Pull hyperv updates from Wei Liu:
- Enhancements to Linux as the root partition for Microsoft Hypervisor:
- Support a new mode called L1VH, which allows Linux to drive the
hypervisor running the Azure Host directly
- Support for MSHV crash dump collection
- Allow Linux's memory management subsystem to better manage guest
memory regions
- Fix issues that prevented a clean shutdown of the whole system on
bare metal and nested configurations
- ARM64 support for the MSHV driver
- Various other bug fixes and cleanups
- Add support for Confidential VMBus for Linux guest on Hyper-V
- Secure AVIC support for Linux guests on Hyper-V
- Add the mshv_vtl driver to allow Linux to run as the secure kernel in
a higher virtual trust level for Hyper-V
* tag 'hyperv-next-signed-20251207' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux: (58 commits)
mshv: Cleanly shutdown root partition with MSHV
mshv: Use reboot notifier to configure sleep state
mshv: Add definitions for MSHV sleep state configuration
mshv: Add support for movable memory regions
mshv: Add refcount and locking to mem regions
mshv: Fix huge page handling in memory region traversal
mshv: Move region management to mshv_regions.c
mshv: Centralize guest memory region destruction
mshv: Refactor and rename memory region handling functions
mshv: adjust interrupt control structure for ARM64
Drivers: hv: use kmalloc_array() instead of kmalloc()
mshv: Add ioctl for self targeted passthrough hvcalls
Drivers: hv: Introduce mshv_vtl driver
Drivers: hv: Export some symbols for mshv_vtl
static_call: allow using STATIC_CALL_TRAMP_STR() from assembly
mshv: Extend create partition ioctl to support cpu features
mshv: Allow mappings that overlap in uaddr
mshv: Fix create memory region overlap check
mshv: add WQ_PERCPU to alloc_workqueue users
Drivers: hv: Use kmalloc_array() instead of kmalloc()
...
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 c69993ecdd: "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
...
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
...
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
...
Pull nolibc updates from Thomas Weißschuh:
- Preparations to the use of nolibc in UML:
- Cleanup of sparse warnings
- Library mode without _start()
- More consistency when disabling errno
- Unconditional installation of all architecture support files
- Always 64-bit wide ino_t and off_t
- Various cleanups and bug fixes
* tag 'nolibc-20251130-for-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/nolibc/linux-nolibc: (25 commits)
selftests/nolibc: error out on linker warnings
selftests/nolibc: use lld to link loongarch binaries
tools/nolibc: remove more __nolibc_enosys() fallbacks
tools/nolibc: remove now superfluous overflow check in llseek
tools/nolibc: use 64-bit off_t
tools/nolibc: prefer the llseek syscall
tools/nolibc: handle 64-bit off_t for llseek
tools/nolibc: use 64-bit ino_t
tools/nolibc: avoid using plain integer as NULL pointer
tools/nolibc: add support for fchdir()
tools/nolibc: clean up outdated comments in generic arch.h
tools/nolibc: make the "headers" target install all supported archs
tools/nolibc: add the more portable inttypes.h
tools/nolibc: provide the portable sys/select.h
tools/nolibc: add missing memchr() to string.h
tools/nolibc: fix misleading help message regarding installation path
tools/nolibc: add uio.h with readv and writev
tools/nolibc: add option to disable runtime
tools/nolibc: use __fallthrough__ rather than fallthrough
tools/nolibc: implement %m if errno is not defined
...
Pull s390 updates from Heiko Carstens:
- Provide a new interface for dynamic configuration and deconfiguration
of hotplug memory, allowing with and without memmap_on_memory
support. This makes the way memory hotplug is handled on s390 much
more similar to other architectures
- Remove compat support. There shouldn't be any compat user space
around anymore, therefore get rid of a lot of code which also doesn't
need to be tested anymore
- Add stackprotector support. GCC 16 will get new compiler options,
which allow to generate code required for kernel stackprotector
support
- Merge pai_crypto and pai_ext PMU drivers into a new driver. This
removes a lot of duplicated code. The new driver is also extendable
and allows to support new PMUs
- Add driver override support for AP queues
- Rework and extend zcrypt and AP trace events to allow for tracing of
crypto requests
- Support block sizes larger than 65535 bytes for CCW tape devices
- Since the rework of the virtual kernel address space the module area
and the kernel image are within the same 4GB area. This eliminates
the need of weak per cpu variables. Get rid of
ARCH_MODULE_NEEDS_WEAK_PER_CPU
- Various other small improvements and fixes
* tag 's390-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (92 commits)
watchdog: diag288_wdt: Remove KMSG_COMPONENT macro
s390/entry: Use lay instead of aghik
s390/vdso: Get rid of -m64 flag handling
s390/vdso: Rename vdso64 to vdso
s390: Rename head64.S to head.S
s390/vdso: Use common STABS_DEBUG and DWARF_DEBUG macros
s390: Add stackprotector support
s390/modules: Simplify module_finalize() slightly
s390: Remove KMSG_COMPONENT macro
s390/percpu: Get rid of ARCH_MODULE_NEEDS_WEAK_PER_CPU
s390/ap: Restrict driver_override versus apmask and aqmask use
s390/ap: Rename mutex ap_perms_mutex to ap_attr_mutex
s390/ap: Support driver_override for AP queue devices
s390/ap: Use all-bits-one apmask/aqmask for vfio in_use() checks
s390/debug: Update description of resize operation
s390/syscalls: Switch to generic system call table generation
s390/syscalls: Remove system call table pointer from thread_struct
s390/uapi: Remove 31 bit support from uapi header files
s390: Remove compat support
tools: Remove s390 compat support
...
It needs to sync with the kernel to support user space changes for the
deferred callchains.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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
...
Pull objtool updates from Ingo Molnar:
- klp-build livepatch module generation (Josh Poimboeuf)
Introduce new objtool features and a klp-build script to generate
livepatch modules using a source .patch as input.
This builds on concepts from the longstanding out-of-tree kpatch
project which began in 2012 and has been used for many years to
generate livepatch modules for production kernels. However, this is a
complete rewrite which incorporates hard-earned lessons from 12+
years of maintaining kpatch.
Key improvements compared to kpatch-build:
- Integrated with objtool: Leverages objtool's existing control-flow
graph analysis to help detect changed functions.
- Works on vmlinux.o: Supports late-linked objects, making it
compatible with LTO, IBT, and similar.
- Simplified code base: ~3k fewer lines of code.
- Upstream: No more out-of-tree #ifdef hacks, far less cruft.
- Cleaner internals: Vastly simplified logic for
symbol/section/reloc inclusion and special section extraction.
- Robust __LINE__ macro handling: Avoids false positive binary diffs
caused by the __LINE__ macro by introducing a fix-patch-lines
script which injects #line directives into the source .patch to
preserve the original line numbers at compile time.
- Disassemble code with libopcodes instead of running objdump
(Alexandre Chartre)
- Disassemble support (-d option to objtool) by Alexandre Chartre,
which supports the decoding of various Linux kernel code generation
specials such as alternatives:
17ef: sched_balance_find_dst_group+0x62f mov 0x34(%r9),%edx
17f3: sched_balance_find_dst_group+0x633 | <alternative.17f3> | X86_FEATURE_POPCNT
17f3: sched_balance_find_dst_group+0x633 | call 0x17f8 <__sw_hweight64> | popcnt %rdi,%rax
17f8: sched_balance_find_dst_group+0x638 cmp %eax,%edx
... jump table alternatives:
1895: sched_use_asym_prio+0x5 test $0x8,%ch
1898: sched_use_asym_prio+0x8 je 0x18a9 <sched_use_asym_prio+0x19>
189a: sched_use_asym_prio+0xa | <jump_table.189a> | JUMP
189a: sched_use_asym_prio+0xa | jmp 0x18ae <sched_use_asym_prio+0x1e> | nop2
189c: sched_use_asym_prio+0xc mov $0x1,%eax
18a1: sched_use_asym_prio+0x11 and $0x80,%ecx
... exception table alternatives:
native_read_msr:
5b80: native_read_msr+0x0 mov %edi,%ecx
5b82: native_read_msr+0x2 | <ex_table.5b82> | EXCEPTION
5b82: native_read_msr+0x2 | rdmsr | resume at 0x5b84 <native_read_msr+0x4>
5b84: native_read_msr+0x4 shl $0x20,%rdx
.... x86 feature flag decoding (also see the X86_FEATURE_POPCNT
example in sched_balance_find_dst_group() above):
2faaf: start_thread_common.constprop.0+0x1f jne 0x2fba4 <start_thread_common.constprop.0+0x114>
2fab5: start_thread_common.constprop.0+0x25 | <alternative.2fab5> | X86_FEATURE_ALWAYS | X86_BUG_NULL_SEG
2fab5: start_thread_common.constprop.0+0x25 | jmp 0x2faba <.altinstr_aux+0x2f4> | jmp 0x4b0 <start_thread_common.constprop.0+0x3f> | nop5
2faba: start_thread_common.constprop.0+0x2a mov $0x2b,%eax
... NOP sequence shortening:
1048e2: snapshot_write_finalize+0xc2 je 0x104917 <snapshot_write_finalize+0xf7>
1048e4: snapshot_write_finalize+0xc4 nop6
1048ea: snapshot_write_finalize+0xca nop11
1048f5: snapshot_write_finalize+0xd5 nop11
104900: snapshot_write_finalize+0xe0 mov %rax,%rcx
104903: snapshot_write_finalize+0xe3 mov 0x10(%rdx),%rax
... and much more.
- Function validation tracing support (Alexandre Chartre)
- Various -ffunction-sections fixes (Josh Poimboeuf)
- Clang AutoFDO (Automated Feedback-Directed Optimizations) support
(Josh Poimboeuf)
- Misc fixes and cleanups (Borislav Petkov, Chen Ni, Dylan Hatch, Ingo
Molnar, John Wang, Josh Poimboeuf, Pankaj Raghav, Peter Zijlstra,
Thorsten Blum)
* tag 'objtool-core-2025-12-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (129 commits)
objtool: Fix segfault on unknown alternatives
objtool: Build with disassembly can fail when including bdf.h
objtool: Trim trailing NOPs in alternative
objtool: Add wide output for disassembly
objtool: Compact output for alternatives with one instruction
objtool: Improve naming of group alternatives
objtool: Add Function to get the name of a CPU feature
objtool: Provide access to feature and flags of group alternatives
objtool: Fix address references in alternatives
objtool: Disassemble jump table alternatives
objtool: Disassemble exception table alternatives
objtool: Print addresses with alternative instructions
objtool: Disassemble group alternatives
objtool: Print headers for alternatives
objtool: Preserve alternatives order
objtool: Add the --disas=<function-pattern> action
objtool: Do not validate IBT for .return_sites and .call_sites
objtool: Improve tracing of alternative instructions
objtool: Add functions to better name alternatives
objtool: Identify the different types of alternatives
...
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_<type>_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
...
Commit e6366101ce ("tools/nolibc: remove __nolibc_enosys() fallback
from time64-related functions") removed many of these fallbacks but
forgot a few.
Finish the job.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
As off_t is now always 64-bit wide this overflow can not happen anymore,
remove the check.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Make sure to always use the 64-bit safe system call
in preparation for 64-bit off_t on 32 bit architectures.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Remove s390 compat support from everything within tools, since s390 compat
support will be removed from the kernel.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Weißschuh <linux@weissschuh.net> # tools/nolibc selftests/nolibc
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> # selftests/vDSO
Acked-by: Alexei Starovoitov <ast@kernel.org> # bpf bits
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
STATIC_CALL_TRAMP_STR() could not be used from .S files because
static_call_types.h was not safe to include in assembly as it pulled in C
types/constructs that are unavailable under __ASSEMBLY__.
Make the header assembly-friendly by adding __ASSEMBLY__ checks and
providing only the minimal definitions needed for assembly, so that it
can be safely included by .S code. This enables emitting the static call
trampoline symbol name via STATIC_CALL_TRAMP_STR() directly in assembly
sources, to be used with 'call' instruction. Also, move a certain
definitions out of __ASSEMBLY__ checks in compiler_types.h to meet
the dependencies.
No functional change for C compilation.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.18-rc6).
No conflicts, adjacent changes in:
drivers/net/phy/micrel.c
96a9178a29 ("net: phy: micrel: lan8814 fix reset of the QSGMII interface")
61b7ade9ba ("net: phy: micrel: Add support for non PTP SKUs for lan8814")
and a trivial one in tools/testing/selftests/drivers/net/Makefile.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On bpf(BPF_PROG_LOAD) syscall user-supplied BPF programs are
translated by the verifier into "xlated" BPF programs. During this
process the original instructions offsets might be adjusted and/or
individual instructions might be replaced by new sets of instructions,
or deleted.
Add a new BPF map type which is aimed to keep track of how, for a
given program, the original instructions were relocated during the
verification. Also, besides keeping track of the original -> xlated
mapping, make x86 JIT to build the xlated -> jitted mapping for every
instruction listed in an instruction array. This is required for every
future application of instruction arrays: static keys, indirect jumps
and indirect calls.
A map of the BPF_MAP_TYPE_INSN_ARRAY type must be created with a u32
keys and value of size 8. The values have different semantics for
userspace and for BPF space. For userspace a value consists of two
u32 values – xlated and jitted offsets. For BPF side the value is
a real pointer to a jitted instruction.
On map creation/initialization, before loading the program, each
element of the map should be initialized to point to an instruction
offset within the program. Before the program load such maps should
be made frozen. After the program verification xlated and jitted
offsets can be read via the bpf(2) syscall.
If a tracked instruction is removed by the verifier, then the xlated
offset is set to (u32)-1 which is considered to be too big for a valid
BPF program offset.
One such a map can, obviously, be used to track one and only one BPF
program. If the verification process was unsuccessful, then the same
map can be re-used to verify the program with a different log level.
However, if the program was loaded fine, then such a map, being
frozen in any case, can't be reused by other programs even after the
program release.
Example. Consider the following original and xlated programs:
Original prog: Xlated prog:
0: r1 = 0x0 0: r1 = 0
1: *(u32 *)(r10 - 0x4) = r1 1: *(u32 *)(r10 -4) = r1
2: r2 = r10 2: r2 = r10
3: r2 += -0x4 3: r2 += -4
4: r1 = 0x0 ll 4: r1 = map[id:88]
6: call 0x1 6: r1 += 272
7: r0 = *(u32 *)(r2 +0)
8: if r0 >= 0x1 goto pc+3
9: r0 <<= 3
10: r0 += r1
11: goto pc+1
12: r0 = 0
7: r6 = r0 13: r6 = r0
8: if r6 == 0x0 goto +0x2 14: if r6 == 0x0 goto pc+4
9: call 0x76 15: r0 = 0xffffffff8d2079c0
17: r0 = *(u64 *)(r0 +0)
10: *(u64 *)(r6 + 0x0) = r0 18: *(u64 *)(r6 +0) = r0
11: r0 = 0x0 19: r0 = 0x0
12: exit 20: exit
An instruction array map, containing, e.g., instructions [0,4,7,12]
will be translated by the verifier to [0,4,13,20]. A map with
index 5 (the middle of 16-byte instruction) or indexes greater than 12
(outside the program boundaries) would be rejected.
The functionality provided by this patch will be extended in consequent
patches to implement BPF Static Keys, indirect jumps, and indirect calls.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Reviewed-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251105090410.1250500-2-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a new state NAPI_STATE_THREADED_BUSY_POLL to the NAPI state enum to
enable and disable threaded busy polling.
When threaded busy polling is enabled for a NAPI, enable
NAPI_STATE_THREADED also.
When the threaded NAPI is scheduled, set NAPI_STATE_IN_BUSY_POLL to
signal napi_complete_done not to rearm interrupts.
Whenever NAPI_STATE_THREADED_BUSY_POLL is unset, the
NAPI_STATE_IN_BUSY_POLL will be unset, napi_complete_done unsets the
NAPI_STATE_SCHED_THREADED bit also, which in turn will make the kthread
go to sleep.
Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Martin Karsten <mkarsten@uwaterloo.ca>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
Link: https://patch.msgid.link/20251028203007.575686-2-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To pick the changes in:
fe2bf6234e ("KVM: guest_memfd: Add INIT_SHARED flag, reject user page faults if not set")
d2042d8f96 ("KVM: Rework KVM_CAP_GUEST_MEMFD_MMAP into KVM_CAP_GUEST_MEMFD_FLAGS")
3d3a04fad2 ("KVM: Allow and advertise support for host mmap() on guest_memfd files")
That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the 'perf trace' ioctl syscall argument beautifiers.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
Please see tools/include/uapi/README for further details.
Cc: Sean Christopherson <seanjc@google.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Picking the changes from:
0864197382 ("drm: Move drm_gem ioctl kerneldoc to uapi file")
53096728b8 ("drm: Add DRM prime interface to reassign GEM handle")
Addressing these perf build warnings:
Warning: Kernel ABI header differences:
Now 'perf trace' and other code that might use the tools/perf/trace/beauty
autogenerated tables will be able to translate this new ioctl command into
a string:
$ tools/perf/trace/beauty/drm_ioctl.sh > before
$ cp include/uapi/drm/drm.h tools/include/uapi/drm/drm.h
$ tools/perf/trace/beauty/drm_ioctl.sh > after
$ diff -u before after
--- before 2025-11-03 09:57:34.832553174 -0300
+++ after 2025-11-03 09:57:47.969409428 -0300
@@ -111,6 +111,7 @@
[0xCF] = "SYNCOBJ_EVENTFD",
[0xD0] = "MODE_CLOSEFB",
[0xD1] = "SET_CLIENT_NAME",
+ [0xD2] = "GEM_CHANGE_HANDLE",
[DRM_COMMAND_BASE + 0x00] = "I915_INIT",
[DRM_COMMAND_BASE + 0x01] = "I915_FLUSH",
[DRM_COMMAND_BASE + 0x02] = "I915_FLIP",
$
Please see tools/include/uapi/README for further details.
Cc: Christian König <christian.koenig@amd.com>
Cc: David Francis <David.Francis@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Along the code reorganizations, the file has been keeping the original
comments about argv and envp which are no longer relevant to this file
anymore. Let's just drop them.
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
The efforts we go through by installing a single arch are counter
productive when the base directory already supports them all, and
the arch-specific files are really small. Let's make the "headers"
target simply install headers for all supported archs and stop
trying to build a hybrid "arch.h" file on the fly, to instead keep
the generic one. Now the same nolibc headers installation will be
usable with any arch-specific uapi installation.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
It's often recommended to only use inttypes.h instead of stdint.h for
portability reasons since the former is always present when the latter
is present, but not conversely, and the former includes the latter. Due
to this some simple programs fail to build when including inttypes.h.
Let's add one that simply includes nolibc.h to better support these
programs.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Modern programs tend to include sys/select.h to get FD_SET() and
FD_CLR() definitions as well as struct fd_set, but in our case it
didn't exist.
The definitions were moved from types.h to sys/select.h, which is
now included from nolibc.h, and the sys_select() definition moved
there as well from sys.h.
Signed-off-by: Willy Tarreau <w@1wt.eu>
[Thomas: adapt to current -next branch]
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Surprisingly we forgot to add this common one. It was added with a
per-arch guard allowing to later implement it in arch-specific asm
code like was done for a few other ones.
The test verifies that we don't search past the indicated length.
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
The help message says the headers are going to be installed into
tools/include/nolibc but this is only the default if $OUTPUT is not set,
so better clarify this (the current value of $OUTPUT is already shown).
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
This is generally useful and struct iovec is also needed for other
purposes such as ptrace.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
In principle, it is possible to use nolibc for only some object files in
a program. In that case, the startup code in _start and _start_c is not
going to be used. Add the NOLIBC_NO_RUNTIME compile time option to
disable it entirely and also remove anything that depends on it.
Doing this avoids warnings from modpost for UML as the _start_c code
references the main function from the .init.text section while it is not
inside .init itself.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Use the version of the attribute with underscores to avoid issues if
fallthrough has been defined by another header file already.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
For improved compatibility, print %m as "unknown error" when nolibc is
compiled using NOLIBC_IGNORE_ERRNO.
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Using errno is not possible when NOLIBC_IGNORE_ERRNO is set. Use
sys_lseek instead of lseek as that avoids using errno.
Fixes: 665fa8dea9 ("tools/nolibc: add support for directory access")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
There is no errno variable when NOLIBC_IGNORE_ERRNO is defined. As such,
simply print the message with "unknown error" rather than the integer
value of errno.
Fixes: acab7bcdb1 ("tools/nolibc/stdio: add perror() to report the errno value")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Since commit fb01ff635e ("tools/nolibc: keep brk(), sbrk(), mmap()
away from __sysret()") the implementation of mmap() does not use the
__sysret() macro anymore.
Remove the outdated comment.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Add support for deferred userspace unwind to perf.
Where perf currently relies on in-place stack unwinding; from NMI
context and all that. This moves the userspace part of the unwind to
right before the return-to-userspace.
This has two distinct benefits, the biggest is that it moves the
unwind to a faultable context. It becomes possible to fault in debug
info (.eh_frame, SFrame etc.) that might not otherwise be readily
available. And secondly, it de-duplicates the user callchain where
multiple samples happen during the same kernel entry.
To facilitate this the perf interface is extended with a new record
type:
PERF_RECORD_CALLCHAIN_DEFERRED
and two new attribute flags:
perf_event_attr::defer_callchain - to request the user unwind be deferred
perf_event_attr::defer_output - to request PERF_RECORD_CALLCHAIN_DEFERRED records
The existing PERF_RECORD_SAMPLE callchain section gets a new
context type:
PERF_CONTEXT_USER_DEFERRED
After which will come a single entry, denoting the 'cookie' of the
deferred callchain that should be attached here, matching the 'cookie'
field of the above mentioned PERF_RECORD_CALLCHAIN_DEFERRED.
The 'defer_callchain' flag is expected on all events with
PERF_SAMPLE_CALLCHAIN. The 'defer_output' flag is expect on the event
responsible for collecting side-band events (like mmap, comm etc.).
Setting 'defer_output' on multiple events will get you duplicated
PERF_RECORD_CALLCHAIN_DEFERRED records.
Based on earlier patches by Josh and Steven.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20251023150002.GR4067720@noisy.programming.kicks-ass.net
Dynptr currently caps size and offset at 24 bits, which isn’t sufficient
for file-backed use cases; even 32 bits can be limiting. Refactor dynptr
helpers/kfuncs to use 64-bit size and offset, ensuring consistency
across the APIs.
This change does not affect internals of xdp, skb or other dynptrs,
which continue to behave as before. Also it does not break binary
compatibility.
The widening enables large-file access support via dynptr, implemented
in the next patches.
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251026203853.135105-3-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
I recently got occasional build failures at -Os or -Oz that would always
involve waitpid(), where the assembler would complain about this:
init.s: Error: .size expression for waitpid.constprop.0 does not evaluate to a constant
And without -fno-asynchronous-unwind-tables it could also spit such
errors:
init.s:836: Error: CFI instruction used without previous .cfi_startproc
init.s:838: Error: .cfi_endproc without corresponding .cfi_startproc
init.s: Error: open CFI at the end of file; missing .cfi_endproc directive
A trimmed down reproducer is as simple as this:
int main(int argc, char **argv)
{
int ret, status;
if (argc == 0)
ret = waitpid(-1, &status, 0);
else
ret = waitpid(-1, &status, 0);
return status;
}
It produces the following asm code on x86_64:
.text
.section .text.nolibc_memmove_memcpy
.weak memmove
.weak memcpy
memmove:
memcpy:
movq %rdx, %rcx
(...)
retq
.section .text.nolibc_memset
.weak memset
memset:
xchgl %eax, %esi
movq %rdx, %rcx
pushq %rdi
rep stosb
popq %rax
retq
.type waitpid.constprop.0.isra.0, @function
waitpid.constprop.0.isra.0:
subq $8, %rsp
(...)
jmp *.L5(,%rax,8)
.section .rodata
.align 8
.align 4
.L5:
.quad .L10
(...)
.quad .L4
.text
.L10:
(...)
.cfi_def_cfa_offset 8
ret
.cfi_endproc
.LFE273:
.size waitpid.constprop.0.isra.0, .-waitpid.constprop.0.isra.0
It's a bit dense, but here's the explanation: the compiler has emitted a
".text" statement because it knows it's working in the .text section.
Then, our hand-written asm code for the mem* functions forced the section
to .text.something without the compiler knowing about it, so it thinks
the code is still being emitted for .text. As such, without any .section
statement, the waitpid.constprop.0.isra.0 label is in fact placed in the
previously created section, here .text.nolibc_memset.
The waitpid() function involves a switch/case statement that can be
turned to a jump table, which is what the compiler does with the .rodata
section, and after that it restores .text, which is no longer the
previous .text.nolibc_memset section. Then the CFI statements cross a
section, so does the .size calculation, which explains the error.
While a first approach consisting in placing an explicit ".text" at the
end of these functions was verified to work, it's still unreliable as
it depends on what the compiler remembers having emitted previously. A
better approach is to replace the ".section" with ".pushsection", and
place a ".popsection" at the end, so that these code blocks are agnostic
to where they're placed relative to other blocks.
Fixes: 553845eebd ("tools/nolibc: x86-64: Use `rep movsb` for `memcpy()` and `memmove()`")
Fixes: 12108aa8c1 ("tools/nolibc: x86-64: Use `rep stosb` for `memset()`")
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
If a socket has sk->sk_bypass_prot_mem flagged, the socket opts out
of the global protocol memory accounting.
This is easily controlled by net.core.bypass_prot_mem sysctl, but it
lacks flexibility.
Let's support flagging (and clearing) sk->sk_bypass_prot_mem via
bpf_setsockopt() at the BPF_CGROUP_INET_SOCK_CREATE hook.
int val = 1;
bpf_setsockopt(ctx, SOL_SOCKET, SK_BPF_BYPASS_PROT_MEM,
&val, sizeof(val));
As with net.core.bypass_prot_mem, this is inherited to child sockets,
and BPF always takes precedence over sysctl at socket(2) and accept(2).
SK_BPF_BYPASS_PROT_MEM is only supported at BPF_CGROUP_INET_SOCK_CREATE
and not supported on other hooks for some reasons:
1. UDP charges memory under sk->sk_receive_queue.lock instead
of lock_sock()
2. Modifying the flag after skb is charged to sk requires such
adjustment during bpf_setsockopt() and complicates the logic
unnecessarily
We can support other hooks later if a real use case justifies that.
Most changes are inline and hard to trace, but a microbenchmark on
__sk_mem_raise_allocated() during neper/tcp_stream showed that more
samples completed faster with sk->sk_bypass_prot_mem == 1. This will
be more visible under tcp_mem pressure (but it's not a fair comparison).
# bpftrace -e 'kprobe:__sk_mem_raise_allocated { @start[tid] = nsecs; }
kretprobe:__sk_mem_raise_allocated /@start[tid]/
{ @end[tid] = nsecs - @start[tid]; @times = hist(@end[tid]); delete(@start[tid]); }'
# tcp_stream -6 -F 1000 -N -T 256
Without bpf prog:
[128, 256) 3846 | |
[256, 512) 1505326 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[512, 1K) 1371006 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
[1K, 2K) 198207 |@@@@@@ |
[2K, 4K) 31199 |@ |
With bpf prog in the next patch:
(must be attached before tcp_stream)
# bpftool prog load sk_bypass_prot_mem.bpf.o /sys/fs/bpf/test type cgroup/sock_create
# bpftool cgroup attach /sys/fs/cgroup/test cgroup_inet_sock_create pinned /sys/fs/bpf/test
[128, 256) 6413 | |
[256, 512) 1868425 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[512, 1K) 1101697 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
[1K, 2K) 117031 |@@@@ |
[2K, 4K) 11773 | |
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Link: https://patch.msgid.link/20251014235604.3057003-6-kuniyu@google.com
Add a new klp diff subcommand which performs a binary diff between two
object files and extracts changed functions into a new object which can
then be linked into a livepatch module.
This builds on concepts from the longstanding out-of-tree kpatch [1]
project which began in 2012 and has been used for many years to generate
livepatch modules for production kernels. However, this is a complete
rewrite which incorporates hard-earned lessons from 12+ years of
maintaining kpatch.
Key improvements compared to kpatch-build:
- Integrated with objtool: Leverages objtool's existing control-flow
graph analysis to help detect changed functions.
- Works on vmlinux.o: Supports late-linked objects, making it
compatible with LTO, IBT, and similar.
- Simplified code base: ~3k fewer lines of code.
- Upstream: No more out-of-tree #ifdef hacks, far less cruft.
- Cleaner internals: Vastly simplified logic for symbol/section/reloc
inclusion and special section extraction.
- Robust __LINE__ macro handling: Avoids false positive binary diffs
caused by the __LINE__ macro by introducing a fix-patch-lines script
(coming in a later patch) which injects #line directives into the
source .patch to preserve the original line numbers at compile time.
Note the end result of this subcommand is not yet functionally complete.
Livepatch needs some ELF magic which linkers don't like:
- Two relocation sections (.rela*, .klp.rela*) for the same text
section.
- Use of SHN_LIVEPATCH to mark livepatch symbols.
Unfortunately linkers tend to mangle such things. To work around that,
klp diff generates a linker-compliant intermediate binary which encodes
the relevant KLP section/reloc/symbol metadata.
After module linking, a klp post-link step (coming soon) will clean up
the mess and convert the linked .ko into a fully compliant livepatch
module.
Note this subcommand requires the diffed binaries to have been compiled
with -ffunction-sections and -fdata-sections, and processed with
'objtool --checksum'. Those constraints will be handled by a klp-build
script introduced in a later patch.
Without '-ffunction-sections -fdata-sections', reliable object diffing
would be infeasible due to toolchain limitations:
- For intra-file+intra-section references, the compiler might
occasionally generated hard-coded instruction offsets instead of
relocations.
- Section-symbol-based references can be ambiguous:
- Overlapping or zero-length symbols create ambiguity as to which
symbol is being referenced.
- A reference to the end of a symbol (e.g., checking array bounds)
can be misinterpreted as a reference to the next symbol, or vice
versa.
A potential future alternative to '-ffunction-sections -fdata-sections'
would be to introduce a toolchain option that forces symbol-based
(non-section) relocations.
Acked-by: Petr Mladek <pmladek@suse.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
