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().
  ...

15 files changed, 856 insertions, 0 deletions

diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/assume.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/assume.h
new file mode 100644
index 000000000..570a49d9d
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/assume.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASSUME_H
+#define ASSUME_H
+
+/* Provide an assumption macro that can be disabled for gcc. */
+#ifdef RUN
+#define assume(x) \
+	do { \
+		/* Evaluate x to suppress warnings. */ \
+		(void) (x); \
+	} while (0)
+
+#else
+#define assume(x) __CPROVER_assume(x)
+#endif
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h
new file mode 100644
index 000000000..3f95a768a
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/barriers.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef BARRIERS_H
+#define BARRIERS_H
+
+#define barrier() __asm__ __volatile__("" : : : "memory")
+
+#ifdef RUN
+#define smp_mb() __sync_synchronize()
+#define smp_mb__after_unlock_lock() __sync_synchronize()
+#else
+/*
+ * Copied from CBMC's implementation of __sync_synchronize(), which
+ * seems to be disabled by default.
+ */
+#define smp_mb() __CPROVER_fence("WWfence", "RRfence", "RWfence", "WRfence", \
+				 "WWcumul", "RRcumul", "RWcumul", "WRcumul")
+#define smp_mb__after_unlock_lock() __CPROVER_fence("WWfence", "RRfence", "RWfence", "WRfence", \
+				    "WWcumul", "RRcumul", "RWcumul", "WRcumul")
+#endif
+
+/*
+ * Allow memory barriers to be disabled in either the read or write side
+ * of SRCU individually.
+ */
+
+#ifndef NO_SYNC_SMP_MB
+#define sync_smp_mb() smp_mb()
+#else
+#define sync_smp_mb() do {} while (0)
+#endif
+
+#ifndef NO_READ_SIDE_SMP_MB
+#define rs_smp_mb() smp_mb()
+#else
+#define rs_smp_mb() do {} while (0)
+#endif
+
+#define READ_ONCE(x) (*(volatile typeof(x) *) &(x))
+#define WRITE_ONCE(x) ((*(volatile typeof(x) *) &(x)) = (val))
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/bug_on.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/bug_on.h
new file mode 100644
index 000000000..5e7912c6a
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/bug_on.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef BUG_ON_H
+#define BUG_ON_H
+
+#include <assert.h>
+
+#define BUG() assert(0)
+#define BUG_ON(x) assert(!(x))
+
+/* Does it make sense to treat warnings as errors? */
+#define WARN() BUG()
+#define WARN_ON(x) (BUG_ON(x), false)
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/combined_source.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/combined_source.c
new file mode 100644
index 000000000..e67ee5b3d
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/combined_source.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <config.h>
+
+/* Include all source files. */
+
+#include "include_srcu.c"
+
+#include "preempt.c"
+#include "misc.c"
+
+/* Used by test.c files */
+#include <pthread.h>
+#include <stdlib.h>
+#include <linux/srcu.h>
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/config.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/config.h
new file mode 100644
index 000000000..283d71033
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/config.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* "Cheater" definitions based on restricted Kconfig choices. */
+
+#undef CONFIG_TINY_RCU
+#undef __CHECKER__
+#undef CONFIG_DEBUG_LOCK_ALLOC
+#undef CONFIG_DEBUG_OBJECTS_RCU_HEAD
+#undef CONFIG_HOTPLUG_CPU
+#undef CONFIG_MODULES
+#undef CONFIG_NO_HZ_FULL_SYSIDLE
+#undef CONFIG_PREEMPT_COUNT
+#undef CONFIG_PREEMPT_RCU
+#undef CONFIG_PROVE_RCU
+#undef CONFIG_RCU_NOCB_CPU
+#undef CONFIG_RCU_NOCB_CPU_ALL
+#undef CONFIG_RCU_STALL_COMMON
+#undef CONFIG_RCU_TRACE
+#undef CONFIG_RCU_USER_QS
+#undef CONFIG_TASKS_RCU
+#define CONFIG_TREE_RCU
+
+#define CONFIG_GENERIC_ATOMIC64
+
+#if NR_CPUS > 1
+#define CONFIG_SMP
+#else
+#undef CONFIG_SMP
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/include_srcu.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/include_srcu.c
new file mode 100644
index 000000000..e5202d4cf
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/include_srcu.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <config.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "int_typedefs.h"
+
+#include "barriers.h"
+#include "bug_on.h"
+#include "locks.h"
+#include "misc.h"
+#include "preempt.h"
+#include "percpu.h"
+#include "workqueues.h"
+
+#ifdef USE_SIMPLE_SYNC_SRCU
+#define synchronize_srcu(sp) synchronize_srcu_original(sp)
+#endif
+
+#include <srcu.c>
+
+#ifdef USE_SIMPLE_SYNC_SRCU
+#undef synchronize_srcu
+
+#include "simple_sync_srcu.c"
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/int_typedefs.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/int_typedefs.h
new file mode 100644
index 000000000..0dd27aa51
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/int_typedefs.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef INT_TYPEDEFS_H
+#define INT_TYPEDEFS_H
+
+#include <inttypes.h>
+
+typedef int8_t s8;
+typedef uint8_t u8;
+typedef int16_t s16;
+typedef uint16_t u16;
+typedef int32_t s32;
+typedef uint32_t u32;
+typedef int64_t s64;
+typedef uint64_t u64;
+
+typedef int8_t __s8;
+typedef uint8_t __u8;
+typedef int16_t __s16;
+typedef uint16_t __u16;
+typedef int32_t __s32;
+typedef uint32_t __u32;
+typedef int64_t __s64;
+typedef uint64_t __u64;
+
+#define S8_C(x) INT8_C(x)
+#define U8_C(x) UINT8_C(x)
+#define S16_C(x) INT16_C(x)
+#define U16_C(x) UINT16_C(x)
+#define S32_C(x) INT32_C(x)
+#define U32_C(x) UINT32_C(x)
+#define S64_C(x) INT64_C(x)
+#define U64_C(x) UINT64_C(x)
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/locks.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/locks.h
new file mode 100644
index 000000000..1e24827f9
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/locks.h
@@ -0,0 +1,221 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef LOCKS_H
+#define LOCKS_H
+
+#include <limits.h>
+#include <pthread.h>
+#include <stdbool.h>
+
+#include "assume.h"
+#include "bug_on.h"
+#include "preempt.h"
+
+int nondet_int(void);
+
+#define __acquire(x)
+#define __acquires(x)
+#define __release(x)
+#define __releases(x)
+
+/* Only use one lock mechanism. Select which one. */
+#ifdef PTHREAD_LOCK
+struct lock_impl {
+	pthread_mutex_t mutex;
+};
+
+static inline void lock_impl_lock(struct lock_impl *lock)
+{
+	BUG_ON(pthread_mutex_lock(&lock->mutex));
+}
+
+static inline void lock_impl_unlock(struct lock_impl *lock)
+{
+	BUG_ON(pthread_mutex_unlock(&lock->mutex));
+}
+
+static inline bool lock_impl_trylock(struct lock_impl *lock)
+{
+	int err = pthread_mutex_trylock(&lock->mutex);
+
+	if (!err)
+		return true;
+	else if (err == EBUSY)
+		return false;
+	BUG();
+}
+
+static inline void lock_impl_init(struct lock_impl *lock)
+{
+	pthread_mutex_init(&lock->mutex, NULL);
+}
+
+#define LOCK_IMPL_INITIALIZER {.mutex = PTHREAD_MUTEX_INITIALIZER}
+
+#else /* !defined(PTHREAD_LOCK) */
+/* Spinlock that assumes that it always gets the lock immediately. */
+
+struct lock_impl {
+	bool locked;
+};
+
+static inline bool lock_impl_trylock(struct lock_impl *lock)
+{
+#ifdef RUN
+	/* TODO: Should this be a test and set? */
+	return __sync_bool_compare_and_swap(&lock->locked, false, true);
+#else
+	__CPROVER_atomic_begin();
+	bool old_locked = lock->locked;
+	lock->locked = true;
+	__CPROVER_atomic_end();
+
+	/* Minimal barrier to prevent accesses leaking out of lock. */
+	__CPROVER_fence("RRfence", "RWfence");
+
+	return !old_locked;
+#endif
+}
+
+static inline void lock_impl_lock(struct lock_impl *lock)
+{
+	/*
+	 * CBMC doesn't support busy waiting, so just assume that the
+	 * lock is available.
+	 */
+	assume(lock_impl_trylock(lock));
+
+	/*
+	 * If the lock was already held by this thread then the assumption
+	 * is unsatisfiable (deadlock).
+	 */
+}
+
+static inline void lock_impl_unlock(struct lock_impl *lock)
+{
+#ifdef RUN
+	BUG_ON(!__sync_bool_compare_and_swap(&lock->locked, true, false));
+#else
+	/* Minimal barrier to prevent accesses leaking out of lock. */
+	__CPROVER_fence("RWfence", "WWfence");
+
+	__CPROVER_atomic_begin();
+	bool old_locked = lock->locked;
+	lock->locked = false;
+	__CPROVER_atomic_end();
+
+	BUG_ON(!old_locked);
+#endif
+}
+
+static inline void lock_impl_init(struct lock_impl *lock)
+{
+	lock->locked = false;
+}
+
+#define LOCK_IMPL_INITIALIZER {.locked = false}
+
+#endif /* !defined(PTHREAD_LOCK) */
+
+/*
+ * Implement spinlocks using the lock mechanism. Wrap the lock to prevent mixing
+ * locks of different types.
+ */
+typedef struct {
+	struct lock_impl internal_lock;
+} spinlock_t;
+
+#define SPIN_LOCK_UNLOCKED {.internal_lock = LOCK_IMPL_INITIALIZER}
+#define __SPIN_LOCK_UNLOCKED(x) SPIN_LOCK_UNLOCKED
+#define DEFINE_SPINLOCK(x) spinlock_t x = SPIN_LOCK_UNLOCKED
+
+static inline void spin_lock_init(spinlock_t *lock)
+{
+	lock_impl_init(&lock->internal_lock);
+}
+
+static inline void spin_lock(spinlock_t *lock)
+{
+	/*
+	 * Spin locks also need to be removed in order to eliminate all
+	 * memory barriers. They are only used by the write side anyway.
+	 */
+#ifndef NO_SYNC_SMP_MB
+	preempt_disable();
+	lock_impl_lock(&lock->internal_lock);
+#endif
+}
+
+static inline void spin_unlock(spinlock_t *lock)
+{
+#ifndef NO_SYNC_SMP_MB
+	lock_impl_unlock(&lock->internal_lock);
+	preempt_enable();
+#endif
+}
+
+/* Don't bother with interrupts */
+#define spin_lock_irq(lock) spin_lock(lock)
+#define spin_unlock_irq(lock) spin_unlock(lock)
+#define spin_lock_irqsave(lock, flags) spin_lock(lock)
+#define spin_unlock_irqrestore(lock, flags) spin_unlock(lock)
+
+/*
+ * This is supposed to return an int, but I think that a bool should work as
+ * well.
+ */
+static inline bool spin_trylock(spinlock_t *lock)
+{
+#ifndef NO_SYNC_SMP_MB
+	preempt_disable();
+	return lock_impl_trylock(&lock->internal_lock);
+#else
+	return true;
+#endif
+}
+
+struct completion {
+	/* Hopefully this won't overflow. */
+	unsigned int count;
+};
+
+#define COMPLETION_INITIALIZER(x) {.count = 0}
+#define DECLARE_COMPLETION(x) struct completion x = COMPLETION_INITIALIZER(x)
+#define DECLARE_COMPLETION_ONSTACK(x) DECLARE_COMPLETION(x)
+
+static inline void init_completion(struct completion *c)
+{
+	c->count = 0;
+}
+
+static inline void wait_for_completion(struct completion *c)
+{
+	unsigned int prev_count = __sync_fetch_and_sub(&c->count, 1);
+
+	assume(prev_count);
+}
+
+static inline void complete(struct completion *c)
+{
+	unsigned int prev_count = __sync_fetch_and_add(&c->count, 1);
+
+	BUG_ON(prev_count == UINT_MAX);
+}
+
+/* This function probably isn't very useful for CBMC. */
+static inline bool try_wait_for_completion(struct completion *c)
+{
+	BUG();
+}
+
+static inline bool completion_done(struct completion *c)
+{
+	return c->count;
+}
+
+/* TODO: Implement complete_all */
+static inline void complete_all(struct completion *c)
+{
+	BUG();
+}
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.c
new file mode 100644
index 000000000..9440cc39e
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <config.h>
+
+#include "misc.h"
+#include "bug_on.h"
+
+struct rcu_head;
+
+void wakeme_after_rcu(struct rcu_head *head)
+{
+	BUG();
+}
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.h
new file mode 100644
index 000000000..aca50030f
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/misc.h
@@ -0,0 +1,58 @@
+#ifndef MISC_H
+#define MISC_H
+
+#include "assume.h"
+#include "int_typedefs.h"
+#include "locks.h"
+
+#include <linux/types.h>
+
+/* Probably won't need to deal with bottom halves. */
+static inline void local_bh_disable(void) {}
+static inline void local_bh_enable(void) {}
+
+#define MODULE_ALIAS(X)
+#define module_param(...)
+#define EXPORT_SYMBOL_GPL(x)
+
+#define container_of(ptr, type, member) ({			\
+	const typeof(((type *)0)->member) *__mptr = (ptr);	\
+	(type *)((char *)__mptr - offsetof(type, member));	\
+})
+
+#ifndef USE_SIMPLE_SYNC_SRCU
+/* Abuse udelay to make sure that busy loops terminate. */
+#define udelay(x) assume(0)
+
+#else
+
+/* The simple custom synchronize_srcu is ok with try_check_zero failing. */
+#define udelay(x) do { } while (0)
+#endif
+
+#define trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \
+	do { } while (0)
+
+#define notrace
+
+/* Avoid including rcupdate.h */
+struct rcu_synchronize {
+	struct rcu_head head;
+	struct completion completion;
+};
+
+void wakeme_after_rcu(struct rcu_head *head);
+
+#define rcu_lock_acquire(a) do { } while (0)
+#define rcu_lock_release(a) do { } while (0)
+#define rcu_lockdep_assert(c, s) do { } while (0)
+#define RCU_LOCKDEP_WARN(c, s) do { } while (0)
+
+/* Let CBMC non-deterministically choose switch between normal and expedited. */
+bool rcu_gp_is_normal(void);
+bool rcu_gp_is_expedited(void);
+
+/* Do the same for old versions of rcu. */
+#define rcu_expedited (rcu_gp_is_expedited())
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/percpu.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/percpu.h
new file mode 100644
index 000000000..27e67a3f2
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/percpu.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef PERCPU_H
+#define PERCPU_H
+
+#include <stddef.h>
+#include "bug_on.h"
+#include "preempt.h"
+
+#define __percpu
+
+/* Maximum size of any percpu data. */
+#define PERCPU_OFFSET (4 * sizeof(long))
+
+/* Ignore alignment, as CBMC doesn't care about false sharing. */
+#define alloc_percpu(type) __alloc_percpu(sizeof(type), 1)
+
+static inline void *__alloc_percpu(size_t size, size_t align)
+{
+	BUG();
+	return NULL;
+}
+
+static inline void free_percpu(void *ptr)
+{
+	BUG();
+}
+
+#define per_cpu_ptr(ptr, cpu) \
+	((typeof(ptr)) ((char *) (ptr) + PERCPU_OFFSET * cpu))
+
+#define __this_cpu_inc(pcp) __this_cpu_add(pcp, 1)
+#define __this_cpu_dec(pcp) __this_cpu_sub(pcp, 1)
+#define __this_cpu_sub(pcp, n) __this_cpu_add(pcp, -(typeof(pcp)) (n))
+
+#define this_cpu_inc(pcp) this_cpu_add(pcp, 1)
+#define this_cpu_dec(pcp) this_cpu_sub(pcp, 1)
+#define this_cpu_sub(pcp, n) this_cpu_add(pcp, -(typeof(pcp)) (n))
+
+/* Make CBMC use atomics to work around bug. */
+#ifdef RUN
+#define THIS_CPU_ADD_HELPER(ptr, x) (*(ptr) += (x))
+#else
+/*
+ * Split the atomic into a read and a write so that it has the least
+ * possible ordering.
+ */
+#define THIS_CPU_ADD_HELPER(ptr, x) \
+	do { \
+		typeof(ptr) this_cpu_add_helper_ptr = (ptr); \
+		typeof(ptr) this_cpu_add_helper_x = (x); \
+		typeof(*ptr) this_cpu_add_helper_temp; \
+		__CPROVER_atomic_begin(); \
+		this_cpu_add_helper_temp = *(this_cpu_add_helper_ptr); \
+		__CPROVER_atomic_end(); \
+		this_cpu_add_helper_temp += this_cpu_add_helper_x; \
+		__CPROVER_atomic_begin(); \
+		*(this_cpu_add_helper_ptr) = this_cpu_add_helper_temp; \
+		__CPROVER_atomic_end(); \
+	} while (0)
+#endif
+
+/*
+ * For some reason CBMC needs an atomic operation even though this is percpu
+ * data.
+ */
+#define __this_cpu_add(pcp, n) \
+	do { \
+		BUG_ON(preemptible()); \
+		THIS_CPU_ADD_HELPER(per_cpu_ptr(&(pcp), thread_cpu_id), \
+				    (typeof(pcp)) (n)); \
+	} while (0)
+
+#define this_cpu_add(pcp, n) \
+	do { \
+		int this_cpu_add_impl_cpu = get_cpu(); \
+		THIS_CPU_ADD_HELPER(per_cpu_ptr(&(pcp), this_cpu_add_impl_cpu), \
+				    (typeof(pcp)) (n)); \
+		put_cpu(); \
+	} while (0)
+
+/*
+ * This will cause a compiler warning because of the cast from char[][] to
+ * type*. This will cause a compile time error if type is too big.
+ */
+#define DEFINE_PER_CPU(type, name) \
+	char name[NR_CPUS][PERCPU_OFFSET]; \
+	typedef char percpu_too_big_##name \
+		[sizeof(type) > PERCPU_OFFSET ? -1 : 1]
+
+#define for_each_possible_cpu(cpu) \
+	for ((cpu) = 0; (cpu) < NR_CPUS; ++(cpu))
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c
new file mode 100644
index 000000000..b4083ae34
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <config.h>
+
+#include "preempt.h"
+
+#include "assume.h"
+#include "locks.h"
+
+/* Support NR_CPUS of at most 64 */
+#define CPU_PREEMPTION_LOCKS_INIT0 LOCK_IMPL_INITIALIZER
+#define CPU_PREEMPTION_LOCKS_INIT1 \
+	CPU_PREEMPTION_LOCKS_INIT0, CPU_PREEMPTION_LOCKS_INIT0
+#define CPU_PREEMPTION_LOCKS_INIT2 \
+	CPU_PREEMPTION_LOCKS_INIT1, CPU_PREEMPTION_LOCKS_INIT1
+#define CPU_PREEMPTION_LOCKS_INIT3 \
+	CPU_PREEMPTION_LOCKS_INIT2, CPU_PREEMPTION_LOCKS_INIT2
+#define CPU_PREEMPTION_LOCKS_INIT4 \
+	CPU_PREEMPTION_LOCKS_INIT3, CPU_PREEMPTION_LOCKS_INIT3
+#define CPU_PREEMPTION_LOCKS_INIT5 \
+	CPU_PREEMPTION_LOCKS_INIT4, CPU_PREEMPTION_LOCKS_INIT4
+
+/*
+ * Simulate disabling preemption by locking a particular cpu. NR_CPUS
+ * should be the actual number of cpus, not just the maximum.
+ */
+struct lock_impl cpu_preemption_locks[NR_CPUS] = {
+	CPU_PREEMPTION_LOCKS_INIT0
+#if (NR_CPUS - 1) & 1
+	, CPU_PREEMPTION_LOCKS_INIT0
+#endif
+#if (NR_CPUS - 1) & 2
+	, CPU_PREEMPTION_LOCKS_INIT1
+#endif
+#if (NR_CPUS - 1) & 4
+	, CPU_PREEMPTION_LOCKS_INIT2
+#endif
+#if (NR_CPUS - 1) & 8
+	, CPU_PREEMPTION_LOCKS_INIT3
+#endif
+#if (NR_CPUS - 1) & 16
+	, CPU_PREEMPTION_LOCKS_INIT4
+#endif
+#if (NR_CPUS - 1) & 32
+	, CPU_PREEMPTION_LOCKS_INIT5
+#endif
+};
+
+#undef CPU_PREEMPTION_LOCKS_INIT0
+#undef CPU_PREEMPTION_LOCKS_INIT1
+#undef CPU_PREEMPTION_LOCKS_INIT2
+#undef CPU_PREEMPTION_LOCKS_INIT3
+#undef CPU_PREEMPTION_LOCKS_INIT4
+#undef CPU_PREEMPTION_LOCKS_INIT5
+
+__thread int thread_cpu_id;
+__thread int preempt_disable_count;
+
+void preempt_disable(void)
+{
+	BUG_ON(preempt_disable_count < 0 || preempt_disable_count == INT_MAX);
+
+	if (preempt_disable_count++)
+		return;
+
+	thread_cpu_id = nondet_int();
+	assume(thread_cpu_id >= 0);
+	assume(thread_cpu_id < NR_CPUS);
+	lock_impl_lock(&cpu_preemption_locks[thread_cpu_id]);
+}
+
+void preempt_enable(void)
+{
+	BUG_ON(preempt_disable_count < 1);
+
+	if (--preempt_disable_count)
+		return;
+
+	lock_impl_unlock(&cpu_preemption_locks[thread_cpu_id]);
+}
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.h
new file mode 100644
index 000000000..f8b762cd2
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/preempt.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef PREEMPT_H
+#define PREEMPT_H
+
+#include <stdbool.h>
+
+#include "bug_on.h"
+
+/* This flag contains garbage if preempt_disable_count is 0. */
+extern __thread int thread_cpu_id;
+
+/* Support recursive preemption disabling. */
+extern __thread int preempt_disable_count;
+
+void preempt_disable(void);
+void preempt_enable(void);
+
+static inline void preempt_disable_notrace(void)
+{
+	preempt_disable();
+}
+
+static inline void preempt_enable_no_resched(void)
+{
+	preempt_enable();
+}
+
+static inline void preempt_enable_notrace(void)
+{
+	preempt_enable();
+}
+
+static inline int preempt_count(void)
+{
+	return preempt_disable_count;
+}
+
+static inline bool preemptible(void)
+{
+	return !preempt_count();
+}
+
+static inline int get_cpu(void)
+{
+	preempt_disable();
+	return thread_cpu_id;
+}
+
+static inline void put_cpu(void)
+{
+	preempt_enable();
+}
+
+static inline void might_sleep(void)
+{
+	BUG_ON(preempt_disable_count);
+}
+
+#endif
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/simple_sync_srcu.c b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/simple_sync_srcu.c
new file mode 100644
index 000000000..97f592048
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/simple_sync_srcu.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <config.h>
+
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stddef.h>
+#include <string.h>
+#include <sys/types.h>
+
+#include "int_typedefs.h"
+
+#include "barriers.h"
+#include "bug_on.h"
+#include "locks.h"
+#include "misc.h"
+#include "preempt.h"
+#include "percpu.h"
+#include "workqueues.h"
+
+#include <linux/srcu.h>
+
+/* Functions needed from modify_srcu.c */
+bool try_check_zero(struct srcu_struct *sp, int idx, int trycount);
+void srcu_flip(struct srcu_struct *sp);
+
+/* Simpler implementation of synchronize_srcu that ignores batching. */
+void synchronize_srcu(struct srcu_struct *sp)
+{
+	int idx;
+	/*
+	 * This code assumes that try_check_zero will succeed anyway,
+	 * so there is no point in multiple tries.
+	 */
+	const int trycount = 1;
+
+	might_sleep();
+
+	/* Ignore the lock, as multiple writers aren't working yet anyway. */
+
+	idx = 1 ^ (sp->completed & 1);
+
+	/* For comments see srcu_advance_batches. */
+
+	assume(try_check_zero(sp, idx, trycount));
+
+	srcu_flip(sp);
+
+	assume(try_check_zero(sp, idx^1, trycount));
+}
diff --git a/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/workqueues.h b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/workqueues.h
new file mode 100644
index 000000000..28b960300
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/formal/srcu-cbmc/src/workqueues.h
@@ -0,0 +1,103 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef WORKQUEUES_H
+#define WORKQUEUES_H
+
+#include <stdbool.h>
+
+#include "barriers.h"
+#include "bug_on.h"
+#include "int_typedefs.h"
+
+#include <linux/types.h>
+
+/* Stub workqueue implementation. */
+
+struct work_struct;
+typedef void (*work_func_t)(struct work_struct *work);
+void delayed_work_timer_fn(unsigned long __data);
+
+struct work_struct {
+/*	atomic_long_t data; */
+	unsigned long data;
+
+	struct list_head entry;
+	work_func_t func;
+#ifdef CONFIG_LOCKDEP
+	struct lockdep_map lockdep_map;
+#endif
+};
+
+struct timer_list {
+	struct hlist_node	entry;
+	unsigned long		expires;
+	void			(*function)(unsigned long);
+	unsigned long		data;
+	u32			flags;
+	int			slack;
+};
+
+struct delayed_work {
+	struct work_struct work;
+	struct timer_list timer;
+
+	/* target workqueue and CPU ->timer uses to queue ->work */
+	struct workqueue_struct *wq;
+	int cpu;
+};
+
+
+static inline bool schedule_work(struct work_struct *work)
+{
+	BUG();
+	return true;
+}
+
+static inline bool schedule_work_on(int cpu, struct work_struct *work)
+{
+	BUG();
+	return true;
+}
+
+static inline bool queue_work(struct workqueue_struct *wq,
+			      struct work_struct *work)
+{
+	BUG();
+	return true;
+}
+
+static inline bool queue_delayed_work(struct workqueue_struct *wq,
+				      struct delayed_work *dwork,
+				      unsigned long delay)
+{
+	BUG();
+	return true;
+}
+
+#define INIT_WORK(w, f) \
+	do { \
+		(w)->data = 0; \
+		(w)->func = (f); \
+	} while (0)
+
+#define INIT_DELAYED_WORK(w, f) INIT_WORK(&(w)->work, (f))
+
+#define __WORK_INITIALIZER(n, f) { \
+		.data = 0, \
+		.entry = { &(n).entry, &(n).entry }, \
+		.func = f \
+	}
+
+/* Don't bother initializing timer. */
+#define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \
+	.work = __WORK_INITIALIZER((n).work, (f)), \
+	}
+
+#define DECLARE_WORK(n, f) \
+	struct workqueue_struct n = __WORK_INITIALIZER
+
+#define DECLARE_DELAYED_WORK(n, f) \
+	struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0)
+
+#define system_power_efficient_wq ((struct workqueue_struct *) NULL)
+
+#endif