kernel/linux.git/tools/include/uapi, branch v6.19.11

treewide: Update email address

2026-01-11T16:09:11+00:00

In a vain attempt to consolidate the email zoo switch everything to the kernel.org account. Signed-off-by: Thomas Gleixner Signed-off-by: Linus Torvalds

tools headers: Sync syscall table with kernel sources

2025-12-24T19:43:36+00:00

To pick up changes from: b36d4b6aa88ef039 ("arch: hookup listns() system call") This should be used to beautify the syscall arguments and it addresses these tools/perf build warnings: Warning: Kernel ABI header differences: diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h diff -u tools/scripts/syscall.tbl scripts/syscall.tbl diff -u tools/perf/arch/x86/entry/syscalls/syscall_32.tbl arch/x86/entry/syscalls/syscall_32.tbl diff -u tools/perf/arch/x86/entry/syscalls/syscall_64.tbl arch/x86/entry/syscalls/syscall_64.tbl diff -u tools/perf/arch/powerpc/entry/syscalls/syscall.tbl arch/powerpc/kernel/syscalls/syscall.tbl diff -u tools/perf/arch/s390/entry/syscalls/syscall.tbl arch/s390/kernel/syscalls/syscall.tbl diff -u tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl arch/mips/kernel/syscalls/syscall_n64.tbl diff -u tools/perf/arch/arm/entry/syscalls/syscall.tbl arch/arm/tools/syscall.tbl diff -u tools/perf/arch/sh/entry/syscalls/syscall.tbl arch/sh/kernel/syscalls/syscall.tbl diff -u tools/perf/arch/sparc/entry/syscalls/syscall.tbl arch/sparc/kernel/syscalls/syscall.tbl diff -u tools/perf/arch/xtensa/entry/syscalls/syscall.tbl arch/xtensa/kernel/syscalls/syscall.tbl Please see tools/include/uapi/README. Note that s390 syscall table is still out of sync as it switches to use the generic table. But I'd like to minimize the change in this commit. Cc: linux-arch@vger.kernel.org Signed-off-by: Namhyung Kim

tools headers: Sync UAPI KVM headers with kernel sources

2025-12-24T19:42:13+00:00

To pick up changes from: ad9c62bd8946621e ("KVM: arm64: VM exit to userspace to handle SEA") 8e8678e740ecde2a ("KVM: s390: Add capability that forwards operation exceptions") e0c26d47def7382d ("Merge tag 'kvm-s390-next-6.19-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD") 7a61d61396b97fd6 ("KVM: SEV: Publish supported SEV-SNP policy bits") This should be used to beautify DRM syscall arguments and it addresses these tools/perf build warnings: Warning: Kernel ABI header differences: diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h Please see tools/include/uapi/README. Cc: kvm@vger.kernel.org Signed-off-by: Namhyung Kim

tools headers: Sync UAPI drm/drm.h with kernel sources

2025-12-24T19:42:00+00:00

To pick up changes from: 179ab8e7d7b378f1 ("drm/colorop: Introduce DRM_CLIENT_CAP_PLANE_COLOR_PIPELINE") This should be used to beautify DRM syscall arguments and it addresses these tools/perf build warnings: Warning: Kernel ABI header differences: diff -u tools/include/uapi/drm/drm.h include/uapi/drm/drm.h Please see tools/include/uapi/README. Cc: dri-devel@lists.freedesktop.org Signed-off-by: Namhyung Kim

Merge tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools

2025-12-07T15:07:02+00:00

Pull perf tools updates from Namhyung Kim: "Perf event/metric description: Unify all event and metric descriptions in JSON format. Now event parsing and handling is greatly simplified by that. From users point of view, perf list will provide richer information about hardware events like the following. $ perf list hw List of pre-defined events (to be used in -e or -M): legacy hardware: branch-instructions [Retired branch instructions [This event is an alias of branches]. Unit: cpu] branch-misses [Mispredicted branch instructions. Unit: cpu] branches [Retired branch instructions [This event is an alias of branch-instructions]. Unit: cpu] bus-cycles [Bus cycles,which can be different from total cycles. Unit: cpu] cache-misses [Cache misses. Usually this indicates Last Level Cache misses; this is intended to be used in conjunction with the PERF_COUNT_HW_CACHE_REFERENCES event to calculate cache miss rates. Unit: cpu] cache-references [Cache accesses. Usually this indicates Last Level Cache accesses but this may vary depending on your CPU. This may include prefetches and coherency messages; again this depends on the design of your CPU. Unit: cpu] cpu-cycles [Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cycles]. Unit: cpu] cycles [Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cpu-cycles]. Unit: cpu] instructions [Retired instructions. Be careful,these can be affected by various issues,most notably hardware interrupt counts. Unit: cpu] ref-cycles [Total cycles; not affected by CPU frequency scaling. Unit: cpu] But most notable changes would be in the perf stat. On the right side, the default metrics are better named and aligned. :) $ perf stat -- perf test -w noploop Performance counter stats for 'perf test -w noploop': 11 context-switches # 10.8 cs/sec cs_per_second 0 cpu-migrations # 0.0 migrations/sec migrations_per_second 3,612 page-faults # 3532.5 faults/sec page_faults_per_second 1,022.51 msec task-clock # 1.0 CPUs CPUs_utilized 110,466 branch-misses # 0.0 % branch_miss_rate (88.66%) 6,934,452,104 branches # 6781.8 M/sec branch_frequency (88.66%) 4,657,032,590 cpu-cycles # 4.6 GHz cycles_frequency (88.65%) 27,755,874,218 instructions # 6.0 instructions insn_per_cycle (89.03%) TopdownL1 # 0.3 % tma_backend_bound # 9.3 % tma_bad_speculation (89.05%) # 9.7 % tma_frontend_bound (77.86%) # 80.7 % tma_retiring (88.81%) 1.025318171 seconds time elapsed 1.013248000 seconds user 0.012014000 seconds sys Deferred unwinding support: With the kernel support (commit c69993ecdd4d: "perf: Support deferred user unwind"), perf can use deferred callchains for userspace stack trace with frame pointers like below: $ perf record --call-graph fp,defer ... This will be transparent to users when it comes to other commands like perf report and perf script. They will merge the deferred callchains to the previous samples as if they were collected together. ARM SPE updates - Extensive enhancements to support various kinds of memory operations including GCS, MTE allocation tags, memcpy/memset, register access, and SIMD operations. - Add inverted data source filter (inv_data_src_filter) support to exclude certain data sources. - Improve documentation. Vendor event updates: - Intel: Updated event files for Sierra Forest, Panther Lake, Meteor Lake, Lunar Lake, Granite Rapids, and others. - Arm64: Added metrics for i.MX94 DDR PMU and Cortex-A720AE definitions. - RISC-V: Added JSON support for T-HEAD C920V2. Misc: - Improve pointer tracking in data type profiling. It'd give better output when the variable is using container_of() to convert type. - Annotation support for perf c2c report in TUI. Press 'a' key to enter annotation view from cacheline browser window. This will show which instruction is causing the cacheline contention. - Lots of fixes and test coverage improvements!" * tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (214 commits) libperf: Use 'extern' in LIBPERF_API visibility macro perf stat: Improve handling of termination by signal perf tests stat: Add test for error for an offline CPU perf stat: When no events, don't report an error if there is none perf tests stat: Add "--null" coverage perf cpumap: Add "any" CPU handling to cpu_map__snprint_mask libperf cpumap: Fix perf_cpu_map__max for an empty/NULL map perf stat: Allow no events to open if this is a "--null" run perf test kvm: Add some basic perf kvm test coverage perf tests evlist: Add basic evlist test perf tests script dlfilter: Add a dlfilter test perf tests kallsyms: Add basic kallsyms test perf tests timechart: Add a perf timechart test perf tests top: Add basic perf top coverage test perf tests buildid: Add purge and remove testing perf tests c2c: Add a basic c2c perf c2c: Clean up some defensive gets and make asan clean perf jitdump: Fix missed dso__put perf mem-events: Don't leak online CPU map perf hist: In init, ensure mem_info is put on error paths ...

Merge tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2025-12-04T01:24:33+00:00

Pull networking updates from Jakub Kicinski: "Core & protocols: - Replace busylock at the Tx queuing layer with a lockless list. Resulting in a 300% (4x) improvement on heavy TX workloads, sending twice the number of packets per second, for half the cpu cycles. - Allow constantly busy flows to migrate to a more suitable CPU/NIC queue. Normally we perform queue re-selection when flow comes out of idle, but under extreme circumstances the flows may be constantly busy. Add sysctl to allow periodic rehashing even if it'd risk packet reordering. - Optimize the NAPI skb cache, make it larger, use it in more paths. - Attempt returning Tx skbs to the originating CPU (like we already did for Rx skbs). - Various data structure layout and prefetch optimizations from Eric. - Remove ktime_get() from the recvmsg() fast path, ktime_get() is sadly quite expensive on recent AMD machines. - Extend threaded NAPI polling to allow the kthread busy poll for packets. - Make MPTCP use Rx backlog processing. This lowers the lock pressure, improving the Rx performance. - Support memcg accounting of MPTCP socket memory. - Allow admin to opt sockets out of global protocol memory accounting (using a sysctl or BPF-based policy). The global limits are a poor fit for modern container workloads, where limits are imposed using cgroups. - Improve heuristics for when to kick off AF_UNIX garbage collection. - Allow users to control TCP SACK compression, and default to 33% of RTT. - Add tcp_rcvbuf_low_rtt sysctl to let datacenter users avoid unnecessarily aggressive rcvbuf growth and overshot when the connection RTT is low. - Preserve skb metadata space across skb_push / skb_pull operations. - Support for IPIP encapsulation in the nftables flowtable offload. - Support appending IP interface information to ICMP messages (RFC 5837). - Support setting max record size in TLS (RFC 8449). - Remove taking rtnl_lock from RTM_GETNEIGHTBL and RTM_SETNEIGHTBL. - Use a dedicated lock (and RCU) in MPLS, instead of rtnl_lock. - Let users configure the number of write buffers in SMC. - Add new struct sockaddr_unsized for sockaddr of unknown length, from Kees. - Some conversions away from the crypto_ahash API, from Eric Biggers. - Some preparations for slimming down struct page. - YAML Netlink protocol spec for WireGuard. - Add a tool on top of YAML Netlink specs/lib for reporting commonly computed derived statistics and summarized system state. Driver API: - Add CAN XL support to the CAN Netlink interface. - Add uAPI for reporting PHY Mean Square Error (MSE) diagnostics, as defined by the OPEN Alliance's "Advanced diagnostic features for 100BASE-T1 automotive Ethernet PHYs" specification. - Add DPLL phase-adjust-gran pin attribute (and implement it in zl3073x). - Refactor xfrm_input lock to reduce contention when NIC offloads IPsec and performs RSS. - Add info to devlink params whether the current setting is the default or a user override. Allow resetting back to default. - Add standard device stats for PSP crypto offload. - Leverage DSA frame broadcast to implement simple HSR frame duplication for a lot of switches without dedicated HSR offload. - Add uAPI defines for 1.6Tbps link modes. Device drivers: - Add Motorcomm YT921x gigabit Ethernet switch support. - Add MUCSE driver for N500/N210 1GbE NIC series. - Convert drivers to support dedicated ops for timestamping control, and away from the direct IOCTL handling. While at it support GET operations for PHY timestamping. - Add (and convert most drivers to) a dedicated ethtool callback for reading the Rx ring count. - Significant refactoring efforts in the STMMAC driver, which supports Synopsys turn-key MAC IP integrated into a ton of SoCs. - Ethernet high-speed NICs: - Broadcom (bnxt): - support PPS in/out on all pins - Intel (100G, ice, idpf): - ice: implement standard ethtool and timestamping stats - i40e: support setting the max number of MAC addresses per VF - iavf: support RSS of GTP tunnels for 5G and LTE deployments - nVidia/Mellanox (mlx5): - reduce downtime on interface reconfiguration - disable being an XDP redirect target by default (same as other drivers) to avoid wasting resources if feature is unused - Meta (fbnic): - add support for Linux-managed PCS on 25G, 50G, and 100G links - Wangxun: - support Rx descriptor merge, and Tx head writeback - support Rx coalescing offload - support 25G SPF and 40G QSFP modules - Ethernet virtual: - Google (gve): - allow ethtool to configure rx_buf_len - implement XDP HW RX Timestamping support for DQ descriptor format - Microsoft vNIC (mana): - support HW link state events - handle hardware recovery events when probing the device - Ethernet NICs consumer, and embedded: - usbnet: add support for Byte Queue Limits (BQL) - AMD (amd-xgbe): - add device selftests - NXP (enetc): - add i.MX94 support - Broadcom integrated MACs (bcmgenet, bcmasp): - bcmasp: add support for PHY-based Wake-on-LAN - Broadcom switches (b53): - support port isolation - support BCM5389/97/98 and BCM63XX ARL formats - Lantiq/MaxLinear switches: - support bridge FDB entries on the CPU port - use regmap for register access - allow user to enable/disable learning - support Energy Efficient Ethernet - support configuring RMII clock delays - add tagging driver for MaxLinear GSW1xx switches - Synopsys (stmmac): - support using the HW clock in free running mode - add Eswin EIC7700 support - add Rockchip RK3506 support - add Altera Agilex5 support - Cadence (macb): - cleanup and consolidate descriptor and DMA address handling - add EyeQ5 support - TI: - icssg-prueth: support AF_XDP - Airoha access points: - add missing Ethernet stats and link state callback - add AN7583 support - support out-of-order Tx completion processing - Power over Ethernet: - pd692x0: preserve PSE configuration across reboots - add support for TPS23881B devices - Ethernet PHYs: - Open Alliance OATC14 10BASE-T1S PHY cable diagnostic support - Support 50G SerDes and 100G interfaces in Linux-managed PHYs - micrel: - support for non PTP SKUs of lan8814 - enable in-band auto-negotiation on lan8814 - realtek: - cable testing support on RTL8224 - interrupt support on RTL8221B - motorcomm: support for PHY LEDs on YT853 - microchip: support for LAN867X Rev.D0 PHYs w/ SQI and cable diag - mscc: support for PHY LED control - CAN drivers: - m_can: add support for optional reset and system wake up - remove can_change_mtu() obsoleted by core handling - mcp251xfd: support GPIO controller functionality - Bluetooth: - add initial support for PASTa - WiFi: - split ieee80211.h file, it's way too big - improvements in VHT radiotap reporting, S1G, Channel Switch Announcement handling, rate tracking in mesh networks - improve multi-radio monitor mode support, and add a cfg80211 debugfs interface for it - HT action frame handling on 6 GHz - initial chanctx work towards NAN - MU-MIMO sniffer improvements - WiFi drivers: - RealTek (rtw89): - support USB devices RTL8852AU and RTL8852CU - initial work for RTL8922DE - improved injection support - Intel: - iwlwifi: new sniffer API support - MediaTek (mt76): - WED support for >32-bit DMA - airoha NPU support - regdomain improvements - continued WiFi7/MLO work - Qualcomm/Atheros: - ath10k: factory test support - ath11k: TX power insertion support - ath12k: BSS color change support - ath12k: statistics improvements - brcmfmac: Acer A1 840 tablet quirk - rtl8xxxu: 40 MHz connection fixes/support" * tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1381 commits) net: page_pool: sanitise allocation order net: page pool: xa init with destroy on pp init net/mlx5e: Support XDP target xmit with dummy program net/mlx5e: Update XDP features in switch channels selftests/tc-testing: Test CAKE scheduler when enqueue drops packets net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop wireguard: netlink: generate netlink code wireguard: uapi: generate header with ynl-gen wireguard: uapi: move flag enums wireguard: uapi: move enum wg_cmd wireguard: netlink: add YNL specification selftests: drv-net: Fix tolerance calculation in devlink_rate_tc_bw.py selftests: drv-net: Fix and clarify TC bandwidth split in devlink_rate_tc_bw.py selftests: drv-net: Set shell=True for sysfs writes in devlink_rate_tc_bw.py selftests: drv-net: Use Iperf3Runner in devlink_rate_tc_bw.py selftests: drv-net: introduce Iperf3Runner for measurement use cases selftests: drv-net: Add devlink_rate_tc_bw.py to TEST_PROGS net: ps3_gelic_net: Use napi_alloc_skb() and napi_gro_receive() Documentation: net: dsa: mention simple HSR offload helpers Documentation: net: dsa: mention availability of RedBox ...

Merge tag 'bpf-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2025-12-04T00:54:54+00:00

Pull bpf updates from Alexei Starovoitov: - Convert selftests/bpf/test_tc_edt and test_tc_tunnel from .sh to test_progs runner (Alexis Lothoré) - Convert selftests/bpf/test_xsk to test_progs runner (Bastien Curutchet) - Replace bpf memory allocator with kmalloc_nolock() in bpf_local_storage (Amery Hung), and in bpf streams and range tree (Puranjay Mohan) - Introduce support for indirect jumps in BPF verifier and x86 JIT (Anton Protopopov) and arm64 JIT (Puranjay Mohan) - Remove runqslower bpf tool (Hoyeon Lee) - Fix corner cases in the verifier to close several syzbot reports (Eduard Zingerman, KaFai Wan) - Several improvements in deadlock detection in rqspinlock (Kumar Kartikeya Dwivedi) - Implement "jmp" mode for BPF trampoline and corresponding DYNAMIC_FTRACE_WITH_JMP. It improves "fexit" program type performance from 80 M/s to 136 M/s. With Steven's Ack. (Menglong Dong) - Add ability to test non-linear skbs in BPF_PROG_TEST_RUN (Paul Chaignon) - Do not let BPF_PROG_TEST_RUN emit invalid GSO types to stack (Daniel Borkmann) - Generalize buildid reader into bpf_dynptr (Mykyta Yatsenko) - Optimize bpf_map_update_elem() for map-in-map types (Ritesh Oedayrajsingh Varma) - Introduce overwrite mode for BPF ring buffer (Xu Kuohai) * tag 'bpf-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (169 commits) bpf: optimize bpf_map_update_elem() for map-in-map types bpf: make kprobe_multi_link_prog_run always_inline selftests/bpf: do not hardcode target rate in test_tc_edt BPF program selftests/bpf: remove test_tc_edt.sh selftests/bpf: integrate test_tc_edt into test_progs selftests/bpf: rename test_tc_edt.bpf.c section to expose program type selftests/bpf: Add success stats to rqspinlock stress test rqspinlock: Precede non-head waiter queueing with AA check rqspinlock: Disable spinning for trylock fallback rqspinlock: Use trylock fallback when per-CPU rqnode is busy rqspinlock: Perform AA checks immediately rqspinlock: Enclose lock/unlock within lock entry acquisitions bpf: Remove runqslower tool selftests/bpf: Remove usage of lsm/file_alloc_security in selftest bpf: Disable file_alloc_security hook bpf: check for insn arrays in check_ptr_alignment bpf: force BPF_F_RDONLY_PROG on insn array creation bpf: Fix exclusive map memory leak selftests/bpf: Make CS length configurable for rqspinlock stress test selftests/bpf: Add lock wait time stats to rqspinlock stress test ...

tools headers UAPI: Sync linux/perf_event.h for deferred callchains

2025-12-03T00:13:32+00:00

It needs to sync with the kernel to support user space changes for the deferred callchains. Reviewed-by: Ian Rogers Signed-off-by: Namhyung Kim

Merge tag 'perf-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T04:42:01+00:00

Pull performance events updates from Ingo Molnar: "Callchain support: - Add support for deferred user-space stack unwinding for perf, enabled on x86. (Peter Zijlstra, Steven Rostedt) - unwind_user/x86: Enable frame pointer unwinding on x86 (Josh Poimboeuf) x86 PMU support and infrastructure: - x86/insn: Simplify for_each_insn_prefix() (Peter Zijlstra) - x86/insn,uprobes,alternative: Unify insn_is_nop() (Peter Zijlstra) Intel PMU driver: - Large series to prepare for and implement architectural PEBS support for Intel platforms such as Clearwater Forest (CWF) and Panther Lake (PTL). (Dapeng Mi, Kan Liang) - Check dynamic constraints (Kan Liang) - Optimize PEBS extended config (Peter Zijlstra) - cstates: - Remove PC3 support from LunarLake (Zhang Rui) - Add Pantherlake support (Zhang Rui) - Clearwater Forest support (Zide Chen) AMD PMU driver: - x86/amd: Check event before enable to avoid GPF (George Kennedy) Fixes and cleanups: - task_work: Fix NMI race condition (Peter Zijlstra) - perf/x86: Fix NULL event access and potential PEBS record loss (Dapeng Mi) - Misc other fixes and cleanups (Dapeng Mi, Ingo Molnar, Peter Zijlstra)" * tag 'perf-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits) perf/x86/intel: Fix and clean up intel_pmu_drain_arch_pebs() type use perf/x86/intel: Optimize PEBS extended config perf/x86/intel: Check PEBS dyn_constraints perf/x86/intel: Add a check for dynamic constraints perf/x86/intel: Add counter group support for arch-PEBS perf/x86/intel: Setup PEBS data configuration and enable legacy groups perf/x86/intel: Update dyn_constraint base on PEBS event precise level perf/x86/intel: Allocate arch-PEBS buffer and initialize PEBS_BASE MSR perf/x86/intel: Process arch-PEBS records or record fragments perf/x86/intel/ds: Factor out PEBS group processing code to functions perf/x86/intel/ds: Factor out PEBS record processing code to functions perf/x86/intel: Initialize architectural PEBS perf/x86/intel: Correct large PEBS flag check perf/x86/intel: Replace x86_pmu.drain_pebs calling with static call perf/x86: Fix NULL event access and potential PEBS record loss perf/x86: Remove redundant is_x86_event() prototype entry,unwind/deferred: Fix unwind_reset_info() placement unwind_user/x86: Fix arch=um build perf: Support deferred user unwind unwind_user/x86: Teach FP unwind about start of function ...

Merge tag 'namespace-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-01T17:47:41+00:00

Pull namespace updates from Christian Brauner: "This contains substantial namespace infrastructure changes including a new system call, active reference counting, and extensive header cleanups. The branch depends on the shared kbuild branch for -fms-extensions support. Features: - listns() system call Add a new listns() system call that allows userspace to iterate through namespaces in the system. This provides a programmatic interface to discover and inspect namespaces, addressing longstanding limitations: Currently, there is no direct way for userspace to enumerate namespaces. Applications must resort to scanning /proc/*/ns/ across all processes, which is: - Inefficient - requires iterating over all processes - Incomplete - misses namespaces not attached to any running process but kept alive by file descriptors, bind mounts, or parent references - Permission-heavy - requires access to /proc for many processes - No ordering or ownership information - No filtering per namespace type The listns() system call solves these problems: ssize_t listns(const struct ns_id_req *req, u64 *ns_ids, size_t nr_ns_ids, unsigned int flags); struct ns_id_req { __u32 size; __u32 spare; __u64 ns_id; struct /* listns */ { __u32 ns_type; __u32 spare2; __u64 user_ns_id; }; }; Features include: - Pagination support for large namespace sets - Filtering by namespace type (MNT_NS, NET_NS, USER_NS, etc.) - Filtering by owning user namespace - Permission checks respecting namespace isolation - Active Reference Counting Introduce an active reference count that tracks namespace visibility to userspace. A namespace is visible in the following cases: - The namespace is in use by a task - The namespace is persisted through a VFS object (namespace file descriptor or bind-mount) - The namespace is a hierarchical type and is the parent of child namespaces The active reference count does not regulate lifetime (that's still done by the normal reference count) - it only regulates visibility to namespace file handles and listns(). This prevents resurrection of namespaces that are pinned only for internal kernel reasons (e.g., user namespaces held by file->f_cred, lazy TLB references on idle CPUs, etc.) which should not be accessible via (1)-(3). - Unified Namespace Tree Introduce a unified tree structure for all namespaces with: - Fixed IDs assigned to initial namespaces - Lookup based solely on inode number - Maintained list of owned namespaces per user namespace - Simplified rbtree comparison helpers Cleanups - Header Reorganization: - Move namespace types into separate header (ns_common_types.h) - Decouple nstree from ns_common header - Move nstree types into separate header - Switch to new ns_tree_{node,root} structures with helper functions - Use guards for ns_tree_lock - Initial Namespace Reference Count Optimization - Make all reference counts on initial namespaces a nop to avoid pointless cacheline ping-pong for namespaces that can never go away - Drop custom reference count initialization for initial namespaces - Add NS_COMMON_INIT() macro and use it for all namespaces - pid: rely on common reference count behavior - Miscellaneous Cleanups - Rename exit_task_namespaces() to exit_nsproxy_namespaces() - Rename is_initial_namespace() and make argument const - Use boolean to indicate anonymous mount namespace - Simplify owner list iteration in nstree - nsfs: raise SB_I_NODEV, SB_I_NOEXEC, and DCACHE_DONTCACHE explicitly - nsfs: use inode_just_drop() - pidfs: raise DCACHE_DONTCACHE explicitly - pidfs: simplify PIDFD_GET__NAMESPACE ioctls - libfs: allow to specify s_d_flags - cgroup: add cgroup namespace to tree after owner is set - nsproxy: fix free_nsproxy() and simplify create_new_namespaces() Fixes: - setns(pidfd, ...) race condition Fix a subtle race when using pidfds with setns(). When the target task exits after prepare_nsset() but before commit_nsset(), the namespace's active reference count might have been dropped. If setns() then installs the namespaces, it would bump the active reference count from zero without taking the required reference on the owner namespace, leading to underflow when later decremented. The fix resurrects the ownership chain if necessary - if the caller succeeded in grabbing passive references, the setns() should succeed even if the target task exits or gets reaped. - Return EFAULT on put_user() error instead of success - Make sure references are dropped outside of RCU lock (some namespaces like mount namespace sleep when putting the last reference) - Don't skip active reference count initialization for network namespace - Add asserts for active refcount underflow - Add asserts for initial namespace reference counts (both passive and active) - ipc: enable is_ns_init_id() assertions - Fix kernel-doc comments for internal nstree functions - Selftests - 15 active reference count tests - 9 listns() functionality tests - 7 listns() permission tests - 12 inactive namespace resurrection tests - 3 threaded active reference count tests - commit_creds() active reference tests - Pagination and stress tests - EFAULT handling test - nsid tests fixes" * tag 'namespace-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (103 commits) pidfs: simplify PIDFD_GET__NAMESPACE ioctls nstree: fix kernel-doc comments for internal functions nsproxy: fix free_nsproxy() and simplify create_new_namespaces() selftests/namespaces: fix nsid tests ns: drop custom reference count initialization for initial namespaces pid: rely on common reference count behavior ns: add asserts for initial namespace active reference counts ns: add asserts for initial namespace reference counts ns: make all reference counts on initial namespace a nop ipc: enable is_ns_init_id() assertions fs: use boolean to indicate anonymous mount namespace ns: rename is_initial_namespace() ns: make is_initial_namespace() argument const nstree: use guards for ns_tree_lock nstree: simplify owner list iteration nstree: switch to new structures nstree: add helper to operate on struct ns_tree_{node,root} nstree: move nstree types into separate header nstree: decouple from ns_common header ns: move namespace types into separate header ...