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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /kernel/trace/trace_printk.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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--kernel/trace/trace_printk.c400
1 files changed, 400 insertions, 0 deletions
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
new file mode 100644
index 000000000..29f6e9543
--- /dev/null
+++ b/kernel/trace/trace_printk.c
@@ -0,0 +1,400 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * trace binary printk
+ *
+ * Copyright (C) 2008 Lai Jiangshan <laijs@cn.fujitsu.com>
+ *
+ */
+#include <linux/seq_file.h>
+#include <linux/security.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/ftrace.h>
+#include <linux/string.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/ctype.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "trace.h"
+
+#ifdef CONFIG_MODULES
+
+/*
+ * modules trace_printk()'s formats are autosaved in struct trace_bprintk_fmt
+ * which are queued on trace_bprintk_fmt_list.
+ */
+static LIST_HEAD(trace_bprintk_fmt_list);
+
+/* serialize accesses to trace_bprintk_fmt_list */
+static DEFINE_MUTEX(btrace_mutex);
+
+struct trace_bprintk_fmt {
+ struct list_head list;
+ const char *fmt;
+};
+
+static inline struct trace_bprintk_fmt *lookup_format(const char *fmt)
+{
+ struct trace_bprintk_fmt *pos;
+
+ if (!fmt)
+ return ERR_PTR(-EINVAL);
+
+ list_for_each_entry(pos, &trace_bprintk_fmt_list, list) {
+ if (!strcmp(pos->fmt, fmt))
+ return pos;
+ }
+ return NULL;
+}
+
+static
+void hold_module_trace_bprintk_format(const char **start, const char **end)
+{
+ const char **iter;
+ char *fmt;
+
+ /* allocate the trace_printk per cpu buffers */
+ if (start != end)
+ trace_printk_init_buffers();
+
+ mutex_lock(&btrace_mutex);
+ for (iter = start; iter < end; iter++) {
+ struct trace_bprintk_fmt *tb_fmt = lookup_format(*iter);
+ if (tb_fmt) {
+ if (!IS_ERR(tb_fmt))
+ *iter = tb_fmt->fmt;
+ continue;
+ }
+
+ fmt = NULL;
+ tb_fmt = kmalloc(sizeof(*tb_fmt), GFP_KERNEL);
+ if (tb_fmt) {
+ fmt = kmalloc(strlen(*iter) + 1, GFP_KERNEL);
+ if (fmt) {
+ list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list);
+ strcpy(fmt, *iter);
+ tb_fmt->fmt = fmt;
+ } else
+ kfree(tb_fmt);
+ }
+ *iter = fmt;
+
+ }
+ mutex_unlock(&btrace_mutex);
+}
+
+static int module_trace_bprintk_format_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ struct module *mod = data;
+ if (mod->num_trace_bprintk_fmt) {
+ const char **start = mod->trace_bprintk_fmt_start;
+ const char **end = start + mod->num_trace_bprintk_fmt;
+
+ if (val == MODULE_STATE_COMING)
+ hold_module_trace_bprintk_format(start, end);
+ }
+ return NOTIFY_OK;
+}
+
+/*
+ * The debugfs/tracing/printk_formats file maps the addresses with
+ * the ASCII formats that are used in the bprintk events in the
+ * buffer. For userspace tools to be able to decode the events from
+ * the buffer, they need to be able to map the address with the format.
+ *
+ * The addresses of the bprintk formats are in their own section
+ * __trace_printk_fmt. But for modules we copy them into a link list.
+ * The code to print the formats and their addresses passes around the
+ * address of the fmt string. If the fmt address passed into the seq
+ * functions is within the kernel core __trace_printk_fmt section, then
+ * it simply uses the next pointer in the list.
+ *
+ * When the fmt pointer is outside the kernel core __trace_printk_fmt
+ * section, then we need to read the link list pointers. The trick is
+ * we pass the address of the string to the seq function just like
+ * we do for the kernel core formats. To get back the structure that
+ * holds the format, we simply use container_of() and then go to the
+ * next format in the list.
+ */
+static const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ struct trace_bprintk_fmt *mod_fmt;
+
+ if (list_empty(&trace_bprintk_fmt_list))
+ return NULL;
+
+ /*
+ * v will point to the address of the fmt record from t_next
+ * v will be NULL from t_start.
+ * If this is the first pointer or called from start
+ * then we need to walk the list.
+ */
+ if (!v || start_index == *pos) {
+ struct trace_bprintk_fmt *p;
+
+ /* search the module list */
+ list_for_each_entry(p, &trace_bprintk_fmt_list, list) {
+ if (start_index == *pos)
+ return &p->fmt;
+ start_index++;
+ }
+ /* pos > index */
+ return NULL;
+ }
+
+ /*
+ * v points to the address of the fmt field in the mod list
+ * structure that holds the module print format.
+ */
+ mod_fmt = container_of(v, typeof(*mod_fmt), fmt);
+ if (mod_fmt->list.next == &trace_bprintk_fmt_list)
+ return NULL;
+
+ mod_fmt = container_of(mod_fmt->list.next, typeof(*mod_fmt), list);
+
+ return &mod_fmt->fmt;
+}
+
+static void format_mod_start(void)
+{
+ mutex_lock(&btrace_mutex);
+}
+
+static void format_mod_stop(void)
+{
+ mutex_unlock(&btrace_mutex);
+}
+
+#else /* !CONFIG_MODULES */
+__init static int
+module_trace_bprintk_format_notify(struct notifier_block *self,
+ unsigned long val, void *data)
+{
+ return NOTIFY_OK;
+}
+static inline const char **
+find_next_mod_format(int start_index, void *v, const char **fmt, loff_t *pos)
+{
+ return NULL;
+}
+static inline void format_mod_start(void) { }
+static inline void format_mod_stop(void) { }
+#endif /* CONFIG_MODULES */
+
+static bool __read_mostly trace_printk_enabled = true;
+
+void trace_printk_control(bool enabled)
+{
+ trace_printk_enabled = enabled;
+}
+
+__initdata_or_module static
+struct notifier_block module_trace_bprintk_format_nb = {
+ .notifier_call = module_trace_bprintk_format_notify,
+};
+
+int __trace_bprintk(unsigned long ip, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+
+ if (unlikely(!fmt))
+ return 0;
+
+ if (!trace_printk_enabled)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = trace_vbprintk(ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__trace_bprintk);
+
+int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap)
+{
+ if (unlikely(!fmt))
+ return 0;
+
+ if (!trace_printk_enabled)
+ return 0;
+
+ return trace_vbprintk(ip, fmt, ap);
+}
+EXPORT_SYMBOL_GPL(__ftrace_vbprintk);
+
+int __trace_printk(unsigned long ip, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+
+ if (!trace_printk_enabled)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = trace_vprintk(ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(__trace_printk);
+
+int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
+{
+ if (!trace_printk_enabled)
+ return 0;
+
+ return trace_vprintk(ip, fmt, ap);
+}
+EXPORT_SYMBOL_GPL(__ftrace_vprintk);
+
+bool trace_is_tracepoint_string(const char *str)
+{
+ const char **ptr = __start___tracepoint_str;
+
+ for (ptr = __start___tracepoint_str; ptr < __stop___tracepoint_str; ptr++) {
+ if (str == *ptr)
+ return true;
+ }
+ return false;
+}
+
+static const char **find_next(void *v, loff_t *pos)
+{
+ const char **fmt = v;
+ int start_index;
+ int last_index;
+
+ start_index = __stop___trace_bprintk_fmt - __start___trace_bprintk_fmt;
+
+ if (*pos < start_index)
+ return __start___trace_bprintk_fmt + *pos;
+
+ /*
+ * The __tracepoint_str section is treated the same as the
+ * __trace_printk_fmt section. The difference is that the
+ * __trace_printk_fmt section should only be used by trace_printk()
+ * in a debugging environment, as if anything exists in that section
+ * the trace_prink() helper buffers are allocated, which would just
+ * waste space in a production environment.
+ *
+ * The __tracepoint_str sections on the other hand are used by
+ * tracepoints which need to map pointers to their strings to
+ * the ASCII text for userspace.
+ */
+ last_index = start_index;
+ start_index = __stop___tracepoint_str - __start___tracepoint_str;
+
+ if (*pos < last_index + start_index)
+ return __start___tracepoint_str + (*pos - last_index);
+
+ start_index += last_index;
+ return find_next_mod_format(start_index, v, fmt, pos);
+}
+
+static void *
+t_start(struct seq_file *m, loff_t *pos)
+{
+ format_mod_start();
+ return find_next(NULL, pos);
+}
+
+static void *t_next(struct seq_file *m, void * v, loff_t *pos)
+{
+ (*pos)++;
+ return find_next(v, pos);
+}
+
+static int t_show(struct seq_file *m, void *v)
+{
+ const char **fmt = v;
+ const char *str = *fmt;
+ int i;
+
+ if (!*fmt)
+ return 0;
+
+ seq_printf(m, "0x%lx : \"", *(unsigned long *)fmt);
+
+ /*
+ * Tabs and new lines need to be converted.
+ */
+ for (i = 0; str[i]; i++) {
+ switch (str[i]) {
+ case '\n':
+ seq_puts(m, "\\n");
+ break;
+ case '\t':
+ seq_puts(m, "\\t");
+ break;
+ case '\\':
+ seq_putc(m, '\\');
+ break;
+ case '"':
+ seq_puts(m, "\\\"");
+ break;
+ default:
+ seq_putc(m, str[i]);
+ }
+ }
+ seq_puts(m, "\"\n");
+
+ return 0;
+}
+
+static void t_stop(struct seq_file *m, void *p)
+{
+ format_mod_stop();
+}
+
+static const struct seq_operations show_format_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .show = t_show,
+ .stop = t_stop,
+};
+
+static int
+ftrace_formats_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ ret = security_locked_down(LOCKDOWN_TRACEFS);
+ if (ret)
+ return ret;
+
+ return seq_open(file, &show_format_seq_ops);
+}
+
+static const struct file_operations ftrace_formats_fops = {
+ .open = ftrace_formats_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static __init int init_trace_printk_function_export(void)
+{
+ int ret;
+
+ ret = tracing_init_dentry();
+ if (ret)
+ return 0;
+
+ trace_create_file("printk_formats", TRACE_MODE_READ, NULL,
+ NULL, &ftrace_formats_fops);
+
+ return 0;
+}
+
+fs_initcall(init_trace_printk_function_export);
+
+static __init int init_trace_printk(void)
+{
+ return register_module_notifier(&module_trace_bprintk_format_nb);
+}
+
+early_initcall(init_trace_printk);