From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ... --- arch/x86/kernel/msr.c | 333 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 333 insertions(+) create mode 100644 arch/x86/kernel/msr.c (limited to 'arch/x86/kernel/msr.c') diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c new file mode 100644 index 000000000..708751311 --- /dev/null +++ b/arch/x86/kernel/msr.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* ----------------------------------------------------------------------- * + * + * Copyright 2000-2008 H. Peter Anvin - All Rights Reserved + * Copyright 2009 Intel Corporation; author: H. Peter Anvin + * + * ----------------------------------------------------------------------- */ + +/* + * x86 MSR access device + * + * This device is accessed by lseek() to the appropriate register number + * and then read/write in chunks of 8 bytes. A larger size means multiple + * reads or writes of the same register. + * + * This driver uses /dev/cpu/%d/msr where %d is the minor number, and on + * an SMP box will direct the access to CPU %d. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +static struct class *msr_class; +static enum cpuhp_state cpuhp_msr_state; + +enum allow_write_msrs { + MSR_WRITES_ON, + MSR_WRITES_OFF, + MSR_WRITES_DEFAULT, +}; + +static enum allow_write_msrs allow_writes = MSR_WRITES_DEFAULT; + +static ssize_t msr_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + u32 __user *tmp = (u32 __user *) buf; + u32 data[2]; + u32 reg = *ppos; + int cpu = iminor(file_inode(file)); + int err = 0; + ssize_t bytes = 0; + + if (count % 8) + return -EINVAL; /* Invalid chunk size */ + + for (; count; count -= 8) { + err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]); + if (err) + break; + if (copy_to_user(tmp, &data, 8)) { + err = -EFAULT; + break; + } + tmp += 2; + bytes += 8; + } + + return bytes ? bytes : err; +} + +static int filter_write(u32 reg) +{ + /* + * MSRs writes usually happen all at once, and can easily saturate kmsg. + * Only allow one message every 30 seconds. + * + * It's possible to be smarter here and do it (for example) per-MSR, but + * it would certainly be more complex, and this is enough at least to + * avoid saturating the ring buffer. + */ + static DEFINE_RATELIMIT_STATE(fw_rs, 30 * HZ, 1); + + switch (allow_writes) { + case MSR_WRITES_ON: return 0; + case MSR_WRITES_OFF: return -EPERM; + default: break; + } + + if (!__ratelimit(&fw_rs)) + return 0; + + pr_warn("Write to unrecognized MSR 0x%x by %s (pid: %d).\n", + reg, current->comm, current->pid); + pr_warn("See https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/about for details.\n"); + + return 0; +} + +static ssize_t msr_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + const u32 __user *tmp = (const u32 __user *)buf; + u32 data[2]; + u32 reg = *ppos; + int cpu = iminor(file_inode(file)); + int err = 0; + ssize_t bytes = 0; + + err = security_locked_down(LOCKDOWN_MSR); + if (err) + return err; + + err = filter_write(reg); + if (err) + return err; + + if (count % 8) + return -EINVAL; /* Invalid chunk size */ + + for (; count; count -= 8) { + if (copy_from_user(&data, tmp, 8)) { + err = -EFAULT; + break; + } + + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); + + err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]); + if (err) + break; + + tmp += 2; + bytes += 8; + } + + return bytes ? bytes : err; +} + +static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg) +{ + u32 __user *uregs = (u32 __user *)arg; + u32 regs[8]; + int cpu = iminor(file_inode(file)); + int err; + + switch (ioc) { + case X86_IOC_RDMSR_REGS: + if (!(file->f_mode & FMODE_READ)) { + err = -EBADF; + break; + } + if (copy_from_user(®s, uregs, sizeof(regs))) { + err = -EFAULT; + break; + } + err = rdmsr_safe_regs_on_cpu(cpu, regs); + if (err) + break; + if (copy_to_user(uregs, ®s, sizeof(regs))) + err = -EFAULT; + break; + + case X86_IOC_WRMSR_REGS: + if (!(file->f_mode & FMODE_WRITE)) { + err = -EBADF; + break; + } + if (copy_from_user(®s, uregs, sizeof(regs))) { + err = -EFAULT; + break; + } + err = security_locked_down(LOCKDOWN_MSR); + if (err) + break; + + err = filter_write(regs[1]); + if (err) + return err; + + add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK); + + err = wrmsr_safe_regs_on_cpu(cpu, regs); + if (err) + break; + if (copy_to_user(uregs, ®s, sizeof(regs))) + err = -EFAULT; + break; + + default: + err = -ENOTTY; + break; + } + + return err; +} + +static int msr_open(struct inode *inode, struct file *file) +{ + unsigned int cpu = iminor(file_inode(file)); + struct cpuinfo_x86 *c; + + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + + if (cpu >= nr_cpu_ids || !cpu_online(cpu)) + return -ENXIO; /* No such CPU */ + + c = &cpu_data(cpu); + if (!cpu_has(c, X86_FEATURE_MSR)) + return -EIO; /* MSR not supported */ + + return 0; +} + +/* + * File operations we support + */ +static const struct file_operations msr_fops = { + .owner = THIS_MODULE, + .llseek = no_seek_end_llseek, + .read = msr_read, + .write = msr_write, + .open = msr_open, + .unlocked_ioctl = msr_ioctl, + .compat_ioctl = msr_ioctl, +}; + +static int msr_device_create(unsigned int cpu) +{ + struct device *dev; + + dev = device_create(msr_class, NULL, MKDEV(MSR_MAJOR, cpu), NULL, + "msr%d", cpu); + return PTR_ERR_OR_ZERO(dev); +} + +static int msr_device_destroy(unsigned int cpu) +{ + device_destroy(msr_class, MKDEV(MSR_MAJOR, cpu)); + return 0; +} + +static char *msr_devnode(const struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "cpu/%u/msr", MINOR(dev->devt)); +} + +static int __init msr_init(void) +{ + int err; + + if (__register_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr", &msr_fops)) { + pr_err("unable to get major %d for msr\n", MSR_MAJOR); + return -EBUSY; + } + msr_class = class_create(THIS_MODULE, "msr"); + if (IS_ERR(msr_class)) { + err = PTR_ERR(msr_class); + goto out_chrdev; + } + msr_class->devnode = msr_devnode; + + err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/msr:online", + msr_device_create, msr_device_destroy); + if (err < 0) + goto out_class; + cpuhp_msr_state = err; + return 0; + +out_class: + class_destroy(msr_class); +out_chrdev: + __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr"); + return err; +} +module_init(msr_init); + +static void __exit msr_exit(void) +{ + cpuhp_remove_state(cpuhp_msr_state); + class_destroy(msr_class); + __unregister_chrdev(MSR_MAJOR, 0, NR_CPUS, "cpu/msr"); +} +module_exit(msr_exit) + +static int set_allow_writes(const char *val, const struct kernel_param *cp) +{ + /* val is NUL-terminated, see kernfs_fop_write() */ + char *s = strstrip((char *)val); + + if (!strcmp(s, "on")) + allow_writes = MSR_WRITES_ON; + else if (!strcmp(s, "off")) + allow_writes = MSR_WRITES_OFF; + else + allow_writes = MSR_WRITES_DEFAULT; + + return 0; +} + +static int get_allow_writes(char *buf, const struct kernel_param *kp) +{ + const char *res; + + switch (allow_writes) { + case MSR_WRITES_ON: res = "on"; break; + case MSR_WRITES_OFF: res = "off"; break; + default: res = "default"; break; + } + + return sprintf(buf, "%s\n", res); +} + +static const struct kernel_param_ops allow_writes_ops = { + .set = set_allow_writes, + .get = get_allow_writes +}; + +module_param_cb(allow_writes, &allow_writes_ops, NULL, 0600); + +MODULE_AUTHOR("H. Peter Anvin "); +MODULE_DESCRIPTION("x86 generic MSR driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3