This reverts commit 79996b45f7.
Revert the change that restricts a send provided buffer to be zero, so
it will always consume the whole buffer. This is strictly needed for
partial consumption, as the send may very well be a subset of the
current buffer. In fact, that's the intended use case.
For non-incremental provided buffer rings, an application should set
sqe->len carefully to avoid the potential issue described in the
reverted commit. It is recommended that '0' still be set for len for
that case, if the application is set on maintaining more than 1 send
inflight for the same socket. This is somewhat of a nonsensical thing
to do.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just like what is being done on the recv side, if we only map a single
segment, then use ITER_UBUF for mapping it. That's more efficient than
using an ITER_IOVEC.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If a send is issued marked with IOSQE_BUFFER_SELECT for selecting a
buffer, unless it's a bundle, it should not select multiple buffers.
Cc: stable@vger.kernel.org
Fixes: a05d1f625c ("io_uring/net: support bundles for send")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the iovec inside the kmsg isn't already allocated AND one gets
expanded beyond the fixed size, then the request may not already have
been marked for cleanup. Ensure that it is.
Cc: stable@vger.kernel.org
Fixes: a05d1f625c ("io_uring/net: support bundles for send")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the iovec inside the kmsg isn't already allocated AND one gets
expanded beyond the fixed size, then the request may not already have
been marked for cleanup. Ensure that it is.
Cc: stable@vger.kernel.org
Fixes: 2f9c9515bd ("io_uring/net: support bundles for recv")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
patchsets (devmem among them) did not make it in time.
Core & protocols
----------------
- Use local_lock in addition to local_bh_disable() to protect per-CPU
resources in networking, a step closer for local_bh_disable() not
to act as a big lock on PREEMPT_RT.
- Use flex array for netdevice priv area, ensure its cache alignment.
- Add a sysctl knob to allow user to specify a default rto_min at socket
init time. Bit of a big hammer but multiple companies were
independently carrying such patch downstream so clearly it's useful.
- Support scheduling transmission of packets based on CLOCK_TAI.
- Un-pin TCP TIMEWAIT timer to avoid it firing on CPUs later cordoned off
using cpusets.
- Support multiple L2TPv3 UDP tunnels using the same 5-tuple address.
- Allow configuration of multipath hash seed, to both allow synchronizing
hashing of two routers, and preventing partial accidental sync.
- Improve TCP compliance with RFC 9293 for simultaneous connect().
- Support sending NAT keepalives in IPsec ESP in UDP states. Userspace
IKE daemon had to do this before, but the kernel can better keep
track of it.
- Support sending supervision HSR frames with MAC addresses stored in
ProxyNodeTable when RedBox (i.e. HSR-SAN) is enabled.
- Introduce IPPROTO_SMC for selecting SMC when socket is created.
- Allow UDP GSO transmit from devices with no checksum offload.
- openvswitch: add packet sampling via psample, separating the sampled
traffic from "upcall" packets sent to user space for forwarding.
- nf_tables: shrink memory consumption for transaction objects.
Things we sprinkled into general kernel code
--------------------------------------------
- Power Sequencing subsystem (used by Qualcomm Bluetooth driver
for QCA6390).
- Add IRQ information in sysfs for auxiliary bus.
- Introduce guard definition for local_lock.
- Add aligned flavor of __cacheline_group_{begin, end}() markings for
grouping fields in structures.
BPF
---
- Notify user space (via epoll) when a struct_ops object is getting
detached/unregistered.
- Add new kfuncs for a generic, open-coded bits iterator.
- Enable BPF programs to declare arrays of kptr, bpf_rb_root, and
bpf_list_head.
- Support resilient split BTF which cuts down on duplication and makes
BTF as compact as possible WRT BTF from modules.
- Add support for dumping kfunc prototypes from BTF which enables both
detecting as well as dumping compilable prototypes for kfuncs.
- riscv64 BPF JIT improvements in particular to add 12-argument support
for BPF trampolines and to utilize bpf_prog_pack for the latter.
- Add the capability to offload the netfilter flowtable in XDP layer
through kfuncs.
Driver API
----------
- Allow users to configure IRQ tresholds between which automatic IRQ
moderation can choose.
- Expand Power Sourcing (PoE) status with power, class and failure
reason. Support setting power limits.
- Track additional RSS contexts in the core, make sure configuration
changes don't break them.
- Support IPsec crypto offload for IPv6 ESP and IPv4 UDP-encapsulated ESP
data paths.
- Support updating firmware on SFP modules.
Tests and tooling
-----------------
- mptcp: use net/lib.sh to manage netns.
- TCP-AO and TCP-MD5: replace debug prints used by tests with
tracepoints.
- openvswitch: make test self-contained (don't depend on OvS CLI tools).
Drivers
-------
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- increase the max total outstanding PTP TX packets to 4
- add timestamping statistics support
- implement netdev_queue_mgmt_ops
- support new RSS context API
- Intel (100G, ice, idpf):
- implement FEC statistics and dumping signal quality indicators
- support E825C products (with 56Gbps PHYs)
- nVidia/Mellanox:
- support HW-GRO
- mlx4/mlx5: support per-queue statistics via netlink
- obey the max number of EQs setting in sub-functions
- AMD/Solarflare:
- support new RSS context API
- AMD/Pensando:
- ionic: rework fix for doorbell miss to lower overhead
and skip it on new HW
- Wangxun:
- txgbe: support Flow Director perfect filters
- Ethernet NICs consumer, embedded and virtual:
- Add driver for Tehuti Networks TN40xx chips
- Add driver for Meta's internal NIC chips
- Add driver for Ethernet MAC on Airoha EN7581 SoCs
- Add driver for Renesas Ethernet-TSN devices
- Google cloud vNIC:
- flow steering support
- Microsoft vNIC:
- support page sizes other than 4KB on ARM64
- vmware vNIC:
- support latency measurement (update to version 9)
- VirtIO net:
- support for Byte Queue Limits
- support configuring thresholds for automatic IRQ moderation
- support for AF_XDP Rx zero-copy
- Synopsys (stmmac):
- support for STM32MP13 SoC
- let platforms select the right PCS implementation
- TI:
- icssg-prueth: add multicast filtering support
- icssg-prueth: enable PTP timestamping and PPS
- Renesas:
- ravb: improve Rx performance 30-400% by using page pool,
theaded NAPI and timer-based IRQ coalescing
- ravb: add MII support for R-Car V4M
- Cadence (macb):
- macb: add ARP support to Wake-On-LAN
- Cortina:
- use phylib for RX and TX pause configuration
- Ethernet switches:
- nVidia/Mellanox:
- support configuration of multipath hash seed
- report more accurate max MTU
- use page_pool to improve Rx performance
- MediaTek:
- mt7530: add support for bridge port isolation
- Qualcomm:
- qca8k: add support for bridge port isolation
- Microchip:
- lan9371/2: add 100BaseTX PHY support
- NXP:
- vsc73xx: implement VLAN operations
- Ethernet PHYs:
- aquantia: enable support for aqr115c
- aquantia: add support for PHY LEDs
- realtek: add support for rtl8224 2.5Gbps PHY
- xpcs: add memory-mapped device support
- add BroadR-Reach link mode and support in Broadcom's PHY driver
- CAN:
- add document for ISO 15765-2 protocol support
- mcp251xfd: workaround for erratum DS80000789E, use timestamps
to catch when device returns incorrect FIFO status
- WiFi:
- mac80211/cfg80211:
- parse Transmit Power Envelope (TPE) data in mac80211 instead of
in drivers
- improvements for 6 GHz regulatory flexibility
- multi-link improvements
- support multiple radios per wiphy
- remove DEAUTH_NEED_MGD_TX_PREP flag
- Intel (iwlwifi):
- bump FW API to 91 for BZ/SC devices
- report 64-bit radiotap timestamp
- enable P2P low latency by default
- handle Transmit Power Envelope (TPE) advertised by AP
- remove support for older FW for new devices
- fast resume (keeping the device configured)
- mvm: re-enable Multi-Link Operation (MLO)
- aggregation (A-MSDU) optimizations
- MediaTek (mt76):
- mt7925 Multi-Link Operation (MLO) support
- Qualcomm (ath10k):
- LED support for various chipsets
- Qualcomm (ath12k):
- remove unsupported Tx monitor handling
- support channel 2 in 6 GHz band
- support Spatial Multiplexing Power Save (SMPS) in 6 GHz band
- supprt multiple BSSID (MBSSID) and Enhanced Multi-BSSID
Advertisements (EMA)
- support dynamic VLAN
- add panic handler for resetting the firmware state
- DebugFS support for datapath statistics
- WCN7850: support for Wake on WLAN
- Microchip (wilc1000):
- read MAC address during probe to make it visible to user space
- suspend/resume improvements
- TI (wl18xx):
- support newer firmware versions
- RealTek (rtw89):
- preparation for RTL8852BE-VT support
- Wake on WLAN support for WiFi 6 chips
- 36-bit PCI DMA support
- RealTek (rtlwifi):
- RTL8192DU support
- Broadcom (brcmfmac):
- Management Frame Protection support (to enable WPA3)
- Bluetooth:
- qualcomm: use the power sequencer for QCA6390
- btusb: mediatek: add ISO data transmission functions
- hci_bcm4377: add BCM4388 support
- btintel: add support for BlazarU core
- btintel: add support for Whale Peak2
- btnxpuart: add support for AW693 A1 chipset
- btnxpuart: add support for IW615 chipset
- btusb: add Realtek RTL8852BE support ID 0x13d3:0x3591
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Not much excitement - a handful of large patchsets (devmem among them)
did not make it in time.
Core & protocols:
- Use local_lock in addition to local_bh_disable() to protect per-CPU
resources in networking, a step closer for local_bh_disable() not
to act as a big lock on PREEMPT_RT
- Use flex array for netdevice priv area, ensure its cache alignment
- Add a sysctl knob to allow user to specify a default rto_min at
socket init time. Bit of a big hammer but multiple companies were
independently carrying such patch downstream so clearly it's useful
- Support scheduling transmission of packets based on CLOCK_TAI
- Un-pin TCP TIMEWAIT timer to avoid it firing on CPUs later cordoned
off using cpusets
- Support multiple L2TPv3 UDP tunnels using the same 5-tuple address
- Allow configuration of multipath hash seed, to both allow
synchronizing hashing of two routers, and preventing partial
accidental sync
- Improve TCP compliance with RFC 9293 for simultaneous connect()
- Support sending NAT keepalives in IPsec ESP in UDP states.
Userspace IKE daemon had to do this before, but the kernel can
better keep track of it
- Support sending supervision HSR frames with MAC addresses stored in
ProxyNodeTable when RedBox (i.e. HSR-SAN) is enabled
- Introduce IPPROTO_SMC for selecting SMC when socket is created
- Allow UDP GSO transmit from devices with no checksum offload
- openvswitch: add packet sampling via psample, separating the
sampled traffic from "upcall" packets sent to user space for
forwarding
- nf_tables: shrink memory consumption for transaction objects
Things we sprinkled into general kernel code:
- Power Sequencing subsystem (used by Qualcomm Bluetooth driver for
QCA6390) [ Already merged separately - Linus ]
- Add IRQ information in sysfs for auxiliary bus
- Introduce guard definition for local_lock
- Add aligned flavor of __cacheline_group_{begin, end}() markings for
grouping fields in structures
BPF:
- Notify user space (via epoll) when a struct_ops object is getting
detached/unregistered
- Add new kfuncs for a generic, open-coded bits iterator
- Enable BPF programs to declare arrays of kptr, bpf_rb_root, and
bpf_list_head
- Support resilient split BTF which cuts down on duplication and
makes BTF as compact as possible WRT BTF from modules
- Add support for dumping kfunc prototypes from BTF which enables
both detecting as well as dumping compilable prototypes for kfuncs
- riscv64 BPF JIT improvements in particular to add 12-argument
support for BPF trampolines and to utilize bpf_prog_pack for the
latter
- Add the capability to offload the netfilter flowtable in XDP layer
through kfuncs
Driver API:
- Allow users to configure IRQ tresholds between which automatic IRQ
moderation can choose
- Expand Power Sourcing (PoE) status with power, class and failure
reason. Support setting power limits
- Track additional RSS contexts in the core, make sure configuration
changes don't break them
- Support IPsec crypto offload for IPv6 ESP and IPv4 UDP-encapsulated
ESP data paths
- Support updating firmware on SFP modules
Tests and tooling:
- mptcp: use net/lib.sh to manage netns
- TCP-AO and TCP-MD5: replace debug prints used by tests with
tracepoints
- openvswitch: make test self-contained (don't depend on OvS CLI
tools)
Drivers:
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- increase the max total outstanding PTP TX packets to 4
- add timestamping statistics support
- implement netdev_queue_mgmt_ops
- support new RSS context API
- Intel (100G, ice, idpf):
- implement FEC statistics and dumping signal quality indicators
- support E825C products (with 56Gbps PHYs)
- nVidia/Mellanox:
- support HW-GRO
- mlx4/mlx5: support per-queue statistics via netlink
- obey the max number of EQs setting in sub-functions
- AMD/Solarflare:
- support new RSS context API
- AMD/Pensando:
- ionic: rework fix for doorbell miss to lower overhead and
skip it on new HW
- Wangxun:
- txgbe: support Flow Director perfect filters
- Ethernet NICs consumer, embedded and virtual:
- Add driver for Tehuti Networks TN40xx chips
- Add driver for Meta's internal NIC chips
- Add driver for Ethernet MAC on Airoha EN7581 SoCs
- Add driver for Renesas Ethernet-TSN devices
- Google cloud vNIC:
- flow steering support
- Microsoft vNIC:
- support page sizes other than 4KB on ARM64
- vmware vNIC:
- support latency measurement (update to version 9)
- VirtIO net:
- support for Byte Queue Limits
- support configuring thresholds for automatic IRQ moderation
- support for AF_XDP Rx zero-copy
- Synopsys (stmmac):
- support for STM32MP13 SoC
- let platforms select the right PCS implementation
- TI:
- icssg-prueth: add multicast filtering support
- icssg-prueth: enable PTP timestamping and PPS
- Renesas:
- ravb: improve Rx performance 30-400% by using page pool,
theaded NAPI and timer-based IRQ coalescing
- ravb: add MII support for R-Car V4M
- Cadence (macb):
- macb: add ARP support to Wake-On-LAN
- Cortina:
- use phylib for RX and TX pause configuration
- Ethernet switches:
- nVidia/Mellanox:
- support configuration of multipath hash seed
- report more accurate max MTU
- use page_pool to improve Rx performance
- MediaTek:
- mt7530: add support for bridge port isolation
- Qualcomm:
- qca8k: add support for bridge port isolation
- Microchip:
- lan9371/2: add 100BaseTX PHY support
- NXP:
- vsc73xx: implement VLAN operations
- Ethernet PHYs:
- aquantia: enable support for aqr115c
- aquantia: add support for PHY LEDs
- realtek: add support for rtl8224 2.5Gbps PHY
- xpcs: add memory-mapped device support
- add BroadR-Reach link mode and support in Broadcom's PHY driver
- CAN:
- add document for ISO 15765-2 protocol support
- mcp251xfd: workaround for erratum DS80000789E, use timestamps to
catch when device returns incorrect FIFO status
- WiFi:
- mac80211/cfg80211:
- parse Transmit Power Envelope (TPE) data in mac80211 instead
of in drivers
- improvements for 6 GHz regulatory flexibility
- multi-link improvements
- support multiple radios per wiphy
- remove DEAUTH_NEED_MGD_TX_PREP flag
- Intel (iwlwifi):
- bump FW API to 91 for BZ/SC devices
- report 64-bit radiotap timestamp
- enable P2P low latency by default
- handle Transmit Power Envelope (TPE) advertised by AP
- remove support for older FW for new devices
- fast resume (keeping the device configured)
- mvm: re-enable Multi-Link Operation (MLO)
- aggregation (A-MSDU) optimizations
- MediaTek (mt76):
- mt7925 Multi-Link Operation (MLO) support
- Qualcomm (ath10k):
- LED support for various chipsets
- Qualcomm (ath12k):
- remove unsupported Tx monitor handling
- support channel 2 in 6 GHz band
- support Spatial Multiplexing Power Save (SMPS) in 6 GHz band
- supprt multiple BSSID (MBSSID) and Enhanced Multi-BSSID
Advertisements (EMA)
- support dynamic VLAN
- add panic handler for resetting the firmware state
- DebugFS support for datapath statistics
- WCN7850: support for Wake on WLAN
- Microchip (wilc1000):
- read MAC address during probe to make it visible to user space
- suspend/resume improvements
- TI (wl18xx):
- support newer firmware versions
- RealTek (rtw89):
- preparation for RTL8852BE-VT support
- Wake on WLAN support for WiFi 6 chips
- 36-bit PCI DMA support
- RealTek (rtlwifi):
- RTL8192DU support
- Broadcom (brcmfmac):
- Management Frame Protection support (to enable WPA3)
- Bluetooth:
- qualcomm: use the power sequencer for QCA6390
- btusb: mediatek: add ISO data transmission functions
- hci_bcm4377: add BCM4388 support
- btintel: add support for BlazarU core
- btintel: add support for Whale Peak2
- btnxpuart: add support for AW693 A1 chipset
- btnxpuart: add support for IW615 chipset
- btusb: add Realtek RTL8852BE support ID 0x13d3:0x3591"
* tag 'net-next-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1589 commits)
eth: fbnic: Fix spelling mistake "tiggerring" -> "triggering"
tcp: Replace strncpy() with strscpy()
wifi: ath12k: fix build vs old compiler
tcp: Don't access uninit tcp_rsk(req)->ao_keyid in tcp_create_openreq_child().
eth: fbnic: Write the TCAM tables used for RSS control and Rx to host
eth: fbnic: Add L2 address programming
eth: fbnic: Add basic Rx handling
eth: fbnic: Add basic Tx handling
eth: fbnic: Add link detection
eth: fbnic: Add initial messaging to notify FW of our presence
eth: fbnic: Implement Rx queue alloc/start/stop/free
eth: fbnic: Implement Tx queue alloc/start/stop/free
eth: fbnic: Allocate a netdevice and napi vectors with queues
eth: fbnic: Add FW communication mechanism
eth: fbnic: Add message parsing for FW messages
eth: fbnic: Add register init to set PCIe/Ethernet device config
eth: fbnic: Allocate core device specific structures and devlink interface
eth: fbnic: Add scaffolding for Meta's NIC driver
PCI: Add Meta Platforms vendor ID
net/sched: cls_flower: propagate tca[TCA_OPTIONS] to NL_REQ_ATTR_CHECK
...
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Merge tag 'for-6.11/io_uring-20240714' of git://git.kernel.dk/linux
Pull io_uring updates from Jens Axboe:
"Here are the io_uring updates queued up for 6.11.
Nothing major this time around, various minor improvements and
cleanups/fixes. This contains:
- Add bind/listen opcodes. Main motivation is to support direct
descriptors, to avoid needing a regular fd just for doing these two
operations (Gabriel)
- Probe fixes (Gabriel)
- Treat io-wq work flags as atomics. Not fixing a real issue, but may
as well and it silences a KCSAN warning (me)
- Cleanup of rsrc __set_current_state() usage (me)
- Add 64-bit for {m,f}advise operations (me)
- Improve performance of data ring messages (me)
- Fix for ring message overflow posting (Pavel)
- Fix for freezer interaction with TWA_NOTIFY_SIGNAL. Not strictly an
io_uring thing, but since TWA_NOTIFY_SIGNAL was originally added
for faster task_work signaling for io_uring, bundling it with this
pull (Pavel)
- Add Pavel as a co-maintainer
- Various cleanups (me, Thorsten)"
* tag 'for-6.11/io_uring-20240714' of git://git.kernel.dk/linux: (28 commits)
io_uring/net: check socket is valid in io_bind()/io_listen()
kernel: rerun task_work while freezing in get_signal()
io_uring/io-wq: limit retrying worker initialisation
io_uring/napi: Remove unnecessary s64 cast
io_uring/net: cleanup io_recv_finish() bundle handling
io_uring/msg_ring: fix overflow posting
MAINTAINERS: change Pavel Begunkov from io_uring reviewer to maintainer
io_uring/msg_ring: use kmem_cache_free() to free request
io_uring/msg_ring: check for dead submitter task
io_uring/msg_ring: add an alloc cache for io_kiocb entries
io_uring/msg_ring: improve handling of target CQE posting
io_uring: add io_add_aux_cqe() helper
io_uring: add remote task_work execution helper
io_uring/msg_ring: tighten requirement for remote posting
io_uring: Allocate only necessary memory in io_probe
io_uring: Fix probe of disabled operations
io_uring: Introduce IORING_OP_LISTEN
io_uring: Introduce IORING_OP_BIND
net: Split a __sys_listen helper for io_uring
net: Split a __sys_bind helper for io_uring
...
Combine the two cases that check for whether or not this is a bundle,
rather than having them as separate checks. This is easier to reduce,
and it reduces the text associated with it as well.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For bundle receives to function properly, the previous iteration msg_inq
value is needed to make a judgement call on how much data there is to
receive. A previous fix ended up clearing it earlier as an error case
would potentially errantly set IORING_CQE_F_SOCK_NONEMPTY if the request
got failed.
Move the assignment to post assigning buffers for the receive, but
ensure that it's cleared for the buffer selection error case. With that,
buffer selection has the right msg_inq value and can correctly bundle
receives as designed.
Noticed while testing where it was apparent than more than 1 buffer was
never received. After fix was in place, multiple buffers are correctly
picked for receive. This provides a 10x speedup for the test case, as
the buffer size used was 64b.
Fixes: 18414a4a2e ("io_uring/net: assign kmsg inq/flags before buffer selection")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, io_uring's io_sg_from_iter() duplicates the part of
__zerocopy_sg_from_iter() charging pages to the socket. It'd be too easy
to miss while changing it in net/, the chunk is not the most
straightforward for outside users and full of internal implementation
details. io_uring is not a good place to keep it, deduplicate it by
moving out of the callback into __zerocopy_sg_from_iter().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
IORING_OP_LISTEN provides the semantic of listen(2) via io_uring. While
this is an essentially synchronous system call, the main point is to
enable a network path to execute fully with io_uring registered and
descriptorless files.
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20240614163047.31581-4-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
IORING_OP_BIND provides the semantic of bind(2) via io_uring. While
this is an essentially synchronous system call, the main point is to
enable a network path to execute fully with io_uring registered and
descriptorless files.
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://lore.kernel.org/r/20240614163047.31581-3-krisman@suse.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
syzbot reports that recv is using an uninitialized value:
=====================================================
BUG: KMSAN: uninit-value in io_req_cqe_overflow io_uring/io_uring.c:810 [inline]
BUG: KMSAN: uninit-value in io_req_complete_post io_uring/io_uring.c:937 [inline]
BUG: KMSAN: uninit-value in io_issue_sqe+0x1f1b/0x22c0 io_uring/io_uring.c:1763
io_req_cqe_overflow io_uring/io_uring.c:810 [inline]
io_req_complete_post io_uring/io_uring.c:937 [inline]
io_issue_sqe+0x1f1b/0x22c0 io_uring/io_uring.c:1763
io_wq_submit_work+0xa17/0xeb0 io_uring/io_uring.c:1860
io_worker_handle_work+0xc04/0x2000 io_uring/io-wq.c:597
io_wq_worker+0x447/0x1410 io_uring/io-wq.c:651
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was stored to memory at:
io_req_set_res io_uring/io_uring.h:215 [inline]
io_recv_finish+0xf10/0x1560 io_uring/net.c:861
io_recv+0x12ec/0x1ea0 io_uring/net.c:1175
io_issue_sqe+0x429/0x22c0 io_uring/io_uring.c:1751
io_wq_submit_work+0xa17/0xeb0 io_uring/io_uring.c:1860
io_worker_handle_work+0xc04/0x2000 io_uring/io-wq.c:597
io_wq_worker+0x447/0x1410 io_uring/io-wq.c:651
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was created at:
slab_post_alloc_hook mm/slub.c:3877 [inline]
slab_alloc_node mm/slub.c:3918 [inline]
__do_kmalloc_node mm/slub.c:4038 [inline]
__kmalloc+0x6e4/0x1060 mm/slub.c:4052
kmalloc include/linux/slab.h:632 [inline]
io_alloc_async_data+0xc0/0x220 io_uring/io_uring.c:1662
io_msg_alloc_async io_uring/net.c:166 [inline]
io_recvmsg_prep_setup io_uring/net.c:725 [inline]
io_recvmsg_prep+0xbe8/0x1a20 io_uring/net.c:806
io_init_req io_uring/io_uring.c:2135 [inline]
io_submit_sqe io_uring/io_uring.c:2182 [inline]
io_submit_sqes+0x1135/0x2f10 io_uring/io_uring.c:2335
__do_sys_io_uring_enter io_uring/io_uring.c:3246 [inline]
__se_sys_io_uring_enter+0x40f/0x3c80 io_uring/io_uring.c:3183
__x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3183
x64_sys_call+0x2c0/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:427
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
which appears to be io_recv_finish() reading kmsg->msg.msg_inq to decide
if it needs to set IORING_CQE_F_SOCK_NONEMPTY or not. If the recv is
entered with buffer selection, but no buffer is available, then we jump
error path which calls io_recv_finish() without having assigned
kmsg->msg_inq. This might cause an errant setting of the NONEMPTY flag
for a request get gets errored with -ENOBUFS.
Reported-by: syzbot+b1647099e82b3b349fbf@syzkaller.appspotmail.com
Fixes: 4a3223f7bf ("io_uring/net: switch io_recv() to using io_async_msghdr")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If the given protocol supports passing back whether or not we had more
pending accept post this one, pass back this information to userspace.
This is done by setting IORING_CQE_F_SOCK_NONEMPTY in the CQE flags,
just like we do for recv/recvmsg if there's more data available post
a receive operation.
We can also use this information to be smarter about multishot retry,
as we don't need to do a pointless retry if we know for a fact that
there aren't any more connections to accept.
Suggested-by: Norman Maurer <norman_maurer@apple.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In preparation for passing in more information via this API, change
do_accept() to take a proto_accept_arg struct pointer rather than just
the file flags separately.
No functional changes in this patch.
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Similarly to how polling first is supported for receive, it makes sense
to provide the same for accept. An accept operation does a lot of
expensive setup, like allocating an fd, a socket/inode, etc. If no
connection request is already pending, this is wasted and will just be
cleaned up and freed, only to retry via the usual poll trigger.
Add IORING_ACCEPT_POLL_FIRST, which tells accept to only initiate the
accept request if poll says we have something to accept.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This allows the caller to perform a non-blocking attempt, similarly to
how recvmsg has MSG_DONTWAIT. If set, and we get -EAGAIN on a connection
attempt, propagate the result to userspace rather than arm poll and
wait for a retry.
Suggested-by: Norman Maurer <norman_maurer@apple.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When sending from a provided buffer, we set sr->len to be the smallest
between the actual buffer size and sqe->len. But, now that we
disconnect the buffer from the submission request, we can get in a
situation where the buffers and requests mismatch, and only part of a
buffer gets sent. Assume:
* buf[1]->len = 128; buf[2]->len = 256
* sqe[1]->len = 128; sqe[2]->len = 256
If sqe1 runs first, it picks buff[1] and it's all good. But, if sqe[2]
runs first, sqe[1] picks buff[2], and the last half of buff[2] is
never sent.
While arguably the use-case of different-length sends is questionable,
it has already raised confusion with potential users of this
feature. Let's make the interface less tricky by forcing the length to
only come from the buffer ring entry itself.
Fixes: ac5f71a3d9 ("io_uring/net: add provided buffer support for IORING_OP_SEND")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
SEND[MSG]_ZC produces multiple CQEs via notifications, LAZY_WAKE doesn't
handle it and so disable LAZY_WAKE for sendzc polling. It should be
fine, sends are not likely to be polled in the first place.
Fixes: 6ce4a93dbb ("io_uring/poll: use IOU_F_TWQ_LAZY_WAKE for wakeups")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/5b360fb352d91e3aec751d75c87dfb4753a084ee.1714488419.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If IORING_OP_RECV is used with provided buffers, the caller may also set
IORING_RECVSEND_BUNDLE to turn it into a multi-buffer recv. This grabs
buffers available and receives into them, posting a single completion for
all of it.
This can be used with multishot receive as well, or without it.
Now that both send and receive support bundles, add a feature flag for
it as well. If IORING_FEAT_RECVSEND_BUNDLE is set after registering the
ring, then the kernel supports bundles for recv and send.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If IORING_OP_SEND is used with provided buffers, the caller may also
set IORING_RECVSEND_BUNDLE to turn it into a multi-buffer send. The idea
is that an application can fill outgoing buffers in a provided buffer
group, and then arm a single send that will service them all. Once
there are no more buffers to send, or if the requested length has
been sent, the request posts a single completion for all the buffers.
This only enables it for IORING_OP_SEND, IORING_OP_SENDMSG is coming
in a separate patch. However, this patch does do a lot of the prep
work that makes wiring up the sendmsg variant pretty trivial. They
share the prep side.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's pretty trivial to wire up provided buffer support for the send
side, just like how it's done the receive side. This enables setting up
a buffer ring that an application can use to push pending sends to,
and then have a send pick a buffer from that ring.
One of the challenges with async IO and networking sends is that you
can get into reordering conditions if you have more than one inflight
at the same time. Consider the following scenario where everything is
fine:
1) App queues sendA for socket1
2) App queues sendB for socket1
3) App does io_uring_submit()
4) sendA is issued, completes successfully, posts CQE
5) sendB is issued, completes successfully, posts CQE
All is fine. Requests are always issued in-order, and both complete
inline as most sends do.
However, if we're flooding socket1 with sends, the following could
also result from the same sequence:
1) App queues sendA for socket1
2) App queues sendB for socket1
3) App does io_uring_submit()
4) sendA is issued, socket1 is full, poll is armed for retry
5) Space frees up in socket1, this triggers sendA retry via task_work
6) sendB is issued, completes successfully, posts CQE
7) sendA is retried, completes successfully, posts CQE
Now we've sent sendB before sendA, which can make things unhappy. If
both sendA and sendB had been using provided buffers, then it would look
as follows instead:
1) App queues dataA for sendA, queues sendA for socket1
2) App queues dataB for sendB queues sendB for socket1
3) App does io_uring_submit()
4) sendA is issued, socket1 is full, poll is armed for retry
5) Space frees up in socket1, this triggers sendA retry via task_work
6) sendB is issued, picks first buffer (dataA), completes successfully,
posts CQE (which says "I sent dataA")
7) sendA is retried, picks first buffer (dataB), completes successfully,
posts CQE (which says "I sent dataB")
Now we've sent the data in order, and everybody is happy.
It's worth noting that this also opens the door for supporting multishot
sends, as provided buffers would be a prerequisite for that. Those can
trigger either when new buffers are added to the outgoing ring, or (if
stalled due to lack of space) when space frees up in the socket.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is just moving io_recv_prep_retry() higher up so it can get used
for sends as well, and rename it to be generically useful for both
sends and receives.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently lists are being used to manage this, but best practice is
usually to have these in an array instead as that it cheaper to manage.
Outside of that detail, games are also played with KASAN as the list
is inside the cached entry itself.
Finally, all users of this need a struct io_cache_entry embedded in
their struct, which is union'ized with something else in there that
isn't used across the free -> realloc cycle.
Get rid of all of that, and simply have it be an array. This will not
change the memory used, as we're just trading an 8-byte member entry
for the per-elem array size.
This reduces the overhead of the recycled allocations, and it reduces
the amount of code code needed to support recycling to about half of
what it currently is.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While doing that, get rid of io_async_connect and just use the generic
io_async_msghdr. Both of them have a struct sockaddr_storage in there,
and while io_async_msghdr is bigger, if the same type can be used then
the netmsg_cache can get reused for connect as well.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that iovec recycling is being done, the iovec is no longer being
freed in there. Hence the kmsg parameter is now useless.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Right now the io_async_msghdr is recycled to avoid the overhead of
allocating+freeing it for every request. But the iovec is not included,
hence that will be allocated and freed for each transfer regardless.
This commit enables recyling of the iovec between io_async_msghdr
recycles. This avoids alloc+free for each one if an iovec is used, and
on top of that, it extends the cache hot nature of msg to the iovec as
well.
Also enables KASAN for the iovec entries, so that reuse can be detected
even while they are in the cache.
The io_async_msghdr also shrinks from 376 -> 288 bytes, an 88 byte
saving (or ~23% smaller), as the fast_iovec entry is dropped from 8
entries to a single entry. There's no point keeping a big fast iovec
entry, if iovecs aren't being allocated and freed continually.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We now ONLY call io_msg_alloc_async() from inside prep handling, which
is always locked. No need for this helper anymore, or the check in
io_msg_alloc_async() on whether the ring is locked or not.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the io_async_msghdr out of the issue path and into prep handling,
e it's now done unconditionally and hence does not need to be part
of the issue path. This means any usage of io_sendrecv_prep_async() and
io_sendmsg_prep_async(), and hence the forced async setup path is now
unified with the normal prep setup.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the io_async_msghdr out of the issue path and into prep handling,
since it's now done unconditionally and hence does not need to be part
of the issue path. This reduces the footprint of the multishot fast
path of multiple invocations of ->issue() per prep, and also means that
using ->prep_async() can be dropped for recvmsg asthis is now done via
setup on the prep side.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We currently set this separately for async/sync entry, but let's just
move it to a generic pre-issue spot and eliminate the difference
between the two.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Rather than use an on-stack one and then need to allocate and copy if
async execution is required, always grab one upfront. This should be
very cheap, and potentially even have cache hotness benefits for
back-to-back send/recv requests.
For any recv type of request, this is probably a good choice in general,
as it's expected that no data is available initially. For send this is
not necessarily the case, as space in the socket buffer is expected to
be available. However, getting a cached io_async_msghdr is very cheap,
and as it should be cache hot, probably the difference here is neglible,
if any.
A nice side benefit is that io_setup_async_msg can get killed
completely, which has some nasty iovec manipulation code.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No functional changes in this patch, just in preparation for carrying
more state than what is available now, if necessary.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No functional changes in this patch, just in preparation for carrying
more state then what is being done now, if necessary. While unifying
some of this code, add a generic send setup prep handler that they can
both use.
This gets rid of some manual msghdr and sockaddr on the stack, and makes
it look a bit more like the sendmsg/recvmsg variants. Going forward, more
can get unified on top.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The restriction on multishot execution context disallowing io-wq is
driven by rules of io_fill_cqe_req_aux(), it should only be called in
the master task context, either from the syscall path or in task_work.
Since task_work now always takes the ctx lock implying
IO_URING_F_COMPLETE_DEFER, we can just assume that the function is
always called with its defer argument set to true.
Kill the argument. Also rename the function for more consistency as
"fill" in CQE related functions was usually meant for raw interfaces
only copying data into the CQ without any locking, waking the user
and other accounting "post" functions take care of.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/93423d106c33116c7d06bf277f651aa68b427328.1710799188.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we get a request with IOSQE_ASYNC set, then we first run the prep
async handlers. But if we then fail setting it up and want to post
a CQE with -EINVAL, we use ->done_io. This was previously guarded with
REQ_F_PARTIAL_IO, and the normal setup handlers do set it up before any
potential errors, but we need to cover the async setup too.
Fixes: 9817ad8589 ("io_uring/net: remove dependency on REQ_F_PARTIAL_IO for sr->done_io")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'for-6.9/io_uring-20240310' of git://git.kernel.dk/linux
Pull io_uring updates from Jens Axboe:
- Make running of task_work internal loops more fair, and unify how the
different methods deal with them (me)
- Support for per-ring NAPI. The two minor networking patches are in a
shared branch with netdev (Stefan)
- Add support for truncate (Tony)
- Export SQPOLL utilization stats (Xiaobing)
- Multishot fixes (Pavel)
- Fix for a race in manipulating the request flags via poll (Pavel)
- Cleanup the multishot checking by making it generic, moving it out of
opcode handlers (Pavel)
- Various tweaks and cleanups (me, Kunwu, Alexander)
* tag 'for-6.9/io_uring-20240310' of git://git.kernel.dk/linux: (53 commits)
io_uring: Fix sqpoll utilization check racing with dying sqpoll
io_uring/net: dedup io_recv_finish req completion
io_uring: refactor DEFER_TASKRUN multishot checks
io_uring: fix mshot io-wq checks
io_uring/net: add io_req_msg_cleanup() helper
io_uring/net: simplify msghd->msg_inq checking
io_uring/kbuf: rename REQ_F_PARTIAL_IO to REQ_F_BL_NO_RECYCLE
io_uring/net: remove dependency on REQ_F_PARTIAL_IO for sr->done_io
io_uring/net: correctly handle multishot recvmsg retry setup
io_uring/net: clear REQ_F_BL_EMPTY in the multishot retry handler
io_uring: fix io_queue_proc modifying req->flags
io_uring: fix mshot read defer taskrun cqe posting
io_uring/net: fix overflow check in io_recvmsg_mshot_prep()
io_uring/net: correct the type of variable
io_uring/sqpoll: statistics of the true utilization of sq threads
io_uring/net: move recv/recvmsg flags out of retry loop
io_uring/kbuf: flag request if buffer pool is empty after buffer pick
io_uring/net: improve the usercopy for sendmsg/recvmsg
io_uring/net: move receive multishot out of the generic msghdr path
io_uring/net: unify how recvmsg and sendmsg copy in the msghdr
...
We disallow DEFER_TASKRUN multishots from running by io-wq, which is
checked by individual opcodes in the issue path. We can consolidate all
it in io_wq_submit_work() at the same time moving the checks out of the
hot path.
Suggested-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e492f0f11588bb5aa11d7d24e6f53b7c7628afdb.1709905727.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When checking for concurrent CQE posting, we're not only interested in
requests running from the poll handler but also strayed requests ended
up in normal io-wq execution. We're disallowing multishots in general
from io-wq, not only when they came in a certain way.
Cc: stable@vger.kernel.org
Fixes: 17add5cea2 ("io_uring: force multishot CQEs into task context")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d8c5b36a39258036f93301cd60d3cd295e40653d.1709905727.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For the fast inline path, we manually recycle the io_async_msghdr and
free the iovec, and then clear the REQ_F_NEED_CLEANUP flag to avoid
that needing doing in the slower path. We already do that in 2 spots, and
in preparation for adding more, add a helper and use it.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Just check for larger than zero rather than check for non-zero and
not -1. This is easier to read, and also protects against any errants
< 0 values that aren't -1.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We only use the flag for this purpose, so rename it accordingly. This
further prevents various other use cases of it, keeping it clean and
consistent. Then we can also check it in one spot, when it's being
attempted recycled, and remove some dead code in io_kbuf_recycle_ring().
Signed-off-by: Jens Axboe <axboe@kernel.dk>