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().
  ...

11 files changed, 1062 insertions, 0 deletions

diff --git a/arch/riscv/kernel/probes/Makefile b/arch/riscv/kernel/probes/Makefile
new file mode 100644
index 000000000..c40139e9c
--- /dev/null
+++ b/arch/riscv/kernel/probes/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_KPROBES)		+= kprobes.o decode-insn.o simulate-insn.o
+obj-$(CONFIG_RETHOOK)		+= rethook.o rethook_trampoline.o
+obj-$(CONFIG_KPROBES_ON_FTRACE)	+= ftrace.o
+obj-$(CONFIG_UPROBES)		+= uprobes.o decode-insn.o simulate-insn.o
+CFLAGS_REMOVE_simulate-insn.o = $(CC_FLAGS_FTRACE)
diff --git a/arch/riscv/kernel/probes/decode-insn.c b/arch/riscv/kernel/probes/decode-insn.c
new file mode 100644
index 000000000..64f6183b4
--- /dev/null
+++ b/arch/riscv/kernel/probes/decode-insn.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/kernel.h>
+#include <linux/kprobes.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <asm/sections.h>
+
+#include "decode-insn.h"
+#include "simulate-insn.h"
+
+/* Return:
+ *   INSN_REJECTED     If instruction is one not allowed to kprobe,
+ *   INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
+ */
+enum probe_insn __kprobes
+riscv_probe_decode_insn(probe_opcode_t *addr, struct arch_probe_insn *api)
+{
+	probe_opcode_t insn = *addr;
+
+	/*
+	 * Reject instructions list:
+	 */
+	RISCV_INSN_REJECTED(system,		insn);
+	RISCV_INSN_REJECTED(fence,		insn);
+
+	/*
+	 * Simulate instructions list:
+	 * TODO: the REJECTED ones below need to be implemented
+	 */
+#ifdef CONFIG_RISCV_ISA_C
+	RISCV_INSN_REJECTED(c_j,		insn);
+	RISCV_INSN_REJECTED(c_jr,		insn);
+	RISCV_INSN_REJECTED(c_jal,		insn);
+	RISCV_INSN_REJECTED(c_jalr,		insn);
+	RISCV_INSN_REJECTED(c_beqz,		insn);
+	RISCV_INSN_REJECTED(c_bnez,		insn);
+	RISCV_INSN_REJECTED(c_ebreak,		insn);
+#endif
+
+	RISCV_INSN_SET_SIMULATE(jal,		insn);
+	RISCV_INSN_SET_SIMULATE(jalr,		insn);
+	RISCV_INSN_SET_SIMULATE(auipc,		insn);
+	RISCV_INSN_SET_SIMULATE(branch,		insn);
+
+	return INSN_GOOD;
+}
diff --git a/arch/riscv/kernel/probes/decode-insn.h b/arch/riscv/kernel/probes/decode-insn.h
new file mode 100644
index 000000000..42269a7d6
--- /dev/null
+++ b/arch/riscv/kernel/probes/decode-insn.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _RISCV_KERNEL_KPROBES_DECODE_INSN_H
+#define _RISCV_KERNEL_KPROBES_DECODE_INSN_H
+
+#include <asm/sections.h>
+#include <asm/kprobes.h>
+
+enum probe_insn {
+	INSN_REJECTED,
+	INSN_GOOD_NO_SLOT,
+	INSN_GOOD,
+};
+
+enum probe_insn __kprobes
+riscv_probe_decode_insn(probe_opcode_t *addr, struct arch_probe_insn *asi);
+
+#endif /* _RISCV_KERNEL_KPROBES_DECODE_INSN_H */
diff --git a/arch/riscv/kernel/probes/ftrace.c b/arch/riscv/kernel/probes/ftrace.c
new file mode 100644
index 000000000..7142ec42e
--- /dev/null
+++ b/arch/riscv/kernel/probes/ftrace.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kprobes.h>
+
+/* Ftrace callback handler for kprobes -- called under preepmt disabled */
+void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
+			   struct ftrace_ops *ops, struct ftrace_regs *fregs)
+{
+	struct kprobe *p;
+	struct pt_regs *regs;
+	struct kprobe_ctlblk *kcb;
+	int bit;
+
+	bit = ftrace_test_recursion_trylock(ip, parent_ip);
+	if (bit < 0)
+		return;
+
+	p = get_kprobe((kprobe_opcode_t *)ip);
+	if (unlikely(!p) || kprobe_disabled(p))
+		goto out;
+
+	regs = ftrace_get_regs(fregs);
+	kcb = get_kprobe_ctlblk();
+	if (kprobe_running()) {
+		kprobes_inc_nmissed_count(p);
+	} else {
+		unsigned long orig_ip = instruction_pointer(regs);
+
+		instruction_pointer_set(regs, ip);
+
+		__this_cpu_write(current_kprobe, p);
+		kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+		if (!p->pre_handler || !p->pre_handler(p, regs)) {
+			/*
+			 * Emulate singlestep (and also recover regs->pc)
+			 * as if there is a nop
+			 */
+			instruction_pointer_set(regs,
+				(unsigned long)p->addr + MCOUNT_INSN_SIZE);
+			if (unlikely(p->post_handler)) {
+				kcb->kprobe_status = KPROBE_HIT_SSDONE;
+				p->post_handler(p, regs, 0);
+			}
+			instruction_pointer_set(regs, orig_ip);
+		}
+
+		/*
+		 * If pre_handler returns !0, it changes regs->pc. We have to
+		 * skip emulating post_handler.
+		 */
+		__this_cpu_write(current_kprobe, NULL);
+	}
+out:
+	ftrace_test_recursion_unlock(bit);
+}
+NOKPROBE_SYMBOL(kprobe_ftrace_handler);
+
+int arch_prepare_kprobe_ftrace(struct kprobe *p)
+{
+	p->ainsn.api.insn = NULL;
+	return 0;
+}
diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c
new file mode 100644
index 000000000..2f08c14a9
--- /dev/null
+++ b/arch/riscv/kernel/probes/kprobes.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#define pr_fmt(fmt) "kprobes: " fmt
+
+#include <linux/kprobes.h>
+#include <linux/extable.h>
+#include <linux/slab.h>
+#include <linux/stop_machine.h>
+#include <asm/ptrace.h>
+#include <linux/uaccess.h>
+#include <asm/sections.h>
+#include <asm/cacheflush.h>
+#include <asm/bug.h>
+#include <asm/patch.h>
+
+#include "decode-insn.h"
+
+DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
+DEFINE_PER_CPU(struct kprobe_ctlblk, kprobe_ctlblk);
+
+static void __kprobes
+post_kprobe_handler(struct kprobe *, struct kprobe_ctlblk *, struct pt_regs *);
+
+static void __kprobes arch_prepare_ss_slot(struct kprobe *p)
+{
+	u32 insn = __BUG_INSN_32;
+	unsigned long offset = GET_INSN_LENGTH(p->opcode);
+
+	p->ainsn.api.restore = (unsigned long)p->addr + offset;
+
+	patch_text(p->ainsn.api.insn, &p->opcode, 1);
+	patch_text((void *)((unsigned long)(p->ainsn.api.insn) + offset),
+		   &insn, 1);
+}
+
+static void __kprobes arch_prepare_simulate(struct kprobe *p)
+{
+	p->ainsn.api.restore = 0;
+}
+
+static void __kprobes arch_simulate_insn(struct kprobe *p, struct pt_regs *regs)
+{
+	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+	if (p->ainsn.api.handler)
+		p->ainsn.api.handler((u32)p->opcode,
+					(unsigned long)p->addr, regs);
+
+	post_kprobe_handler(p, kcb, regs);
+}
+
+static bool __kprobes arch_check_kprobe(struct kprobe *p)
+{
+	unsigned long tmp  = (unsigned long)p->addr - p->offset;
+	unsigned long addr = (unsigned long)p->addr;
+
+	while (tmp <= addr) {
+		if (tmp == addr)
+			return true;
+
+		tmp += GET_INSN_LENGTH(*(u16 *)tmp);
+	}
+
+	return false;
+}
+
+int __kprobes arch_prepare_kprobe(struct kprobe *p)
+{
+	u16 *insn = (u16 *)p->addr;
+
+	if ((unsigned long)insn & 0x1)
+		return -EILSEQ;
+
+	if (!arch_check_kprobe(p))
+		return -EILSEQ;
+
+	/* copy instruction */
+	p->opcode = (kprobe_opcode_t)(*insn++);
+	if (GET_INSN_LENGTH(p->opcode) == 4)
+		p->opcode |= (kprobe_opcode_t)(*insn) << 16;
+
+	/* decode instruction */
+	switch (riscv_probe_decode_insn(p->addr, &p->ainsn.api)) {
+	case INSN_REJECTED:	/* insn not supported */
+		return -EINVAL;
+
+	case INSN_GOOD_NO_SLOT:	/* insn need simulation */
+		p->ainsn.api.insn = NULL;
+		break;
+
+	case INSN_GOOD:	/* instruction uses slot */
+		p->ainsn.api.insn = get_insn_slot();
+		if (!p->ainsn.api.insn)
+			return -ENOMEM;
+		break;
+	}
+
+	/* prepare the instruction */
+	if (p->ainsn.api.insn)
+		arch_prepare_ss_slot(p);
+	else
+		arch_prepare_simulate(p);
+
+	return 0;
+}
+
+#ifdef CONFIG_MMU
+void *alloc_insn_page(void)
+{
+	return  __vmalloc_node_range(PAGE_SIZE, 1, VMALLOC_START, VMALLOC_END,
+				     GFP_KERNEL, PAGE_KERNEL_READ_EXEC,
+				     VM_FLUSH_RESET_PERMS, NUMA_NO_NODE,
+				     __builtin_return_address(0));
+}
+#endif
+
+/* install breakpoint in text */
+void __kprobes arch_arm_kprobe(struct kprobe *p)
+{
+	u32 insn = (p->opcode & __INSN_LENGTH_MASK) == __INSN_LENGTH_32 ?
+		   __BUG_INSN_32 : __BUG_INSN_16;
+
+	patch_text(p->addr, &insn, 1);
+}
+
+/* remove breakpoint from text */
+void __kprobes arch_disarm_kprobe(struct kprobe *p)
+{
+	patch_text(p->addr, &p->opcode, 1);
+}
+
+void __kprobes arch_remove_kprobe(struct kprobe *p)
+{
+}
+
+static void __kprobes save_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+	kcb->prev_kprobe.kp = kprobe_running();
+	kcb->prev_kprobe.status = kcb->kprobe_status;
+}
+
+static void __kprobes restore_previous_kprobe(struct kprobe_ctlblk *kcb)
+{
+	__this_cpu_write(current_kprobe, kcb->prev_kprobe.kp);
+	kcb->kprobe_status = kcb->prev_kprobe.status;
+}
+
+static void __kprobes set_current_kprobe(struct kprobe *p)
+{
+	__this_cpu_write(current_kprobe, p);
+}
+
+/*
+ * Interrupts need to be disabled before single-step mode is set, and not
+ * reenabled until after single-step mode ends.
+ * Without disabling interrupt on local CPU, there is a chance of
+ * interrupt occurrence in the period of exception return and  start of
+ * out-of-line single-step, that result in wrongly single stepping
+ * into the interrupt handler.
+ */
+static void __kprobes kprobes_save_local_irqflag(struct kprobe_ctlblk *kcb,
+						struct pt_regs *regs)
+{
+	kcb->saved_status = regs->status;
+	regs->status &= ~SR_SPIE;
+}
+
+static void __kprobes kprobes_restore_local_irqflag(struct kprobe_ctlblk *kcb,
+						struct pt_regs *regs)
+{
+	regs->status = kcb->saved_status;
+}
+
+static void __kprobes setup_singlestep(struct kprobe *p,
+				       struct pt_regs *regs,
+				       struct kprobe_ctlblk *kcb, int reenter)
+{
+	unsigned long slot;
+
+	if (reenter) {
+		save_previous_kprobe(kcb);
+		set_current_kprobe(p);
+		kcb->kprobe_status = KPROBE_REENTER;
+	} else {
+		kcb->kprobe_status = KPROBE_HIT_SS;
+	}
+
+	if (p->ainsn.api.insn) {
+		/* prepare for single stepping */
+		slot = (unsigned long)p->ainsn.api.insn;
+
+		/* IRQs and single stepping do not mix well. */
+		kprobes_save_local_irqflag(kcb, regs);
+
+		instruction_pointer_set(regs, slot);
+	} else {
+		/* insn simulation */
+		arch_simulate_insn(p, regs);
+	}
+}
+
+static int __kprobes reenter_kprobe(struct kprobe *p,
+				    struct pt_regs *regs,
+				    struct kprobe_ctlblk *kcb)
+{
+	switch (kcb->kprobe_status) {
+	case KPROBE_HIT_SSDONE:
+	case KPROBE_HIT_ACTIVE:
+		kprobes_inc_nmissed_count(p);
+		setup_singlestep(p, regs, kcb, 1);
+		break;
+	case KPROBE_HIT_SS:
+	case KPROBE_REENTER:
+		pr_warn("Failed to recover from reentered kprobes.\n");
+		dump_kprobe(p);
+		BUG();
+		break;
+	default:
+		WARN_ON(1);
+		return 0;
+	}
+
+	return 1;
+}
+
+static void __kprobes
+post_kprobe_handler(struct kprobe *cur, struct kprobe_ctlblk *kcb, struct pt_regs *regs)
+{
+	/* return addr restore if non-branching insn */
+	if (cur->ainsn.api.restore != 0)
+		regs->epc = cur->ainsn.api.restore;
+
+	/* restore back original saved kprobe variables and continue */
+	if (kcb->kprobe_status == KPROBE_REENTER) {
+		restore_previous_kprobe(kcb);
+		return;
+	}
+
+	/* call post handler */
+	kcb->kprobe_status = KPROBE_HIT_SSDONE;
+	if (cur->post_handler)	{
+		/* post_handler can hit breakpoint and single step
+		 * again, so we enable D-flag for recursive exception.
+		 */
+		cur->post_handler(cur, regs, 0);
+	}
+
+	reset_current_kprobe();
+}
+
+int __kprobes kprobe_fault_handler(struct pt_regs *regs, unsigned int trapnr)
+{
+	struct kprobe *cur = kprobe_running();
+	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+
+	switch (kcb->kprobe_status) {
+	case KPROBE_HIT_SS:
+	case KPROBE_REENTER:
+		/*
+		 * We are here because the instruction being single
+		 * stepped caused a page fault. We reset the current
+		 * kprobe and the ip points back to the probe address
+		 * and allow the page fault handler to continue as a
+		 * normal page fault.
+		 */
+		regs->epc = (unsigned long) cur->addr;
+		BUG_ON(!instruction_pointer(regs));
+
+		if (kcb->kprobe_status == KPROBE_REENTER)
+			restore_previous_kprobe(kcb);
+		else {
+			kprobes_restore_local_irqflag(kcb, regs);
+			reset_current_kprobe();
+		}
+
+		break;
+	case KPROBE_HIT_ACTIVE:
+	case KPROBE_HIT_SSDONE:
+		/*
+		 * In case the user-specified fault handler returned
+		 * zero, try to fix up.
+		 */
+		if (fixup_exception(regs))
+			return 1;
+	}
+	return 0;
+}
+
+bool __kprobes
+kprobe_breakpoint_handler(struct pt_regs *regs)
+{
+	struct kprobe *p, *cur_kprobe;
+	struct kprobe_ctlblk *kcb;
+	unsigned long addr = instruction_pointer(regs);
+
+	kcb = get_kprobe_ctlblk();
+	cur_kprobe = kprobe_running();
+
+	p = get_kprobe((kprobe_opcode_t *) addr);
+
+	if (p) {
+		if (cur_kprobe) {
+			if (reenter_kprobe(p, regs, kcb))
+				return true;
+		} else {
+			/* Probe hit */
+			set_current_kprobe(p);
+			kcb->kprobe_status = KPROBE_HIT_ACTIVE;
+
+			/*
+			 * If we have no pre-handler or it returned 0, we
+			 * continue with normal processing.  If we have a
+			 * pre-handler and it returned non-zero, it will
+			 * modify the execution path and no need to single
+			 * stepping. Let's just reset current kprobe and exit.
+			 *
+			 * pre_handler can hit a breakpoint and can step thru
+			 * before return.
+			 */
+			if (!p->pre_handler || !p->pre_handler(p, regs))
+				setup_singlestep(p, regs, kcb, 0);
+			else
+				reset_current_kprobe();
+		}
+		return true;
+	}
+
+	/*
+	 * The breakpoint instruction was removed right
+	 * after we hit it.  Another cpu has removed
+	 * either a probepoint or a debugger breakpoint
+	 * at this address.  In either case, no further
+	 * handling of this interrupt is appropriate.
+	 * Return back to original instruction, and continue.
+	 */
+	return false;
+}
+
+bool __kprobes
+kprobe_single_step_handler(struct pt_regs *regs)
+{
+	struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
+	unsigned long addr = instruction_pointer(regs);
+	struct kprobe *cur = kprobe_running();
+
+	if (cur && (kcb->kprobe_status & (KPROBE_HIT_SS | KPROBE_REENTER)) &&
+	    ((unsigned long)&cur->ainsn.api.insn[0] + GET_INSN_LENGTH(cur->opcode) == addr)) {
+		kprobes_restore_local_irqflag(kcb, regs);
+		post_kprobe_handler(cur, kcb, regs);
+		return true;
+	}
+	/* not ours, kprobes should ignore it */
+	return false;
+}
+
+/*
+ * Provide a blacklist of symbols identifying ranges which cannot be kprobed.
+ * This blacklist is exposed to userspace via debugfs (kprobes/blacklist).
+ */
+int __init arch_populate_kprobe_blacklist(void)
+{
+	int ret;
+
+	ret = kprobe_add_area_blacklist((unsigned long)__irqentry_text_start,
+					(unsigned long)__irqentry_text_end);
+	return ret;
+}
+
+int __kprobes arch_trampoline_kprobe(struct kprobe *p)
+{
+	return 0;
+}
+
+int __init arch_init_kprobes(void)
+{
+	return 0;
+}
diff --git a/arch/riscv/kernel/probes/rethook.c b/arch/riscv/kernel/probes/rethook.c
new file mode 100644
index 000000000..5c27c1f50
--- /dev/null
+++ b/arch/riscv/kernel/probes/rethook.c
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generic return hook for riscv.
+ */
+
+#include <linux/kprobes.h>
+#include <linux/rethook.h>
+#include "rethook.h"
+
+/* This is called from arch_rethook_trampoline() */
+unsigned long __used arch_rethook_trampoline_callback(struct pt_regs *regs)
+{
+	return rethook_trampoline_handler(regs, regs->s0);
+}
+
+NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);
+
+void arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs *regs, bool mcount)
+{
+	rhn->ret_addr = regs->ra;
+	rhn->frame = regs->s0;
+
+	/* replace return addr with trampoline */
+	regs->ra = (unsigned long)arch_rethook_trampoline;
+}
+
+NOKPROBE_SYMBOL(arch_rethook_prepare);
diff --git a/arch/riscv/kernel/probes/rethook.h b/arch/riscv/kernel/probes/rethook.h
new file mode 100644
index 000000000..4758f7e3c
--- /dev/null
+++ b/arch/riscv/kernel/probes/rethook.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef __RISCV_RETHOOK_H
+#define __RISCV_RETHOOK_H
+
+unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs);
+void arch_rethook_prepare(struct rethook_node *rhn, struct pt_regs *regs, bool mcount);
+
+#endif
diff --git a/arch/riscv/kernel/probes/rethook_trampoline.S b/arch/riscv/kernel/probes/rethook_trampoline.S
new file mode 100644
index 000000000..21bac92a1
--- /dev/null
+++ b/arch/riscv/kernel/probes/rethook_trampoline.S
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Author: Patrick Stählin <me@packi.ch>
+ */
+#include <linux/linkage.h>
+
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+
+	.text
+	.altmacro
+
+	.macro save_all_base_regs
+	REG_S x1,  PT_RA(sp)
+	REG_S x3,  PT_GP(sp)
+	REG_S x4,  PT_TP(sp)
+	REG_S x5,  PT_T0(sp)
+	REG_S x6,  PT_T1(sp)
+	REG_S x7,  PT_T2(sp)
+	REG_S x8,  PT_S0(sp)
+	REG_S x9,  PT_S1(sp)
+	REG_S x10, PT_A0(sp)
+	REG_S x11, PT_A1(sp)
+	REG_S x12, PT_A2(sp)
+	REG_S x13, PT_A3(sp)
+	REG_S x14, PT_A4(sp)
+	REG_S x15, PT_A5(sp)
+	REG_S x16, PT_A6(sp)
+	REG_S x17, PT_A7(sp)
+	REG_S x18, PT_S2(sp)
+	REG_S x19, PT_S3(sp)
+	REG_S x20, PT_S4(sp)
+	REG_S x21, PT_S5(sp)
+	REG_S x22, PT_S6(sp)
+	REG_S x23, PT_S7(sp)
+	REG_S x24, PT_S8(sp)
+	REG_S x25, PT_S9(sp)
+	REG_S x26, PT_S10(sp)
+	REG_S x27, PT_S11(sp)
+	REG_S x28, PT_T3(sp)
+	REG_S x29, PT_T4(sp)
+	REG_S x30, PT_T5(sp)
+	REG_S x31, PT_T6(sp)
+	.endm
+
+	.macro restore_all_base_regs
+	REG_L x3,  PT_GP(sp)
+	REG_L x4,  PT_TP(sp)
+	REG_L x5,  PT_T0(sp)
+	REG_L x6,  PT_T1(sp)
+	REG_L x7,  PT_T2(sp)
+	REG_L x8,  PT_S0(sp)
+	REG_L x9,  PT_S1(sp)
+	REG_L x10, PT_A0(sp)
+	REG_L x11, PT_A1(sp)
+	REG_L x12, PT_A2(sp)
+	REG_L x13, PT_A3(sp)
+	REG_L x14, PT_A4(sp)
+	REG_L x15, PT_A5(sp)
+	REG_L x16, PT_A6(sp)
+	REG_L x17, PT_A7(sp)
+	REG_L x18, PT_S2(sp)
+	REG_L x19, PT_S3(sp)
+	REG_L x20, PT_S4(sp)
+	REG_L x21, PT_S5(sp)
+	REG_L x22, PT_S6(sp)
+	REG_L x23, PT_S7(sp)
+	REG_L x24, PT_S8(sp)
+	REG_L x25, PT_S9(sp)
+	REG_L x26, PT_S10(sp)
+	REG_L x27, PT_S11(sp)
+	REG_L x28, PT_T3(sp)
+	REG_L x29, PT_T4(sp)
+	REG_L x30, PT_T5(sp)
+	REG_L x31, PT_T6(sp)
+	.endm
+
+ENTRY(arch_rethook_trampoline)
+	addi sp, sp, -(PT_SIZE_ON_STACK)
+	save_all_base_regs
+
+	move a0, sp /* pt_regs */
+
+	call arch_rethook_trampoline_callback
+
+	/* use the result as the return-address */
+	move ra, a0
+
+	restore_all_base_regs
+	addi sp, sp, PT_SIZE_ON_STACK
+
+	ret
+ENDPROC(arch_rethook_trampoline)
diff --git a/arch/riscv/kernel/probes/simulate-insn.c b/arch/riscv/kernel/probes/simulate-insn.c
new file mode 100644
index 000000000..a20568bd1
--- /dev/null
+++ b/arch/riscv/kernel/probes/simulate-insn.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/kprobes.h>
+
+#include "decode-insn.h"
+#include "simulate-insn.h"
+
+static inline bool rv_insn_reg_get_val(struct pt_regs *regs, u32 index,
+				       unsigned long *ptr)
+{
+	if (index == 0)
+		*ptr = 0;
+	else if (index <= 31)
+		*ptr = *((unsigned long *)regs + index);
+	else
+		return false;
+
+	return true;
+}
+
+static inline bool rv_insn_reg_set_val(struct pt_regs *regs, u32 index,
+				       unsigned long val)
+{
+	if (index == 0)
+		return false;
+	else if (index <= 31)
+		*((unsigned long *)regs + index) = val;
+	else
+		return false;
+
+	return true;
+}
+
+bool __kprobes simulate_jal(u32 opcode, unsigned long addr, struct pt_regs *regs)
+{
+	/*
+	 *     31    30       21    20     19        12 11 7 6      0
+	 * imm [20] | imm[10:1] | imm[11] | imm[19:12] | rd | opcode
+	 *     1         10          1           8       5    JAL/J
+	 */
+	bool ret;
+	u32 imm;
+	u32 index = (opcode >> 7) & 0x1f;
+
+	ret = rv_insn_reg_set_val(regs, index, addr + 4);
+	if (!ret)
+		return ret;
+
+	imm  = ((opcode >> 21) & 0x3ff) << 1;
+	imm |= ((opcode >> 20) & 0x1)   << 11;
+	imm |= ((opcode >> 12) & 0xff)  << 12;
+	imm |= ((opcode >> 31) & 0x1)   << 20;
+
+	instruction_pointer_set(regs, addr + sign_extend32((imm), 20));
+
+	return ret;
+}
+
+bool __kprobes simulate_jalr(u32 opcode, unsigned long addr, struct pt_regs *regs)
+{
+	/*
+	 * 31          20 19 15 14 12 11 7 6      0
+	 *  offset[11:0] | rs1 | 010 | rd | opcode
+	 *      12         5      3    5    JALR/JR
+	 */
+	bool ret;
+	unsigned long base_addr;
+	u32 imm = (opcode >> 20) & 0xfff;
+	u32 rd_index = (opcode >> 7) & 0x1f;
+	u32 rs1_index = (opcode >> 15) & 0x1f;
+
+	ret = rv_insn_reg_get_val(regs, rs1_index, &base_addr);
+	if (!ret)
+		return ret;
+
+	ret = rv_insn_reg_set_val(regs, rd_index, addr + 4);
+	if (!ret)
+		return ret;
+
+	instruction_pointer_set(regs, (base_addr + sign_extend32((imm), 11))&~1);
+
+	return ret;
+}
+
+#define auipc_rd_idx(opcode) \
+	((opcode >> 7) & 0x1f)
+
+#define auipc_imm(opcode) \
+	((((opcode) >> 12) & 0xfffff) << 12)
+
+#if __riscv_xlen == 64
+#define auipc_offset(opcode)	sign_extend64(auipc_imm(opcode), 31)
+#elif __riscv_xlen == 32
+#define auipc_offset(opcode)	auipc_imm(opcode)
+#else
+#error "Unexpected __riscv_xlen"
+#endif
+
+bool __kprobes simulate_auipc(u32 opcode, unsigned long addr, struct pt_regs *regs)
+{
+	/*
+	 * auipc instruction:
+	 *  31        12 11 7 6      0
+	 * | imm[31:12] | rd | opcode |
+	 *        20       5     7
+	 */
+
+	u32 rd_idx = auipc_rd_idx(opcode);
+	unsigned long rd_val = addr + auipc_offset(opcode);
+
+	if (!rv_insn_reg_set_val(regs, rd_idx, rd_val))
+		return false;
+
+	instruction_pointer_set(regs, addr + 4);
+
+	return true;
+}
+
+#define branch_rs1_idx(opcode) \
+	(((opcode) >> 15) & 0x1f)
+
+#define branch_rs2_idx(opcode) \
+	(((opcode) >> 20) & 0x1f)
+
+#define branch_funct3(opcode) \
+	(((opcode) >> 12) & 0x7)
+
+#define branch_imm(opcode) \
+	(((((opcode) >>  8) & 0xf ) <<  1) | \
+	 ((((opcode) >> 25) & 0x3f) <<  5) | \
+	 ((((opcode) >>  7) & 0x1 ) << 11) | \
+	 ((((opcode) >> 31) & 0x1 ) << 12))
+
+#define branch_offset(opcode) \
+	sign_extend32((branch_imm(opcode)), 12)
+
+#define BRANCH_BEQ	0x0
+#define BRANCH_BNE	0x1
+#define BRANCH_BLT	0x4
+#define BRANCH_BGE	0x5
+#define BRANCH_BLTU	0x6
+#define BRANCH_BGEU	0x7
+
+bool __kprobes simulate_branch(u32 opcode, unsigned long addr, struct pt_regs *regs)
+{
+	/*
+	 * branch instructions:
+	 *      31    30       25 24 20 19 15 14    12 11       8    7      6      0
+	 * | imm[12] | imm[10:5] | rs2 | rs1 | funct3 | imm[4:1] | imm[11] | opcode |
+	 *     1           6        5     5      3         4         1         7
+	 *     imm[12|10:5]        rs2   rs1    000       imm[4:1|11]       1100011  BEQ
+	 *     imm[12|10:5]        rs2   rs1    001       imm[4:1|11]       1100011  BNE
+	 *     imm[12|10:5]        rs2   rs1    100       imm[4:1|11]       1100011  BLT
+	 *     imm[12|10:5]        rs2   rs1    101       imm[4:1|11]       1100011  BGE
+	 *     imm[12|10:5]        rs2   rs1    110       imm[4:1|11]       1100011  BLTU
+	 *     imm[12|10:5]        rs2   rs1    111       imm[4:1|11]       1100011  BGEU
+	 */
+
+	s32 offset;
+	s32 offset_tmp;
+	unsigned long rs1_val;
+	unsigned long rs2_val;
+
+	if (!rv_insn_reg_get_val(regs, branch_rs1_idx(opcode), &rs1_val) ||
+	    !rv_insn_reg_get_val(regs, branch_rs2_idx(opcode), &rs2_val))
+		return false;
+
+	offset_tmp = branch_offset(opcode);
+	switch (branch_funct3(opcode)) {
+	case BRANCH_BEQ:
+		offset = (rs1_val == rs2_val) ? offset_tmp : 4;
+		break;
+	case BRANCH_BNE:
+		offset = (rs1_val != rs2_val) ? offset_tmp : 4;
+		break;
+	case BRANCH_BLT:
+		offset = ((long)rs1_val < (long)rs2_val) ? offset_tmp : 4;
+		break;
+	case BRANCH_BGE:
+		offset = ((long)rs1_val >= (long)rs2_val) ? offset_tmp : 4;
+		break;
+	case BRANCH_BLTU:
+		offset = (rs1_val < rs2_val) ? offset_tmp : 4;
+		break;
+	case BRANCH_BGEU:
+		offset = (rs1_val >= rs2_val) ? offset_tmp : 4;
+		break;
+	default:
+		return false;
+	}
+
+	instruction_pointer_set(regs, addr + offset);
+
+	return true;
+}
diff --git a/arch/riscv/kernel/probes/simulate-insn.h b/arch/riscv/kernel/probes/simulate-insn.h
new file mode 100644
index 000000000..de8474146
--- /dev/null
+++ b/arch/riscv/kernel/probes/simulate-insn.h
@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _RISCV_KERNEL_PROBES_SIMULATE_INSN_H
+#define _RISCV_KERNEL_PROBES_SIMULATE_INSN_H
+
+#define __RISCV_INSN_FUNCS(name, mask, val)				\
+static __always_inline bool riscv_insn_is_##name(probe_opcode_t code)	\
+{									\
+	BUILD_BUG_ON(~(mask) & (val));					\
+	return (code & (mask)) == (val);				\
+}									\
+bool simulate_##name(u32 opcode, unsigned long addr,			\
+		     struct pt_regs *regs)
+
+#define RISCV_INSN_REJECTED(name, code)					\
+	do {								\
+		if (riscv_insn_is_##name(code)) {			\
+			return INSN_REJECTED;				\
+		}							\
+	} while (0)
+
+__RISCV_INSN_FUNCS(system,	0x7f, 0x73);
+__RISCV_INSN_FUNCS(fence,	0x7f, 0x0f);
+
+#define RISCV_INSN_SET_SIMULATE(name, code)				\
+	do {								\
+		if (riscv_insn_is_##name(code)) {			\
+			api->handler = simulate_##name;			\
+			return INSN_GOOD_NO_SLOT;			\
+		}							\
+	} while (0)
+
+__RISCV_INSN_FUNCS(c_j,		0xe003, 0xa001);
+__RISCV_INSN_FUNCS(c_jr,	0xf07f, 0x8002);
+__RISCV_INSN_FUNCS(c_jal,	0xe003, 0x2001);
+__RISCV_INSN_FUNCS(c_jalr,	0xf07f, 0x9002);
+__RISCV_INSN_FUNCS(c_beqz,	0xe003, 0xc001);
+__RISCV_INSN_FUNCS(c_bnez,	0xe003, 0xe001);
+__RISCV_INSN_FUNCS(c_ebreak,	0xffff, 0x9002);
+
+__RISCV_INSN_FUNCS(auipc,	0x7f, 0x17);
+__RISCV_INSN_FUNCS(branch,	0x7f, 0x63);
+
+__RISCV_INSN_FUNCS(jal,		0x7f, 0x6f);
+__RISCV_INSN_FUNCS(jalr,	0x707f, 0x67);
+
+#endif /* _RISCV_KERNEL_PROBES_SIMULATE_INSN_H */
diff --git a/arch/riscv/kernel/probes/uprobes.c b/arch/riscv/kernel/probes/uprobes.c
new file mode 100644
index 000000000..c976a21cd
--- /dev/null
+++ b/arch/riscv/kernel/probes/uprobes.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/highmem.h>
+#include <linux/ptrace.h>
+#include <linux/uprobes.h>
+
+#include "decode-insn.h"
+
+#define UPROBE_TRAP_NR	UINT_MAX
+
+bool is_swbp_insn(uprobe_opcode_t *insn)
+{
+#ifdef CONFIG_RISCV_ISA_C
+	return (*insn & 0xffff) == UPROBE_SWBP_INSN;
+#else
+	return *insn == UPROBE_SWBP_INSN;
+#endif
+}
+
+unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
+{
+	return instruction_pointer(regs);
+}
+
+int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm,
+			     unsigned long addr)
+{
+	probe_opcode_t opcode;
+
+	opcode = *(probe_opcode_t *)(&auprobe->insn[0]);
+
+	auprobe->insn_size = GET_INSN_LENGTH(opcode);
+
+	switch (riscv_probe_decode_insn(&opcode, &auprobe->api)) {
+	case INSN_REJECTED:
+		return -EINVAL;
+
+	case INSN_GOOD_NO_SLOT:
+		auprobe->simulate = true;
+		break;
+
+	case INSN_GOOD:
+		auprobe->simulate = false;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
+{
+	struct uprobe_task *utask = current->utask;
+
+	utask->autask.saved_cause = current->thread.bad_cause;
+	current->thread.bad_cause = UPROBE_TRAP_NR;
+
+	instruction_pointer_set(regs, utask->xol_vaddr);
+
+	return 0;
+}
+
+int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
+{
+	struct uprobe_task *utask = current->utask;
+
+	WARN_ON_ONCE(current->thread.bad_cause != UPROBE_TRAP_NR);
+
+	instruction_pointer_set(regs, utask->vaddr + auprobe->insn_size);
+
+	return 0;
+}
+
+bool arch_uprobe_xol_was_trapped(struct task_struct *t)
+{
+	if (t->thread.bad_cause != UPROBE_TRAP_NR)
+		return true;
+
+	return false;
+}
+
+bool arch_uprobe_skip_sstep(struct arch_uprobe *auprobe, struct pt_regs *regs)
+{
+	probe_opcode_t insn;
+	unsigned long addr;
+
+	if (!auprobe->simulate)
+		return false;
+
+	insn = *(probe_opcode_t *)(&auprobe->insn[0]);
+	addr = instruction_pointer(regs);
+
+	if (auprobe->api.handler)
+		auprobe->api.handler(insn, addr, regs);
+
+	return true;
+}
+
+void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs)
+{
+	struct uprobe_task *utask = current->utask;
+
+	/*
+	 * Task has received a fatal signal, so reset back to probbed
+	 * address.
+	 */
+	instruction_pointer_set(regs, utask->vaddr);
+}
+
+bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,
+		struct pt_regs *regs)
+{
+	if (ctx == RP_CHECK_CHAIN_CALL)
+		return regs->sp <= ret->stack;
+	else
+		return regs->sp < ret->stack;
+}
+
+unsigned long
+arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr,
+				  struct pt_regs *regs)
+{
+	unsigned long ra;
+
+	ra = regs->ra;
+
+	regs->ra = trampoline_vaddr;
+
+	return ra;
+}
+
+int arch_uprobe_exception_notify(struct notifier_block *self,
+				 unsigned long val, void *data)
+{
+	return NOTIFY_DONE;
+}
+
+bool uprobe_breakpoint_handler(struct pt_regs *regs)
+{
+	if (uprobe_pre_sstep_notifier(regs))
+		return true;
+
+	return false;
+}
+
+bool uprobe_single_step_handler(struct pt_regs *regs)
+{
+	if (uprobe_post_sstep_notifier(regs))
+		return true;
+
+	return false;
+}
+
+void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
+			   void *src, unsigned long len)
+{
+	/* Initialize the slot */
+	void *kaddr = kmap_atomic(page);
+	void *dst = kaddr + (vaddr & ~PAGE_MASK);
+
+	memcpy(dst, src, len);
+
+	/* Add ebreak behind opcode to simulate singlestep */
+	if (vaddr) {
+		dst += GET_INSN_LENGTH(*(probe_opcode_t *)src);
+		*(uprobe_opcode_t *)dst = __BUG_INSN_32;
+	}
+
+	kunmap_atomic(kaddr);
+
+	/*
+	 * We probably need flush_icache_user_page() but it needs vma.
+	 * This should work on most of architectures by default. If
+	 * architecture needs to do something different it can define
+	 * its own version of the function.
+	 */
+	flush_dcache_page(page);
+}