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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/test_lockup.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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(). ...
Diffstat (limited to '')
-rw-r--r--lib/test_lockup.c620
1 files changed, 620 insertions, 0 deletions
diff --git a/lib/test_lockup.c b/lib/test_lockup.c
new file mode 100644
index 000000000..c3fd87d6c
--- /dev/null
+++ b/lib/test_lockup.c
@@ -0,0 +1,620 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test module to generate lockups
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/sched/signal.h>
+#include <linux/sched/clock.h>
+#include <linux/cpu.h>
+#include <linux/nmi.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/file.h>
+
+static unsigned int time_secs;
+module_param(time_secs, uint, 0600);
+MODULE_PARM_DESC(time_secs, "lockup time in seconds, default 0");
+
+static unsigned int time_nsecs;
+module_param(time_nsecs, uint, 0600);
+MODULE_PARM_DESC(time_nsecs, "nanoseconds part of lockup time, default 0");
+
+static unsigned int cooldown_secs;
+module_param(cooldown_secs, uint, 0600);
+MODULE_PARM_DESC(cooldown_secs, "cooldown time between iterations in seconds, default 0");
+
+static unsigned int cooldown_nsecs;
+module_param(cooldown_nsecs, uint, 0600);
+MODULE_PARM_DESC(cooldown_nsecs, "nanoseconds part of cooldown, default 0");
+
+static unsigned int iterations = 1;
+module_param(iterations, uint, 0600);
+MODULE_PARM_DESC(iterations, "lockup iterations, default 1");
+
+static bool all_cpus;
+module_param(all_cpus, bool, 0400);
+MODULE_PARM_DESC(all_cpus, "trigger lockup at all cpus at once");
+
+static int wait_state;
+static char *state = "R";
+module_param(state, charp, 0400);
+MODULE_PARM_DESC(state, "wait in 'R' running (default), 'D' uninterruptible, 'K' killable, 'S' interruptible state");
+
+static bool use_hrtimer;
+module_param(use_hrtimer, bool, 0400);
+MODULE_PARM_DESC(use_hrtimer, "use high-resolution timer for sleeping");
+
+static bool iowait;
+module_param(iowait, bool, 0400);
+MODULE_PARM_DESC(iowait, "account sleep time as iowait");
+
+static bool lock_read;
+module_param(lock_read, bool, 0400);
+MODULE_PARM_DESC(lock_read, "lock read-write locks for read");
+
+static bool lock_single;
+module_param(lock_single, bool, 0400);
+MODULE_PARM_DESC(lock_single, "acquire locks only at one cpu");
+
+static bool reacquire_locks;
+module_param(reacquire_locks, bool, 0400);
+MODULE_PARM_DESC(reacquire_locks, "release and reacquire locks/irq/preempt between iterations");
+
+static bool touch_softlockup;
+module_param(touch_softlockup, bool, 0600);
+MODULE_PARM_DESC(touch_softlockup, "touch soft-lockup watchdog between iterations");
+
+static bool touch_hardlockup;
+module_param(touch_hardlockup, bool, 0600);
+MODULE_PARM_DESC(touch_hardlockup, "touch hard-lockup watchdog between iterations");
+
+static bool call_cond_resched;
+module_param(call_cond_resched, bool, 0600);
+MODULE_PARM_DESC(call_cond_resched, "call cond_resched() between iterations");
+
+static bool measure_lock_wait;
+module_param(measure_lock_wait, bool, 0400);
+MODULE_PARM_DESC(measure_lock_wait, "measure lock wait time");
+
+static unsigned long lock_wait_threshold = ULONG_MAX;
+module_param(lock_wait_threshold, ulong, 0400);
+MODULE_PARM_DESC(lock_wait_threshold, "print lock wait time longer than this in nanoseconds, default off");
+
+static bool test_disable_irq;
+module_param_named(disable_irq, test_disable_irq, bool, 0400);
+MODULE_PARM_DESC(disable_irq, "disable interrupts: generate hard-lockups");
+
+static bool disable_softirq;
+module_param(disable_softirq, bool, 0400);
+MODULE_PARM_DESC(disable_softirq, "disable bottom-half irq handlers");
+
+static bool disable_preempt;
+module_param(disable_preempt, bool, 0400);
+MODULE_PARM_DESC(disable_preempt, "disable preemption: generate soft-lockups");
+
+static bool lock_rcu;
+module_param(lock_rcu, bool, 0400);
+MODULE_PARM_DESC(lock_rcu, "grab rcu_read_lock: generate rcu stalls");
+
+static bool lock_mmap_sem;
+module_param(lock_mmap_sem, bool, 0400);
+MODULE_PARM_DESC(lock_mmap_sem, "lock mm->mmap_lock: block procfs interfaces");
+
+static unsigned long lock_rwsem_ptr;
+module_param_unsafe(lock_rwsem_ptr, ulong, 0400);
+MODULE_PARM_DESC(lock_rwsem_ptr, "lock rw_semaphore at address");
+
+static unsigned long lock_mutex_ptr;
+module_param_unsafe(lock_mutex_ptr, ulong, 0400);
+MODULE_PARM_DESC(lock_mutex_ptr, "lock mutex at address");
+
+static unsigned long lock_spinlock_ptr;
+module_param_unsafe(lock_spinlock_ptr, ulong, 0400);
+MODULE_PARM_DESC(lock_spinlock_ptr, "lock spinlock at address");
+
+static unsigned long lock_rwlock_ptr;
+module_param_unsafe(lock_rwlock_ptr, ulong, 0400);
+MODULE_PARM_DESC(lock_rwlock_ptr, "lock rwlock at address");
+
+static unsigned int alloc_pages_nr;
+module_param_unsafe(alloc_pages_nr, uint, 0600);
+MODULE_PARM_DESC(alloc_pages_nr, "allocate and free pages under locks");
+
+static unsigned int alloc_pages_order;
+module_param(alloc_pages_order, uint, 0400);
+MODULE_PARM_DESC(alloc_pages_order, "page order to allocate");
+
+static gfp_t alloc_pages_gfp = GFP_KERNEL;
+module_param_unsafe(alloc_pages_gfp, uint, 0400);
+MODULE_PARM_DESC(alloc_pages_gfp, "allocate pages with this gfp_mask, default GFP_KERNEL");
+
+static bool alloc_pages_atomic;
+module_param(alloc_pages_atomic, bool, 0400);
+MODULE_PARM_DESC(alloc_pages_atomic, "allocate pages with GFP_ATOMIC");
+
+static bool reallocate_pages;
+module_param(reallocate_pages, bool, 0400);
+MODULE_PARM_DESC(reallocate_pages, "free and allocate pages between iterations");
+
+struct file *test_file;
+static struct inode *test_inode;
+static char test_file_path[256];
+module_param_string(file_path, test_file_path, sizeof(test_file_path), 0400);
+MODULE_PARM_DESC(file_path, "file path to test");
+
+static bool test_lock_inode;
+module_param_named(lock_inode, test_lock_inode, bool, 0400);
+MODULE_PARM_DESC(lock_inode, "lock file -> inode -> i_rwsem");
+
+static bool test_lock_mapping;
+module_param_named(lock_mapping, test_lock_mapping, bool, 0400);
+MODULE_PARM_DESC(lock_mapping, "lock file -> mapping -> i_mmap_rwsem");
+
+static bool test_lock_sb_umount;
+module_param_named(lock_sb_umount, test_lock_sb_umount, bool, 0400);
+MODULE_PARM_DESC(lock_sb_umount, "lock file -> sb -> s_umount");
+
+static atomic_t alloc_pages_failed = ATOMIC_INIT(0);
+
+static atomic64_t max_lock_wait = ATOMIC64_INIT(0);
+
+static struct task_struct *main_task;
+static int master_cpu;
+
+static void test_lock(bool master, bool verbose)
+{
+ u64 wait_start;
+
+ if (measure_lock_wait)
+ wait_start = local_clock();
+
+ if (lock_mutex_ptr && master) {
+ if (verbose)
+ pr_notice("lock mutex %ps\n", (void *)lock_mutex_ptr);
+ mutex_lock((struct mutex *)lock_mutex_ptr);
+ }
+
+ if (lock_rwsem_ptr && master) {
+ if (verbose)
+ pr_notice("lock rw_semaphore %ps\n",
+ (void *)lock_rwsem_ptr);
+ if (lock_read)
+ down_read((struct rw_semaphore *)lock_rwsem_ptr);
+ else
+ down_write((struct rw_semaphore *)lock_rwsem_ptr);
+ }
+
+ if (lock_mmap_sem && master) {
+ if (verbose)
+ pr_notice("lock mmap_lock pid=%d\n", main_task->pid);
+ if (lock_read)
+ mmap_read_lock(main_task->mm);
+ else
+ mmap_write_lock(main_task->mm);
+ }
+
+ if (test_disable_irq)
+ local_irq_disable();
+
+ if (disable_softirq)
+ local_bh_disable();
+
+ if (disable_preempt)
+ preempt_disable();
+
+ if (lock_rcu)
+ rcu_read_lock();
+
+ if (lock_spinlock_ptr && master) {
+ if (verbose)
+ pr_notice("lock spinlock %ps\n",
+ (void *)lock_spinlock_ptr);
+ spin_lock((spinlock_t *)lock_spinlock_ptr);
+ }
+
+ if (lock_rwlock_ptr && master) {
+ if (verbose)
+ pr_notice("lock rwlock %ps\n",
+ (void *)lock_rwlock_ptr);
+ if (lock_read)
+ read_lock((rwlock_t *)lock_rwlock_ptr);
+ else
+ write_lock((rwlock_t *)lock_rwlock_ptr);
+ }
+
+ if (measure_lock_wait) {
+ s64 cur_wait = local_clock() - wait_start;
+ s64 max_wait = atomic64_read(&max_lock_wait);
+
+ do {
+ if (cur_wait < max_wait)
+ break;
+ max_wait = atomic64_cmpxchg(&max_lock_wait,
+ max_wait, cur_wait);
+ } while (max_wait != cur_wait);
+
+ if (cur_wait > lock_wait_threshold)
+ pr_notice_ratelimited("lock wait %lld ns\n", cur_wait);
+ }
+}
+
+static void test_unlock(bool master, bool verbose)
+{
+ if (lock_rwlock_ptr && master) {
+ if (lock_read)
+ read_unlock((rwlock_t *)lock_rwlock_ptr);
+ else
+ write_unlock((rwlock_t *)lock_rwlock_ptr);
+ if (verbose)
+ pr_notice("unlock rwlock %ps\n",
+ (void *)lock_rwlock_ptr);
+ }
+
+ if (lock_spinlock_ptr && master) {
+ spin_unlock((spinlock_t *)lock_spinlock_ptr);
+ if (verbose)
+ pr_notice("unlock spinlock %ps\n",
+ (void *)lock_spinlock_ptr);
+ }
+
+ if (lock_rcu)
+ rcu_read_unlock();
+
+ if (disable_preempt)
+ preempt_enable();
+
+ if (disable_softirq)
+ local_bh_enable();
+
+ if (test_disable_irq)
+ local_irq_enable();
+
+ if (lock_mmap_sem && master) {
+ if (lock_read)
+ mmap_read_unlock(main_task->mm);
+ else
+ mmap_write_unlock(main_task->mm);
+ if (verbose)
+ pr_notice("unlock mmap_lock pid=%d\n", main_task->pid);
+ }
+
+ if (lock_rwsem_ptr && master) {
+ if (lock_read)
+ up_read((struct rw_semaphore *)lock_rwsem_ptr);
+ else
+ up_write((struct rw_semaphore *)lock_rwsem_ptr);
+ if (verbose)
+ pr_notice("unlock rw_semaphore %ps\n",
+ (void *)lock_rwsem_ptr);
+ }
+
+ if (lock_mutex_ptr && master) {
+ mutex_unlock((struct mutex *)lock_mutex_ptr);
+ if (verbose)
+ pr_notice("unlock mutex %ps\n",
+ (void *)lock_mutex_ptr);
+ }
+}
+
+static void test_alloc_pages(struct list_head *pages)
+{
+ struct page *page;
+ unsigned int i;
+
+ for (i = 0; i < alloc_pages_nr; i++) {
+ page = alloc_pages(alloc_pages_gfp, alloc_pages_order);
+ if (!page) {
+ atomic_inc(&alloc_pages_failed);
+ break;
+ }
+ list_add(&page->lru, pages);
+ }
+}
+
+static void test_free_pages(struct list_head *pages)
+{
+ struct page *page, *next;
+
+ list_for_each_entry_safe(page, next, pages, lru)
+ __free_pages(page, alloc_pages_order);
+ INIT_LIST_HEAD(pages);
+}
+
+static void test_wait(unsigned int secs, unsigned int nsecs)
+{
+ if (wait_state == TASK_RUNNING) {
+ if (secs)
+ mdelay(secs * MSEC_PER_SEC);
+ if (nsecs)
+ ndelay(nsecs);
+ return;
+ }
+
+ __set_current_state(wait_state);
+ if (use_hrtimer) {
+ ktime_t time;
+
+ time = ns_to_ktime((u64)secs * NSEC_PER_SEC + nsecs);
+ schedule_hrtimeout(&time, HRTIMER_MODE_REL);
+ } else {
+ schedule_timeout(secs * HZ + nsecs_to_jiffies(nsecs));
+ }
+}
+
+static void test_lockup(bool master)
+{
+ u64 lockup_start = local_clock();
+ unsigned int iter = 0;
+ LIST_HEAD(pages);
+
+ pr_notice("Start on CPU%d\n", raw_smp_processor_id());
+
+ test_lock(master, true);
+
+ test_alloc_pages(&pages);
+
+ while (iter++ < iterations && !signal_pending(main_task)) {
+
+ if (iowait)
+ current->in_iowait = 1;
+
+ test_wait(time_secs, time_nsecs);
+
+ if (iowait)
+ current->in_iowait = 0;
+
+ if (reallocate_pages)
+ test_free_pages(&pages);
+
+ if (reacquire_locks)
+ test_unlock(master, false);
+
+ if (touch_softlockup)
+ touch_softlockup_watchdog();
+
+ if (touch_hardlockup)
+ touch_nmi_watchdog();
+
+ if (call_cond_resched)
+ cond_resched();
+
+ test_wait(cooldown_secs, cooldown_nsecs);
+
+ if (reacquire_locks)
+ test_lock(master, false);
+
+ if (reallocate_pages)
+ test_alloc_pages(&pages);
+ }
+
+ pr_notice("Finish on CPU%d in %lld ns\n", raw_smp_processor_id(),
+ local_clock() - lockup_start);
+
+ test_free_pages(&pages);
+
+ test_unlock(master, true);
+}
+
+static DEFINE_PER_CPU(struct work_struct, test_works);
+
+static void test_work_fn(struct work_struct *work)
+{
+ test_lockup(!lock_single ||
+ work == per_cpu_ptr(&test_works, master_cpu));
+}
+
+static bool test_kernel_ptr(unsigned long addr, int size)
+{
+ void *ptr = (void *)addr;
+ char buf;
+
+ if (!addr)
+ return false;
+
+ /* should be at least readable kernel address */
+ if (!IS_ENABLED(CONFIG_ALTERNATE_USER_ADDRESS_SPACE) &&
+ (access_ok((void __user *)ptr, 1) ||
+ access_ok((void __user *)ptr + size - 1, 1))) {
+ pr_err("user space ptr invalid in kernel: %#lx\n", addr);
+ return true;
+ }
+
+ if (get_kernel_nofault(buf, ptr) ||
+ get_kernel_nofault(buf, ptr + size - 1)) {
+ pr_err("invalid kernel ptr: %#lx\n", addr);
+ return true;
+ }
+
+ return false;
+}
+
+static bool __maybe_unused test_magic(unsigned long addr, int offset,
+ unsigned int expected)
+{
+ void *ptr = (void *)addr + offset;
+ unsigned int magic = 0;
+
+ if (!addr)
+ return false;
+
+ if (get_kernel_nofault(magic, ptr) || magic != expected) {
+ pr_err("invalid magic at %#lx + %#x = %#x, expected %#x\n",
+ addr, offset, magic, expected);
+ return true;
+ }
+
+ return false;
+}
+
+static int __init test_lockup_init(void)
+{
+ u64 test_start = local_clock();
+
+ main_task = current;
+
+ switch (state[0]) {
+ case 'S':
+ wait_state = TASK_INTERRUPTIBLE;
+ break;
+ case 'D':
+ wait_state = TASK_UNINTERRUPTIBLE;
+ break;
+ case 'K':
+ wait_state = TASK_KILLABLE;
+ break;
+ case 'R':
+ wait_state = TASK_RUNNING;
+ break;
+ default:
+ pr_err("unknown state=%s\n", state);
+ return -EINVAL;
+ }
+
+ if (alloc_pages_atomic)
+ alloc_pages_gfp = GFP_ATOMIC;
+
+ if (test_kernel_ptr(lock_spinlock_ptr, sizeof(spinlock_t)) ||
+ test_kernel_ptr(lock_rwlock_ptr, sizeof(rwlock_t)) ||
+ test_kernel_ptr(lock_mutex_ptr, sizeof(struct mutex)) ||
+ test_kernel_ptr(lock_rwsem_ptr, sizeof(struct rw_semaphore)))
+ return -EINVAL;
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+#ifdef CONFIG_PREEMPT_RT
+ if (test_magic(lock_spinlock_ptr,
+ offsetof(spinlock_t, lock.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwlock_ptr,
+ offsetof(rwlock_t, rwbase.rtmutex.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_mutex_ptr,
+ offsetof(struct mutex, rtmutex.wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwsem_ptr,
+ offsetof(struct rw_semaphore, rwbase.rtmutex.wait_lock.magic),
+ SPINLOCK_MAGIC))
+ return -EINVAL;
+#else
+ if (test_magic(lock_spinlock_ptr,
+ offsetof(spinlock_t, rlock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwlock_ptr,
+ offsetof(rwlock_t, magic),
+ RWLOCK_MAGIC) ||
+ test_magic(lock_mutex_ptr,
+ offsetof(struct mutex, wait_lock.magic),
+ SPINLOCK_MAGIC) ||
+ test_magic(lock_rwsem_ptr,
+ offsetof(struct rw_semaphore, wait_lock.magic),
+ SPINLOCK_MAGIC))
+ return -EINVAL;
+#endif
+#endif
+
+ if ((wait_state != TASK_RUNNING ||
+ (call_cond_resched && !reacquire_locks) ||
+ (alloc_pages_nr && gfpflags_allow_blocking(alloc_pages_gfp))) &&
+ (test_disable_irq || disable_softirq || disable_preempt ||
+ lock_rcu || lock_spinlock_ptr || lock_rwlock_ptr)) {
+ pr_err("refuse to sleep in atomic context\n");
+ return -EINVAL;
+ }
+
+ if (lock_mmap_sem && !main_task->mm) {
+ pr_err("no mm to lock mmap_lock\n");
+ return -EINVAL;
+ }
+
+ if (test_file_path[0]) {
+ test_file = filp_open(test_file_path, O_RDONLY, 0);
+ if (IS_ERR(test_file)) {
+ pr_err("failed to open %s: %ld\n", test_file_path, PTR_ERR(test_file));
+ return PTR_ERR(test_file);
+ }
+ test_inode = file_inode(test_file);
+ } else if (test_lock_inode ||
+ test_lock_mapping ||
+ test_lock_sb_umount) {
+ pr_err("no file to lock\n");
+ return -EINVAL;
+ }
+
+ if (test_lock_inode && test_inode)
+ lock_rwsem_ptr = (unsigned long)&test_inode->i_rwsem;
+
+ if (test_lock_mapping && test_file && test_file->f_mapping)
+ lock_rwsem_ptr = (unsigned long)&test_file->f_mapping->i_mmap_rwsem;
+
+ if (test_lock_sb_umount && test_inode)
+ lock_rwsem_ptr = (unsigned long)&test_inode->i_sb->s_umount;
+
+ pr_notice("START pid=%d time=%u +%u ns cooldown=%u +%u ns iterations=%u state=%s %s%s%s%s%s%s%s%s%s%s%s\n",
+ main_task->pid, time_secs, time_nsecs,
+ cooldown_secs, cooldown_nsecs, iterations, state,
+ all_cpus ? "all_cpus " : "",
+ iowait ? "iowait " : "",
+ test_disable_irq ? "disable_irq " : "",
+ disable_softirq ? "disable_softirq " : "",
+ disable_preempt ? "disable_preempt " : "",
+ lock_rcu ? "lock_rcu " : "",
+ lock_read ? "lock_read " : "",
+ touch_softlockup ? "touch_softlockup " : "",
+ touch_hardlockup ? "touch_hardlockup " : "",
+ call_cond_resched ? "call_cond_resched " : "",
+ reacquire_locks ? "reacquire_locks " : "");
+
+ if (alloc_pages_nr)
+ pr_notice("ALLOCATE PAGES nr=%u order=%u gfp=%pGg %s\n",
+ alloc_pages_nr, alloc_pages_order, &alloc_pages_gfp,
+ reallocate_pages ? "reallocate_pages " : "");
+
+ if (all_cpus) {
+ unsigned int cpu;
+
+ cpus_read_lock();
+
+ preempt_disable();
+ master_cpu = smp_processor_id();
+ for_each_online_cpu(cpu) {
+ INIT_WORK(per_cpu_ptr(&test_works, cpu), test_work_fn);
+ queue_work_on(cpu, system_highpri_wq,
+ per_cpu_ptr(&test_works, cpu));
+ }
+ preempt_enable();
+
+ for_each_online_cpu(cpu)
+ flush_work(per_cpu_ptr(&test_works, cpu));
+
+ cpus_read_unlock();
+ } else {
+ test_lockup(true);
+ }
+
+ if (measure_lock_wait)
+ pr_notice("Maximum lock wait: %lld ns\n",
+ atomic64_read(&max_lock_wait));
+
+ if (alloc_pages_nr)
+ pr_notice("Page allocation failed %u times\n",
+ atomic_read(&alloc_pages_failed));
+
+ pr_notice("FINISH in %llu ns\n", local_clock() - test_start);
+
+ if (test_file)
+ fput(test_file);
+
+ if (signal_pending(main_task))
+ return -EINTR;
+
+ return -EAGAIN;
+}
+module_init(test_lockup_init);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Konstantin Khlebnikov <khlebnikov@yandex-team.ru>");
+MODULE_DESCRIPTION("Test module to generate lockups");