Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 416 insertions, 19 deletions

diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index f2417ac54edd..f5a668736c79 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -8,6 +8,8 @@
 #include <linux/bitfield.h>
 #include <linux/bpf.h>
 #include <linux/filter.h>
+#include <linux/memory.h>
+#include <linux/stop_machine.h>
 #include "bpf_jit.h"
 
 #define RV_REG_TCC RV_REG_A6
@@ -238,7 +240,7 @@ static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx)
 	if (!is_tail_call)
 		emit_mv(RV_REG_A0, RV_REG_A5, ctx);
 	emit_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA,
-		  is_tail_call ? 4 : 0, /* skip TCC init */
+		  is_tail_call ? 20 : 0, /* skip reserved nops and TCC init */
 		  ctx);
 }
 
@@ -428,12 +430,12 @@ static void emit_sext_32_rd(u8 *rd, struct rv_jit_context *ctx)
 	*rd = RV_REG_T2;
 }
 
-static int emit_jump_and_link(u8 rd, s64 rvoff, bool force_jalr,
+static int emit_jump_and_link(u8 rd, s64 rvoff, bool fixed_addr,
 			      struct rv_jit_context *ctx)
 {
 	s64 upper, lower;
 
-	if (rvoff && is_21b_int(rvoff) && !force_jalr) {
+	if (rvoff && fixed_addr && is_21b_int(rvoff)) {
 		emit(rv_jal(rd, rvoff >> 1), ctx);
 		return 0;
 	} else if (in_auipc_jalr_range(rvoff)) {
@@ -454,24 +456,17 @@ static bool is_signed_bpf_cond(u8 cond)
 		cond == BPF_JSGE || cond == BPF_JSLE;
 }
 
-static int emit_call(bool fixed, u64 addr, struct rv_jit_context *ctx)
+static int emit_call(u64 addr, bool fixed_addr, struct rv_jit_context *ctx)
 {
 	s64 off = 0;
 	u64 ip;
-	u8 rd;
-	int ret;
 
 	if (addr && ctx->insns) {
 		ip = (u64)(long)(ctx->insns + ctx->ninsns);
 		off = addr - ip;
 	}
 
-	ret = emit_jump_and_link(RV_REG_RA, off, !fixed, ctx);
-	if (ret)
-		return ret;
-	rd = bpf_to_rv_reg(BPF_REG_0, ctx);
-	emit_mv(rd, RV_REG_A0, ctx);
-	return 0;
+	return emit_jump_and_link(RV_REG_RA, off, fixed_addr, ctx);
 }
 
 static void emit_atomic(u8 rd, u8 rs, s16 off, s32 imm, bool is64,
@@ -622,6 +617,401 @@ static int add_exception_handler(const struct bpf_insn *insn,
 	return 0;
 }
 
+static int gen_call_or_nops(void *target, void *ip, u32 *insns)
+{
+	s64 rvoff;
+	int i, ret;
+	struct rv_jit_context ctx;
+
+	ctx.ninsns = 0;
+	ctx.insns = (u16 *)insns;
+
+	if (!target) {
+		for (i = 0; i < 4; i++)
+			emit(rv_nop(), &ctx);
+		return 0;
+	}
+
+	rvoff = (s64)(target - (ip + 4));
+	emit(rv_sd(RV_REG_SP, -8, RV_REG_RA), &ctx);
+	ret = emit_jump_and_link(RV_REG_RA, rvoff, false, &ctx);
+	if (ret)
+		return ret;
+	emit(rv_ld(RV_REG_RA, -8, RV_REG_SP), &ctx);
+
+	return 0;
+}
+
+static int gen_jump_or_nops(void *target, void *ip, u32 *insns)
+{
+	s64 rvoff;
+	struct rv_jit_context ctx;
+
+	ctx.ninsns = 0;
+	ctx.insns = (u16 *)insns;
+
+	if (!target) {
+		emit(rv_nop(), &ctx);
+		emit(rv_nop(), &ctx);
+		return 0;
+	}
+
+	rvoff = (s64)(target - ip);
+	return emit_jump_and_link(RV_REG_ZERO, rvoff, false, &ctx);
+}
+
+int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type poke_type,
+		       void *old_addr, void *new_addr)
+{
+	u32 old_insns[4], new_insns[4];
+	bool is_call = poke_type == BPF_MOD_CALL;
+	int (*gen_insns)(void *target, void *ip, u32 *insns);
+	int ninsns = is_call ? 4 : 2;
+	int ret;
+
+	if (!is_bpf_text_address((unsigned long)ip))
+		return -ENOTSUPP;
+
+	gen_insns = is_call ? gen_call_or_nops : gen_jump_or_nops;
+
+	ret = gen_insns(old_addr, ip, old_insns);
+	if (ret)
+		return ret;
+
+	if (memcmp(ip, old_insns, ninsns * 4))
+		return -EFAULT;
+
+	ret = gen_insns(new_addr, ip, new_insns);
+	if (ret)
+		return ret;
+
+	cpus_read_lock();
+	mutex_lock(&text_mutex);
+	if (memcmp(ip, new_insns, ninsns * 4))
+		ret = patch_text(ip, new_insns, ninsns);
+	mutex_unlock(&text_mutex);
+	cpus_read_unlock();
+
+	return ret;
+}
+
+static void store_args(int nregs, int args_off, struct rv_jit_context *ctx)
+{
+	int i;
+
+	for (i = 0; i < nregs; i++) {
+		emit_sd(RV_REG_FP, -args_off, RV_REG_A0 + i, ctx);
+		args_off -= 8;
+	}
+}
+
+static void restore_args(int nregs, int args_off, struct rv_jit_context *ctx)
+{
+	int i;
+
+	for (i = 0; i < nregs; i++) {
+		emit_ld(RV_REG_A0 + i, -args_off, RV_REG_FP, ctx);
+		args_off -= 8;
+	}
+}
+
+static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_off,
+			   int run_ctx_off, bool save_ret, struct rv_jit_context *ctx)
+{
+	int ret, branch_off;
+	struct bpf_prog *p = l->link.prog;
+	int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
+
+	if (l->cookie) {
+		emit_imm(RV_REG_T1, l->cookie, ctx);
+		emit_sd(RV_REG_FP, -run_ctx_off + cookie_off, RV_REG_T1, ctx);
+	} else {
+		emit_sd(RV_REG_FP, -run_ctx_off + cookie_off, RV_REG_ZERO, ctx);
+	}
+
+	/* arg1: prog */
+	emit_imm(RV_REG_A0, (const s64)p, ctx);
+	/* arg2: &run_ctx */
+	emit_addi(RV_REG_A1, RV_REG_FP, -run_ctx_off, ctx);
+	ret = emit_call((const u64)bpf_trampoline_enter(p), true, ctx);
+	if (ret)
+		return ret;
+
+	/* if (__bpf_prog_enter(prog) == 0)
+	 *	goto skip_exec_of_prog;
+	 */
+	branch_off = ctx->ninsns;
+	/* nop reserved for conditional jump */
+	emit(rv_nop(), ctx);
+
+	/* store prog start time */
+	emit_mv(RV_REG_S1, RV_REG_A0, ctx);
+
+	/* arg1: &args_off */
+	emit_addi(RV_REG_A0, RV_REG_FP, -args_off, ctx);
+	if (!p->jited)
+		/* arg2: progs[i]->insnsi for interpreter */
+		emit_imm(RV_REG_A1, (const s64)p->insnsi, ctx);
+	ret = emit_call((const u64)p->bpf_func, true, ctx);
+	if (ret)
+		return ret;
+
+	if (save_ret)
+		emit_sd(RV_REG_FP, -retval_off, regmap[BPF_REG_0], ctx);
+
+	/* update branch with beqz */
+	if (ctx->insns) {
+		int offset = ninsns_rvoff(ctx->ninsns - branch_off);
+		u32 insn = rv_beq(RV_REG_A0, RV_REG_ZERO, offset >> 1);
+		*(u32 *)(ctx->insns + branch_off) = insn;
+	}
+
+	/* arg1: prog */
+	emit_imm(RV_REG_A0, (const s64)p, ctx);
+	/* arg2: prog start time */
+	emit_mv(RV_REG_A1, RV_REG_S1, ctx);
+	/* arg3: &run_ctx */
+	emit_addi(RV_REG_A2, RV_REG_FP, -run_ctx_off, ctx);
+	ret = emit_call((const u64)bpf_trampoline_exit(p), true, ctx);
+
+	return ret;
+}
+
+static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
+					 const struct btf_func_model *m,
+					 struct bpf_tramp_links *tlinks,
+					 void *func_addr, u32 flags,
+					 struct rv_jit_context *ctx)
+{
+	int i, ret, offset;
+	int *branches_off = NULL;
+	int stack_size = 0, nregs = m->nr_args;
+	int retaddr_off, fp_off, retval_off, args_off;
+	int nregs_off, ip_off, run_ctx_off, sreg_off;
+	struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
+	struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
+	struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+	void *orig_call = func_addr;
+	bool save_ret;
+	u32 insn;
+
+	/* Generated trampoline stack layout:
+	 *
+	 * FP - 8	    [ RA of parent func	] return address of parent
+	 *					  function
+	 * FP - retaddr_off [ RA of traced func	] return address of traced
+	 *					  function
+	 * FP - fp_off	    [ FP of parent func ]
+	 *
+	 * FP - retval_off  [ return value      ] BPF_TRAMP_F_CALL_ORIG or
+	 *					  BPF_TRAMP_F_RET_FENTRY_RET
+	 *                  [ argN              ]
+	 *                  [ ...               ]
+	 * FP - args_off    [ arg1              ]
+	 *
+	 * FP - nregs_off   [ regs count        ]
+	 *
+	 * FP - ip_off      [ traced func	] BPF_TRAMP_F_IP_ARG
+	 *
+	 * FP - run_ctx_off [ bpf_tramp_run_ctx ]
+	 *
+	 * FP - sreg_off    [ callee saved reg	]
+	 *
+	 *		    [ pads              ] pads for 16 bytes alignment
+	 */
+
+	if (flags & (BPF_TRAMP_F_ORIG_STACK | BPF_TRAMP_F_SHARE_IPMODIFY))
+		return -ENOTSUPP;
+
+	/* extra regiters for struct arguments */
+	for (i = 0; i < m->nr_args; i++)
+		if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
+			nregs += round_up(m->arg_size[i], 8) / 8 - 1;
+
+	/* 8 arguments passed by registers */
+	if (nregs > 8)
+		return -ENOTSUPP;
+
+	/* room for parent function return address */
+	stack_size += 8;
+
+	stack_size += 8;
+	retaddr_off = stack_size;
+
+	stack_size += 8;
+	fp_off = stack_size;
+
+	save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET);
+	if (save_ret) {
+		stack_size += 8;
+		retval_off = stack_size;
+	}
+
+	stack_size += nregs * 8;
+	args_off = stack_size;
+
+	stack_size += 8;
+	nregs_off = stack_size;
+
+	if (flags & BPF_TRAMP_F_IP_ARG) {
+		stack_size += 8;
+		ip_off = stack_size;
+	}
+
+	stack_size += round_up(sizeof(struct bpf_tramp_run_ctx), 8);
+	run_ctx_off = stack_size;
+
+	stack_size += 8;
+	sreg_off = stack_size;
+
+	stack_size = round_up(stack_size, 16);
+
+	emit_addi(RV_REG_SP, RV_REG_SP, -stack_size, ctx);
+
+	emit_sd(RV_REG_SP, stack_size - retaddr_off, RV_REG_RA, ctx);
+	emit_sd(RV_REG_SP, stack_size - fp_off, RV_REG_FP, ctx);
+
+	emit_addi(RV_REG_FP, RV_REG_SP, stack_size, ctx);
+
+	/* callee saved register S1 to pass start time */
+	emit_sd(RV_REG_FP, -sreg_off, RV_REG_S1, ctx);
+
+	/* store ip address of the traced function */
+	if (flags & BPF_TRAMP_F_IP_ARG) {
+		emit_imm(RV_REG_T1, (const s64)func_addr, ctx);
+		emit_sd(RV_REG_FP, -ip_off, RV_REG_T1, ctx);
+	}
+
+	emit_li(RV_REG_T1, nregs, ctx);
+	emit_sd(RV_REG_FP, -nregs_off, RV_REG_T1, ctx);
+
+	store_args(nregs, args_off, ctx);
+
+	/* skip to actual body of traced function */
+	if (flags & BPF_TRAMP_F_SKIP_FRAME)
+		orig_call += 16;
+
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		emit_imm(RV_REG_A0, (const s64)im, ctx);
+		ret = emit_call((const u64)__bpf_tramp_enter, true, ctx);
+		if (ret)
+			return ret;
+	}
+
+	for (i = 0; i < fentry->nr_links; i++) {
+		ret = invoke_bpf_prog(fentry->links[i], args_off, retval_off, run_ctx_off,
+				      flags & BPF_TRAMP_F_RET_FENTRY_RET, ctx);
+		if (ret)
+			return ret;
+	}
+
+	if (fmod_ret->nr_links) {
+		branches_off = kcalloc(fmod_ret->nr_links, sizeof(int), GFP_KERNEL);
+		if (!branches_off)
+			return -ENOMEM;
+
+		/* cleanup to avoid garbage return value confusion */
+		emit_sd(RV_REG_FP, -retval_off, RV_REG_ZERO, ctx);
+		for (i = 0; i < fmod_ret->nr_links; i++) {
+			ret = invoke_bpf_prog(fmod_ret->links[i], args_off, retval_off,
+					      run_ctx_off, true, ctx);
+			if (ret)
+				goto out;
+			emit_ld(RV_REG_T1, -retval_off, RV_REG_FP, ctx);
+			branches_off[i] = ctx->ninsns;
+			/* nop reserved for conditional jump */
+			emit(rv_nop(), ctx);
+		}
+	}
+
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		restore_args(nregs, args_off, ctx);
+		ret = emit_call((const u64)orig_call, true, ctx);
+		if (ret)
+			goto out;
+		emit_sd(RV_REG_FP, -retval_off, RV_REG_A0, ctx);
+		im->ip_after_call = ctx->insns + ctx->ninsns;
+		/* 2 nops reserved for auipc+jalr pair */
+		emit(rv_nop(), ctx);
+		emit(rv_nop(), ctx);
+	}
+
+	/* update branches saved in invoke_bpf_mod_ret with bnez */
+	for (i = 0; ctx->insns && i < fmod_ret->nr_links; i++) {
+		offset = ninsns_rvoff(ctx->ninsns - branches_off[i]);
+		insn = rv_bne(RV_REG_T1, RV_REG_ZERO, offset >> 1);
+		*(u32 *)(ctx->insns + branches_off[i]) = insn;
+	}
+
+	for (i = 0; i < fexit->nr_links; i++) {
+		ret = invoke_bpf_prog(fexit->links[i], args_off, retval_off,
+				      run_ctx_off, false, ctx);
+		if (ret)
+			goto out;
+	}
+
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		im->ip_epilogue = ctx->insns + ctx->ninsns;
+		emit_imm(RV_REG_A0, (const s64)im, ctx);
+		ret = emit_call((const u64)__bpf_tramp_exit, true, ctx);
+		if (ret)
+			goto out;
+	}
+
+	if (flags & BPF_TRAMP_F_RESTORE_REGS)
+		restore_args(nregs, args_off, ctx);
+
+	if (save_ret)
+		emit_ld(RV_REG_A0, -retval_off, RV_REG_FP, ctx);
+
+	emit_ld(RV_REG_S1, -sreg_off, RV_REG_FP, ctx);
+
+	if (flags & BPF_TRAMP_F_SKIP_FRAME)
+		/* return address of parent function */
+		emit_ld(RV_REG_RA, stack_size - 8, RV_REG_SP, ctx);
+	else
+		/* return address of traced function */
+		emit_ld(RV_REG_RA, stack_size - retaddr_off, RV_REG_SP, ctx);
+
+	emit_ld(RV_REG_FP, stack_size - fp_off, RV_REG_SP, ctx);
+	emit_addi(RV_REG_SP, RV_REG_SP, stack_size, ctx);
+
+	emit_jalr(RV_REG_ZERO, RV_REG_RA, 0, ctx);
+
+	ret = ctx->ninsns;
+out:
+	kfree(branches_off);
+	return ret;
+}
+
+int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image,
+				void *image_end, const struct btf_func_model *m,
+				u32 flags, struct bpf_tramp_links *tlinks,
+				void *func_addr)
+{
+	int ret;
+	struct rv_jit_context ctx;
+
+	ctx.ninsns = 0;
+	ctx.insns = NULL;
+	ret = __arch_prepare_bpf_trampoline(im, m, tlinks, func_addr, flags, &ctx);
+	if (ret < 0)
+		return ret;
+
+	if (ninsns_rvoff(ret) > (long)image_end - (long)image)
+		return -EFBIG;
+
+	ctx.ninsns = 0;
+	ctx.insns = image;
+	ret = __arch_prepare_bpf_trampoline(im, m, tlinks, func_addr, flags, &ctx);
+	if (ret < 0)
+		return ret;
+
+	bpf_flush_icache(ctx.insns, ctx.insns + ctx.ninsns);
+
+	return ninsns_rvoff(ret);
+}
+
 int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 		      bool extra_pass)
 {
@@ -913,7 +1303,7 @@ out_be:
 	/* JUMP off */
 	case BPF_JMP | BPF_JA:
 		rvoff = rv_offset(i, off, ctx);
-		ret = emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx);
+		ret = emit_jump_and_link(RV_REG_ZERO, rvoff, true, ctx);
 		if (ret)
 			return ret;
 		break;
@@ -1032,17 +1422,20 @@ out_be:
 	/* function call */
 	case BPF_JMP | BPF_CALL:
 	{
-		bool fixed;
+		bool fixed_addr;
 		u64 addr;
 
 		mark_call(ctx);
-		ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass, &addr,
-					    &fixed);
+		ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass,
+					    &addr, &fixed_addr);
 		if (ret < 0)
 			return ret;
-		ret = emit_call(fixed, addr, ctx);
+
+		ret = emit_call(addr, fixed_addr, ctx);
 		if (ret)
 			return ret;
+
+		emit_mv(bpf_to_rv_reg(BPF_REG_0, ctx), RV_REG_A0, ctx);
 		break;
 	}
 	/* tail call */
@@ -1057,7 +1450,7 @@ out_be:
 			break;
 
 		rvoff = epilogue_offset(ctx);
-		ret = emit_jump_and_link(RV_REG_ZERO, rvoff, false, ctx);
+		ret = emit_jump_and_link(RV_REG_ZERO, rvoff, true, ctx);
 		if (ret)
 			return ret;
 		break;
@@ -1270,7 +1663,7 @@ out_be:
 
 void bpf_jit_build_prologue(struct rv_jit_context *ctx)
 {
-	int stack_adjust = 0, store_offset, bpf_stack_adjust;
+	int i, stack_adjust = 0, store_offset, bpf_stack_adjust;
 
 	bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16);
 	if (bpf_stack_adjust)
@@ -1297,6 +1690,10 @@ void bpf_jit_build_prologue(struct rv_jit_context *ctx)
 
 	store_offset = stack_adjust - 8;
 
+	/* reserve 4 nop insns */
+	for (i = 0; i < 4; i++)
+		emit(rv_nop(), ctx);
+
 	/* First instruction is always setting the tail-call-counter
 	 * (TCC) register. This instruction is skipped for tail calls.
 	 * Force using a 4-byte (non-compressed) instruction.