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, 569 insertions, 0 deletions

diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c
new file mode 100644
index 000000000..f90d2c276
--- /dev/null
+++ b/lib/test_vmalloc.c
@@ -0,0 +1,569 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Test module for stress and analyze performance of vmalloc allocator.
+ * (C) 2018 Uladzislau Rezki (Sony) <urezki@gmail.com>
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/random.h>
+#include <linux/kthread.h>
+#include <linux/moduleparam.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/rwsem.h>
+#include <linux/mm.h>
+#include <linux/rcupdate.h>
+#include <linux/slab.h>
+
+#define __param(type, name, init, msg)		\
+	static type name = init;				\
+	module_param(name, type, 0444);			\
+	MODULE_PARM_DESC(name, msg)				\
+
+__param(int, nr_threads, 0,
+	"Number of workers to perform tests(min: 1 max: USHRT_MAX)");
+
+__param(bool, sequential_test_order, false,
+	"Use sequential stress tests order");
+
+__param(int, test_repeat_count, 1,
+	"Set test repeat counter");
+
+__param(int, test_loop_count, 1000000,
+	"Set test loop counter");
+
+__param(int, nr_pages, 0,
+	"Set number of pages for fix_size_alloc_test(default: 1)");
+
+__param(int, run_test_mask, INT_MAX,
+	"Set tests specified in the mask.\n\n"
+		"\t\tid: 1,    name: fix_size_alloc_test\n"
+		"\t\tid: 2,    name: full_fit_alloc_test\n"
+		"\t\tid: 4,    name: long_busy_list_alloc_test\n"
+		"\t\tid: 8,    name: random_size_alloc_test\n"
+		"\t\tid: 16,   name: fix_align_alloc_test\n"
+		"\t\tid: 32,   name: random_size_align_alloc_test\n"
+		"\t\tid: 64,   name: align_shift_alloc_test\n"
+		"\t\tid: 128,  name: pcpu_alloc_test\n"
+		"\t\tid: 256,  name: kvfree_rcu_1_arg_vmalloc_test\n"
+		"\t\tid: 512,  name: kvfree_rcu_2_arg_vmalloc_test\n"
+		/* Add a new test case description here. */
+);
+
+/*
+ * Read write semaphore for synchronization of setup
+ * phase that is done in main thread and workers.
+ */
+static DECLARE_RWSEM(prepare_for_test_rwsem);
+
+/*
+ * Completion tracking for worker threads.
+ */
+static DECLARE_COMPLETION(test_all_done_comp);
+static atomic_t test_n_undone = ATOMIC_INIT(0);
+
+static inline void
+test_report_one_done(void)
+{
+	if (atomic_dec_and_test(&test_n_undone))
+		complete(&test_all_done_comp);
+}
+
+static int random_size_align_alloc_test(void)
+{
+	unsigned long size, align;
+	unsigned int rnd;
+	void *ptr;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		rnd = get_random_u8();
+
+		/*
+		 * Maximum 1024 pages, if PAGE_SIZE is 4096.
+		 */
+		align = 1 << (rnd % 23);
+
+		/*
+		 * Maximum 10 pages.
+		 */
+		size = ((rnd % 10) + 1) * PAGE_SIZE;
+
+		ptr = __vmalloc_node(size, align, GFP_KERNEL | __GFP_ZERO, 0,
+				__builtin_return_address(0));
+		if (!ptr)
+			return -1;
+
+		vfree(ptr);
+	}
+
+	return 0;
+}
+
+/*
+ * This test case is supposed to be failed.
+ */
+static int align_shift_alloc_test(void)
+{
+	unsigned long align;
+	void *ptr;
+	int i;
+
+	for (i = 0; i < BITS_PER_LONG; i++) {
+		align = ((unsigned long) 1) << i;
+
+		ptr = __vmalloc_node(PAGE_SIZE, align, GFP_KERNEL|__GFP_ZERO, 0,
+				__builtin_return_address(0));
+		if (!ptr)
+			return -1;
+
+		vfree(ptr);
+	}
+
+	return 0;
+}
+
+static int fix_align_alloc_test(void)
+{
+	void *ptr;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		ptr = __vmalloc_node(5 * PAGE_SIZE, THREAD_ALIGN << 1,
+				GFP_KERNEL | __GFP_ZERO, 0,
+				__builtin_return_address(0));
+		if (!ptr)
+			return -1;
+
+		vfree(ptr);
+	}
+
+	return 0;
+}
+
+static int random_size_alloc_test(void)
+{
+	unsigned int n;
+	void *p;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		n = get_random_u32_inclusive(1, 100);
+		p = vmalloc(n * PAGE_SIZE);
+
+		if (!p)
+			return -1;
+
+		*((__u8 *)p) = 1;
+		vfree(p);
+	}
+
+	return 0;
+}
+
+static int long_busy_list_alloc_test(void)
+{
+	void *ptr_1, *ptr_2;
+	void **ptr;
+	int rv = -1;
+	int i;
+
+	ptr = vmalloc(sizeof(void *) * 15000);
+	if (!ptr)
+		return rv;
+
+	for (i = 0; i < 15000; i++)
+		ptr[i] = vmalloc(1 * PAGE_SIZE);
+
+	for (i = 0; i < test_loop_count; i++) {
+		ptr_1 = vmalloc(100 * PAGE_SIZE);
+		if (!ptr_1)
+			goto leave;
+
+		ptr_2 = vmalloc(1 * PAGE_SIZE);
+		if (!ptr_2) {
+			vfree(ptr_1);
+			goto leave;
+		}
+
+		*((__u8 *)ptr_1) = 0;
+		*((__u8 *)ptr_2) = 1;
+
+		vfree(ptr_1);
+		vfree(ptr_2);
+	}
+
+	/*  Success */
+	rv = 0;
+
+leave:
+	for (i = 0; i < 15000; i++)
+		vfree(ptr[i]);
+
+	vfree(ptr);
+	return rv;
+}
+
+static int full_fit_alloc_test(void)
+{
+	void **ptr, **junk_ptr, *tmp;
+	int junk_length;
+	int rv = -1;
+	int i;
+
+	junk_length = fls(num_online_cpus());
+	junk_length *= (32 * 1024 * 1024 / PAGE_SIZE);
+
+	ptr = vmalloc(sizeof(void *) * junk_length);
+	if (!ptr)
+		return rv;
+
+	junk_ptr = vmalloc(sizeof(void *) * junk_length);
+	if (!junk_ptr) {
+		vfree(ptr);
+		return rv;
+	}
+
+	for (i = 0; i < junk_length; i++) {
+		ptr[i] = vmalloc(1 * PAGE_SIZE);
+		junk_ptr[i] = vmalloc(1 * PAGE_SIZE);
+	}
+
+	for (i = 0; i < junk_length; i++)
+		vfree(junk_ptr[i]);
+
+	for (i = 0; i < test_loop_count; i++) {
+		tmp = vmalloc(1 * PAGE_SIZE);
+
+		if (!tmp)
+			goto error;
+
+		*((__u8 *)tmp) = 1;
+		vfree(tmp);
+	}
+
+	/* Success */
+	rv = 0;
+
+error:
+	for (i = 0; i < junk_length; i++)
+		vfree(ptr[i]);
+
+	vfree(ptr);
+	vfree(junk_ptr);
+
+	return rv;
+}
+
+static int fix_size_alloc_test(void)
+{
+	void *ptr;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		ptr = vmalloc((nr_pages > 0 ? nr_pages:1) * PAGE_SIZE);
+
+		if (!ptr)
+			return -1;
+
+		*((__u8 *)ptr) = 0;
+
+		vfree(ptr);
+	}
+
+	return 0;
+}
+
+static int
+pcpu_alloc_test(void)
+{
+	int rv = 0;
+#ifndef CONFIG_NEED_PER_CPU_KM
+	void __percpu **pcpu;
+	size_t size, align;
+	int i;
+
+	pcpu = vmalloc(sizeof(void __percpu *) * 35000);
+	if (!pcpu)
+		return -1;
+
+	for (i = 0; i < 35000; i++) {
+		size = get_random_u32_inclusive(1, PAGE_SIZE / 4);
+
+		/*
+		 * Maximum PAGE_SIZE
+		 */
+		align = 1 << get_random_u32_inclusive(1, 11);
+
+		pcpu[i] = __alloc_percpu(size, align);
+		if (!pcpu[i])
+			rv = -1;
+	}
+
+	for (i = 0; i < 35000; i++)
+		free_percpu(pcpu[i]);
+
+	vfree(pcpu);
+#endif
+	return rv;
+}
+
+struct test_kvfree_rcu {
+	struct rcu_head rcu;
+	unsigned char array[20];
+};
+
+static int
+kvfree_rcu_1_arg_vmalloc_test(void)
+{
+	struct test_kvfree_rcu *p;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		p = vmalloc(1 * PAGE_SIZE);
+		if (!p)
+			return -1;
+
+		p->array[0] = 'a';
+		kvfree_rcu(p);
+	}
+
+	return 0;
+}
+
+static int
+kvfree_rcu_2_arg_vmalloc_test(void)
+{
+	struct test_kvfree_rcu *p;
+	int i;
+
+	for (i = 0; i < test_loop_count; i++) {
+		p = vmalloc(1 * PAGE_SIZE);
+		if (!p)
+			return -1;
+
+		p->array[0] = 'a';
+		kvfree_rcu(p, rcu);
+	}
+
+	return 0;
+}
+
+struct test_case_desc {
+	const char *test_name;
+	int (*test_func)(void);
+};
+
+static struct test_case_desc test_case_array[] = {
+	{ "fix_size_alloc_test", fix_size_alloc_test },
+	{ "full_fit_alloc_test", full_fit_alloc_test },
+	{ "long_busy_list_alloc_test", long_busy_list_alloc_test },
+	{ "random_size_alloc_test", random_size_alloc_test },
+	{ "fix_align_alloc_test", fix_align_alloc_test },
+	{ "random_size_align_alloc_test", random_size_align_alloc_test },
+	{ "align_shift_alloc_test", align_shift_alloc_test },
+	{ "pcpu_alloc_test", pcpu_alloc_test },
+	{ "kvfree_rcu_1_arg_vmalloc_test", kvfree_rcu_1_arg_vmalloc_test },
+	{ "kvfree_rcu_2_arg_vmalloc_test", kvfree_rcu_2_arg_vmalloc_test },
+	/* Add a new test case here. */
+};
+
+struct test_case_data {
+	int test_failed;
+	int test_passed;
+	u64 time;
+};
+
+static struct test_driver {
+	struct task_struct *task;
+	struct test_case_data data[ARRAY_SIZE(test_case_array)];
+
+	unsigned long start;
+	unsigned long stop;
+} *tdriver;
+
+static void shuffle_array(int *arr, int n)
+{
+	int i, j;
+
+	for (i = n - 1; i > 0; i--)  {
+		/* Cut the range. */
+		j = get_random_u32_below(i);
+
+		/* Swap indexes. */
+		swap(arr[i], arr[j]);
+	}
+}
+
+static int test_func(void *private)
+{
+	struct test_driver *t = private;
+	int random_array[ARRAY_SIZE(test_case_array)];
+	int index, i, j;
+	ktime_t kt;
+	u64 delta;
+
+	for (i = 0; i < ARRAY_SIZE(test_case_array); i++)
+		random_array[i] = i;
+
+	if (!sequential_test_order)
+		shuffle_array(random_array, ARRAY_SIZE(test_case_array));
+
+	/*
+	 * Block until initialization is done.
+	 */
+	down_read(&prepare_for_test_rwsem);
+
+	t->start = get_cycles();
+	for (i = 0; i < ARRAY_SIZE(test_case_array); i++) {
+		index = random_array[i];
+
+		/*
+		 * Skip tests if run_test_mask has been specified.
+		 */
+		if (!((run_test_mask & (1 << index)) >> index))
+			continue;
+
+		kt = ktime_get();
+		for (j = 0; j < test_repeat_count; j++) {
+			if (!test_case_array[index].test_func())
+				t->data[index].test_passed++;
+			else
+				t->data[index].test_failed++;
+		}
+
+		/*
+		 * Take an average time that test took.
+		 */
+		delta = (u64) ktime_us_delta(ktime_get(), kt);
+		do_div(delta, (u32) test_repeat_count);
+
+		t->data[index].time = delta;
+	}
+	t->stop = get_cycles();
+
+	up_read(&prepare_for_test_rwsem);
+	test_report_one_done();
+
+	/*
+	 * Wait for the kthread_stop() call.
+	 */
+	while (!kthread_should_stop())
+		msleep(10);
+
+	return 0;
+}
+
+static int
+init_test_configurtion(void)
+{
+	/*
+	 * A maximum number of workers is defined as hard-coded
+	 * value and set to USHRT_MAX. We add such gap just in
+	 * case and for potential heavy stressing.
+	 */
+	nr_threads = clamp(nr_threads, 1, (int) USHRT_MAX);
+
+	/* Allocate the space for test instances. */
+	tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL);
+	if (tdriver == NULL)
+		return -1;
+
+	if (test_repeat_count <= 0)
+		test_repeat_count = 1;
+
+	if (test_loop_count <= 0)
+		test_loop_count = 1;
+
+	return 0;
+}
+
+static void do_concurrent_test(void)
+{
+	int i, ret;
+
+	/*
+	 * Set some basic configurations plus sanity check.
+	 */
+	ret = init_test_configurtion();
+	if (ret < 0)
+		return;
+
+	/*
+	 * Put on hold all workers.
+	 */
+	down_write(&prepare_for_test_rwsem);
+
+	for (i = 0; i < nr_threads; i++) {
+		struct test_driver *t = &tdriver[i];
+
+		t->task = kthread_run(test_func, t, "vmalloc_test/%d", i);
+
+		if (!IS_ERR(t->task))
+			/* Success. */
+			atomic_inc(&test_n_undone);
+		else
+			pr_err("Failed to start %d kthread\n", i);
+	}
+
+	/*
+	 * Now let the workers do their job.
+	 */
+	up_write(&prepare_for_test_rwsem);
+
+	/*
+	 * Sleep quiet until all workers are done with 1 second
+	 * interval. Since the test can take a lot of time we
+	 * can run into a stack trace of the hung task. That is
+	 * why we go with completion_timeout and HZ value.
+	 */
+	do {
+		ret = wait_for_completion_timeout(&test_all_done_comp, HZ);
+	} while (!ret);
+
+	for (i = 0; i < nr_threads; i++) {
+		struct test_driver *t = &tdriver[i];
+		int j;
+
+		if (!IS_ERR(t->task))
+			kthread_stop(t->task);
+
+		for (j = 0; j < ARRAY_SIZE(test_case_array); j++) {
+			if (!((run_test_mask & (1 << j)) >> j))
+				continue;
+
+			pr_info(
+				"Summary: %s passed: %d failed: %d repeat: %d loops: %d avg: %llu usec\n",
+				test_case_array[j].test_name,
+				t->data[j].test_passed,
+				t->data[j].test_failed,
+				test_repeat_count, test_loop_count,
+				t->data[j].time);
+		}
+
+		pr_info("All test took worker%d=%lu cycles\n",
+			i, t->stop - t->start);
+	}
+
+	kvfree(tdriver);
+}
+
+static int vmalloc_test_init(void)
+{
+	do_concurrent_test();
+	return -EAGAIN; /* Fail will directly unload the module */
+}
+
+static void vmalloc_test_exit(void)
+{
+}
+
+module_init(vmalloc_test_init)
+module_exit(vmalloc_test_exit)
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Uladzislau Rezki");
+MODULE_DESCRIPTION("vmalloc test module");