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2025-02-20bpf: Add BPF_SOCK_OPS_TSTAMP_SND_SW_CB callbackJason Xing
Support sw SCM_TSTAMP_SND case for bpf timestamping. Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SND_SW_CB. This callback will occur at the same timestamping point as the user space's software SCM_TSTAMP_SND. The BPF program can use it to get the same SCM_TSTAMP_SND timestamp without modifying the user-space application. Based on this patch, BPF program will get the software timestamp when the driver is ready to send the skb. In the sebsequent patch, the hardware timestamp will be supported. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250220072940.99994-8-kerneljasonxing@gmail.com
2025-02-20bpf: Add BPF_SOCK_OPS_TSTAMP_SCHED_CB callbackJason Xing
Support SCM_TSTAMP_SCHED case for bpf timestamping. Add a new sock_ops callback, BPF_SOCK_OPS_TSTAMP_SCHED_CB. This callback will occur at the same timestamping point as the user space's SCM_TSTAMP_SCHED. The BPF program can use it to get the same SCM_TSTAMP_SCHED timestamp without modifying the user-space application. A new SKBTX_BPF flag is added to mark skb_shinfo(skb)->tx_flags, ensuring that the new BPF timestamping and the current user space's SO_TIMESTAMPING do not interfere with each other. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250220072940.99994-7-kerneljasonxing@gmail.com
2025-02-20bpf: Prevent unsafe access to the sock fields in the BPF timestamping callbackJason Xing
The subsequent patch will implement BPF TX timestamping. It will call the sockops BPF program without holding the sock lock. This breaks the current assumption that all sock ops programs will hold the sock lock. The sock's fields of the uapi's bpf_sock_ops requires this assumption. To address this, a new "u8 is_locked_tcp_sock;" field is added. This patch sets it in the current sock_ops callbacks. The "is_fullsock" test is then replaced by the "is_locked_tcp_sock" test during sock_ops_convert_ctx_access(). The new TX timestamping callbacks added in the subsequent patch will not have this set. This will prevent unsafe access from the new timestamping callbacks. Potentially, we could allow read-only access. However, this would require identifying which callback is read-safe-only and also requires additional BPF instruction rewrites in the covert_ctx. Since the BPF program can always read everything from a socket (e.g., by using bpf_core_cast), this patch keeps it simple and disables all read and write access to any socket fields through the bpf_sock_ops UAPI from the new TX timestamping callback. Moreover, note that some of the fields in bpf_sock_ops are specific to tcp_sock, and sock_ops currently only supports tcp_sock. In the future, UDP timestamping will be added, which will also break this assumption. The same idea used in this patch will be reused. Considering that the current sock_ops only supports tcp_sock, the variable is named is_locked_"tcp"_sock. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20250220072940.99994-4-kerneljasonxing@gmail.com
2025-02-20bpf: Prepare the sock_ops ctx and call bpf prog for TX timestampingJason Xing
This patch introduces a new bpf_skops_tx_timestamping() function that prepares the "struct bpf_sock_ops" ctx and then executes the sockops BPF program. The subsequent patch will utilize bpf_skops_tx_timestamping() at the existing TX timestamping kernel callbacks (__sk_tstamp_tx specifically) to call the sockops BPF program. Later, four callback points to report information to user space based on this patch will be introduced. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://patch.msgid.link/20250220072940.99994-3-kerneljasonxing@gmail.com
2025-02-20bpf: Add networking timestamping support to bpf_get/setsockopt()Jason Xing
The new SK_BPF_CB_FLAGS and new SK_BPF_CB_TX_TIMESTAMPING are added to bpf_get/setsockopt. The later patches will implement the BPF networking timestamping. The BPF program will use bpf_setsockopt(SK_BPF_CB_FLAGS, SK_BPF_CB_TX_TIMESTAMPING) to enable the BPF networking timestamping on a socket. Signed-off-by: Jason Xing <kerneljasonxing@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20250220072940.99994-2-kerneljasonxing@gmail.com
2025-02-20i3c: Remove the const qualifier from i2c_msg pointer in i2c_xfers APIBilly Tsai
The change is necessary to enable the use of the `i2c_get_dma_safe_msg_buf()` API, which requires a non-const `struct i2c_msg *` to operate. The `i2c_get_dma_safe_msg_buf()` function ensures safe handling of I2C messages when using DMA, making it essential for scenarios where DMA transfers are involved. By removing the `const` qualifier, this patch allows drivers to prepare and manage DMA-safe buffers directly. Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com> Reviewed-by: Frank Li <Frank.Li@nxp.com> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com> Link: https://lore.kernel.org/r/20250204091702.4014466-1-billy_tsai@aspeedtech.com Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
2025-02-20net: Add options as a flexible array to struct ip_tunnel_infoGal Pressman
Remove the hidden assumption that options are allocated at the end of the struct, and teach the compiler about them using a flexible array. With this, we can revert the unsafe_memcpy() call we have in tun_dst_unclone() [1], and resolve the false field-spanning write warning caused by the memcpy() in ip_tunnel_info_opts_set(). The layout of struct ip_tunnel_info remains the same with this patch. Before this patch, there was an implicit padding at the end of the struct, options would be written at 'info + 1' which is after the padding. This will remain the same as this patch explicitly aligns 'options'. The alignment is needed as the options are later casted to different structs, and might result in unaligned memory access. Pahole output before this patch: struct ip_tunnel_info { struct ip_tunnel_key key; /* 0 64 */ /* XXX last struct has 1 byte of padding */ /* --- cacheline 1 boundary (64 bytes) --- */ struct ip_tunnel_encap encap; /* 64 8 */ struct dst_cache dst_cache; /* 72 16 */ u8 options_len; /* 88 1 */ u8 mode; /* 89 1 */ /* size: 96, cachelines: 2, members: 5 */ /* padding: 6 */ /* paddings: 1, sum paddings: 1 */ /* last cacheline: 32 bytes */ }; Pahole output after this patch: struct ip_tunnel_info { struct ip_tunnel_key key; /* 0 64 */ /* XXX last struct has 1 byte of padding */ /* --- cacheline 1 boundary (64 bytes) --- */ struct ip_tunnel_encap encap; /* 64 8 */ struct dst_cache dst_cache; /* 72 16 */ u8 options_len; /* 88 1 */ u8 mode; /* 89 1 */ /* XXX 6 bytes hole, try to pack */ u8 options[] __attribute__((__aligned__(16))); /* 96 0 */ /* size: 96, cachelines: 2, members: 6 */ /* sum members: 90, holes: 1, sum holes: 6 */ /* paddings: 1, sum paddings: 1 */ /* forced alignments: 1, forced holes: 1, sum forced holes: 6 */ /* last cacheline: 32 bytes */ } __attribute__((__aligned__(16))); [1] Commit 13cfd6a6d7ac ("net: Silence false field-spanning write warning in metadata_dst memcpy") Link: https://lore.kernel.org/all/53D1D353-B8F6-4ADC-8F29-8C48A7C9C6F1@kernel.org/ Suggested-by: Kees Cook <kees@kernel.org> Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com> Reviewed-by: Tariq Toukan <tariqt@nvidia.com> Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://patch.msgid.link/20250219143256.370277-3-gal@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-20ip_tunnel: Use ip_tunnel_info() helper instead of 'info + 1'Gal Pressman
Tunnel options should not be accessed directly, use the ip_tunnel_info() accessor instead. Signed-off-by: Gal Pressman <gal@nvidia.com> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://patch.msgid.link/20250219143256.370277-2-gal@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.14-rc4). No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-20Merge tag 'net-6.14-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Smaller than usual with no fixes from any subtree. Current release - regressions: - core: fix race of rtnl_net_lock(dev_net(dev)) Previous releases - regressions: - core: remove the single page frag cache for good - flow_dissector: fix handling of mixed port and port-range keys - sched: cls_api: fix error handling causing NULL dereference - tcp: - adjust rcvq_space after updating scaling ratio - drop secpath at the same time as we currently drop dst - eth: gtp: suppress list corruption splat in gtp_net_exit_batch_rtnl(). Previous releases - always broken: - vsock: - fix variables initialization during resuming - for connectible sockets allow only connected - eth: - geneve: fix use-after-free in geneve_find_dev() - ibmvnic: don't reference skb after sending to VIOS" * tag 'net-6.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (34 commits) Revert "net: skb: introduce and use a single page frag cache" net: allow small head cache usage with large MAX_SKB_FRAGS values nfp: bpf: Add check for nfp_app_ctrl_msg_alloc() tcp: drop secpath at the same time as we currently drop dst net: axienet: Set mac_managed_pm arp: switch to dev_getbyhwaddr() in arp_req_set_public() net: Add non-RCU dev_getbyhwaddr() helper sctp: Fix undefined behavior in left shift operation selftests/bpf: Add a specific dst port matching flow_dissector: Fix port range key handling in BPF conversion selftests/net/forwarding: Add a test case for tc-flower of mixed port and port-range flow_dissector: Fix handling of mixed port and port-range keys geneve: Suppress list corruption splat in geneve_destroy_tunnels(). gtp: Suppress list corruption splat in gtp_net_exit_batch_rtnl(). dev: Use rtnl_net_dev_lock() in unregister_netdev(). net: Fix dev_net(dev) race in unregister_netdevice_notifier_dev_net(). net: Add net_passive_inc() and net_passive_dec(). net: pse-pd: pd692x0: Fix power limit retrieval MAINTAINERS: trim the GVE entry gve: set xdp redirect target only when it is available ...
2025-02-20leds: max77705: Add LEDs supportDzmitry Sankouski
This adds basic support for LEDs for the max77705 PMIC. Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20250123-starqltechn_integration_upstream-v17-7-8b06685b6612@gmail.com Signed-off-by: Lee Jones <lee@kernel.org>
2025-02-20mfd: Add new driver for MAX77705 PMICDzmitry Sankouski
Add the core MFD driver for max77705 PMIC. Drivers for sub-devices will be added in subsequent patches. Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Link: https://lore.kernel.org/r/20250123-starqltechn_integration_upstream-v17-5-8b06685b6612@gmail.com Signed-off-by: Lee Jones <lee@kernel.org>
2025-02-20power: supply: max77705: Add charger driver for Maxim 77705Dzmitry Sankouski
Add driver for Maxim 77705 switch-mode charger. It providing power supply class information to userspace. The driver is configured through DTS (battery and system related settings). Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> Link: https://lore.kernel.org/r/20250123-starqltechn_integration_upstream-v17-3-8b06685b6612@gmail.com Signed-off-by: Lee Jones <lee@kernel.org>
2025-02-20mfd: axp20x: AXP717: Add AXP717_TS_PIN_CFG to writeable regsChris Morgan
Add AXP717_TS_PIN_CFG (register 0x50) to the table of writeable registers so that the temperature sensor can be configured by the battery driver. Signed-off-by: Chris Morgan <macromorgan@hotmail.com> Link: https://lore.kernel.org/r/20250204155835.161973-3-macroalpha82@gmail.com Signed-off-by: Lee Jones <lee@kernel.org>
2025-02-20io_uring/epoll: add support for IORING_OP_EPOLL_WAITJens Axboe
For existing epoll event loops that can't fully convert to io_uring, the used approach is usually to add the io_uring fd to the epoll instance and use epoll_wait() to wait on both "legacy" and io_uring events. While this work, it isn't optimal as: 1) epoll_wait() is pretty limited in what it can do. It does not support partial reaping of events, or waiting on a batch of events. 2) When an io_uring ring is added to an epoll instance, it activates the io_uring "I'm being polled" logic which slows things down. Rather than use this approach, with EPOLL_WAIT support added to io_uring, event loops can use the normal io_uring wait logic for everything, as long as an epoll wait request has been armed with io_uring. Note that IORING_OP_EPOLL_WAIT does NOT take a timeout value, as this is an async request. Waiting on io_uring events in general has various timeout parameters, and those are the ones that should be used when waiting on any kind of request. If events are immediately available for reaping, then This opcode will return those immediately. If none are available, then it will post an async completion when they become available. cqe->res will contain either an error code (< 0 value) for a malformed request, invalid epoll instance, etc. It will return a positive result indicating how many events were reaped. IORING_OP_EPOLL_WAIT requests may be canceled using the normal io_uring cancelation infrastructure. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2025-02-20Merge branch 'vfs-6.15.eventpoll' of ↵Jens Axboe
https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs into for-6.15/io_uring-epoll-wait Merge epoll changes from the VFS tree, which the io_uring changes depend on. * 'vfs-6.15.eventpoll' of https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: eventpoll: add epoll_sendevents() helper eventpoll: abstract out ep_try_send_events() helper eventpoll: abstract out parameter sanity checking
2025-02-20Merge branch 'for-6.15/io_uring-rx-zc' into for-6.15/io_uring-epoll-waitJens Axboe
* for-6.15/io_uring-rx-zc: (77 commits) io_uring: Rename KConfig to Kconfig io_uring/zcrx: fix leaks on failed registration io_uring/zcrx: recheck ifq on shutdown io_uring/zcrx: add selftest net: add documentation for io_uring zcrx io_uring/zcrx: add copy fallback io_uring/zcrx: throttle receive requests io_uring/zcrx: set pp memory provider for an rx queue io_uring/zcrx: add io_recvzc request io_uring/zcrx: dma-map area for the device io_uring/zcrx: implement zerocopy receive pp memory provider io_uring/zcrx: grab a net device io_uring/zcrx: add io_zcrx_area io_uring/zcrx: add interface queue and refill queue net: add helpers for setting a memory provider on an rx queue net: page_pool: add memory provider helpers net: prepare for non devmem TCP memory providers net: page_pool: add a mp hook to unregister_netdevice* net: page_pool: add callback for mp info printing netdev: add io_uring memory provider info ...
2025-02-20Merge branch 'for-6.15/io_uring' into for-6.15/io_uring-epoll-waitJens Axboe
* for-6.15/io_uring: (30 commits) io_uring: use lockless_cq flag in io_req_complete_post() io_uring: pass struct io_tw_state by value io_uring: introduce type alias for io_tw_state io_uring/rsrc: avoid NULL check in io_put_rsrc_node() io_uring: pass ctx instead of req to io_init_req_drain() io_uring: use IO_REQ_LINK_FLAGS more io_uring/net: improve recv bundles io_uring/waitid: use generic io_cancel_remove() helper io_uring/futex: use generic io_cancel_remove() helper io_uring/cancel: add generic cancel helper io_uring/waitid: convert to io_cancel_remove_all() io_uring/futex: convert to io_cancel_remove_all() io_uring/cancel: add generic remove_all helper io_uring/kbuf: uninline __io_put_kbufs io_uring/kbuf: introduce io_kbuf_drop_legacy() io_uring/kbuf: open code __io_put_kbuf() io_uring/kbuf: remove legacy kbuf caching io_uring/kbuf: simplify __io_put_kbuf io_uring/kbuf: move locking into io_kbuf_drop() io_uring/kbuf: remove legacy kbuf kmem cache ...
2025-02-20fuse: don't truncate cached, mutated symlinkMiklos Szeredi
Fuse allows the value of a symlink to change and this property is exploited by some filesystems (e.g. CVMFS). It has been observed, that sometimes after changing the symlink contents, the value is truncated to the old size. This is caused by fuse_getattr() racing with fuse_reverse_inval_inode(). fuse_reverse_inval_inode() updates the fuse_inode's attr_version, which results in fuse_change_attributes() exiting before updating the cached attributes This is okay, as the cached attributes remain invalid and the next call to fuse_change_attributes() will likely update the inode with the correct values. The reason this causes problems is that cached symlinks will be returned through page_get_link(), which truncates the symlink to inode->i_size. This is correct for filesystems that don't mutate symlinks, but in this case it causes bad behavior. The solution is to just remove this truncation. This can cause a regression in a filesystem that relies on supplying a symlink larger than the file size, but this is unlikely. If that happens we'd need to make this behavior conditional. Reported-by: Laura Promberger <laura.promberger@cern.ch> Tested-by: Sam Lewis <samclewis@google.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Link: https://lore.kernel.org/r/20250220100258.793363-1-mszeredi@redhat.com Reviewed-by: Bernd Schubert <bschubert@ddn.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-20mei: Remove unused functionsDr. David Alan Gilbert
The following functions have been in the mei code for a long time but have never been used. mei_txe_setup_satt2() was added in 2014 by commit 32e2b59fca2c ("mei: txe: add hw-txe.c") mei_me_cl_rm_by_uuid_id() was added in 2015 by commit 79563db9ddd3 ("mei: add reference counting for me clients") mei_cldev_uuid() was added in 2015 by commit baeacd037697 ("mei: bus: export uuid and protocol version to mei_cl bus drivers") mei_cldev_recv_nonblock() was added in 2016 by commit 076802d00615 ("mei: bus: enable non-blocking RX") it is the only user of mei_cldev_recv_nonblock_vtag(). Remove them. Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Alexander Usyskin <alexander.usyskin@intel.com> Link: https://lore.kernel.org/r/20250130012654.255119-1-linux@treblig.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20genirq: Introduce irq_can_move_in_process_context()Anup Patel
Interrupt controller drivers which enable CONFIG_GENERIC_PENDING_IRQ require to know whether an interrupt can be moved in process context or not to decide whether they need to invoke the work around for non-atomic MSI updates or not. This information can be retrieved via irq_can_move_pcntxt(). That helper requires access to the top-most interrupt domain data, but the driver which requires this is usually further down in the hierarchy. Introduce irq_can_move_in_process_context() which retrieves that information from the top-most interrupt domain data. [ tglx: Massaged change log ] Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250217085657.789309-6-apatel@ventanamicro.com
2025-02-20genirq: Introduce common irq_force_complete_move() implementationThomas Gleixner
CONFIG_GENERIC_PENDING_IRQ requires an architecture specific implementation of irq_force_complete_move() for CPU hotplug. At the moment, only x86 implements this unconditionally, but for RISC-V irq_force_complete_move() is only needed when the RISC-V IMSIC driver is in use and not needed otherwise. To allow runtime configuration of this mechanism, introduce a common irq_force_complete_move() implementation in the interrupt core code, which only invokes the completion function, when a interrupt chip in the hierarchy implements it. Switch X86 over to the new mechanism. No functional change intended. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250217085657.789309-5-apatel@ventanamicro.com
2025-02-20irqchip/irq-msi-lib: Optionally set default irq_eoi()/irq_ack()Thomas Gleixner
msi_lib_init_dev_msi_info() sets the default irq_eoi()/irq_ack() callbacks unconditionally. This is correct for all existing users, but prevents the IMSIC driver to be moved to the MSI library implementation. Introduce chip_flags in struct msi_parent_ops, which instruct the library to selectively set the callbacks depending on the flags, and update all current users to set them. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Anup Patel <apatel@ventanamicro.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250217085657.789309-3-apatel@ventanamicro.com
2025-02-20driver core: Remove needless return in void API device_remove_group()Zijun Hu
Remove return since both device_remove_group() and device_remove_groups() are void functions. Fixes: e323b2dddc1c ("driver core: add device_{add|remove}_group() helpers") Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Link: https://lore.kernel.org/r/20250208-fix_device_remove_group-v1-1-8a5b0ac0ce5c@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20driver core: class: Remove needless return in void API class_remove_file()Zijun Hu
Remove return since both class_remove_file() and class_remove_file_ns() are void functions. Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Link: https://lore.kernel.org/r/20250208-cls_rmv_return-v1-1-091b37945aac@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-02-20Revert "net: skb: introduce and use a single page frag cache"Paolo Abeni
After the previous commit is finally safe to revert commit dbae2b062824 ("net: skb: introduce and use a single page frag cache"): do it here. The intended goal of such change was to counter a performance regression introduced by commit 3226b158e67c ("net: avoid 32 x truesize under-estimation for tiny skbs"). Unfortunately, the blamed commit introduces another regression for the virtio_net driver. Such a driver calls napi_alloc_skb() with a tiny size, so that the whole head frag could fit a 512-byte block. The single page frag cache uses a 1K fragment for such allocation, and the additional overhead, under small UDP packets flood, makes the page allocator a bottleneck. Thanks to commit bf9f1baa279f ("net: add dedicated kmem_cache for typical/small skb->head"), this revert does not re-introduce the original regression. Actually, in the relevant test on top of this revert, I measure a small but noticeable positive delta, just above noise level. The revert itself required some additional mangling due to recent updates in the affected code. Suggested-by: Eric Dumazet <edumazet@google.com> Fixes: dbae2b062824 ("net: skb: introduce and use a single page frag cache") Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-20net: allow small head cache usage with large MAX_SKB_FRAGS valuesPaolo Abeni
Sabrina reported the following splat: WARNING: CPU: 0 PID: 1 at net/core/dev.c:6935 netif_napi_add_weight_locked+0x8f2/0xba0 Modules linked in: CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.14.0-rc1-net-00092-g011b03359038 #996 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014 RIP: 0010:netif_napi_add_weight_locked+0x8f2/0xba0 Code: e8 c3 e6 6a fe 48 83 c4 28 5b 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc c7 44 24 10 ff ff ff ff e9 8f fb ff ff e8 9e e6 6a fe <0f> 0b e9 d3 fe ff ff e8 92 e6 6a fe 48 8b 04 24 be ff ff ff ff 48 RSP: 0000:ffffc9000001fc60 EFLAGS: 00010293 RAX: 0000000000000000 RBX: ffff88806ce48128 RCX: 1ffff11001664b9e RDX: ffff888008f00040 RSI: ffffffff8317ca42 RDI: ffff88800b325cb6 RBP: ffff88800b325c40 R08: 0000000000000001 R09: ffffed100167502c R10: ffff88800b3a8163 R11: 0000000000000000 R12: ffff88800ac1c168 R13: ffff88800ac1c168 R14: ffff88800ac1c168 R15: 0000000000000007 FS: 0000000000000000(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888008201000 CR3: 0000000004c94001 CR4: 0000000000370ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> gro_cells_init+0x1ba/0x270 xfrm_input_init+0x4b/0x2a0 xfrm_init+0x38/0x50 ip_rt_init+0x2d7/0x350 ip_init+0xf/0x20 inet_init+0x406/0x590 do_one_initcall+0x9d/0x2e0 do_initcalls+0x23b/0x280 kernel_init_freeable+0x445/0x490 kernel_init+0x20/0x1d0 ret_from_fork+0x46/0x80 ret_from_fork_asm+0x1a/0x30 </TASK> irq event stamp: 584330 hardirqs last enabled at (584338): [<ffffffff8168bf87>] __up_console_sem+0x77/0xb0 hardirqs last disabled at (584345): [<ffffffff8168bf6c>] __up_console_sem+0x5c/0xb0 softirqs last enabled at (583242): [<ffffffff833ee96d>] netlink_insert+0x14d/0x470 softirqs last disabled at (583754): [<ffffffff8317c8cd>] netif_napi_add_weight_locked+0x77d/0xba0 on kernel built with MAX_SKB_FRAGS=45, where SKB_WITH_OVERHEAD(1024) is smaller than GRO_MAX_HEAD. Such built additionally contains the revert of the single page frag cache so that napi_get_frags() ends up using the page frag allocator, triggering the splat. Note that the underlying issue is independent from the mentioned revert; address it ensuring that the small head cache will fit either TCP and GRO allocation and updating napi_alloc_skb() and __netdev_alloc_skb() to select kmalloc() usage for any allocation fitting such cache. Reported-by: Sabrina Dubroca <sd@queasysnail.net> Suggested-by: Eric Dumazet <edumazet@google.com> Fixes: 3948b05950fd ("net: introduce a config option to tweak MAX_SKB_FRAGS") Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-20Merge tag 'linux-can-next-for-6.15-20250219' of ↵Paolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next Marc Kleine-Budde says: ==================== pull-request: can-next 2025-02-19 this is a pull request of 12 patches for net-next/master. The first 4 patches are by Krzysztof Kozlowski and simplify the c_can driver's c_can_plat_probe() function. Ciprian Marian Costea contributes 3 patches to add S32G2/S32G3 support to the flexcan driver. Ruffalo Lavoisier's patch removes a duplicated word from the mcp251xfd DT bindings documentation. Oleksij Rempel extends the J1939 documentation. The next patch is by Oliver Hartkopp and adds access for the Remote Request Substitution bit in CAN-XL frames. Henrik Brix Andersen's patch for the gs_usb driver adds support for the CANnectivity firmware. The last patch is by Robin van der Gracht and removes a duplicated setup of RX FIFO in the rockchip_canfd driver. linux-can-next-for-6.15-20250219 * tag 'linux-can-next-for-6.15-20250219' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next: can: rockchip_canfd: rkcanfd_chip_fifo_setup(): remove duplicated setup of RX FIFO can: gs_usb: add VID/PID for the CANnectivity firmware can: canxl: support Remote Request Substitution bit access can: j1939: Extend stack documentation with buffer size behavior dt-binding: can: mcp251xfd: remove duplicate word can: flexcan: add NXP S32G2/S32G3 SoC support can: flexcan: Add quirk to handle separate interrupt lines for mailboxes dt-bindings: can: fsl,flexcan: add S32G2/S32G3 SoC support can: c_can: Use syscon_regmap_lookup_by_phandle_args can: c_can: Use of_property_present() to test existence of DT property can: c_can: Simplify handling syscon error path can: c_can: Drop useless final probe failure message ==================== Link: https://patch.msgid.link/20250219113354.529611-1-mkl@pengutronix.de Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-20eventpoll: add epoll_sendevents() helperJens Axboe
Basic helper that copies ready events to the specified userspace address. The event checking is quick and racy, it's up to the caller to ensure it retries appropriately in case 0 events are copied. Signed-off-by: Jens Axboe <axboe@kernel.dk> Link: https://lore.kernel.org/r/20250219172552.1565603-4-axboe@kernel.dk Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-02-20tcp: drop secpath at the same time as we currently drop dstSabrina Dubroca
Xiumei reported hitting the WARN in xfrm6_tunnel_net_exit while running tests that boil down to: - create a pair of netns - run a basic TCP test over ipcomp6 - delete the pair of netns The xfrm_state found on spi_byaddr was not deleted at the time we delete the netns, because we still have a reference on it. This lingering reference comes from a secpath (which holds a ref on the xfrm_state), which is still attached to an skb. This skb is not leaked, it ends up on sk_receive_queue and then gets defer-free'd by skb_attempt_defer_free. The problem happens when we defer freeing an skb (push it on one CPU's defer_list), and don't flush that list before the netns is deleted. In that case, we still have a reference on the xfrm_state that we don't expect at this point. We already drop the skb's dst in the TCP receive path when it's no longer needed, so let's also drop the secpath. At this point, tcp_filter has already called into the LSM hooks that may require the secpath, so it should not be needed anymore. However, in some of those places, the MPTCP extension has just been attached to the skb, so we cannot simply drop all extensions. Fixes: 68822bdf76f1 ("net: generalize skb freeing deferral to per-cpu lists") Reported-by: Xiumei Mu <xmu@redhat.com> Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/5055ba8f8f72bdcb602faa299faca73c280b7735.1739743613.git.sd@queasysnail.net Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-02-20drm/ast: cursor: Move format conversion to shared helperThomas Zimmermann
User-space cursor-image data is encoded in ARBG8888, while hardware supports ARGB4444. Implement the format conversion as part of the format-helper framework, so that other drivers can benefit. This allows to respect the damage area of the cursor update. In previous code, all cursor image data had to be converted on each update. Now, only the changed areas require an update. The hardware image is always updated completely, as it is required for the checksum update. The format-conversion helper still contains the old implementation's optimization of writing 2 output pixels at the same time. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20250217122336.230067-3-tzimmermann@suse.de
2025-02-19net: dismiss sk_forward_alloc_get()Paolo Abeni
After the previous patch we can remove the forward_alloc_get proto callback, basically reverting commit 292e6077b040 ("net: introduce sk_forward_alloc_get()") and commit 66d58f046c9d ("net: use sk_forward_alloc_get() in sk_get_meminfo()"). Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250218-net-next-mptcp-rx-path-refactor-v1-5-4a47d90d7998@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19net: Add non-RCU dev_getbyhwaddr() helperBreno Leitao
Add dedicated helper for finding devices by hardware address when holding rtnl_lock, similar to existing dev_getbyhwaddr_rcu(). This prevents PROVE_LOCKING warnings when rtnl_lock is held but RCU read lock is not. Extract common address comparison logic into dev_addr_cmp(). The context about this change could be found in the following discussion: Link: https://lore.kernel.org/all/20250206-scarlet-ermine-of-improvement-1fcac5@leitao/ Cc: kuniyu@amazon.com Cc: ushankar@purestorage.com Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250218-arm_fix_selftest-v5-1-d3d6892db9e1@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19net: stmmac: "speed" passed to fix_mac_speed is an intRussell King (Oracle)
priv->plat->fix_mac_speed() is called from stmmac_mac_link_up(), which is passed the speed as an "int". However, fix_mac_speed() implicitly casts this to an unsigned int. Some platform glue code print this value using %u, others with %d. Some implicitly cast it back to an int, and others to u32. Good practice is to use one type and only one type to represent a value being passed around a driver. Switch all of these over to consistently use "int" when dealing with a speed passed from stmmac_mac_link_up(), even though the speed will always be positive. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Chen-Yu Tsai <wens@csie.org> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Acked-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp> Link: https://patch.msgid.link/E1tkKmN-004ObM-Ge@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19ipv4: fib_rules: Add port mask matchingIdo Schimmel
Extend IPv4 FIB rules to match on source and destination ports using a mask. Note that the mask is only set when not matching on a range. Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250217134109.311176-4-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19net: fib_rules: Add port mask supportIdo Schimmel
Add support for configuring and deleting rules that match on source and destination ports using a mask as well as support for dumping such rules to user space. Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250217134109.311176-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19net: fib_rules: Add port mask attributesIdo Schimmel
Add attributes that allow matching on source and destination ports with a mask. Matching on the source port with a mask is needed in deployments where users encode path information into certain bits of the UDP source port. Temporarily set the type of the attributes to 'NLA_REJECT' while support is being added. Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250217134109.311176-2-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-02-19Merge tag 'mm-hotfixes-stable-2025-02-19-17-49' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull misc fixes from Andrew Morton: "18 hotfixes. 5 are cc:stable and the remainder address post-6.13 issues or aren't considered necessary for -stable kernels. 10 are for MM and 8 are for non-MM. All are singletons, please see the changelogs for details" * tag 'mm-hotfixes-stable-2025-02-19-17-49' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: test_xarray: fix failure in check_pause when CONFIG_XARRAY_MULTI is not defined kasan: don't call find_vm_area() in a PREEMPT_RT kernel MAINTAINERS: update Nick's contact info selftests/mm: fix check for running THP tests mm: hugetlb: avoid fallback for specific node allocation of 1G pages memcg: avoid dead loop when setting memory.max mailmap: update Nick's entry mm: pgtable: fix incorrect reclaim of non-empty PTE pages taskstats: modify taskstats version getdelays: fix error format characters mm/migrate_device: don't add folio to be freed to LRU in migrate_device_finalize() tools/mm: fix build warnings with musl-libc mailmap: add entry for Feng Tang .mailmap: add entries for Jeff Johnson mm,madvise,hugetlb: check for 0-length range after end address adjustment mm/zswap: fix inconsistency when zswap_store_page() fails lib/iov_iter: fix import_iovec_ubuf iovec management procfs: fix a locking bug in a vmcore_add_device_dump() error path
2025-02-19mm: Add copy_remote_vm_str() for readng C strings from remote VMJordan Rome
Similar to `access_process_vm()` but specific to strings. Also chunks reads by page and utilizes `strscpy()` for handling null termination. The primary motivation for this change is to copy strings from a non-current task/process in BPF. There is already a helper `bpf_copy_from_user_task()`, which uses `access_process_vm()` but one to handle strings would be very helpful. Signed-off-by: Jordan Rome <linux@jordanrome.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Link: https://lore.kernel.org/bpf/20250213152125.1837400-1-linux@jordanrome.com
2025-02-20power: supply: bq27xxx: Add voltage_max_design property for bq270x0 and bq27x10Sicelo A. Mhlongo
Report VOLTAGE_MAX_DESIGN for the bq27x00 and bq27x10 fuel gauges. Per the datasheet, this value is stored in the Charge Termination Voltage Settings (QV0 and QV1) of the Pack Configuration register. Tested on the Nokia N900 with bq27200. Signed-off-by: Sicelo A. Mhlongo <absicsz@gmail.com> Link: https://lore.kernel.org/r/20250207211521.103357-1-absicsz@gmail.com Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
2025-02-19SUNRPC: Prevent looping due to rpc_signal_task() racesTrond Myklebust
If rpc_signal_task() is called while a task is in an rpc_call_done() callback function, and the latter calls rpc_restart_call(), the task can end up looping due to the RPC_TASK_SIGNALLED flag being set without the tk_rpc_status being set. Removing the redundant mechanism for signalling the task fixes the looping behaviour. Reported-by: Li Lingfeng <lilingfeng3@huawei.com> Fixes: 39494194f93b ("SUNRPC: Fix races with rpc_killall_tasks()") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2025-02-19drm/bridge: Pass full state to atomic_post_disableMaxime Ripard
It's pretty inconvenient to access the full atomic state from drm_bridges, so let's change the atomic_post_disable hook prototype to pass it directly. Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20250213-bridge-connector-v3-5-e71598f49c8f@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2025-02-19drm/bridge: Pass full state to atomic_disableMaxime Ripard
It's pretty inconvenient to access the full atomic state from drm_bridges, so let's change the atomic_disable hook prototype to pass it directly. Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20250213-bridge-connector-v3-4-e71598f49c8f@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2025-02-19drm/bridge: Pass full state to atomic_enableMaxime Ripard
It's pretty inconvenient to access the full atomic state from drm_bridges, so let's change the atomic_enable hook prototype to pass it directly. Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20250213-bridge-connector-v3-3-e71598f49c8f@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2025-02-19drm/bridge: Pass full state to atomic_pre_enableMaxime Ripard
It's pretty inconvenient to access the full atomic state from drm_bridges, so let's change the atomic_pre_enable hook prototype to pass it directly. Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Tested-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20250213-bridge-connector-v3-2-e71598f49c8f@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2025-02-19drm/atomic: Document history of drm_atomic_stateMaxime Ripard
After some discussions on the mailing-list for an earlier revision of the series, it was suggested to document the evolution of drm_atomic_state and its use by drivers to explain some of the confusion one might still encounter when reading the framework code. Suggested-by: Simona Vetter <simona.vetter@ffwll.ch> Link: https://lore.kernel.org/dri-devel/Z4jtKHY4qN3RNZNG@phenom.ffwll.local/ Reviewed-by: Simona Vetter <simona.vetter@ffwll.ch> Link: https://lore.kernel.org/r/20250213-bridge-connector-v3-1-e71598f49c8f@kernel.org Signed-off-by: Maxime Ripard <mripard@kernel.org>
2025-02-19PM: sleep: Use DPM_FLAG_SMART_SUSPEND conditionallyRafael J. Wysocki
A recent discussion has revealed that using DPM_FLAG_SMART_SUSPEND unconditionally is generally problematic because it may lead to situations in which the device's runtime PM information is internally inconsistent or does not reflect its real state [1]. For this reason, change the handling of DPM_FLAG_SMART_SUSPEND so that it is only taken into account if it is consistently set by the drivers of all devices having any PM callbacks throughout dependency graphs in accordance with the following rules: - The "smart suspend" feature is only enabled for devices whose drivers ask for it (that is, set DPM_FLAG_SMART_SUSPEND) and for devices without PM callbacks unless they have never had runtime PM enabled. - The "smart suspend" feature is not enabled for a device if it has not been enabled for the device's parent unless the parent does not take children into account or it has never had runtime PM enabled. - The "smart suspend" feature is not enabled for a device if it has not been enabled for one of the device's suppliers taking runtime PM into account unless that supplier has never had runtime PM enabled. Namely, introduce a new device PM flag called smart_suspend that is only set if the above conditions are met and update all DPM_FLAG_SMART_SUSPEND users to check power.smart_suspend instead of directly checking the latter. At the same time, drop the power.set_active flage introduced recently in commit 3775fc538f53 ("PM: sleep: core: Synchronize runtime PM status of parents and children") because it is now sufficient to check power.smart_suspend along with the dev_pm_skip_resume() return value to decide whether or not pm_runtime_set_active() needs to be called for the device. Link: https://lore.kernel.org/linux-pm/CAPDyKFroyU3YDSfw_Y6k3giVfajg3NQGwNWeteJWqpW29BojhQ@mail.gmail.com/ [1] Fixes: 7585946243d6 ("PM: sleep: core: Restrict power.set_active propagation") Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> # drivers/pci Link: https://patch.msgid.link/1914558.tdWV9SEqCh@rjwysocki.net
2025-02-19can: canxl: support Remote Request Substitution bit accessOliver Hartkopp
The Remote Request Substitution bit is a dominant bit ("0") in the CAN XL frame. As some CAN XL controllers support to access this bit a new CANXL_RRS value has been defined for the canxl_frame.flags element. Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20250124142347.7444-1-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2025-02-18bpf: fix env->peak_states computationEduard Zingerman
Compute env->peak_states as a maximum value of sum of env->explored_states and env->free_list size. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-11-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2025-02-18bpf: free verifier states when they are no longer referencedEduard Zingerman
When fixes from patches 1 and 3 are applied, Patrick Somaru reported an increase in memory consumption for sched_ext iterator-based programs hitting 1M instructions limit. For example, 2Gb VMs ran out of memory while verifying a program. Similar behaviour could be reproduced on current bpf-next master. Here is an example of such program: /* verification completes if given 16G or RAM, * final env->free_list size is 369,960 entries. */ SEC("raw_tp") __flag(BPF_F_TEST_STATE_FREQ) __success int free_list_bomb(const void *ctx) { volatile char buf[48] = {}; unsigned i, j; j = 0; bpf_for(i, 0, 10) { /* this forks verifier state: * - verification of current path continues and * creates a checkpoint after 'if'; * - verification of forked path hits the * checkpoint and marks it as loop_entry. */ if (bpf_get_prandom_u32()) asm volatile (""); /* this marks 'j' as precise, thus any checkpoint * created on current iteration would not be matched * on the next iteration. */ buf[j++] = 42; j %= ARRAY_SIZE(buf); } asm volatile (""::"r"(buf)); return 0; } Memory consumption increased due to more states being marked as loop entries and eventually added to env->free_list. This commit introduces logic to free states from env->free_list during verification. A state in env->free_list can be freed if: - it has no child states; - it is not used as a loop_entry. This commit: - updates bpf_verifier_state->used_as_loop_entry to be a counter that tracks how many states use this one as a loop entry; - adds a function maybe_free_verifier_state(), which: - frees a state if its ->branches and ->used_as_loop_entry counters are both zero; - if the state is freed, state->loop_entry->used_as_loop_entry is decremented, and an attempt is made to free state->loop_entry. In the example above, this approach reduces the maximum number of states in the free list from 369,960 to 16,223. However, this approach has its limitations. If the buf size in the example above is modified to 64, state caching overflows: the state for j=0 is evicted from the cache before it can be used to stop traversal. As a result, states in the free list accumulate because their branch counters do not reach zero. The effect of this patch on the selftests looks as follows: File Program Max free list (A) Max free list (B) Max free list (DIFF) -------------------------------- ------------------------------------ ----------------- ----------------- -------------------- arena_list.bpf.o arena_list_add 17 3 -14 (-82.35%) bpf_iter_task_stack.bpf.o dump_task_stack 39 9 -30 (-76.92%) iters.bpf.o checkpoint_states_deletion 265 89 -176 (-66.42%) iters.bpf.o clean_live_states 19 0 -19 (-100.00%) profiler2.bpf.o tracepoint__syscalls__sys_enter_kill 102 1 -101 (-99.02%) profiler3.bpf.o tracepoint__syscalls__sys_enter_kill 144 0 -144 (-100.00%) pyperf600_iter.bpf.o on_event 15 0 -15 (-100.00%) pyperf600_nounroll.bpf.o on_event 1170 1158 -12 (-1.03%) setget_sockopt.bpf.o skops_sockopt 18 0 -18 (-100.00%) strobemeta_nounroll1.bpf.o on_event 147 83 -64 (-43.54%) strobemeta_nounroll2.bpf.o on_event 312 209 -103 (-33.01%) strobemeta_subprogs.bpf.o on_event 124 86 -38 (-30.65%) test_cls_redirect_subprogs.bpf.o cls_redirect 15 0 -15 (-100.00%) timer.bpf.o test1 30 15 -15 (-50.00%) Measured using "do-not-submit" patches from here: https://github.com/eddyz87/bpf/tree/get-loop-entry-hungup Reported-by: Patrick Somaru <patsomaru@meta.com> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20250215110411.3236773-10-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>