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().
  ...

1 files changed, 489 insertions, 0 deletions

diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c
new file mode 100644
index 000000000..42acc3b52
--- /dev/null
+++ b/arch/parisc/kernel/unwind.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kernel unwinding support
+ *
+ * (c) 2002-2004 Randolph Chung <tausq@debian.org>
+ *
+ * Derived partially from the IA64 implementation. The PA-RISC
+ * Runtime Architecture Document is also a useful reference to
+ * understand what is happening here
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/sort.h>
+#include <linux/sched/task_stack.h>
+
+#include <linux/uaccess.h>
+#include <asm/assembly.h>
+#include <asm/asm-offsets.h>
+#include <asm/ptrace.h>
+
+#include <asm/unwind.h>
+#include <asm/switch_to.h>
+#include <asm/sections.h>
+
+/* #define DEBUG 1 */
+#ifdef DEBUG
+#define dbg(x...) pr_debug(x)
+#else
+#define dbg(x...)
+#endif
+
+#define KERNEL_START (KERNEL_BINARY_TEXT_START)
+
+extern struct unwind_table_entry __start___unwind[];
+extern struct unwind_table_entry __stop___unwind[];
+
+static DEFINE_SPINLOCK(unwind_lock);
+/*
+ * the kernel unwind block is not dynamically allocated so that
+ * we can call unwind_init as early in the bootup process as 
+ * possible (before the slab allocator is initialized)
+ */
+static struct unwind_table kernel_unwind_table __ro_after_init;
+static LIST_HEAD(unwind_tables);
+
+static inline const struct unwind_table_entry *
+find_unwind_entry_in_table(const struct unwind_table *table, unsigned long addr)
+{
+	const struct unwind_table_entry *e = NULL;
+	unsigned long lo, hi, mid;
+
+	lo = 0; 
+	hi = table->length - 1; 
+	
+	while (lo <= hi) {
+		mid = (hi - lo) / 2 + lo;
+		e = &table->table[mid];
+		if (addr < e->region_start)
+			hi = mid - 1;
+		else if (addr > e->region_end)
+			lo = mid + 1;
+		else
+			return e;
+	}
+
+	return NULL;
+}
+
+static const struct unwind_table_entry *
+find_unwind_entry(unsigned long addr)
+{
+	struct unwind_table *table;
+	const struct unwind_table_entry *e = NULL;
+
+	if (addr >= kernel_unwind_table.start && 
+	    addr <= kernel_unwind_table.end)
+		e = find_unwind_entry_in_table(&kernel_unwind_table, addr);
+	else {
+		unsigned long flags;
+
+		spin_lock_irqsave(&unwind_lock, flags);
+		list_for_each_entry(table, &unwind_tables, list) {
+			if (addr >= table->start && 
+			    addr <= table->end)
+				e = find_unwind_entry_in_table(table, addr);
+			if (e) {
+				/* Move-to-front to exploit common traces */
+				list_move(&table->list, &unwind_tables);
+				break;
+			}
+		}
+		spin_unlock_irqrestore(&unwind_lock, flags);
+	}
+
+	return e;
+}
+
+static void
+unwind_table_init(struct unwind_table *table, const char *name,
+		  unsigned long base_addr, unsigned long gp,
+		  void *table_start, void *table_end)
+{
+	struct unwind_table_entry *start = table_start;
+	struct unwind_table_entry *end = 
+		(struct unwind_table_entry *)table_end - 1;
+
+	table->name = name;
+	table->base_addr = base_addr;
+	table->gp = gp;
+	table->start = base_addr + start->region_start;
+	table->end = base_addr + end->region_end;
+	table->table = (struct unwind_table_entry *)table_start;
+	table->length = end - start + 1;
+	INIT_LIST_HEAD(&table->list);
+
+	for (; start <= end; start++) {
+		if (start < end && 
+		    start->region_end > (start+1)->region_start) {
+			pr_warn("Out of order unwind entry! %px and %px\n",
+				start, start+1);
+		}
+
+		start->region_start += base_addr;
+		start->region_end += base_addr;
+	}
+}
+
+static int cmp_unwind_table_entry(const void *a, const void *b)
+{
+	return ((const struct unwind_table_entry *)a)->region_start
+	     - ((const struct unwind_table_entry *)b)->region_start;
+}
+
+static void
+unwind_table_sort(struct unwind_table_entry *start,
+		  struct unwind_table_entry *finish)
+{
+	sort(start, finish - start, sizeof(struct unwind_table_entry),
+	     cmp_unwind_table_entry, NULL);
+}
+
+struct unwind_table *
+unwind_table_add(const char *name, unsigned long base_addr, 
+		 unsigned long gp,
+                 void *start, void *end)
+{
+	struct unwind_table *table;
+	unsigned long flags;
+	struct unwind_table_entry *s = (struct unwind_table_entry *)start;
+	struct unwind_table_entry *e = (struct unwind_table_entry *)end;
+
+	unwind_table_sort(s, e);
+
+	table = kmalloc(sizeof(struct unwind_table), GFP_USER);
+	if (table == NULL)
+		return NULL;
+	unwind_table_init(table, name, base_addr, gp, start, end);
+	spin_lock_irqsave(&unwind_lock, flags);
+	list_add_tail(&table->list, &unwind_tables);
+	spin_unlock_irqrestore(&unwind_lock, flags);
+
+	return table;
+}
+
+void unwind_table_remove(struct unwind_table *table)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&unwind_lock, flags);
+	list_del(&table->list);
+	spin_unlock_irqrestore(&unwind_lock, flags);
+
+	kfree(table);
+}
+
+/* Called from setup_arch to import the kernel unwind info */
+int __init unwind_init(void)
+{
+	long start, stop;
+	register unsigned long gp __asm__ ("r27");
+
+	start = (long)&__start___unwind[0];
+	stop = (long)&__stop___unwind[0];
+
+	dbg("unwind_init: start = 0x%lx, end = 0x%lx, entries = %lu\n",
+	    start, stop,
+	    (stop - start) / sizeof(struct unwind_table_entry));
+
+	unwind_table_init(&kernel_unwind_table, "kernel", KERNEL_START,
+			  gp, 
+			  &__start___unwind[0], &__stop___unwind[0]);
+#if 0
+	{
+		int i;
+		for (i = 0; i < 10; i++)
+		{
+			printk("region 0x%x-0x%x\n", 
+				__start___unwind[i].region_start, 
+				__start___unwind[i].region_end);
+		}
+	}
+#endif
+	return 0;
+}
+
+static bool pc_is_kernel_fn(unsigned long pc, void *fn)
+{
+	return (unsigned long)dereference_kernel_function_descriptor(fn) == pc;
+}
+
+static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int frame_size)
+{
+	/*
+	 * We have to use void * instead of a function pointer, because
+	 * function pointers aren't a pointer to the function on 64-bit.
+	 * Make them const so the compiler knows they live in .text
+	 * Note: We could use dereference_kernel_function_descriptor()
+	 * instead but we want to keep it simple here.
+	 */
+	extern void * const handle_interruption;
+	extern void * const ret_from_kernel_thread;
+	extern void * const syscall_exit;
+	extern void * const intr_return;
+	extern void * const _switch_to_ret;
+#ifdef CONFIG_IRQSTACKS
+	extern void * const _call_on_stack;
+#endif /* CONFIG_IRQSTACKS */
+
+	if (pc_is_kernel_fn(pc, handle_interruption)) {
+		struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN);
+		dbg("Unwinding through handle_interruption()\n");
+		info->prev_sp = regs->gr[30];
+		info->prev_ip = regs->iaoq[0];
+		return 1;
+	}
+
+	if (pc_is_kernel_fn(pc, ret_from_kernel_thread) ||
+	    pc_is_kernel_fn(pc, syscall_exit)) {
+		info->prev_sp = info->prev_ip = 0;
+		return 1;
+	}
+
+	if (pc_is_kernel_fn(pc, intr_return)) {
+		struct pt_regs *regs;
+
+		dbg("Found intr_return()\n");
+		regs = (struct pt_regs *)(info->sp - PT_SZ_ALGN);
+		info->prev_sp = regs->gr[30];
+		info->prev_ip = regs->iaoq[0];
+		info->rp = regs->gr[2];
+		return 1;
+	}
+
+	if (pc_is_kernel_fn(pc, _switch_to) ||
+	    pc_is_kernel_fn(pc, _switch_to_ret)) {
+		info->prev_sp = info->sp - CALLEE_SAVE_FRAME_SIZE;
+		info->prev_ip = *(unsigned long *)(info->prev_sp - RP_OFFSET);
+		return 1;
+	}
+
+#ifdef CONFIG_IRQSTACKS
+	if (pc_is_kernel_fn(pc, _call_on_stack)) {
+		info->prev_sp = *(unsigned long *)(info->sp - FRAME_SIZE - REG_SZ);
+		info->prev_ip = *(unsigned long *)(info->sp - FRAME_SIZE - RP_OFFSET);
+		return 1;
+	}
+#endif
+	return 0;
+}
+
+static void unwind_frame_regs(struct unwind_frame_info *info)
+{
+	const struct unwind_table_entry *e;
+	unsigned long npc;
+	unsigned int insn;
+	long frame_size = 0;
+	int looking_for_rp, rpoffset = 0;
+
+	e = find_unwind_entry(info->ip);
+	if (e == NULL) {
+		unsigned long sp;
+
+		dbg("Cannot find unwind entry for %pS; forced unwinding\n",
+			(void *) info->ip);
+
+		/* Since we are doing the unwinding blind, we don't know if
+		   we are adjusting the stack correctly or extracting the rp
+		   correctly. The rp is checked to see if it belongs to the
+		   kernel text section, if not we assume we don't have a 
+		   correct stack frame and we continue to unwind the stack.
+		   This is not quite correct, and will fail for loadable
+		   modules. */
+		sp = info->sp & ~63;
+		do {
+			unsigned long tmp;
+
+			info->prev_sp = sp - 64;
+			info->prev_ip = 0;
+
+			/* Check if stack is inside kernel stack area */
+			if ((info->prev_sp - (unsigned long) task_stack_page(info->t))
+					>= THREAD_SIZE) {
+				info->prev_sp = 0;
+				break;
+			}
+
+			if (copy_from_kernel_nofault(&tmp,
+			    (void *)info->prev_sp - RP_OFFSET, sizeof(tmp)))
+				break;
+			info->prev_ip = tmp;
+			sp = info->prev_sp;
+		} while (!kernel_text_address(info->prev_ip));
+
+		info->rp = 0;
+
+		dbg("analyzing func @ %lx with no unwind info, setting "
+		    "prev_sp=%lx prev_ip=%lx\n", info->ip, 
+		    info->prev_sp, info->prev_ip);
+	} else {
+		dbg("e->start = 0x%x, e->end = 0x%x, Save_SP = %d, "
+		    "Save_RP = %d, Millicode = %d size = %u\n", 
+		    e->region_start, e->region_end, e->Save_SP, e->Save_RP, 
+		    e->Millicode, e->Total_frame_size);
+
+		looking_for_rp = e->Save_RP;
+
+		for (npc = e->region_start; 
+		     (frame_size < (e->Total_frame_size << 3) || 
+		      looking_for_rp) && 
+		     npc < info->ip; 
+		     npc += 4) {
+
+			insn = *(unsigned int *)npc;
+
+			if ((insn & 0xffffc001) == 0x37de0000 ||
+			    (insn & 0xffe00001) == 0x6fc00000) {
+				/* ldo X(sp), sp, or stwm X,D(sp) */
+				frame_size += (insn & 0x3fff) >> 1;
+				dbg("analyzing func @ %lx, insn=%08x @ "
+				    "%lx, frame_size = %ld\n", info->ip,
+				    insn, npc, frame_size);
+			} else if ((insn & 0xffe00009) == 0x73c00008) {
+				/* std,ma X,D(sp) */
+				frame_size += ((insn >> 4) & 0x3ff) << 3;
+				dbg("analyzing func @ %lx, insn=%08x @ "
+				    "%lx, frame_size = %ld\n", info->ip,
+				    insn, npc, frame_size);
+			} else if (insn == 0x6bc23fd9) { 
+				/* stw rp,-20(sp) */
+				rpoffset = 20;
+				looking_for_rp = 0;
+				dbg("analyzing func @ %lx, insn=stw rp,"
+				    "-20(sp) @ %lx\n", info->ip, npc);
+			} else if (insn == 0x0fc212c1) {
+				/* std rp,-16(sr0,sp) */
+				rpoffset = 16;
+				looking_for_rp = 0;
+				dbg("analyzing func @ %lx, insn=std rp,"
+				    "-16(sp) @ %lx\n", info->ip, npc);
+			}
+		}
+
+		if (frame_size > e->Total_frame_size << 3)
+			frame_size = e->Total_frame_size << 3;
+
+		if (!unwind_special(info, e->region_start, frame_size)) {
+			info->prev_sp = info->sp - frame_size;
+			if (e->Millicode)
+				info->rp = info->r31;
+			else if (rpoffset)
+				info->rp = *(unsigned long *)(info->prev_sp - rpoffset);
+			info->prev_ip = info->rp;
+			info->rp = 0;
+		}
+
+		dbg("analyzing func @ %lx, setting prev_sp=%lx "
+		    "prev_ip=%lx npc=%lx\n", info->ip, info->prev_sp, 
+		    info->prev_ip, npc);
+	}
+}
+
+void unwind_frame_init(struct unwind_frame_info *info, struct task_struct *t, 
+		       struct pt_regs *regs)
+{
+	memset(info, 0, sizeof(struct unwind_frame_info));
+	info->t = t;
+	info->sp = regs->gr[30];
+	info->ip = regs->iaoq[0];
+	info->rp = regs->gr[2];
+	info->r31 = regs->gr[31];
+
+	dbg("(%d) Start unwind from sp=%08lx ip=%08lx\n", 
+	    t ? (int)t->pid : -1, info->sp, info->ip);
+}
+
+void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info, struct task_struct *t)
+{
+	struct pt_regs *r = &t->thread.regs;
+	struct pt_regs *r2;
+
+	r2 = kmalloc(sizeof(struct pt_regs), GFP_ATOMIC);
+	if (!r2)
+		return;
+	*r2 = *r;
+	r2->gr[30] = r->ksp;
+	r2->iaoq[0] = r->kpc;
+	unwind_frame_init(info, t, r2);
+	kfree(r2);
+}
+
+#define get_parisc_stackpointer() ({ \
+	unsigned long sp; \
+	__asm__("copy %%r30, %0" : "=r"(sp)); \
+	(sp); \
+})
+
+void unwind_frame_init_task(struct unwind_frame_info *info,
+	struct task_struct *task, struct pt_regs *regs)
+{
+	task = task ? task : current;
+
+	if (task == current) {
+		struct pt_regs r;
+
+		if (!regs) {
+			memset(&r, 0, sizeof(r));
+			r.iaoq[0] =  _THIS_IP_;
+			r.gr[2] = _RET_IP_;
+			r.gr[30] = get_parisc_stackpointer();
+			regs = &r;
+		}
+		unwind_frame_init(info, task, regs);
+	} else {
+		unwind_frame_init_from_blocked_task(info, task);
+	}
+}
+
+int unwind_once(struct unwind_frame_info *next_frame)
+{
+	unwind_frame_regs(next_frame);
+
+	if (next_frame->prev_sp == 0 ||
+	    next_frame->prev_ip == 0)
+		return -1;
+
+	next_frame->sp = next_frame->prev_sp;
+	next_frame->ip = next_frame->prev_ip;
+	next_frame->prev_sp = 0;
+	next_frame->prev_ip = 0;
+
+	dbg("(%d) Continue unwind to sp=%08lx ip=%08lx\n", 
+	    next_frame->t ? (int)next_frame->t->pid : -1, 
+	    next_frame->sp, next_frame->ip);
+
+	return 0;
+}
+
+int unwind_to_user(struct unwind_frame_info *info)
+{
+	int ret;
+	
+	do {
+		ret = unwind_once(info);
+	} while (!ret && !(info->ip & 3));
+
+	return ret;
+}
+
+unsigned long return_address(unsigned int level)
+{
+	struct unwind_frame_info info;
+
+	/* initialize unwind info */
+	unwind_frame_init_task(&info, current, NULL);
+
+	/* unwind stack */
+	level += 2;
+	do {
+		if (unwind_once(&info) < 0 || info.ip == 0)
+			return 0;
+		if (!kernel_text_address(info.ip))
+			return 0;
+	} while (info.ip && level--);
+
+	return info.ip;
+}