Pull vfs mount updates from Christian Brauner:
- Add FSMOUNT_NAMESPACE flag to fsmount() that creates a new mount
namespace with the newly created filesystem attached to a copy of the
real rootfs. This returns a namespace file descriptor instead of an
O_PATH mount fd, similar to how OPEN_TREE_NAMESPACE works for
open_tree().
This allows creating a new filesystem and immediately placing it in a
new mount namespace in a single operation, which is useful for
container runtimes and other namespace-based isolation mechanisms.
This accompanies OPEN_TREE_NAMESPACE and avoids a needless detour via
OPEN_TREE_NAMESPACE to get the same effect. Will be especially useful
when you mount an actual filesystem to be used as the container
rootfs.
- Currently, creating a new mount namespace always copies the entire
mount tree from the caller's namespace. For containers and sandboxes
that intend to build their mount table from scratch this is wasteful:
they inherit a potentially large mount tree only to immediately tear
it down.
This series adds support for creating a mount namespace that contains
only a clone of the root mount, with none of the child mounts. Two
new flags are introduced:
- CLONE_EMPTY_MNTNS (0x400000000) for clone3(), using the 64-bit flag space
- UNSHARE_EMPTY_MNTNS (0x00100000) for unshare()
Both flags imply CLONE_NEWNS. The resulting namespace contains a
single nullfs root mount with an immutable empty directory. The
intended workflow is to then mount a real filesystem (e.g., tmpfs)
over the root and build the mount table from there.
- Allow MOVE_MOUNT_BENEATH to target the caller's rootfs, allowing to
switch out the rootfs without pivot_root(2).
The traditional approach to switching the rootfs involves
pivot_root(2) or a chroot_fs_refs()-based mechanism that atomically
updates fs->root for all tasks sharing the same fs_struct. This has
consequences for fork(), unshare(CLONE_FS), and setns().
This series instead decomposes root-switching into individually
atomic, locally-scoped steps:
fd_tree = open_tree(-EBADF, "/newroot", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
fchdir(fd_tree);
move_mount(fd_tree, "", AT_FDCWD, "/", MOVE_MOUNT_BENEATH | MOVE_MOUNT_F_EMPTY_PATH);
chroot(".");
umount2(".", MNT_DETACH);
Since each step only modifies the caller's own state, the
fork/unshare/setns races are eliminated by design.
A key step to making this possible is to remove the locked mount
restriction. Originally MOVE_MOUNT_BENEATH doesn't support mounting
beneath a mount that is locked. The locked mount protects the
underlying mount from being revealed. This is a core mechanism of
unshare(CLONE_NEWUSER | CLONE_NEWNS). The mounts in the new mount
namespace become locked. That effectively makes the new mount table
useless as the caller cannot ever get rid of any of the mounts no
matter how useless they are.
We can lift this restriction though. We simply transfer the locked
property from the top mount to the mount beneath. This works because
what we care about is to protect the underlying mount aka the parent.
The mount mounted between the parent and the top mount takes over the
job of protecting the parent mount from the top mount mount. This
leaves us free to remove the locked property from the top mount which
can consequently be unmounted:
unshare(CLONE_NEWUSER | CLONE_NEWNS)
and we inherit a clone of procfs on /proc then currently we cannot
unmount it as:
umount -l /proc
will fail with EINVAL because the procfs mount is locked.
After this series we can now do:
mount --beneath -t tmpfs tmpfs /proc
umount -l /proc
after which a tmpfs mount has been placed beneath the procfs mount.
The tmpfs mount has become locked and the procfs mount has become
unlocked.
This means you can safely modify an inherited mount table after
unprivileged namespace creation.
Afterwards we simply make it possible to move a mount beneath the
rootfs allowing to upgrade the rootfs.
Removing the locked restriction makes this very useful for containers
created with unshare(CLONE_NEWUSER | CLONE_NEWNS) to reshuffle an
inherited mount table safely and MOVE_MOUNT_BENEATH makes it possible
to switch out the rootfs instead of using the costly pivot_root(2).
* tag 'vfs-7.1-rc1.mount.v2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
selftests/namespaces: remove unused utils.h include from listns_efault_test
selftests/fsmount_ns: add missing TARGETS and fix cap test
selftests/empty_mntns: fix wrong CLONE_EMPTY_MNTNS hex value in comment
selftests/empty_mntns: fix statmount_alloc() signature mismatch
selftests/statmount: remove duplicate wait_for_pid()
mount: always duplicate mount
selftests/filesystems: add MOVE_MOUNT_BENEATH rootfs tests
move_mount: allow MOVE_MOUNT_BENEATH on the rootfs
move_mount: transfer MNT_LOCKED
selftests/filesystems: add clone3 tests for empty mount namespaces
selftests/filesystems: add tests for empty mount namespaces
namespace: allow creating empty mount namespaces
selftests: add FSMOUNT_NAMESPACE tests
selftests/statmount: add statmount_alloc() helper
tools: update mount.h header
mount: add FSMOUNT_NAMESPACE
mount: simplify __do_loopback()
mount: start iterating from start of rbtree
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
...
Pull bpf updates from Alexei Starovoitov:
- Welcome new BPF maintainers: Kumar Kartikeya Dwivedi, Eduard
Zingerman while Martin KaFai Lau reduced his load to Reviwer.
- Lots of fixes everywhere from many first time contributors. Thank you
All.
- Diff stat is dominated by mechanical split of verifier.c into
multiple components:
- backtrack.c: backtracking logic and jump history
- states.c: state equivalence
- cfg.c: control flow graph, postorder, strongly connected
components
- liveness.c: register and stack liveness
- fixups.c: post-verification passes: instruction patching, dead
code removal, bpf_loop inlining, finalize fastcall
8k line were moved. verifier.c still stands at 20k lines.
Further refactoring is planned for the next release.
- Replace dynamic stack liveness with static stack liveness based on
data flow analysis.
This improved the verification time by 2x for some programs and
equally reduced memory consumption. New logic is in liveness.c and
supported by constant folding in const_fold.c (Eduard Zingerman,
Alexei Starovoitov)
- Introduce BTF layout to ease addition of new BTF kinds (Alan Maguire)
- Use kmalloc_nolock() universally in BPF local storage (Amery Hung)
- Fix several bugs in linked registers delta tracking (Daniel Borkmann)
- Improve verifier support of arena pointers (Emil Tsalapatis)
- Improve verifier tracking of register bounds in min/max and tnum
domains (Harishankar Vishwanathan, Paul Chaignon, Hao Sun)
- Further extend support for implicit arguments in the verifier (Ihor
Solodrai)
- Add support for nop,nop5 instruction combo for USDT probes in libbpf
(Jiri Olsa)
- Support merging multiple module BTFs (Josef Bacik)
- Extend applicability of bpf_kptr_xchg (Kaitao Cheng)
- Retire rcu_trace_implies_rcu_gp() (Kumar Kartikeya Dwivedi)
- Support variable offset context access for 'syscall' programs (Kumar
Kartikeya Dwivedi)
- Migrate bpf_task_work and dynptr to kmalloc_nolock() (Mykyta
Yatsenko)
- Fix UAF in in open-coded task_vma iterator (Puranjay Mohan)
* tag 'bpf-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (241 commits)
selftests/bpf: cover short IPv4/IPv6 inputs with adjust_room
bpf: reject short IPv4/IPv6 inputs in bpf_prog_test_run_skb
selftests/bpf: Use memfd_create instead of shm_open in cgroup_iter_memcg
selftests/bpf: Add test for cgroup storage OOB read
bpf: Fix OOB in pcpu_init_value
selftests/bpf: Fix reg_bounds to match new tnum-based refinement
selftests/bpf: Add tests for non-arena/arena operations
bpf: Allow instructions with arena source and non-arena dest registers
bpftool: add missing fsession to the usage and docs of bpftool
docs/bpf: add missing fsession attach type to docs
bpf: add missing fsession to the verifier log
bpf: Move BTF checking logic into check_btf.c
bpf: Move backtracking logic to backtrack.c
bpf: Move state equivalence logic to states.c
bpf: Move check_cfg() into cfg.c
bpf: Move compute_insn_live_regs() into liveness.c
bpf: Move fixup/post-processing logic from verifier.c into fixups.c
bpf: Simplify do_check_insn()
bpf: Move checks for reserved fields out of the main pass
bpf: Delete unused variable
...
Pull module updates from Sami Tolvanen:
"Kernel symbol flags:
- Replace the separate *_gpl symbol sections (__ksymtab_gpl and
__kcrctab_gpl) with a unified symbol table and a new __kflagstab
section.
This section stores symbol flags, such as the GPL-only flag, as an
8-bit bitset for each exported symbol. This is a cleanup that
simplifies symbol lookup in the module loader by avoiding table
fragmentation and will allow a cleaner way to add more flags later
if needed.
Module signature UAPI:
- Move struct module_signature to the UAPI headers to allow reuse by
tools outside the kernel proper, such as kmod and
scripts/sign-file.
This also renames a few constants for clarity and drops unused
signature types as preparation for hash-based module integrity
checking work that's in progress.
Sysfs:
- Add a /sys/module/<module>/import_ns sysfs attribute to show the
symbol namespaces imported by loaded modules.
This makes it easier to verify driver API access at runtime on
systems that care about such things (e.g. Android).
Cleanups and fixes:
- Force sh_addr to 0 for all sections in module.lds. This prevents
non-zero section addresses when linking modules with 'ld.bfd -r',
which confused elfutils.
- Fix a memory leak of charp module parameters on module unload when
the kernel is configured with CONFIG_SYSFS=n.
- Override the -EEXIST error code returned by module_init() to
userspace. This prevents confusion with the errno reserved by the
module loader to indicate that a module is already loaded.
- Simplify the warning message and drop the stack dump on positive
returns from module_init().
- Drop unnecessary extern keywords from function declarations and
synchronize parse_args() arguments with their implementation"
* tag 'modules-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux: (23 commits)
module: Simplify warning on positive returns from module_init()
module: Override -EEXIST module return
documentation: remove references to *_gpl sections
module: remove *_gpl sections from vmlinux and modules
module: deprecate usage of *_gpl sections in module loader
module: use kflagstab instead of *_gpl sections
module: populate kflagstab in modpost
module: add kflagstab section to vmlinux and modules
module: define ksym_flags enumeration to represent kernel symbol flags
selftests/bpf: verify_pkcs7_sig: Use 'struct module_signature' from the UAPI headers
sign-file: use 'struct module_signature' from the UAPI headers
tools uapi headers: add linux/module_signature.h
module: Move 'struct module_signature' to UAPI
module: Give MODULE_SIG_STRING a more descriptive name
module: Give 'enum pkey_id_type' a more specific name
module: Drop unused signature types
extract-cert: drop unused definition of PKEY_ID_PKCS7
docs: symbol-namespaces: mention sysfs attribute
module: expose imported namespaces via sysfs
module: Remove extern keyword from param prototypes
...
Pull nolibc updates from Thomas Weißschuh:
- Many new features and optimizations to printf()
- Rename non-standard symbols to avoid collisions with application code
- Support for byteswap.h, endian.h, err.h and asprintf()
- 64-bit dev_t
- Smaller cleanups and fixes to the code and build system
* tag 'nolibc-20260412-for-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/nolibc/linux-nolibc: (61 commits)
selftests/nolibc: use gcc 15
tools/nolibc: support UBSAN on gcc
tools/nolibc: create __nolibc_no_sanitize_ubsan
selftests/nolibc: don't skip tests for unimplemented syscalls anymore
selftests/nolibc: explicitly handle ENOSYS from ptrace()
tools/nolibc: add byteorder conversions
tools/nolibc: add the _syscall() macro
tools/nolibc: move the call to __sysret() into syscall()
tools/nolibc: rename the internal macros used in syscall()
selftests/nolibc: only use libgcc when really necessary
selftests/nolibc: test the memory allocator
tools/nolibc: check for overflow in calloc() without divisions
tools/nolibc: add support for asprintf()
tools/nolibc: use __builtin_offsetof()
tools/nolibc: use makedev() in fstatat()
tools/nolibc: handle all major and minor numbers in makedev() and friends
tools/nolibc: make dev_t 64 bits wide
tools/nolibc: move the logic of makedev() and friends into functions
selftests/nolibc: add a test for stat().st_rdev
selftests/nolibc: add some tests for makedev() and friends
...
Add a ynl netdev family operation called queue-create that creates a
new queue on a netdevice:
name: queue-create
attribute-set: queue
flags: [admin-perm]
do:
request:
attributes:
- ifindex
- type
- lease
reply: &queue-create-op
attributes:
- id
This is a generic operation such that it can be extended for various
use cases in future. Right now it is mandatory to specify ifindex,
the queue type which is enforced to rx and a lease. The newly created
queue id is returned to the caller.
A queue from a virtual device can have a lease which refers to another
queue from a physical device. This is useful for memory providers
and AF_XDP operations which take an ifindex and queue id to allow
applications to bind against virtual devices in containers. The lease
couples both queues together and allows to proxy the operations from
a virtual device in a container to the physical device.
In future, the nested lease attribute can be lifted and made optional
for other use-cases such as dynamic queue creation for physical
netdevs. The lack of lease and the specification of the physical
device as an ifindex will imply that we need a real queue to be
allocated. Similarly, the queue type enforcement to rx can then be
lifted as well to support tx.
An early implementation had only driver-specific integration [0], but
in order for other virtual devices to reuse, it makes sense to have
this as a generic API in core net.
For leasing queues, the virtual netdev must have real_num_rx_queues
less than num_rx_queues at the time of calling queue-create. The
queue-type must be rx as only rx queues are supported for leasing
for now. We also enforce that the queue-create ifindex must point
to a virtual device, and that the nested lease attribute's ifindex
must point to a physical device. The nested lease attribute set
contains a netns-id attribute which is optional and can specify a
netns-id relative to the caller's netns. It requires cap_net_admin
and if the netns-id attribute is not specified, the lease ifindex
will be retrieved from the current netns. Also, it is modeled as
an s32 type similarly as done elsewhere in the stack.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://bpfconf.ebpf.io/bpfconf2025/bpfconf2025_material/lsfmmbpf_2025_netkit_borkmann.pdf [0]
Link: https://patch.msgid.link/20260402231031.447597-2-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The standard syscall() function or macro uses the libc return value
convention. Errors returned from the kernel as negative values are
stored in errno and -1 is returned. Users who want to avoid using
errno don't have a way to call raw syscalls and check the returned
error.
Add a new macro _syscall() which works like the standard syscall()
but passes through the return value from the kernel unchanged.
The naming scheme and return values match the named _sys_foo()
system call wrappers already part of nolibc.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260405-nolibc-syscall-v1-3-e5b12bc63211@weissschuh.net
__sysret() transforms the return value from the kernel into the libc
return value convention. There is no reason for it to be called in the
middle of the internals of the syscall() implementation macros.
Move the call up, directly into syscall(), to make the code simpler.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260405-nolibc-syscall-v1-2-e5b12bc63211@weissschuh.net
On some architectures without native division instructions
the division can generate calls into libgcc/compiler-rt.
This library might not be available, so its use should be avoided.
Use the compiler builtin to check for overflows without needing a
division. The builtin has been available since GCC 3 and clang 3.8.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260404-nolibc-asprintf-v2-1-17d2d0df9763@weissschuh.net
The current custom implementation of offsetof() fails UBSAN:
runtime error: member access within null pointer of type 'struct ...'
This means that all its users, including container_of(), free() and
realloc(), fail.
Use __builtin_offsetof() instead which does not have this issue and
has been available since GCC 4 and clang 3.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260401-nolibc-asprintf-v1-1-46292313439f@weissschuh.net
statx() returns both 32-bit minor and major numbers. For both of them to
fit into the 'dev_t' in 'struct stat', that needs to be 64 bits wide.
The other uses of 'dev_t' in nolibc are makedev() and friends and
mknod(). makedev() and friends are going to be adapted in an upcoming
commit and mknod() will silently truncate 'dev_t' to 'unsigned int' in
the kernel, similar to other libcs.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260404-nolibc-makedev-v2-4-456a429bf60c@weissschuh.net
Functions make it easier to keep the input and output types straight and
avoid duplicate evaluations of their arguments.
Also these functions will become a bit more complex to handle full
64-bit 'dev_t' which is easier to read in a function.
Still stay compatible with code which expects these to be macros.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260404-nolibc-makedev-v2-3-456a429bf60c@weissschuh.net
For (eg) "%*.*s" treat a negative field width as a request to left align
the output (the same as the '-' flag), and a negative precision to
request the default precision.
Set the default precision to -1 (not INT_MAX) and add explicit checks
to the string handling for negative values (makes the tet unsigned).
For numeric output check for 'precision >= 0' instead of testing
_NOLIBC_PF_FLAGS_CONTAIN(flags, '.').
This needs an inverted test, some extra goto and removes an indentation.
The changed conditionals fix printf("%0-#o", 0) - but '0' and '-' shouldn't
both be specified.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Link: https://patch.msgid.link/20260323112247.3196-1-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Clarify bpf_ringbuf_discard() documentation for BPF_RB_NO_WAKEUP.
Discarded ring buffer records are still left in the ring buffer and are
only skipped when user space consumes them. This can matter when
BPF_RB_NO_WAKEUP is used: a later submit relying on adaptive wakeup
might not wake the consumer, because the discarded record still needs to
be consumed first.
Scenario:
epoll_wait(rb_fd); // blocks
rec = bpf_ringbuf_reserve(&rb, ...);
bpf_ringbuf_discard(rec, BPF_RB_NO_WAKEUP);
rec = bpf_ringbuf_reserve(&rb, ...);
bpf_ringbuf_submit(rec, 0); // valid record, but no wakeup
Document this in bpf_ringbuf_discard() to make the interaction between
discarded records, user-space consumption, and adaptive wakeups explicit.
Reported-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260331130612.3762433-1-eyal.birger@gmail.com
----
v2: adapt wording per feedback from Andrii.
To pick up the changes in:
6ffd853b0b ("build_bug.h: correct function parameters names in kernel-doc")
That just add some comments, addressing this perf tools build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/linux/build_bug.h include/linux/build_bug.h
Please take a look at tools/include/uapi/README for further info on this
synchronization process.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ian Rogers <irogers@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes in:
da142f3d37 ("KVM: Remove subtle "struct kvm_stats_desc" pseudo-overlay")
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>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The sys_foo() naming scheme used by the syscall wrappers may collide
with application symbols. Especially as 'sys_' is an obvious naming
scheme an application may choose for its own custom systemcall wrappers.
Avoid these conflicts by using an leading underscore which moves the
names into the implementation's namespace. This naming scheme was chosen
over a '__nolibc_' prefix, as these functions are not an implementation
detail but a documented interface meant to be used by applications.
While this may break some existing users, adapting them should be
straightforward. Given that nolibc is most-likely vendored, no
unexpected breakage should happen. No in-tree users are affected.
These conflicts happen when compiling some of the kernel selftests
with nolibc.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260319-nolibc-namespacing-v1-1-33c22eaddb5e@weissschuh.net
With -std=c89 the macro __STDC_VERSION__ is not defined.
While undefined identifiers in '#if' directives are assumed to be '0',
with -Wundef a warning is emitted.
Avoid the warning by explicitly falling back to '0' if __STDC_VERSION__
is not provided by the preprocessor.
Fixes: 37219aa5b1 ("tools/nolibc: add __nolibc_static_assert()")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260318-nolibc-wundef-v1-1-fcb7f9ac7298@weissschuh.net
Add support for the GNU extensions 'program_invocation_name' and
'program_invocation_short_name'. These are useful to print error
messages, which by convention include the program name.
As these are global variables which take up memory even if not used,
similar to 'errno', gate them behind NOLIBC_IGNORE_ERRNO.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260318-nolibc-err-h-v4-1-08247a694bd9@weissschuh.net
Octal output isn't often used, but adding it costs very little.
Supporting "%#o" is mildly annoying, it has to add a leading '0' if
there isn't one present. In simple cases this is the same as adding a sign
of '0' - but that adds an extra '0' in a few places.
So you need 3 tests, %o, # and no leading '0' (which can only be checked
after the zero pad for precision).
If all the test are deferred until after zero padding then too many values
are 'live' across the call to _nolibc_u64toa_base() and get spilled to stack.
Hence the check that ignores the 'sign' if it is the same as the first
character of the output string.
Add tests for octal output.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-17-david.laight.linux@gmail.com
[Thomas: avoid a -Wsign-compare]
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Includes support for variable field widths (eg "%*.*d").
Zero padding is limited to 31 zero characters.
This is wider than the largest numeric field so shouldn't be a problem.
All the standard printf formats are now supported except octal
and floating point.
Add tests for new features
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-16-david.laight.linux@gmail.com
[Thomas: fixup testcases for musl libc]
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
The output for %#x is almost the same as that for %p, both output in
hexadecimal with a leading "0x".
However for zero %#x should just output "0" (the same as decimal and ocal).
For %p match glibc and output "(nil)" rather than "0x0" or "0".
Add tests for "%#x", "% d", "%+d" and passing NULL to "%p".
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-14-david.laight.linux@gmail.com
[Thomas: fix up testcases for musl libc]
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Length modifiers t (ptrdiff_t) and z (size_t) are aliases for l (long),
q and L are 64bit the same as j (intmax).
Format i is an alias for d and X similar to x but upper case.
Supporting them is mostly just adding the relevant bit to the bit
pattern used for matching characters.
Although %X is detected the output will be lower case.
Change/add tests to use conversions i and X, and length modifiers L and ll.
Use the correct minimum value for "%Li".
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-10-david.laight.linux@gmail.com
[Thomas: Fix up testcases for musl libc]
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Use flags bits (1u << (ch & 31)) for the flags, length modifiers, and
conversion specifiers.
This makes it easy to test for multiple values at once.
Detect the conversion flags " #+-0" although they are currently all ignored.
Unconditionally generate the signed values (for %d) to remove a second
set of checks for the size.
Separate out the formatting of single characters from numbers.
Output the sign for negative values then negate and treat as unsigned.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-9-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Upcoming changes will need to use goto to jump to the code that
outputs characters.
Use 'goto do_output' to output a known number of characters.
Use 'goto do_strlen_output' to output a '\0' terminated string.
Removes a level of indentation from the format processing code.
The change is best reviewed using 'git diff -b' after applying it.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-8-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Move the check for the length modifiers into the format processing
between the field width and conversion specifier.
This lets the loop be simplified and a 'fast scan' for a format start
used.
If an error is detected (eg an invalid conversion specifier) then
copy the invalid format to the output buffer.
Reduces code size by about 10% on x86-64.
Some versions of gcc bloat this version by generating a jump table.
All goes away in the later patches.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-7-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
strerror() can be the only part of a program that has a .data section.
This requires 4k in the program file.
Add a simple implementation of strerror_r() and use that in strerror()
so that the "errno=" string is copied at run-time.
Use __builtin_memcpy() because that optimises away the input string
and just writes the required constants to the target buffer.
Code size change largely depends on whether the inlining decision for
strerror() changes.
Change the tests to use the normal EXPECT_VFPRINTF() when testing %m.
Skip the tests when !is_nolibc.
Signed-off-by: David Laight <david.laight.linux@gmail.com>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://patch.msgid.link/20260308113742.12649-4-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
