diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/tty/serial/kgdb_nmi.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
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().
...
Diffstat (limited to '')
-rw-r--r-- | drivers/tty/serial/kgdb_nmi.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/drivers/tty/serial/kgdb_nmi.c b/drivers/tty/serial/kgdb_nmi.c new file mode 100644 index 000000000..55c3c9db7 --- /dev/null +++ b/drivers/tty/serial/kgdb_nmi.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KGDB NMI serial console + * + * Copyright 2010 Google, Inc. + * Arve Hjønnevåg <arve@android.com> + * Colin Cross <ccross@android.com> + * Copyright 2012 Linaro Ltd. + * Anton Vorontsov <anton.vorontsov@linaro.org> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/compiler.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/atomic.h> +#include <linux/console.h> +#include <linux/tty.h> +#include <linux/tty_driver.h> +#include <linux/tty_flip.h> +#include <linux/serial_core.h> +#include <linux/interrupt.h> +#include <linux/hrtimer.h> +#include <linux/tick.h> +#include <linux/kfifo.h> +#include <linux/kgdb.h> +#include <linux/kdb.h> + +static int kgdb_nmi_knock = 1; +module_param_named(knock, kgdb_nmi_knock, int, 0600); +MODULE_PARM_DESC(knock, "if set to 1 (default), the special '$3#33' command " \ + "must be used to enter the debugger; when set to 0, " \ + "hitting return key is enough to enter the debugger; " \ + "when set to -1, the debugger is entered immediately " \ + "upon NMI"); + +static char *kgdb_nmi_magic = "$3#33"; +module_param_named(magic, kgdb_nmi_magic, charp, 0600); +MODULE_PARM_DESC(magic, "magic sequence to enter NMI debugger (default $3#33)"); + +static atomic_t kgdb_nmi_num_readers = ATOMIC_INIT(0); + +static int kgdb_nmi_console_setup(struct console *co, char *options) +{ + arch_kgdb_ops.enable_nmi(1); + + /* The NMI console uses the dbg_io_ops to issue console messages. To + * avoid duplicate messages during kdb sessions we must inform kdb's + * I/O utilities that messages sent to the console will automatically + * be displayed on the dbg_io. + */ + dbg_io_ops->cons = co; + + return 0; +} + +static void kgdb_nmi_console_write(struct console *co, const char *s, uint c) +{ + int i; + + for (i = 0; i < c; i++) + dbg_io_ops->write_char(s[i]); +} + +static struct tty_driver *kgdb_nmi_tty_driver; + +static struct tty_driver *kgdb_nmi_console_device(struct console *co, int *idx) +{ + *idx = co->index; + return kgdb_nmi_tty_driver; +} + +static struct console kgdb_nmi_console = { + .name = "ttyNMI", + .setup = kgdb_nmi_console_setup, + .write = kgdb_nmi_console_write, + .device = kgdb_nmi_console_device, + .flags = CON_PRINTBUFFER | CON_ANYTIME, + .index = -1, +}; + +/* + * This is usually the maximum rate on debug ports. We make fifo large enough + * to make copy-pasting to the terminal usable. + */ +#define KGDB_NMI_BAUD 115200 +#define KGDB_NMI_FIFO_SIZE roundup_pow_of_two(KGDB_NMI_BAUD / 8 / HZ) + +struct kgdb_nmi_tty_priv { + struct tty_port port; + struct timer_list timer; + STRUCT_KFIFO(char, KGDB_NMI_FIFO_SIZE) fifo; +}; + +static struct tty_port *kgdb_nmi_port; + +static void kgdb_tty_recv(int ch) +{ + struct kgdb_nmi_tty_priv *priv; + char c = ch; + + if (!kgdb_nmi_port || ch < 0) + return; + /* + * Can't use port->tty->driver_data as tty might be not there. Timer + * will check for tty and will get the ref, but here we don't have to + * do that, and actually, we can't: we're in NMI context, no locks are + * possible. + */ + priv = container_of(kgdb_nmi_port, struct kgdb_nmi_tty_priv, port); + kfifo_in(&priv->fifo, &c, 1); +} + +static int kgdb_nmi_poll_one_knock(void) +{ + static int n; + int c; + const char *magic = kgdb_nmi_magic; + size_t m = strlen(magic); + bool printch = false; + + c = dbg_io_ops->read_char(); + if (c == NO_POLL_CHAR) + return c; + + if (!kgdb_nmi_knock && (c == '\r' || c == '\n')) { + return 1; + } else if (c == magic[n]) { + n = (n + 1) % m; + if (!n) + return 1; + printch = true; + } else { + n = 0; + } + + if (atomic_read(&kgdb_nmi_num_readers)) { + kgdb_tty_recv(c); + return 0; + } + + if (printch) { + kdb_printf("%c", c); + return 0; + } + + kdb_printf("\r%s %s to enter the debugger> %*s", + kgdb_nmi_knock ? "Type" : "Hit", + kgdb_nmi_knock ? magic : "<return>", (int)m, ""); + while (m--) + kdb_printf("\b"); + return 0; +} + +/** + * kgdb_nmi_poll_knock - Check if it is time to enter the debugger + * + * "Serial ports are often noisy, especially when muxed over another port (we + * often use serial over the headset connector). Noise on the async command + * line just causes characters that are ignored, on a command line that blocked + * execution noise would be catastrophic." -- Colin Cross + * + * So, this function implements KGDB/KDB knocking on the serial line: we won't + * enter the debugger until we receive a known magic phrase (which is actually + * "$3#33", known as "escape to KDB" command. There is also a relaxed variant + * of knocking, i.e. just pressing the return key is enough to enter the + * debugger. And if knocking is disabled, the function always returns 1. + */ +bool kgdb_nmi_poll_knock(void) +{ + if (kgdb_nmi_knock < 0) + return true; + + while (1) { + int ret; + + ret = kgdb_nmi_poll_one_knock(); + if (ret == NO_POLL_CHAR) + return false; + else if (ret == 1) + break; + } + return true; +} + +/* + * The tasklet is cheap, it does not cause wakeups when reschedules itself, + * instead it waits for the next tick. + */ +static void kgdb_nmi_tty_receiver(struct timer_list *t) +{ + struct kgdb_nmi_tty_priv *priv = from_timer(priv, t, timer); + char ch; + + priv->timer.expires = jiffies + (HZ/100); + add_timer(&priv->timer); + + if (likely(!atomic_read(&kgdb_nmi_num_readers) || + !kfifo_len(&priv->fifo))) + return; + + while (kfifo_out(&priv->fifo, &ch, 1)) + tty_insert_flip_char(&priv->port, ch, TTY_NORMAL); + tty_flip_buffer_push(&priv->port); +} + +static int kgdb_nmi_tty_activate(struct tty_port *port, struct tty_struct *tty) +{ + struct kgdb_nmi_tty_priv *priv = + container_of(port, struct kgdb_nmi_tty_priv, port); + + kgdb_nmi_port = port; + priv->timer.expires = jiffies + (HZ/100); + add_timer(&priv->timer); + + return 0; +} + +static void kgdb_nmi_tty_shutdown(struct tty_port *port) +{ + struct kgdb_nmi_tty_priv *priv = + container_of(port, struct kgdb_nmi_tty_priv, port); + + del_timer(&priv->timer); + kgdb_nmi_port = NULL; +} + +static const struct tty_port_operations kgdb_nmi_tty_port_ops = { + .activate = kgdb_nmi_tty_activate, + .shutdown = kgdb_nmi_tty_shutdown, +}; + +static int kgdb_nmi_tty_install(struct tty_driver *drv, struct tty_struct *tty) +{ + struct kgdb_nmi_tty_priv *priv; + int ret; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + INIT_KFIFO(priv->fifo); + timer_setup(&priv->timer, kgdb_nmi_tty_receiver, 0); + tty_port_init(&priv->port); + priv->port.ops = &kgdb_nmi_tty_port_ops; + tty->driver_data = priv; + + ret = tty_port_install(&priv->port, drv, tty); + if (ret) { + pr_err("%s: can't install tty port: %d\n", __func__, ret); + goto err; + } + return 0; +err: + tty_port_destroy(&priv->port); + kfree(priv); + return ret; +} + +static void kgdb_nmi_tty_cleanup(struct tty_struct *tty) +{ + struct kgdb_nmi_tty_priv *priv = tty->driver_data; + + tty->driver_data = NULL; + tty_port_destroy(&priv->port); + kfree(priv); +} + +static int kgdb_nmi_tty_open(struct tty_struct *tty, struct file *file) +{ + struct kgdb_nmi_tty_priv *priv = tty->driver_data; + unsigned int mode = file->f_flags & O_ACCMODE; + int ret; + + ret = tty_port_open(&priv->port, tty, file); + if (!ret && (mode == O_RDONLY || mode == O_RDWR)) + atomic_inc(&kgdb_nmi_num_readers); + + return ret; +} + +static void kgdb_nmi_tty_close(struct tty_struct *tty, struct file *file) +{ + struct kgdb_nmi_tty_priv *priv = tty->driver_data; + unsigned int mode = file->f_flags & O_ACCMODE; + + if (mode == O_RDONLY || mode == O_RDWR) + atomic_dec(&kgdb_nmi_num_readers); + + tty_port_close(&priv->port, tty, file); +} + +static void kgdb_nmi_tty_hangup(struct tty_struct *tty) +{ + struct kgdb_nmi_tty_priv *priv = tty->driver_data; + + tty_port_hangup(&priv->port); +} + +static unsigned int kgdb_nmi_tty_write_room(struct tty_struct *tty) +{ + /* Actually, we can handle any amount as we use polled writes. */ + return 2048; +} + +static int kgdb_nmi_tty_write(struct tty_struct *tty, const unchar *buf, int c) +{ + int i; + + for (i = 0; i < c; i++) + dbg_io_ops->write_char(buf[i]); + return c; +} + +static const struct tty_operations kgdb_nmi_tty_ops = { + .open = kgdb_nmi_tty_open, + .close = kgdb_nmi_tty_close, + .install = kgdb_nmi_tty_install, + .cleanup = kgdb_nmi_tty_cleanup, + .hangup = kgdb_nmi_tty_hangup, + .write_room = kgdb_nmi_tty_write_room, + .write = kgdb_nmi_tty_write, +}; + +int kgdb_register_nmi_console(void) +{ + int ret; + + if (!arch_kgdb_ops.enable_nmi) + return 0; + + kgdb_nmi_tty_driver = tty_alloc_driver(1, TTY_DRIVER_REAL_RAW); + if (IS_ERR(kgdb_nmi_tty_driver)) { + pr_err("%s: cannot allocate tty\n", __func__); + return PTR_ERR(kgdb_nmi_tty_driver); + } + kgdb_nmi_tty_driver->driver_name = "ttyNMI"; + kgdb_nmi_tty_driver->name = "ttyNMI"; + kgdb_nmi_tty_driver->num = 1; + kgdb_nmi_tty_driver->type = TTY_DRIVER_TYPE_SERIAL; + kgdb_nmi_tty_driver->subtype = SERIAL_TYPE_NORMAL; + kgdb_nmi_tty_driver->init_termios = tty_std_termios; + tty_termios_encode_baud_rate(&kgdb_nmi_tty_driver->init_termios, + KGDB_NMI_BAUD, KGDB_NMI_BAUD); + tty_set_operations(kgdb_nmi_tty_driver, &kgdb_nmi_tty_ops); + + ret = tty_register_driver(kgdb_nmi_tty_driver); + if (ret) { + pr_err("%s: can't register tty driver: %d\n", __func__, ret); + goto err_drv_reg; + } + + register_console(&kgdb_nmi_console); + + return 0; +err_drv_reg: + tty_driver_kref_put(kgdb_nmi_tty_driver); + return ret; +} +EXPORT_SYMBOL_GPL(kgdb_register_nmi_console); + +int kgdb_unregister_nmi_console(void) +{ + int ret; + + if (!arch_kgdb_ops.enable_nmi) + return 0; + arch_kgdb_ops.enable_nmi(0); + + ret = unregister_console(&kgdb_nmi_console); + if (ret) + return ret; + + tty_unregister_driver(kgdb_nmi_tty_driver); + tty_driver_kref_put(kgdb_nmi_tty_driver); + + return 0; +} +EXPORT_SYMBOL_GPL(kgdb_unregister_nmi_console); |