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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 /arch/sh/kernel/hw_breakpoint.c
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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 'arch/sh/kernel/hw_breakpoint.c')
-rw-r--r--arch/sh/kernel/hw_breakpoint.c408
1 files changed, 408 insertions, 0 deletions
diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c
new file mode 100644
index 000000000..f10d64311
--- /dev/null
+++ b/arch/sh/kernel/hw_breakpoint.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/kernel/hw_breakpoint.c
+ *
+ * Unified kernel/user-space hardware breakpoint facility for the on-chip UBC.
+ *
+ * Copyright (C) 2009 - 2010 Paul Mundt
+ */
+#include <linux/init.h>
+#include <linux/perf_event.h>
+#include <linux/sched/signal.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/percpu.h>
+#include <linux/kallsyms.h>
+#include <linux/notifier.h>
+#include <linux/kprobes.h>
+#include <linux/kdebug.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <asm/hw_breakpoint.h>
+#include <asm/mmu_context.h>
+#include <asm/ptrace.h>
+#include <asm/traps.h>
+
+/*
+ * Stores the breakpoints currently in use on each breakpoint address
+ * register for each cpus
+ */
+static DEFINE_PER_CPU(struct perf_event *, bp_per_reg[HBP_NUM]);
+
+/*
+ * A dummy placeholder for early accesses until the CPUs get a chance to
+ * register their UBCs later in the boot process.
+ */
+static struct sh_ubc ubc_dummy = { .num_events = 0 };
+
+static struct sh_ubc *sh_ubc __read_mostly = &ubc_dummy;
+
+/*
+ * Install a perf counter breakpoint.
+ *
+ * We seek a free UBC channel and use it for this breakpoint.
+ *
+ * Atomic: we hold the counter->ctx->lock and we only handle variables
+ * and registers local to this cpu.
+ */
+int arch_install_hw_breakpoint(struct perf_event *bp)
+{
+ struct arch_hw_breakpoint *info = counter_arch_bp(bp);
+ int i;
+
+ for (i = 0; i < sh_ubc->num_events; i++) {
+ struct perf_event **slot = this_cpu_ptr(&bp_per_reg[i]);
+
+ if (!*slot) {
+ *slot = bp;
+ break;
+ }
+ }
+
+ if (WARN_ONCE(i == sh_ubc->num_events, "Can't find any breakpoint slot"))
+ return -EBUSY;
+
+ clk_enable(sh_ubc->clk);
+ sh_ubc->enable(info, i);
+
+ return 0;
+}
+
+/*
+ * Uninstall the breakpoint contained in the given counter.
+ *
+ * First we search the debug address register it uses and then we disable
+ * it.
+ *
+ * Atomic: we hold the counter->ctx->lock and we only handle variables
+ * and registers local to this cpu.
+ */
+void arch_uninstall_hw_breakpoint(struct perf_event *bp)
+{
+ struct arch_hw_breakpoint *info = counter_arch_bp(bp);
+ int i;
+
+ for (i = 0; i < sh_ubc->num_events; i++) {
+ struct perf_event **slot = this_cpu_ptr(&bp_per_reg[i]);
+
+ if (*slot == bp) {
+ *slot = NULL;
+ break;
+ }
+ }
+
+ if (WARN_ONCE(i == sh_ubc->num_events, "Can't find any breakpoint slot"))
+ return;
+
+ sh_ubc->disable(info, i);
+ clk_disable(sh_ubc->clk);
+}
+
+static int get_hbp_len(u16 hbp_len)
+{
+ unsigned int len_in_bytes = 0;
+
+ switch (hbp_len) {
+ case SH_BREAKPOINT_LEN_1:
+ len_in_bytes = 1;
+ break;
+ case SH_BREAKPOINT_LEN_2:
+ len_in_bytes = 2;
+ break;
+ case SH_BREAKPOINT_LEN_4:
+ len_in_bytes = 4;
+ break;
+ case SH_BREAKPOINT_LEN_8:
+ len_in_bytes = 8;
+ break;
+ }
+ return len_in_bytes;
+}
+
+/*
+ * Check for virtual address in kernel space.
+ */
+int arch_check_bp_in_kernelspace(struct arch_hw_breakpoint *hw)
+{
+ unsigned int len;
+ unsigned long va;
+
+ va = hw->address;
+ len = get_hbp_len(hw->len);
+
+ return (va >= TASK_SIZE) && ((va + len - 1) >= TASK_SIZE);
+}
+
+int arch_bp_generic_fields(int sh_len, int sh_type,
+ int *gen_len, int *gen_type)
+{
+ /* Len */
+ switch (sh_len) {
+ case SH_BREAKPOINT_LEN_1:
+ *gen_len = HW_BREAKPOINT_LEN_1;
+ break;
+ case SH_BREAKPOINT_LEN_2:
+ *gen_len = HW_BREAKPOINT_LEN_2;
+ break;
+ case SH_BREAKPOINT_LEN_4:
+ *gen_len = HW_BREAKPOINT_LEN_4;
+ break;
+ case SH_BREAKPOINT_LEN_8:
+ *gen_len = HW_BREAKPOINT_LEN_8;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* Type */
+ switch (sh_type) {
+ case SH_BREAKPOINT_READ:
+ *gen_type = HW_BREAKPOINT_R;
+ break;
+ case SH_BREAKPOINT_WRITE:
+ *gen_type = HW_BREAKPOINT_W;
+ break;
+ case SH_BREAKPOINT_RW:
+ *gen_type = HW_BREAKPOINT_W | HW_BREAKPOINT_R;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int arch_build_bp_info(struct perf_event *bp,
+ const struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
+{
+ hw->address = attr->bp_addr;
+
+ /* Len */
+ switch (attr->bp_len) {
+ case HW_BREAKPOINT_LEN_1:
+ hw->len = SH_BREAKPOINT_LEN_1;
+ break;
+ case HW_BREAKPOINT_LEN_2:
+ hw->len = SH_BREAKPOINT_LEN_2;
+ break;
+ case HW_BREAKPOINT_LEN_4:
+ hw->len = SH_BREAKPOINT_LEN_4;
+ break;
+ case HW_BREAKPOINT_LEN_8:
+ hw->len = SH_BREAKPOINT_LEN_8;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /* Type */
+ switch (attr->bp_type) {
+ case HW_BREAKPOINT_R:
+ hw->type = SH_BREAKPOINT_READ;
+ break;
+ case HW_BREAKPOINT_W:
+ hw->type = SH_BREAKPOINT_WRITE;
+ break;
+ case HW_BREAKPOINT_W | HW_BREAKPOINT_R:
+ hw->type = SH_BREAKPOINT_RW;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * Validate the arch-specific HW Breakpoint register settings
+ */
+int hw_breakpoint_arch_parse(struct perf_event *bp,
+ const struct perf_event_attr *attr,
+ struct arch_hw_breakpoint *hw)
+{
+ unsigned int align;
+ int ret;
+
+ ret = arch_build_bp_info(bp, attr, hw);
+ if (ret)
+ return ret;
+
+ ret = -EINVAL;
+
+ switch (hw->len) {
+ case SH_BREAKPOINT_LEN_1:
+ align = 0;
+ break;
+ case SH_BREAKPOINT_LEN_2:
+ align = 1;
+ break;
+ case SH_BREAKPOINT_LEN_4:
+ align = 3;
+ break;
+ case SH_BREAKPOINT_LEN_8:
+ align = 7;
+ break;
+ default:
+ return ret;
+ }
+
+ /*
+ * Check that the low-order bits of the address are appropriate
+ * for the alignment implied by len.
+ */
+ if (hw->address & align)
+ return -EINVAL;
+
+ return 0;
+}
+
+/*
+ * Release the user breakpoints used by ptrace
+ */
+void flush_ptrace_hw_breakpoint(struct task_struct *tsk)
+{
+ int i;
+ struct thread_struct *t = &tsk->thread;
+
+ for (i = 0; i < sh_ubc->num_events; i++) {
+ unregister_hw_breakpoint(t->ptrace_bps[i]);
+ t->ptrace_bps[i] = NULL;
+ }
+}
+
+static int __kprobes hw_breakpoint_handler(struct die_args *args)
+{
+ int cpu, i, rc = NOTIFY_STOP;
+ struct perf_event *bp;
+ unsigned int cmf, resume_mask;
+
+ /*
+ * Do an early return if none of the channels triggered.
+ */
+ cmf = sh_ubc->triggered_mask();
+ if (unlikely(!cmf))
+ return NOTIFY_DONE;
+
+ /*
+ * By default, resume all of the active channels.
+ */
+ resume_mask = sh_ubc->active_mask();
+
+ /*
+ * Disable breakpoints during exception handling.
+ */
+ sh_ubc->disable_all();
+
+ cpu = get_cpu();
+ for (i = 0; i < sh_ubc->num_events; i++) {
+ unsigned long event_mask = (1 << i);
+
+ if (likely(!(cmf & event_mask)))
+ continue;
+
+ /*
+ * The counter may be concurrently released but that can only
+ * occur from a call_rcu() path. We can then safely fetch
+ * the breakpoint, use its callback, touch its counter
+ * while we are in an rcu_read_lock() path.
+ */
+ rcu_read_lock();
+
+ bp = per_cpu(bp_per_reg[i], cpu);
+ if (bp)
+ rc = NOTIFY_DONE;
+
+ /*
+ * Reset the condition match flag to denote completion of
+ * exception handling.
+ */
+ sh_ubc->clear_triggered_mask(event_mask);
+
+ /*
+ * bp can be NULL due to concurrent perf counter
+ * removing.
+ */
+ if (!bp) {
+ rcu_read_unlock();
+ break;
+ }
+
+ /*
+ * Don't restore the channel if the breakpoint is from
+ * ptrace, as it always operates in one-shot mode.
+ */
+ if (bp->overflow_handler == ptrace_triggered)
+ resume_mask &= ~(1 << i);
+
+ perf_bp_event(bp, args->regs);
+
+ /* Deliver the signal to userspace */
+ if (!arch_check_bp_in_kernelspace(&bp->hw.info)) {
+ force_sig_fault(SIGTRAP, TRAP_HWBKPT,
+ (void __user *)NULL);
+ }
+
+ rcu_read_unlock();
+ }
+
+ if (cmf == 0)
+ rc = NOTIFY_DONE;
+
+ sh_ubc->enable_all(resume_mask);
+
+ put_cpu();
+
+ return rc;
+}
+
+BUILD_TRAP_HANDLER(breakpoint)
+{
+ unsigned long ex = lookup_exception_vector();
+ TRAP_HANDLER_DECL;
+
+ notify_die(DIE_BREAKPOINT, "breakpoint", regs, 0, ex, SIGTRAP);
+}
+
+/*
+ * Handle debug exception notifications.
+ */
+int __kprobes hw_breakpoint_exceptions_notify(struct notifier_block *unused,
+ unsigned long val, void *data)
+{
+ struct die_args *args = data;
+
+ if (val != DIE_BREAKPOINT)
+ return NOTIFY_DONE;
+
+ /*
+ * If the breakpoint hasn't been triggered by the UBC, it's
+ * probably from a debugger, so don't do anything more here.
+ *
+ * This also permits the UBC interface clock to remain off for
+ * non-UBC breakpoints, as we don't need to check the triggered
+ * or active channel masks.
+ */
+ if (args->trapnr != sh_ubc->trap_nr)
+ return NOTIFY_DONE;
+
+ return hw_breakpoint_handler(data);
+}
+
+void hw_breakpoint_pmu_read(struct perf_event *bp)
+{
+ /* TODO */
+}
+
+int register_sh_ubc(struct sh_ubc *ubc)
+{
+ /* Bail if it's already assigned */
+ if (sh_ubc != &ubc_dummy)
+ return -EBUSY;
+ sh_ubc = ubc;
+
+ pr_info("HW Breakpoints: %s UBC support registered\n", ubc->name);
+
+ WARN_ON(ubc->num_events > HBP_NUM);
+
+ return 0;
+}