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, 543 insertions, 0 deletions

diff --git a/arch/powerpc/mm/ptdump/hashpagetable.c b/arch/powerpc/mm/ptdump/hashpagetable.c
new file mode 100644
index 000000000..9a6015878
--- /dev/null
+++ b/arch/powerpc/mm/ptdump/hashpagetable.c
@@ -0,0 +1,543 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2016, Rashmica Gupta, IBM Corp.
+ *
+ * This traverses the kernel virtual memory and dumps the pages that are in
+ * the hash pagetable, along with their flags to
+ * /sys/kernel/debug/kernel_hash_pagetable.
+ *
+ * If radix is enabled then there is no hash page table and so no debugfs file
+ * is generated.
+ */
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/const.h>
+#include <asm/page.h>
+#include <asm/plpar_wrappers.h>
+#include <linux/memblock.h>
+#include <asm/firmware.h>
+#include <asm/pgalloc.h>
+
+struct pg_state {
+	struct seq_file *seq;
+	const struct addr_marker *marker;
+	unsigned long start_address;
+	unsigned int level;
+	u64 current_flags;
+};
+
+struct addr_marker {
+	unsigned long start_address;
+	const char *name;
+};
+
+static struct addr_marker address_markers[] = {
+	{ 0,	"Start of kernel VM" },
+	{ 0,	"vmalloc() Area" },
+	{ 0,	"vmalloc() End" },
+	{ 0,	"isa I/O start" },
+	{ 0,	"isa I/O end" },
+	{ 0,	"phb I/O start" },
+	{ 0,	"phb I/O end" },
+	{ 0,	"I/O remap start" },
+	{ 0,	"I/O remap end" },
+	{ 0,	"vmemmap start" },
+	{ -1,	NULL },
+};
+
+struct flag_info {
+	u64		mask;
+	u64		val;
+	const char	*set;
+	const char	*clear;
+	bool		is_val;
+	int		shift;
+};
+
+static const struct flag_info v_flag_array[] = {
+	{
+		.mask   = SLB_VSID_B,
+		.val    = SLB_VSID_B_256M,
+		.set    = "ssize: 256M",
+		.clear  = "ssize: 1T  ",
+	}, {
+		.mask	= HPTE_V_SECONDARY,
+		.val	= HPTE_V_SECONDARY,
+		.set	= "secondary",
+		.clear	= "primary  ",
+	}, {
+		.mask	= HPTE_V_VALID,
+		.val	= HPTE_V_VALID,
+		.set	= "valid  ",
+		.clear	= "invalid",
+	}, {
+		.mask	= HPTE_V_BOLTED,
+		.val	= HPTE_V_BOLTED,
+		.set	= "bolted",
+		.clear	= "",
+	}
+};
+
+static const struct flag_info r_flag_array[] = {
+	{
+		.mask	= HPTE_R_PP0 | HPTE_R_PP,
+		.val	= PP_RWXX,
+		.set	= "prot:RW--",
+	}, {
+		.mask	= HPTE_R_PP0 | HPTE_R_PP,
+		.val	= PP_RWRX,
+		.set	= "prot:RWR-",
+	}, {
+		.mask	= HPTE_R_PP0 | HPTE_R_PP,
+		.val	= PP_RWRW,
+		.set	= "prot:RWRW",
+	}, {
+		.mask	= HPTE_R_PP0 | HPTE_R_PP,
+		.val	= PP_RXRX,
+		.set	= "prot:R-R-",
+	}, {
+		.mask	= HPTE_R_PP0 | HPTE_R_PP,
+		.val	= PP_RXXX,
+		.set	= "prot:R---",
+	}, {
+		.mask	= HPTE_R_KEY_HI | HPTE_R_KEY_LO,
+		.val	= HPTE_R_KEY_HI | HPTE_R_KEY_LO,
+		.set	= "key",
+		.clear	= "",
+		.is_val = true,
+	}, {
+		.mask	= HPTE_R_R,
+		.val	= HPTE_R_R,
+		.set	= "ref",
+		.clear	= "   ",
+	}, {
+		.mask	= HPTE_R_C,
+		.val	= HPTE_R_C,
+		.set	= "changed",
+		.clear	= "       ",
+	}, {
+		.mask	= HPTE_R_N,
+		.val	= HPTE_R_N,
+		.set	= "no execute",
+	}, {
+		.mask	= HPTE_R_WIMG,
+		.val	= HPTE_R_W,
+		.set	= "writethru",
+	}, {
+		.mask	= HPTE_R_WIMG,
+		.val	= HPTE_R_I,
+		.set	= "no cache",
+	}, {
+		.mask	= HPTE_R_WIMG,
+		.val	= HPTE_R_G,
+		.set	= "guarded",
+	}
+};
+
+static int calculate_pagesize(struct pg_state *st, int ps, char s[])
+{
+	static const char units[] = "BKMGTPE";
+	const char *unit = units;
+
+	while (ps > 9 && unit[1]) {
+		ps -= 10;
+		unit++;
+	}
+	seq_printf(st->seq, "  %s_ps: %i%c\t", s, 1<<ps, *unit);
+	return ps;
+}
+
+static void dump_flag_info(struct pg_state *st, const struct flag_info
+		*flag, u64 pte, int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++, flag++) {
+		const char *s = NULL;
+		u64 val;
+
+		/* flag not defined so don't check it */
+		if (flag->mask == 0)
+			continue;
+		/* Some 'flags' are actually values */
+		if (flag->is_val) {
+			val = pte & flag->val;
+			if (flag->shift)
+				val = val >> flag->shift;
+			seq_printf(st->seq, "  %s:%llx", flag->set, val);
+		} else {
+			if ((pte & flag->mask) == flag->val)
+				s = flag->set;
+			else
+				s = flag->clear;
+			if (s)
+				seq_printf(st->seq, "  %s", s);
+		}
+	}
+}
+
+static void dump_hpte_info(struct pg_state *st, unsigned long ea, u64 v, u64 r,
+		unsigned long rpn, int bps, int aps, unsigned long lp)
+{
+	int aps_index;
+
+	while (ea >= st->marker[1].start_address) {
+		st->marker++;
+		seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
+	}
+	seq_printf(st->seq, "0x%lx:\t", ea);
+	seq_printf(st->seq, "AVPN:%llx\t", HPTE_V_AVPN_VAL(v));
+	dump_flag_info(st, v_flag_array, v, ARRAY_SIZE(v_flag_array));
+	seq_printf(st->seq, "  rpn: %lx\t", rpn);
+	dump_flag_info(st, r_flag_array, r, ARRAY_SIZE(r_flag_array));
+
+	calculate_pagesize(st, bps, "base");
+	aps_index = calculate_pagesize(st, aps, "actual");
+	if (aps_index != 2)
+		seq_printf(st->seq, "LP enc: %lx", lp);
+	seq_putc(st->seq, '\n');
+}
+
+
+static int native_find(unsigned long ea, int psize, bool primary, u64 *v, u64
+		*r)
+{
+	struct hash_pte *hptep;
+	unsigned long hash, vsid, vpn, hpte_group, want_v, hpte_v;
+	int i, ssize = mmu_kernel_ssize;
+	unsigned long shift = mmu_psize_defs[psize].shift;
+
+	/* calculate hash */
+	vsid = get_kernel_vsid(ea, ssize);
+	vpn  = hpt_vpn(ea, vsid, ssize);
+	hash = hpt_hash(vpn, shift, ssize);
+	want_v = hpte_encode_avpn(vpn, psize, ssize);
+
+	/* to check in the secondary hash table, we invert the hash */
+	if (!primary)
+		hash = ~hash;
+	hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+	for (i = 0; i < HPTES_PER_GROUP; i++) {
+		hptep = htab_address + hpte_group;
+		hpte_v = be64_to_cpu(hptep->v);
+
+		if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) {
+			/* HPTE matches */
+			*v = be64_to_cpu(hptep->v);
+			*r = be64_to_cpu(hptep->r);
+			return 0;
+		}
+		++hpte_group;
+	}
+	return -1;
+}
+
+static int pseries_find(unsigned long ea, int psize, bool primary, u64 *v, u64 *r)
+{
+	struct {
+		unsigned long v;
+		unsigned long r;
+	} ptes[4];
+	unsigned long vsid, vpn, hash, hpte_group, want_v;
+	int i, j, ssize = mmu_kernel_ssize;
+	long lpar_rc = 0;
+	unsigned long shift = mmu_psize_defs[psize].shift;
+
+	/* calculate hash */
+	vsid = get_kernel_vsid(ea, ssize);
+	vpn  = hpt_vpn(ea, vsid, ssize);
+	hash = hpt_hash(vpn, shift, ssize);
+	want_v = hpte_encode_avpn(vpn, psize, ssize);
+
+	/* to check in the secondary hash table, we invert the hash */
+	if (!primary)
+		hash = ~hash;
+	hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+	/* see if we can find an entry in the hpte with this hash */
+	for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) {
+		lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes);
+
+		if (lpar_rc)
+			continue;
+		for (j = 0; j < 4; j++) {
+			if (HPTE_V_COMPARE(ptes[j].v, want_v) &&
+					(ptes[j].v & HPTE_V_VALID)) {
+				/* HPTE matches */
+				*v = ptes[j].v;
+				*r = ptes[j].r;
+				return 0;
+			}
+		}
+	}
+	return -1;
+}
+
+static void decode_r(int bps, unsigned long r, unsigned long *rpn, int *aps,
+		unsigned long *lp_bits)
+{
+	struct mmu_psize_def entry;
+	unsigned long arpn, mask, lp;
+	int penc = -2, idx = 0, shift;
+
+	/*.
+	 * The LP field has 8 bits. Depending on the actual page size, some of
+	 * these bits are concatenated with the APRN to get the RPN. The rest
+	 * of the bits in the LP field is the LP value and is an encoding for
+	 * the base page size and the actual page size.
+	 *
+	 *  -	find the mmu entry for our base page size
+	 *  -	go through all page encodings and use the associated mask to
+	 *	find an encoding that matches our encoding in the LP field.
+	 */
+	arpn = (r & HPTE_R_RPN) >> HPTE_R_RPN_SHIFT;
+	lp = arpn & 0xff;
+
+	entry = mmu_psize_defs[bps];
+	while (idx < MMU_PAGE_COUNT) {
+		penc = entry.penc[idx];
+		if ((penc != -1) && (mmu_psize_defs[idx].shift)) {
+			shift = mmu_psize_defs[idx].shift -  HPTE_R_RPN_SHIFT;
+			mask = (0x1 << (shift)) - 1;
+			if ((lp & mask) == penc) {
+				*aps = mmu_psize_to_shift(idx);
+				*lp_bits = lp & mask;
+				*rpn = arpn >> shift;
+				return;
+			}
+		}
+		idx++;
+	}
+}
+
+static int base_hpte_find(unsigned long ea, int psize, bool primary, u64 *v,
+			  u64 *r)
+{
+	if (IS_ENABLED(CONFIG_PPC_PSERIES) && firmware_has_feature(FW_FEATURE_LPAR))
+		return pseries_find(ea, psize, primary, v, r);
+
+	return native_find(ea, psize, primary, v, r);
+}
+
+static unsigned long hpte_find(struct pg_state *st, unsigned long ea, int psize)
+{
+	unsigned long slot;
+	u64 v  = 0, r = 0;
+	unsigned long rpn, lp_bits;
+	int base_psize = 0, actual_psize = 0;
+
+	if (ea < PAGE_OFFSET)
+		return -1;
+
+	/* Look in primary table */
+	slot = base_hpte_find(ea, psize, true, &v, &r);
+
+	/* Look in secondary table */
+	if (slot == -1)
+		slot = base_hpte_find(ea, psize, false, &v, &r);
+
+	/* No entry found */
+	if (slot == -1)
+		return -1;
+
+	/*
+	 * We found an entry in the hash page table:
+	 *  - check that this has the same base page
+	 *  - find the actual page size
+	 *  - find the RPN
+	 */
+	base_psize = mmu_psize_to_shift(psize);
+
+	if ((v & HPTE_V_LARGE) == HPTE_V_LARGE) {
+		decode_r(psize, r, &rpn, &actual_psize, &lp_bits);
+	} else {
+		/* 4K actual page size */
+		actual_psize = 12;
+		rpn = (r & HPTE_R_RPN) >> HPTE_R_RPN_SHIFT;
+		/* In this case there are no LP bits */
+		lp_bits = -1;
+	}
+	/*
+	 * We didn't find a matching encoding, so the PTE we found isn't for
+	 * this address.
+	 */
+	if (actual_psize == -1)
+		return -1;
+
+	dump_hpte_info(st, ea, v, r, rpn, base_psize, actual_psize, lp_bits);
+	return 0;
+}
+
+static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start)
+{
+	pte_t *pte = pte_offset_kernel(pmd, 0);
+	unsigned long addr, pteval, psize;
+	int i, status;
+
+	for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
+		addr = start + i * PAGE_SIZE;
+		pteval = pte_val(*pte);
+
+		if (addr < VMALLOC_END)
+			psize = mmu_vmalloc_psize;
+		else
+			psize = mmu_io_psize;
+
+		/* check for secret 4K mappings */
+		if (IS_ENABLED(CONFIG_PPC_64K_PAGES) &&
+		    ((pteval & H_PAGE_COMBO) == H_PAGE_COMBO ||
+		     (pteval & H_PAGE_4K_PFN) == H_PAGE_4K_PFN))
+			psize = mmu_io_psize;
+
+		/* check for hashpte */
+		status = hpte_find(st, addr, psize);
+
+		if (((pteval & H_PAGE_HASHPTE) != H_PAGE_HASHPTE)
+				&& (status != -1)) {
+		/* found a hpte that is not in the linux page tables */
+			seq_printf(st->seq, "page probably bolted before linux"
+				" pagetables were set: addr:%lx, pteval:%lx\n",
+				addr, pteval);
+		}
+	}
+}
+
+static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
+{
+	pmd_t *pmd = pmd_offset(pud, 0);
+	unsigned long addr;
+	unsigned int i;
+
+	for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
+		addr = start + i * PMD_SIZE;
+		if (!pmd_none(*pmd))
+			/* pmd exists */
+			walk_pte(st, pmd, addr);
+	}
+}
+
+static void walk_pud(struct pg_state *st, p4d_t *p4d, unsigned long start)
+{
+	pud_t *pud = pud_offset(p4d, 0);
+	unsigned long addr;
+	unsigned int i;
+
+	for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
+		addr = start + i * PUD_SIZE;
+		if (!pud_none(*pud))
+			/* pud exists */
+			walk_pmd(st, pud, addr);
+	}
+}
+
+static void walk_p4d(struct pg_state *st, pgd_t *pgd, unsigned long start)
+{
+	p4d_t *p4d = p4d_offset(pgd, 0);
+	unsigned long addr;
+	unsigned int i;
+
+	for (i = 0; i < PTRS_PER_P4D; i++, p4d++) {
+		addr = start + i * P4D_SIZE;
+		if (!p4d_none(*p4d))
+			/* p4d exists */
+			walk_pud(st, p4d, addr);
+	}
+}
+
+static void walk_pagetables(struct pg_state *st)
+{
+	pgd_t *pgd = pgd_offset_k(0UL);
+	unsigned int i;
+	unsigned long addr;
+
+	/*
+	 * Traverse the linux pagetable structure and dump pages that are in
+	 * the hash pagetable.
+	 */
+	for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
+		addr = KERN_VIRT_START + i * PGDIR_SIZE;
+		if (!pgd_none(*pgd))
+			/* pgd exists */
+			walk_p4d(st, pgd, addr);
+	}
+}
+
+
+static void walk_linearmapping(struct pg_state *st)
+{
+	unsigned long addr;
+
+	/*
+	 * Traverse the linear mapping section of virtual memory and dump pages
+	 * that are in the hash pagetable.
+	 */
+	unsigned long psize = 1 << mmu_psize_defs[mmu_linear_psize].shift;
+
+	for (addr = PAGE_OFFSET; addr < PAGE_OFFSET +
+			memblock_end_of_DRAM(); addr += psize)
+		hpte_find(st, addr, mmu_linear_psize);
+}
+
+static void walk_vmemmap(struct pg_state *st)
+{
+	struct vmemmap_backing *ptr = vmemmap_list;
+
+	if (!IS_ENABLED(CONFIG_SPARSEMEM_VMEMMAP))
+		return;
+	/*
+	 * Traverse the vmemmaped memory and dump pages that are in the hash
+	 * pagetable.
+	 */
+	while (ptr->list) {
+		hpte_find(st, ptr->virt_addr, mmu_vmemmap_psize);
+		ptr = ptr->list;
+	}
+	seq_puts(st->seq, "---[ vmemmap end ]---\n");
+}
+
+static void populate_markers(void)
+{
+	address_markers[0].start_address = PAGE_OFFSET;
+	address_markers[1].start_address = VMALLOC_START;
+	address_markers[2].start_address = VMALLOC_END;
+	address_markers[3].start_address = ISA_IO_BASE;
+	address_markers[4].start_address = ISA_IO_END;
+	address_markers[5].start_address = PHB_IO_BASE;
+	address_markers[6].start_address = PHB_IO_END;
+	address_markers[7].start_address = IOREMAP_BASE;
+	address_markers[8].start_address = IOREMAP_END;
+	address_markers[9].start_address =  H_VMEMMAP_START;
+}
+
+static int ptdump_show(struct seq_file *m, void *v)
+{
+	struct pg_state st = {
+		.seq = m,
+		.start_address = PAGE_OFFSET,
+		.marker = address_markers,
+	};
+	/*
+	 * Traverse the 0xc, 0xd and 0xf areas of the kernel virtual memory and
+	 * dump pages that are in the hash pagetable.
+	 */
+	walk_linearmapping(&st);
+	walk_pagetables(&st);
+	walk_vmemmap(&st);
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(ptdump);
+
+static int ptdump_init(void)
+{
+	if (!radix_enabled()) {
+		populate_markers();
+		debugfs_create_file("kernel_hash_pagetable", 0400, NULL, NULL,
+				    &ptdump_fops);
+	}
+	return 0;
+}
+device_initcall(ptdump_init);