to some mm source files mm/zswap: use %pe to print error pointers mm/vmscan: use %pe to print error pointers mm/readahead: fix typo in comment mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file() mm: refactor vma_map_pages to use vm_insert_pages mm/damon: unify address range representation with damon_addr_range mm/cma: replace snprintf with strscpy in cma_new_area ...
2026-02-11Merge tag 'net-next-7.0' of ↵Linus Torvalds1-6/+7
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "Core & protocols: - A significant effort all around the stack to guide the compiler to make the right choice when inlining code, to avoid unneeded calls for small helper and stack canary overhead in the fast-path. This generates better and faster code with very small or no text size increases, as in many cases the call generated more code than the actual inlined helper. - Extend AccECN implementation so that is now functionally complete, also allow the user-space enabling it on a per network namespace basis. - Add support for memory providers with large (above 4K) rx buffer. Paired with hw-gro, larger rx buffer sizes reduce the number of buffers traversing the stack, dincreasing single stream CPU usage by up to ~30%. - Do not add HBH header to Big TCP GSO packets. This simplifies the RX path, the TX path and the NIC drivers, and is possible because user-space taps can now interpret correctly such packets without the HBH hint. - Allow IPv6 routes to be configured with a gateway address that is resolved out of a different interface than the one specified, aligning IPv6 to IPv4 behavior. - Multi-queue aware sch_cake. This makes it possible to scale the rate shaper of sch_cake across multiple CPUs, while still enforcing a single global rate on the interface. - Add support for the nbcon (new buffer console) infrastructure to netconsole, enabling lock-free, priority-based console operations that are safer in crash scenarios. - Improve the TCP ipv6 output path to cache the flow information, saving cpu cycles, reducing cache line misses and stack use. - Improve netfilter packet tracker to resolve clashes for most protocols, avoiding unneeded drops on rare occasions. - Add IP6IP6 tunneling acceleration to the flowtable infrastructure. - Reduce tcp socket size by one cache line. - Notify neighbour changes atomically, avoiding inconsistencies between the notification sequence and the actual states sequence. - Add vsock namespace support, allowing complete isolation of vsocks across different network namespaces. - Improve xsk generic performances with cache-alignment-oriented optimizations. - Support netconsole automatic target recovery, allowing netconsole to reestablish targets when underlying low-level interface comes back online. Driver API: - Support for switching the working mode (automatic vs manual) of a DPLL device via netlink. - Introduce PHY ports representation to expose multiple front-facing media ports over a single MAC. - Introduce "rx-polarity" and "tx-polarity" device tree properties, to generalize polarity inversion requirements for differential signaling. - Add helper to create, prepare and enable managed clocks. Device drivers: - Add Huawei hinic3 PF etherner driver. - Add DWMAC glue driver for Motorcomm YT6801 PCIe ethernet controller. - Add ethernet driver for MaxLinear MxL862xx switches - Remove parallel-port Ethernet driver. - Convert existing driver timestamp configuration reporting to hwtstamp_get and remove legacy ioctl(). - Convert existing drivers to .get_rx_ring_count(), simplifing the RX ring count retrieval. Also remove the legacy fallback path. - Ethernet high-speed NICs: - Broadcom (bnxt, bng): - bnxt: add FW interface update to support FEC stats histogram and NVRAM defragmentation - bng: add TSO and H/W GRO support - nVidia/Mellanox (mlx5): - improve latency of channel restart operations, reducing the used H/W resources - add TSO support for UDP over GRE over VLAN - add flow counters support for hardware steering (HWS) rules - use a static memory area to store headers for H/W GRO, leading to 12% RX tput improvement - Intel (100G, ice, idpf): - ice: reorganizes layout of Tx and Rx rings for cacheline locality and utilizes __cacheline_group* macros on the new layouts - ice: introduces Synchronous Ethernet (SyncE) support - Meta (fbnic): - adds debugfs for firmware mailbox and tx/rx rings vectors - Ethernet virtual: - geneve: introduce GRO/GSO support for double UDP encapsulation - Ethernet NICs consumer, and embedded: - Synopsys (stmmac): - some code refactoring and cleanups - RealTek (r8169): - add support for RTL8127ATF (10G Fiber SFP) - add dash and LTR support - Airoha: - AN8811HB 2.5 Gbps phy support - Freescale (fec): - add XDP zero-copy support - Thunderbolt: - add get link setting support to allow bonding - Renesas: - add support for RZ/G3L GBETH SoC - Ethernet switches: - Maxlinear: - support R(G)MII slow rate configuration - add support for Intel GSW150 - Motorcomm (yt921x): - add DCB/QoS support - TI: - icssm-prueth: support bridging (STP/RSTP) via the switchdev framework - Ethernet PHYs: - Realtek: - enable SGMII and 2500Base-X in-band auto-negotiation - simplify and reunify C22/C45 drivers - Micrel: convert bindings to DT schema - CAN: - move skb headroom content into skb extensions, making CAN metadata access more robust - CAN drivers: - rcar_canfd: - add support for FD-only mode - add support for the RZ/T2H SoC - sja1000: cleanup the CAN state handling - WiFi: - implement EPPKE/802.1X over auth frames support - split up drop reasons better, removing generic RX_DROP - additional FTM capabilities: 6 GHz support, supported number of spatial streams and supported number of LTF repetitions - better mac80211 iterators to enumerate resources - initial UHR (Wi-Fi 8) support for cfg80211/mac80211 - WiFi drivers: - Qualcomm/Atheros: - ath11k: support for Channel Frequency Response measurement - ath12k: a significant driver refactor to support multi-wiphy devices and and pave the way for future device support in the same driver (rather than splitting to ath13k) - ath12k: support for the QCC2072 chipset - Intel: - iwlwifi: partial Neighbor Awareness Networking (NAN) support - iwlwifi: initial support for U-NII-9 and IEEE 802.11bn - RealTek (rtw89): - preparations for RTL8922DE support - Bluetooth: - implement setsockopt(BT_PHY) to set the connection packet type/PHY - set link_policy on incoming ACL connections - Bluetooth drivers: - btusb: add support for MediaTek7920, Realtek RTL8761BU and 8851BE - btqca: add WCN6855 firmware priority selection feature" * tag 'net-next-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1254 commits) bnge/bng_re: Add a new HSI net: macb: Fix tx/rx malfunction after phy link down and up af_unix: Fix memleak of newsk in unix_stream_connect(). net: ti: icssg-prueth: Add optional dependency on HSR net: dsa: add basic initial driver for MxL862xx switches net: mdio: add unlocked mdiodev C45 bus accessors net: dsa: add tag format for MxL862xx switches dt-bindings: net: dsa: add MaxLinear MxL862xx selftests: drivers: net: hw: Modify toeplitz.c to poll for packets octeontx2-pf: Unregister devlink on probe failure net: renesas: rswitch: fix forwarding offload statemachine ionic: Rate limit unknown xcvr type messages tcp: inet6_csk_xmit() optimization tcp: populate inet->cork.fl.u.ip6 in tcp_v6_syn_recv_sock() tcp: populate inet->cork.fl.u.ip6 in tcp_v6_connect() ipv6: inet6_csk_xmit() and inet6_csk_update_pmtu() use inet->cork.fl.u.ip6 ipv6: use inet->cork.fl.u.ip6 and np->final in ip6_datagram_dst_update() ipv6: use np->final in inet6_sk_rebuild_header() ipv6: add daddr/final storage in struct ipv6_pinfo net: stmmac: qcom-ethqos: fix qcom_ethqos_serdes_powerup() ...
2026-02-09Merge tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linuxLinus Torvalds1-0/+3
Pull documentation updates from Jonathan Corbet: "A slightly calmer cycle for docs this time around, though there is still a fair amount going on, including: - Some signs of life on the long-moribund Japanese translation - Documentation on policies around the use of generative tools for patch submissions, and a separate document intended for consumption by generative tools - The completion of the move of the documentation tools to tools/docs. For now we're leaving a /scripts/kernel-doc symlink behind to avoid breaking scripts - Ongoing build-system work includes the incorporation of documentation in Python code, better support for documenting variables, and lots of improvements and fixes - Automatic linking of man-page references -- cat(1), for example -- to the online pages in the HTML build ...and the usual array of typo fixes and such" * tag 'docs-7.0' of git://git.kernel.org/pub/scm/linux/kernel/git/docs/linux: (107 commits) doc: development-process: add notice on testing tools: sphinx-build-wrapper: improve its help message docs: sphinx-build-wrapper: allow -v override -q docs: kdoc: Fix pdfdocs build for tools docs: ja_JP: process: translate 'Obtain a current source tree' docs: fix 're-use' -> 'reuse' in documentation docs: ioctl-number: fix a typo in ioctl-number.rst docs: filesystems: ensure proc pid substitutable is complete docs: automarkup.py: Skip common English words as C identifiers Documentation: use a source-read extension for the index link boilerplate docs: parse_features: make documentation more consistent docs: add parse_features module documentation docs: jobserver: do some documentation improvements docs: add jobserver module documentation docs: kabi: helpers: add documentation for each "enum" value docs: kabi: helpers: add helper for debug bits 7 and 8 docs: kabi: system_symbols: end docstring phrases with a dot docs: python: abi_regex: do some improvements at documentation docs: python: abi_parser: do some improvements at documentation docs: add kabi modules documentation ...
2026-02-09Merge tag 'vfs-7.0-rc1.initrd' of ↵Linus Torvalds1-6/+0
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs initrd removal from Christian Brauner: "Remove the deprecated linuxrc-based initrd code path and related dead code. The linuxrc initrd path was deprecated in 2020 and this series completes its removal. If we see real-life regressions we'll revert. The core change removes handle_initrd() and init_linuxrc() — the entire flow that ran /linuxrc from an initrd, pivoted roots, and handed off to the real root filesystem. With that gone, initrd_load() becomes void (no longer short-circuits prepare_namespace()), rd_load_image() is simplified to always load /initrd.image instead of taking a path, and rd_load_disk() is deleted. The /proc/sys/kernel/real-root-dev sysctl and its backing variable are removed since they only existed for linuxrc to communicate the real root device back to the kernel. The no-op load_ramdisk= and prompt_ramdisk= parameters are dropped, and noinitrd and ramdisk_start= gain deprecation warnings. Initramfs is entirely unaffected. The non-linuxrc initrd path (root=/dev/ram0) is preserved but now carries a deprecation warning targeting January 2027 removal" * tag 'vfs-7.0-rc1.initrd' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: init: remove /proc/sys/kernel/real-root-dev initrd: remove deprecated code path (linuxrc) init: remove deprecated "load_ramdisk" and "prompt_ramdisk" command line parameters
2026-01-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-0/+2
Cross-merge networking fixes after downstream PR (net-6.19-rc8). No adjacent changes, conflicts: drivers/net/ethernet/spacemit/k1_emac.c 2c84959167d64 ("net: spacemit: Check for netif_carrier_ok() in emac_stats_update()") f66086798f91f ("net: spacemit: Remove broken flow control support") https://lore.kernel.org/aXjAqZA3iEWD_DGM@sirena.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-26Merge tag 'vfs-6.19-rc8.fixes' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: - Fix the the buggy conversion of fuse_reverse_inval_entry() introduced during the creation rework - Disallow nfs delegation requests for directories by setting simple_nosetlease() - Require an opt-in for getting readdir flag bits outside of S_DT_MASK set in d_type - Fix scheduling delayed writeback work by only scheduling when the dirty time expiry interval is non-zero and cancel the delayed work if the interval is set to zero - Use rounded_jiffies_interval for dirty time work - Check the return value of sb_set_blocksize() for romfs - Wait for batched folios to be stable in __iomap_get_folio() - Use private naming for fuse hash size - Fix the stale dentry cleanup to prevent a race that causes a UAF * tag 'vfs-6.19-rc8.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: vfs: document d_dispose_if_unused() fuse: shrink once after all buckets have been scanned fuse: clean up fuse_dentry_tree_work() fuse: add need_resched() before unlocking bucket fuse: make sure dentry is evicted if stale fuse: fix race when disposing stale dentries fuse: use private naming for fuse hash size writeback: use round_jiffies_relative for dirtytime_work iomap: wait for batched folios to be stable in __iomap_get_folio romfs: check sb_set_blocksize() return value docs: clarify that dirtytime_expire_seconds=0 disables writeback writeback: fix 100% CPU usage when dirtytime_expire_interval is 0 readdir: require opt-in for d_type flags vboxsf: don't allow delegations to be set on directories ceph: don't allow delegations to be set on directories gfs2: don't allow delegations to be set on directories 9p: don't allow delegations to be set on directories smb/client: properly disallow delegations on directories nfs: properly disallow delegation requests on directories fuse: fix conversion of fuse_reverse_inval_entry() to start_removing()
2026-01-25net: expand NETDEV_RSS_KEY_LEN to 256 bytesEric Dumazet1-6/+7
NETDEV_RSS_KEY_LEN has been set to 52 bytes in 2014, until now. Jakub suggested we bump the size to 128 bytes or more. Some drivers (like idpf) were already working around the core limit. Since this change might cause some issues in admin scripts, bump it directly to 256 in one go. tjbp26:~# cat /proc/sys/net/core/netdev_rss_key | wc -c 768 tjbp26:~# ethtool -x eth1 RX flow hash indirection table for eth1 with 32 RX ring(s): ... RSS hash key: fe:16:5b:2f:93:85:c2:c9:c1:ef:bd:60:c6:e0:2b:99:4d:bf:b7:14:c8:1e:8d:cb:31:17:51:da:55:eb:91:d9:9e:f9:89:9b:44:a1:dc:08:72:3a:b3:d6:31:86:9a:fe:02:3a:0d:eb:a1:7c:f5:a3:51:3b:08:56:c9:3f:71:69:01:ba:70:38 RSS hash function: toeplitz: on xor: off crc32: off Suggested-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/netdev/20260122075206.504ec591@kernel.org/ Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20260122190349.2771064-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-20mm, hugetlb: implement movable_gigantic_pages sysctlGregory Price1-0/+28
This reintroduces a concept removed by: commit d6cb41cc44c6 ("mm, hugetlb: remove hugepages_treat_as_movable sysctl") This sysctl provides flexibility between ZONE_MOVABLE use cases: 1) onlining memory in ZONE_MOVABLE to maintain hotplug compatibility 2) onlining memory in ZONE_MOVABLE to make hugepage allocate reliable When ZONE_MOVABLE is used to make huge page allocation more reliable, disallowing gigantic pages memory in this region is pointless. If hotplug is not a requirement, we can loosen the restrictions to allow 1GB gigantic pages in ZONE_MOVABLE. Since 1GB can be difficult to migrate / has impacts on compaction / defragmentation, we don't enable this by default. Notably, 1GB pages can only be migrated if another 1GB page is available - so hot-unplug will fail if such a page cannot be found. However, since there are scenarios where gigantic pages are migratable, we should allow use of these on movable regions. When not valid 1GB is available for migration, hot-unplug will retry indefinitely (or until interrupted). For example: echo 0 > node0/hugepages/..-1GB/nr_hugepages # clear node0 1GB pages echo 1 > node1/hugepages/..-1GB/nr_hugepages # reserve node1 1GB page ./alloc_huge_node1 & # Allocate a 1GB page on node1 ./node1_offline & # attempt to offline all node1 memory echo 1 > node0/hugepages/..-1GB/nr_hugepages # reserve node0 1GB page In this example, node1_offline will block indefinitely until the final step, when a node0 1GB page is made available. Note: Boot-time CMA is not possible for driver-managed hotplug memory, as CMA requires the memory to be registered as SystemRAM at boot time. Additionally, 1GB huge pages are not supported by THP. Link: https://lkml.kernel.org/r/20251221125603.2364174-1-gourry@gourry.net Signed-off-by: Gregory Price <gourry@gourry.net> Suggested-by: David Rientjes <rientjes@google.com> Link: https://lore.kernel.org/all/20180201193132.Hk7vI_xaU%25akpm@linux-foundation.org/ Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: "David Hildenbrand (Red Hat)" <david@kernel.org> Cc: Gregory Price <gourry@gourry.net> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Oscar Salvador <osalvador@suse.de> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20mm/block/fs: remove laptop_modeJohannes Weiner1-8/+0
Laptop mode was introduced to save battery, by delaying and consolidating writes and thereby maximize the time rotating hard drives wouldn't have to spin. Luckily, rotating hard drives, with their high spin-up times and power draw, are a thing of the past for battery-powered devices. Reclaim has also since changed to not write single filesystem pages anymore, and regular filesystem writeback is lumpy by design. The juice doesn't appear worth the squeeze anymore. The footprint of the feature is small, but nevertheless it's a complicating factor in mm, block, filesystems. Developers don't think about it, and it likely hasn't been tested with new reclaim and writeback changes in years. Let's sunset it. Keep the sysctl with a deprecation warning around for a few more cycles, but remove all functionality behind it. [akpm@linux-foundation.org: fix Documentation/admin-guide/laptops/index.rst] Link: https://lkml.kernel.org/r/20251216185201.GH905277@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Suggested-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Deepanshu Kartikey <kartikey406@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20Docs/mm/allocation-profiling: describe sysctrl limitations in debug modeSuren Baghdasaryan1-0/+4
When CONFIG_MEM_ALLOC_PROFILING_DEBUG=y, /proc/sys/vm/mem_profiling is read-only to avoid debug warnings in a scenario when an allocation is made while profiling is disabled (allocation does not get an allocation tag), then profiling gets enabled and allocation gets freed (warning due to the allocation missing allocation tag). Link: https://lkml.kernel.org/r/20260116184423.2708363-1-surenb@google.com Fixes: ebdf9ad4ca98 ("memprofiling: documentation") Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: SeongJae Park <sj@kernel.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Ran Xiaokai <ran.xiaokai@zte.com.cn> Cc: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-16docs: make kptr_restrict and hash_pointers reference each otherMarc Herbert1-0/+3
vsprintf.c uses a mix of the `kernel.kptr_restrict` sysctl and the `hash_pointers` boot param to control pointer hashing. But that wasn't