Merge branch 'linus' into locking/core, to resolve conflicts

Conflicts:
	include/linux/compiler-clang.h
	include/linux/compiler-gcc.h
	include/linux/compiler-intel.h
	include/uapi/linux/stddef.h

Signed-off-by: Ingo Molnar <mingo@kernel.org>

139 files changed, 219 insertions, 42 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index ed470aac53da..172d151d429c 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 #
 # Makefile for the linux kernel.
 #
diff --git a/kernel/acct.c b/kernel/acct.c
index 21eedd0dd81a..d15c0ee4d955 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  linux/kernel/acct.c
  *
diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index 011d46e5f73f..d4b050d9a66e 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "audit.h"
 #include <linux/fsnotify_backend.h>
 #include <linux/namei.h>
diff --git a/kernel/bounds.c b/kernel/bounds.c
index e1d1d1952bfa..c373e887c066 100644
--- a/kernel/bounds.c
+++ b/kernel/bounds.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Generate definitions needed by the preprocessor.
  * This code generates raw asm output which is post-processed
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index 897daa005b23..af3ab6164ff5 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y := core.o
 
 obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o tnum.o
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c
index 2b6eb35ae5d3..dbd7b322a86b 100644
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -93,13 +93,27 @@ static inline struct smap_psock *smap_psock_sk(const struct sock *sk)
         return rcu_dereference_sk_user_data(sk);
 }
 
+/* compute the linear packet data range [data, data_end) for skb when
+ * sk_skb type programs are in use.
+ */
+static inline void bpf_compute_data_end_sk_skb(struct sk_buff *skb)
+{
+        TCP_SKB_CB(skb)->bpf.data_end = skb->data + skb_headlen(skb);
+}
+
+enum __sk_action {
+        __SK_DROP = 0,
+        __SK_PASS,
+        __SK_REDIRECT,
+};
+
 static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb)
 {
         struct bpf_prog *prog = READ_ONCE(psock->bpf_verdict);
         int rc;
 
         if (unlikely(!prog))
-                return SK_DROP;
+                return __SK_DROP;
 
         skb_orphan(skb);
         /* We need to ensure that BPF metadata for maps is also cleared
@@ -108,13 +122,16 @@ static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb)
          */
         TCP_SKB_CB(skb)->bpf.map = NULL;
         skb->sk = psock->sock;
-        bpf_compute_data_end(skb);
+        bpf_compute_data_end_sk_skb(skb);
         preempt_disable();
         rc = (*prog->bpf_func)(skb, prog->insnsi);
         preempt_enable();
         skb->sk = NULL;
 
-        return rc;
+        /* Moving return codes from UAPI namespace into internal namespace */
+        return rc == SK_PASS ?
+                (TCP_SKB_CB(skb)->bpf.map ? __SK_REDIRECT : __SK_PASS) :
+                __SK_DROP;
 }
 
 static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
@@ -124,7 +141,7 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
 
         rc = smap_verdict_func(psock, skb);
         switch (rc) {
-        case SK_REDIRECT:
+        case __SK_REDIRECT:
                 sk = do_sk_redirect_map(skb);
                 if (likely(sk)) {
                         struct smap_psock *peer = smap_psock_sk(sk);
@@ -140,7 +157,7 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
                         }
                 }
         /* Fall through and free skb otherwise */
-        case SK_DROP:
+        case __SK_DROP:
         default:
                 kfree_skb(skb);
         }
@@ -368,7 +385,7 @@ static int smap_parse_func_strparser(struct strparser *strp,
          * any socket yet.
          */
         skb->sk = psock->sock;
-        bpf_compute_data_end(skb);
+        bpf_compute_data_end_sk_skb(skb);
         rc = (*prog->bpf_func)(skb, prog->insnsi);
         skb->sk = NULL;
         rcu_read_unlock();
diff --git a/kernel/capability.c b/kernel/capability.c
index f97fe77ceb88..1e1c0236f55b 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/capability.c
  *
diff --git a/kernel/cgroup/Makefile b/kernel/cgroup/Makefile
index ce693ccb8c58..ae448f7632cc 100644
--- a/kernel/cgroup/Makefile
+++ b/kernel/cgroup/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y := cgroup.o namespace.o cgroup-v1.o
 
 obj-$(CONFIG_CGROUP_FREEZER) += freezer.o
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 5151ff256c29..bf54ade001be 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __CGROUP_INTERNAL_H
 #define __CGROUP_INTERNAL_H
 
diff --git a/kernel/cgroup/debug.c b/kernel/cgroup/debug.c
index f661b4cc5efd..5f780d8f6a9d 100644
--- a/kernel/cgroup/debug.c
+++ b/kernel/cgroup/debug.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Debug controller
  *
diff --git a/kernel/cgroup/namespace.c b/kernel/cgroup/namespace.c
index 66129eb4371d..b05f1dd58a62 100644
--- a/kernel/cgroup/namespace.c
+++ b/kernel/cgroup/namespace.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "cgroup-internal.h"
 
 #include <linux/sched/task.h>
diff --git a/kernel/dma.c b/kernel/dma.c
index 6c6262f86c17..3506fc34a712 100644
--- a/kernel/dma.c
+++ b/kernel/dma.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/dma.c: A DMA channel allocator. Inspired by linux/kernel/irq.c.
  *
diff --git a/kernel/elfcore.c b/kernel/elfcore.c
index e556751d15d9..fc482c8e0bd8 100644
--- a/kernel/elfcore.c
+++ b/kernel/elfcore.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/elf.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
diff --git a/kernel/events/Makefile b/kernel/events/Makefile
index 2925188f50ea..3c022e33c109 100644
--- a/kernel/events/Makefile
+++ b/kernel/events/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_core.o = $(CC_FLAGS_FTRACE)
 endif
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 8fd2f2d1358a..b315aebbcc3f 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -901,9 +901,11 @@ list_update_cgroup_event(struct perf_event *event,
         cpuctx_entry = &cpuctx->cgrp_cpuctx_entry;
         /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/
         if (add) {
+                struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx);
+
                 list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list));
-                if (perf_cgroup_from_task(current, ctx) == event->cgrp)
-                        cpuctx->cgrp = event->cgrp;
+                if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup))
+                        cpuctx->cgrp = cgrp;
         } else {
                 list_del(cpuctx_entry);
                 cpuctx->cgrp = NULL;
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index 843e97047335..09b1537ae06c 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _KERNEL_EVENTS_INTERNAL_H
 #define _KERNEL_EVENTS_INTERNAL_H
 
diff --git a/kernel/exec_domain.c b/kernel/exec_domain.c
index 6873bb3e6b7e..0975b0268545 100644
--- a/kernel/exec_domain.c
+++ b/kernel/exec_domain.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Handling of different ABIs (personalities).
  *
diff --git a/kernel/futex.c b/kernel/futex.c
index 0518a0bfc746..76ed5921117a 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -903,11 +903,27 @@ void exit_pi_state_list(struct task_struct *curr)
          */
         raw_spin_lock_irq(&curr->pi_lock);
         while (!list_empty(head)) {
-
                 next = head->next;
                 pi_state = list_entry(next, struct futex_pi_state, list);
                 key = pi_state->key;
                 hb = hash_futex(&key);
+
+                /*
+                 * We can race against put_pi_state() removing itself from the
+                 * list (a waiter going away). put_pi_state() will first
+                 * decrement the reference count and then modify the list, so
+                 * its possible to see the list entry but fail this reference
+                 * acquire.
+                 *
+                 * In that case; drop the locks to let put_pi_state() make
+                 * progress and retry the loop.
+                 */
+                if (!atomic_inc_not_zero(&pi_state->refcount)) {
+                        raw_spin_unlock_irq(&curr->pi_lock);
+                        cpu_relax();
+                        raw_spin_lock_irq(&curr->pi_lock);
+                        continue;
+                }
                 raw_spin_unlock_irq(&curr->pi_lock);
 
                 spin_lock(&hb->lock);
@@ -918,8 +934,10 @@ void exit_pi_state_list(struct task_struct *curr)
                  * task still owns the PI-state:
                  */
                 if (head->next != next) {
+                        /* retain curr->pi_lock for the loop invariant */
                         raw_spin_unlock(&pi_state->pi_mutex.wait_lock);
                         spin_unlock(&hb->lock);
+                        put_pi_state(pi_state);
                         continue;
                 }
 
@@ -927,9 +945,8 @@ void exit_pi_state_list(struct task_struct *curr)
                 WARN_ON(list_empty(&pi_state->list));
                 list_del_init(&pi_state->list);
                 pi_state->owner = NULL;
-                raw_spin_unlock(&curr->pi_lock);
 
-                get_pi_state(pi_state);
+                raw_spin_unlock(&curr->pi_lock);
                 raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock);
                 spin_unlock(&hb->lock);
 
@@ -1570,8 +1587,16 @@ static int futex_atomic_op_inuser(unsigned int encoded_op, u32 __user *uaddr)
         int oldval, ret;
 
         if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) {
-                if (oparg < 0 || oparg > 31)
-                        return -EINVAL;
+                if (oparg < 0 || oparg > 31) {
+                        char comm[sizeof(current->comm)];
+                        /*
+                         * kill this print and return -EINVAL when userspace
+                         * is sane again
+                         */
+                        pr_info_ratelimited("futex_wake_op: %s tries to shift op by %d; fix this program\n",
+                                        get_task_comm(comm, current), oparg);
+                        oparg &= 31;
+                }
                 oparg = 1 << oparg;
         }
 
diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c
index 3f409968e466..83f830acbb5f 100644
--- a/kernel/futex_compat.c
+++ b/kernel/futex_compat.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/futex_compat.c
  *
diff --git a/kernel/gcov/Makefile b/kernel/gcov/Makefile
index 752d6486b67e..c6c50e5c680e 100644
--- a/kernel/gcov/Makefile
+++ b/kernel/gcov/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"'
 
 obj-y := base.o fs.o
diff --git a/kernel/gcov/base.c b/kernel/gcov/base.c
index c51a49c9be70..9c7c8d5c18f2 100644
--- a/kernel/gcov/base.c
+++ b/kernel/gcov/base.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  This code maintains a list of active profiling data structures.
  *
diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c
index edf67c493a8e..6e40ff6be083 100644
--- a/kernel/gcov/fs.c
+++ b/kernel/gcov/fs.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  This code exports profiling data as debugfs files to userspace.
  *
diff --git a/kernel/gcov/gcc_3_4.c b/kernel/gcov/gcc_3_4.c
index 27bc88a35013..1e32e66c9563 100644
--- a/kernel/gcov/gcc_3_4.c
+++ b/kernel/gcov/gcc_3_4.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  This code provides functions to handle gcc's profiling data format
  *  introduced with gcc 3.4. Future versions of gcc may change the gcov
diff --git a/kernel/gcov/gcc_4_7.c b/kernel/gcov/gcc_4_7.c
index 46a18e72bce6..ca5e5c0ef853 100644
--- a/kernel/gcov/gcc_4_7.c
+++ b/kernel/gcov/gcc_4_7.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  This code provides functions to handle gcc's profiling data format
  *  introduced with gcc 4.7.
diff --git a/kernel/gcov/gcov.h b/kernel/gcov/gcov.h
index 92c8e22a29ed..de118ad4a024 100644
--- a/kernel/gcov/gcov.h
+++ b/kernel/gcov/gcov.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  *  Profiling infrastructure declarations.
  *
diff --git a/kernel/groups.c b/kernel/groups.c
index 434f6665f187..e357bc800111 100644
--- a/kernel/groups.c
+++ b/kernel/groups.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Supplementary group IDs
  */
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index 1970cafe8f2a..ed15d142694b 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 
 obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o
 obj-$(CONFIG_IRQ_TIMINGS) += timings.o
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index d69bd77252a7..e12d35108225 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2016 Thomas Gleixner.
  * Copyright (C) 2016-2017 Christoph Hellwig.
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
index d30a0dd5cc02..befa671fba64 100644
--- a/kernel/irq/autoprobe.c
+++ b/kernel/irq/autoprobe.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/irq/autoprobe.c
  *
diff --git a/kernel/irq/debug.h b/kernel/irq/debug.h
index e75e29e4434a..17f05ef8f575 100644
--- a/kernel/irq/debug.h
+++ b/kernel/irq/debug.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Debugging printout:
  */
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index a4aa39009f0d..44ed5f8c8759 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * IRQ subsystem internal functions and variables:
  *
diff --git a/kernel/irq/migration.c b/kernel/irq/migration.c
index 6ca054a3f91d..86ae0eb80b53 100644
--- a/kernel/irq/migration.c
+++ b/kernel/irq/migration.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 
 #include <linux/irq.h>
 #include <linux/interrupt.h>
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 6376b4a598d3..c010cc0daf79 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/irq/proc.c
  *
diff --git a/kernel/irq/resend.c b/kernel/irq/resend.c
index b86886beee4f..1d08f45135c2 100644
--- a/kernel/irq/resend.c
+++ b/kernel/irq/resend.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/irq/resend.c
  *
diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h
index 320579d89091..e43795cd2ccf 100644
--- a/kernel/irq/settings.h
+++ b/kernel/irq/settings.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Internal header to deal with irq_desc->status which will be renamed
  * to irq_desc->settings.
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
index 061ba7eed4ed..987d7bca4864 100644
--- a/kernel/irq/spurious.c
+++ b/kernel/irq/spurious.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/irq/spurious.c
  *
diff --git a/kernel/kcmp.c b/kernel/kcmp.c
index 055bb2962a0b..a0e3d7a0e8b8 100644
--- a/kernel/kcmp.c
+++ b/kernel/kcmp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/kernel.h>
 #include <linux/syscalls.h>
 #include <linux/fdtable.h>
diff --git a/kernel/kcov.c b/kernel/kcov.c
index 3f693a0f6f3e..fc6af9e1308b 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #define pr_fmt(fmt) "kcov: " fmt
 
 #define DISABLE_BRANCH_PROFILING
diff --git a/kernel/kexec_internal.h b/kernel/kexec_internal.h
index 50dfcb039a41..48aaf2ac0d0d 100644
--- a/kernel/kexec_internal.h
+++ b/kernel/kexec_internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef LINUX_KEXEC_INTERNAL_H
 #define LINUX_KEXEC_INTERNAL_H
 
diff --git a/kernel/livepatch/core.h b/kernel/livepatch/core.h
index c74f24c47837..a351601d7f76 100644
--- a/kernel/livepatch/core.h
+++ b/kernel/livepatch/core.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LIVEPATCH_CORE_H
 #define _LIVEPATCH_CORE_H
 
diff --git a/kernel/livepatch/patch.h b/kernel/livepatch/patch.h
index 0db227170c36..e72d8250d04b 100644
--- a/kernel/livepatch/patch.h
+++ b/kernel/livepatch/patch.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LIVEPATCH_PATCH_H
 #define _LIVEPATCH_PATCH_H
 
diff --git a/kernel/livepatch/transition.h b/kernel/livepatch/transition.h
index ce09b326546c..0f6e27c481f9 100644
--- a/kernel/livepatch/transition.h
+++ b/kernel/livepatch/transition.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LIVEPATCH_TRANSITION_H
 #define _LIVEPATCH_TRANSITION_H
 
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index 760158d9d98d..392c7f23af76 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # Any varying coverage in these files is non-deterministic
 # and is generally not a function of system call inputs.
 KCOV_INSTRUMENT         := n
diff --git a/kernel/locking/lockdep_internals.h b/kernel/locking/lockdep_internals.h
index 1da4669d57a7..d459d624ba2a 100644
--- a/kernel/locking/lockdep_internals.h
+++ b/kernel/locking/lockdep_internals.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * kernel/lockdep_internals.h
  *
diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c
index 68d9e267ccd4..ad69bbc9bd28 100644
--- a/kernel/locking/lockdep_proc.c
+++ b/kernel/locking/lockdep_proc.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * kernel/lockdep_proc.c
  *
diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h
index 6a385aabcce7..f046b7ce9dd6 100644
--- a/kernel/locking/mcs_spinlock.h
+++ b/kernel/locking/mcs_spinlock.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * MCS lock defines
  *
diff --git a/kernel/locking/mutex-debug.h b/kernel/locking/mutex-debug.h
index 4174417d5309..1edd3f45a4ec 100644
--- a/kernel/locking/mutex-debug.h
+++ b/kernel/locking/mutex-debug.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Mutexes: blocking mutual exclusion locks
  *
diff --git a/kernel/locking/mutex.h b/kernel/locking/mutex.h
index 6ebc1902f779..1c2287d3fa71 100644
--- a/kernel/locking/mutex.h
+++ b/kernel/locking/mutex.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Mutexes: blocking mutual exclusion locks
  *
diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c
index a74ee6abd039..6ef600aa0f47 100644
--- a/kernel/locking/osq_lock.c
+++ b/kernel/locking/osq_lock.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/percpu.h>
 #include <linux/sched.h>
 #include <linux/osq_lock.h>
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 43555681c40b..15b6a39366c6 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _GEN_PV_LOCK_SLOWPATH
 #error "do not include this file"
 #endif
diff --git a/kernel/locking/rtmutex-debug.c b/kernel/locking/rtmutex-debug.c
index f4a74e78d467..fd4fe1f5b458 100644
--- a/kernel/locking/rtmutex-debug.c
+++ b/kernel/locking/rtmutex-debug.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * RT-Mutexes: blocking mutual exclusion locks with PI support
  *
diff --git a/kernel/locking/rtmutex-debug.h b/kernel/locking/rtmutex-debug.h
index 5078c6ddf4a5..fc549713bba3 100644
--- a/kernel/locking/rtmutex-debug.h
+++ b/kernel/locking/rtmutex-debug.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * RT-Mutexes: blocking mutual exclusion locks with PI support
  *
diff --git a/kernel/locking/rtmutex.h b/kernel/locking/rtmutex.h
index 5c253caffe91..732f96abf462 100644
--- a/kernel/locking/rtmutex.h
+++ b/kernel/locking/rtmutex.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * RT-Mutexes: blocking mutual exclusion locks with PI support
  *
diff --git a/kernel/locking/rtmutex_common.h b/kernel/locking/rtmutex_common.h
index 7453be0485a5..124e98ca0b17 100644
--- a/kernel/locking/rtmutex_common.h
+++ b/kernel/locking/rtmutex_common.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * RT Mutexes: blocking mutual exclusion locks with PI support
  *
diff --git a/kernel/locking/rwsem-spinlock.c b/kernel/locking/rwsem-spinlock.c
index 0848634c5512..a7ffb2a96ede 100644
--- a/kernel/locking/rwsem-spinlock.c
+++ b/kernel/locking/rwsem-spinlock.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* rwsem-spinlock.c: R/W semaphores: contention handling functions for
  * generic spinlock implementation
  *
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index 1fefe6dcafd7..e795908f3607 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* rwsem.c: R/W semaphores: contention handling functions
  *
  * Written by David Howells (dhowells@redhat.com).
diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c
index e53f7746d9fd..f549c552dbf1 100644
--- a/kernel/locking/rwsem.c
+++ b/kernel/locking/rwsem.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* kernel/rwsem.c: R/W semaphores, public implementation
  *
  * Written by David Howells (dhowells@redhat.com).
diff --git a/kernel/locking/rwsem.h b/kernel/locking/rwsem.h
index a699f4048ba1..a883b8f1fdc6 100644
--- a/kernel/locking/rwsem.h
+++ b/kernel/locking/rwsem.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * The owner field of the rw_semaphore structure will be set to
  * RWSEM_READ_OWNED when a reader grabs the lock. A writer will clear
diff --git a/kernel/locking/spinlock.c b/kernel/locking/spinlock.c
index 8fd48b5552a7..b96343374a87 100644
--- a/kernel/locking/spinlock.c
+++ b/kernel/locking/spinlock.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (2004) Linus Torvalds
  *
diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index eb4f717705ba..a3f79f0eef36 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 
 ccflags-$(CONFIG_PM_DEBUG)      := -DDEBUG
 
diff --git a/kernel/power/autosleep.c b/kernel/power/autosleep.c
index 9012ecf7b814..41e83a779e19 100644
--- a/kernel/power/autosleep.c
+++ b/kernel/power/autosleep.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * kernel/power/autosleep.c
  *
diff --git a/kernel/power/console.c b/kernel/power/console.c
index 0e781798b0b3..fcdf0e14a47d 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Functions for saving/restoring console.
  *
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 1d2d761e3c25..f29cd178df90 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #include <linux/suspend.h>
 #include <linux/suspend_ioctls.h>
 #include <linux/utsname.h>
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 50f25cb370c6..7381d49a44db 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * drivers/power/process.c - Functions for starting/stopping processes on 
  *                           suspend transitions.
diff --git a/kernel/power/wakelock.c b/kernel/power/wakelock.c
index 1896386e16bb..dfba59be190b 100644
--- a/kernel/power/wakelock.c
+++ b/kernel/power/wakelock.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * kernel/power/wakelock.c
  *
diff --git a/kernel/printk/braille.c b/kernel/printk/braille.c
index 61d41ca41844..1d21ebacfdb8 100644
--- a/kernel/printk/braille.c
+++ b/kernel/printk/braille.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/kernel.h>
diff --git a/kernel/printk/braille.h b/kernel/printk/braille.h
index 749a6756843a..123154f86304 100644
--- a/kernel/printk/braille.h
+++ b/kernel/printk/braille.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _PRINTK_BRAILLE_H
 #define _PRINTK_BRAILLE_H
 
diff --git a/kernel/printk/console_cmdline.h b/kernel/printk/console_cmdline.h
index 2ca4a8b5fe57..11f19c466af5 100644
--- a/kernel/printk/console_cmdline.h
+++ b/kernel/printk/console_cmdline.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _CONSOLE_CMDLINE_H
 #define _CONSOLE_CMDLINE_H
 
diff --git a/kernel/range.c b/kernel/range.c
index 82cfc285b046..d84de6766472 100644
--- a/kernel/range.c
+++ b/kernel/range.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Range add and subtract
  */
diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile
index 13c0fc852767..020e8b6a644b 100644
--- a/kernel/rcu/Makefile
+++ b/kernel/rcu/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 # Any varying coverage in these files is non-deterministic
 # and is generally not a function of system call inputs.
 KCOV_INSTRUMENT := n
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 78f54932ea1d..a9ee16bbc693 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_clock.o = $(CC_FLAGS_FTRACE)
 endif
diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c
index de6d7f4dfcb5..a43df5193538 100644
--- a/kernel/sched/autogroup.c
+++ b/kernel/sched/autogroup.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "sched.h"
 
 #include <linux/proc_fs.h>
diff --git a/kernel/sched/autogroup.h b/kernel/sched/autogroup.h
index ce40c810cd5c..27cd22b89824 100644
--- a/kernel/sched/autogroup.h
+++ b/kernel/sched/autogroup.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifdef CONFIG_SCHED_AUTOGROUP
 
 #include <linux/kref.h>
diff --git a/kernel/sched/completion.c b/kernel/sched/completion.c
index cc873075c3bd..2ddaec40956f 100644
--- a/kernel/sched/completion.c
+++ b/kernel/sched/completion.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Generic wait-for-completion handler;
  *
diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index f95ab29a45d0..44ab32a4fab6 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/cgroup.h>
 #include <linux/slab.h>
 #include <linux/percpu.h>
diff --git a/kernel/sched/cpuacct.h b/kernel/sched/cpuacct.h
index ba72807c73d4..a8358a57a316 100644
--- a/kernel/sched/cpuacct.h
+++ b/kernel/sched/cpuacct.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifdef CONFIG_CGROUP_CPUACCT
 
 extern void cpuacct_charge(struct task_struct *tsk, u64 cputime);
diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h
index f7da8c55bba0..b010d26e108e 100644
--- a/kernel/sched/cpudeadline.h
+++ b/kernel/sched/cpudeadline.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LINUX_CPUDL_H
 #define _LINUX_CPUDL_H
 
diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h
index 63cbb9ca0496..bab050019071 100644
--- a/kernel/sched/cpupri.h
+++ b/kernel/sched/cpupri.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LINUX_CPUPRI_H
 #define _LINUX_CPUPRI_H
 
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 0191ec7667c3..4ae5c1ea90e2 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Deadline Scheduling Class (SCHED_DEADLINE)
  *
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index d3f3094856fe..5c09ddf8c832 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Completely Fair Scheduling (CFS) Class (SCHED_NORMAL/SCHED_BATCH)
  *
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 319ed0e8a347..9552fd5854bf 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Only give sleepers 50% of their service deficit. This allows
  * them to run sooner, but does not allow tons of sleepers to
diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c
index 0c00172db63e..d518664cce4f 100644
--- a/kernel/sched/idle_task.c
+++ b/kernel/sched/idle_task.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "sched.h"
 
 /*
diff --git a/kernel/sched/loadavg.c b/kernel/sched/loadavg.c
index f14716a3522f..89a989e4d758 100644
--- a/kernel/sched/loadavg.c
+++ b/kernel/sched/loadavg.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * kernel/sched/loadavg.c
  *
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 0af5ca9e3e3f..3c96c80e0992 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
  * policies)
diff --git a/kernel/sched/sched-pelt.h b/kernel/sched/sched-pelt.h
index cd200d16529e..a26473674fb7 100644
--- a/kernel/sched/sched-pelt.h
+++ b/kernel/sched/sched-pelt.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /* Generated by Documentation/scheduler/sched-pelt; do not modify. */
 
 static const u32 runnable_avg_yN_inv[] = {
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 14db76cd496f..3b448ba82225 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #include <linux/sched.h>
 #include <linux/sched/autogroup.h>
diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
index 87e2c9f0c33e..940b1fa1d2ce 100644
--- a/kernel/sched/stats.c
+++ b/kernel/sched/stats.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 
 #include <linux/slab.h>
 #include <linux/fs.h>
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
index d5710651043b..baf500d12b7c 100644
--- a/kernel/sched/stats.h
+++ b/kernel/sched/stats.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #ifdef CONFIG_SCHEDSTATS
 
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index 9f69fb630853..45caf90b24cd 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "sched.h"
 
 /*
diff --git a/kernel/sched/swait.c b/kernel/sched/swait.c
index 2227e183e202..9ff1555341ed 100644
--- a/kernel/sched/swait.c
+++ b/kernel/sched/swait.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/sched/signal.h>
 #include <linux/swait.h>
 
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index f1cf4f306a82..6798276d29af 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Scheduler topology setup/handling methods
  */
diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index 8ac79355915b..5f0dfb2abb8d 100644
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/seccomp.c
  *
diff --git a/kernel/signal.c b/kernel/signal.c
index 800a18f77732..8dcd8825b2de 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2698,7 +2698,7 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
                         [SIGSEGV] = { NSIGSEGV, SIL_FAULT },
                         [SIGBUS]  = { NSIGBUS,  SIL_FAULT },
                         [SIGTRAP] = { NSIGTRAP, SIL_FAULT },
-#if defined(SIGMET) && defined(NSIGEMT)
+#if defined(SIGEMT) && defined(NSIGEMT)
                         [SIGEMT]  = { NSIGEMT,  SIL_FAULT },
 #endif
                         [SIGCHLD] = { NSIGCHLD, SIL_CHLD },
diff --git a/kernel/smpboot.h b/kernel/smpboot.h
index 485b81cfab34..34dd3d7ba40b 100644
--- a/kernel/smpboot.h
+++ b/kernel/smpboot.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef SMPBOOT_H
 #define SMPBOOT_H
 
diff --git a/kernel/sys.c b/kernel/sys.c
index 9aebc2935013..524a4cb9bbe2 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *  linux/kernel/sys.c
  *
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 8acef8576ce9..b5189762d275 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 
 #include <linux/linkage.h>
 #include <linux/errno.h>
diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index 58ea8c03662e..e8c0dab4fd65 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/stat.h>
 #include <linux/sysctl.h>
 #include "../fs/xfs/xfs_sysctl.h"
diff --git a/kernel/task_work.c b/kernel/task_work.c
index 9a9f262fc53d..0fef395662a6 100644
--- a/kernel/task_work.c
+++ b/kernel/task_work.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/spinlock.h>
 #include <linux/task_work.h>
 #include <linux/tracehook.h>
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 938dbf33ef49..f1e46f338a9c 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 obj-y += time.o timer.o hrtimer.o
 obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o
 obj-y += timeconv.o timecounter.o alarmtimer.o
diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c
index 2ef98a02376a..f26acef5d7b4 100644
--- a/kernel/time/itimer.c
+++ b/kernel/time/itimer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/itimer.c
  *
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index edf19cc53140..99e03bec68e4 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * NTP state machine interfaces and logic.
  *
diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h
index d8a7c11fa71a..0a53e6ea47b1 100644
--- a/kernel/time/ntp_internal.h
+++ b/kernel/time/ntp_internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _LINUX_NTP_INTERNAL_H
 #define _LINUX_NTP_INTERNAL_H
 
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 8585ad6e472a..5b117110b55b 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Implement CPU time clocks for the POSIX clock interface.
  */
diff --git a/kernel/time/posix-timers.h b/kernel/time/posix-timers.h
index fb303c3be4d3..151e28f5bf30 100644
--- a/kernel/time/posix-timers.h
+++ b/kernel/time/posix-timers.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #define TIMER_RETRY 1
 
 struct k_clock {
diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
index a7bb8f33ae07..58045eb976c3 100644
--- a/kernel/time/tick-broadcast-hrtimer.c
+++ b/kernel/time/tick-broadcast-hrtimer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/kernel/time/tick-broadcast-hrtimer.c
  * This file emulates a local clock event device
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index be0ac01f2e12..f8e1845aa464 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * tick internal variable and functions used by low/high res code
  */
diff --git a/kernel/time/tick-sched.h b/kernel/time/tick-sched.h
index 075444e3d48e..954b43dbf21c 100644
--- a/kernel/time/tick-sched.h
+++ b/kernel/time/tick-sched.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _TICK_SCHED_H
 #define _TICK_SCHED_H
 
diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
index d0914676d4c5..c9f9af339914 100644
--- a/kernel/time/timekeeping.h
+++ b/kernel/time/timekeeping.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _KERNEL_TIME_TIMEKEEPING_H
 #define _KERNEL_TIME_TIMEKEEPING_H
 /*
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h
index 9a18f121f399..fdbeeb02dde9 100644
--- a/kernel/time/timekeeping_internal.h
+++ b/kernel/time/timekeeping_internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _TIMEKEEPING_INTERNAL_H
 #define _TIMEKEEPING_INTERNAL_H
 /*
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 90f2701d92a7..19a15b2f1190 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -1,3 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0
 
 # Do not instrument the tracer itself:
 
diff --git a/kernel/trace/power-traces.c b/kernel/trace/power-traces.c
index 0c7dee221dca..21bb161c2316 100644
--- a/kernel/trace/power-traces.c
+++ b/kernel/trace/power-traces.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Power trace points
  *
diff --git a/kernel/trace/rpm-traces.c b/kernel/trace/rpm-traces.c
index 4b3b5eaf94d1..25dec0b00280 100644
--- a/kernel/trace/rpm-traces.c
+++ b/kernel/trace/rpm-traces.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Power trace points
  *
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 9050c8b3ccde..6b0b343a36a2 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #ifndef _LINUX_KERNEL_TRACE_H
 #define _LINUX_KERNEL_TRACE_H
diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c
index 16a8cf02eee9..79f838a75077 100644
--- a/kernel/trace/trace_benchmark.c
+++ b/kernel/trace/trace_benchmark.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/kthread.h>
diff --git a/kernel/trace/trace_benchmark.h b/kernel/trace/trace_benchmark.h
index ebdbfc2f2a64..be1d86ff753d 100644
--- a/kernel/trace/trace_benchmark.h
+++ b/kernel/trace/trace_benchmark.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM benchmark
 
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 4d8fdf3184dc..4ad967453b6f 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * unlikely profiler
  *
diff --git a/kernel/trace/trace_entries.h b/kernel/trace/trace_entries.h
index adcdbbeae010..e954ae3d82c0 100644
--- a/kernel/trace/trace_entries.h
+++ b/kernel/trace/trace_entries.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * This file defines the trace event structures that go into the ring
  * buffer directly. They are created via macros so that changes for them
diff --git a/kernel/trace/trace_events_filter_test.h b/kernel/trace/trace_events_filter_test.h
index bfd4dba0d603..39d7ef4f57cb 100644
--- a/kernel/trace/trace_events_filter_test.h
+++ b/kernel/trace/trace_events_filter_test.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM test
 
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index 39aa7aa66468..548e62eb5c46 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace_export.c - export basic ftrace utilities to user space
  *
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index a0910c0cdf2e..27f7ad12c4b1 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * ring buffer based function tracer
  *
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index b8f1f54731af..23c0b0cb5fb9 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *
  * Function graph tracer.
diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c
index 57149bce6aad..d953c163a079 100644
--- a/kernel/trace/trace_kdb.c
+++ b/kernel/trace/trace_kdb.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * kdb helper for dumping the ftrace buffer
  *
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index dca78fc48439..b0388016b687 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Memory mapped I/O tracing
  *
diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c
index 49f61fe96a6b..50523f953a5d 100644
--- a/kernel/trace/trace_nop.c
+++ b/kernel/trace/trace_nop.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * nop tracer
  *
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
index fabc49bcd493..dbba03ed96de 100644
--- a/kernel/trace/trace_output.h
+++ b/kernel/trace/trace_output.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __TRACE_EVENTS_H
 #define __TRACE_EVENTS_H
 
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index b341c02730be..e288168661e1 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace context switch
  *
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 0c331978b1a6..7d461dcd4831 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * trace task wakeup timings
  *
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index b17ec642793b..cd70eb5df38e 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /* Include in trace.c */
 
 #include <uapi/linux/sched/types.h>
diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c
index b4c475a0a48b..8cda06a10d66 100644
--- a/kernel/trace/trace_selftest_dynamic.c
+++ b/kernel/trace/trace_selftest_dynamic.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include "trace.h"
 
 int DYN_FTRACE_TEST_NAME(void)
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 780262210c9a..734accc02418 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2008 Steven Rostedt <srostedt@redhat.com>
  *
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index 413ff108fbd0..75bf1bcb4a8a 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Infrastructure for statistic tracing (histogram output).
  *
diff --git a/kernel/trace/trace_stat.h b/kernel/trace/trace_stat.h
index 8f03914b9a6a..76d30b4ebe83 100644
--- a/kernel/trace/trace_stat.h
+++ b/kernel/trace/trace_stat.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __TRACE_STAT_H
 #define __TRACE_STAT_H
 
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 696afe72d3b1..a2a642f2c64f 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 #include <trace/syscall.h>
 #include <trace/events/syscalls.h>
 #include <linux/syscalls.h>
diff --git a/kernel/trace/tracing_map.h b/kernel/trace/tracing_map.h
index 618838f5f30a..ab0ca77331d0 100644
--- a/kernel/trace/tracing_map.h
+++ b/kernel/trace/tracing_map.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 #ifndef __TRACING_MAP_H
 #define __TRACING_MAP_H
 
diff --git a/kernel/uid16.c b/kernel/uid16.c
index 5c2dc5b2bf4f..ce74a4901d2b 100644
--- a/kernel/uid16.c
+++ b/kernel/uid16.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  *      Wrapper functions for 16bit uid back compatibility. All nicely tied
  *      together in the faint hope we can take the out in five years time.
diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 6bcb854909c0..c8e06703e44c 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Detect hard and soft lockups on a system
  *
diff --git a/kernel/watchdog_hld.c b/kernel/watchdog_hld.c
index 71a62ceacdc8..e449a23e9d59 100644
--- a/kernel/watchdog_hld.c
+++ b/kernel/watchdog_hld.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Detect hard lockups on a system
  *
@@ -12,6 +13,7 @@
 #define pr_fmt(fmt) "NMI watchdog: " fmt
 
 #include <linux/nmi.h>
+#include <linux/atomic.h>
 #include <linux/module.h>
 #include <linux/sched/debug.h>
 
@@ -21,10 +23,11 @@
 static DEFINE_PER_CPU(bool, hard_watchdog_warn);
 static DEFINE_PER_CPU(bool, watchdog_nmi_touch);
 static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);
+static DEFINE_PER_CPU(struct perf_event *, dead_event);
 static struct cpumask dead_events_mask;
 
 static unsigned long hardlockup_allcpu_dumped;
-static unsigned int watchdog_cpus;
+static atomic_t watchdog_cpus = ATOMIC_INIT(0);
 
 void arch_touch_nmi_watchdog(void)
 {
@@ -188,7 +191,8 @@ void hardlockup_detector_perf_enable(void)
         if (hardlockup_detector_event_create())
                 return;
 
-        if (!watchdog_cpus++)
+        /* use original value for check */
+        if (!atomic_fetch_inc(&watchdog_cpus))
                 pr_info("Enabled. Permanently consumes one hw-PMU counter.\n");
 
         perf_event_enable(this_cpu_read(watchdog_ev));
@@ -203,8 +207,10 @@ void hardlockup_detector_perf_disable(void)
 
         if (event) {
                 perf_event_disable(event);
+                this_cpu_write(watchdog_ev, NULL);
+                this_cpu_write(dead_event, event);
                 cpumask_set_cpu(smp_processor_id(), &dead_events_mask);
-                watchdog_cpus--;
+                atomic_dec(&watchdog_cpus);
         }
 }
 
@@ -218,7 +224,7 @@ void hardlockup_detector_perf_cleanup(void)
         int cpu;
 
         for_each_cpu(cpu, &dead_events_mask) {
-                struct perf_event *event = per_cpu(watchdog_ev, cpu);
+                struct perf_event *event = per_cpu(dead_event, cpu);
 
                 /*
                  * Required because for_each_cpu() reports  unconditionally
@@ -226,7 +232,7 @@ void hardlockup_detector_perf_cleanup(void)
                  */
                 if (event)
                         perf_event_release_kernel(event);
-                per_cpu(watchdog_ev, cpu) = NULL;
+                per_cpu(dead_event, cpu) = NULL;
         }
         cpumask_clear(&dead_events_mask);
 }
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 160fdc6e839a..1070b21ba4aa 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -68,6 +68,7 @@ enum {
          * attach_mutex to avoid changing binding state while
          * worker_attach_to_pool() is in progress.
          */
+        POOL_MANAGER_ACTIVE     = 1 << 0,       /* being managed */
         POOL_DISASSOCIATED      = 1 << 2,       /* cpu can't serve workers */
 
         /* worker flags */
@@ -165,7 +166,6 @@ struct worker_pool {
                                                 /* L: hash of busy workers */
 
         /* see manage_workers() for details on the two manager mutexes */
-        struct mutex            manager_arb;    /* manager arbitration */
         struct worker           *manager;       /* L: purely informational */
         struct mutex            attach_mutex;   /* attach/detach exclusion */
         struct list_head        workers;        /* A: attached workers */
@@ -299,6 +299,7 @@ static struct workqueue_attrs *wq_update_unbound_numa_attrs_buf;
 
 static DEFINE_MUTEX(wq_pool_mutex);     /* protects pools and workqueues list */
 static DEFINE_SPINLOCK(wq_mayday_lock); /* protects wq->maydays list */
+static DECLARE_WAIT_QUEUE_HEAD(wq_manager_wait); /* wait for manager to go away */
 
 static LIST_HEAD(workqueues);           /* PR: list of all workqueues */
 static bool workqueue_freezing;         /* PL: have wqs started freezing? */
@@ -801,7 +802,7 @@ static bool need_to_create_worker(struct worker_pool *pool)
 /* Do we have too many workers and should some go away? */
 static bool too_many_workers(struct worker_pool *pool)
 {
-        bool managing = mutex_is_locked(&pool->manager_arb);
+        bool managing = pool->flags & POOL_MANAGER_ACTIVE;
         int nr_idle = pool->nr_idle + managing; /* manager is considered idle */
         int nr_busy = pool->nr_workers - nr_idle;
 
@@ -1980,24 +1981,17 @@ static bool manage_workers(struct worker *worker)
 {
         struct worker_pool *pool = worker->pool;
 
-        /*
-         * Anyone who successfully grabs manager_arb wins the arbitration
-         * and becomes the manager.  mutex_trylock() on pool->manager_arb
-         * failure while holding pool->lock reliably indicates that someone
-         * else is managing the pool and the worker which failed trylock
-         * can proceed to executing work items.  This means that anyone
-         * grabbing manager_arb is responsible for actually performing
-         * manager duties.  If manager_arb is grabbed and released without
-         * actual management, the pool may stall indefinitely.
-         */
-        if (!mutex_trylock(&pool->manager_arb))
+        if (pool->flags & POOL_MANAGER_ACTIVE)
                 return false;
+
+        pool->flags |= POOL_MANAGER_ACTIVE;
         pool->manager = worker;
 
         maybe_create_worker(pool);
 
         pool->manager = NULL;
-        mutex_unlock(&pool->manager_arb);
+        pool->flags &= ~POOL_MANAGER_ACTIVE;
+        wake_up(&wq_manager_wait);
         return true;
 }
 
@@ -3235,7 +3229,6 @@ static int init_worker_pool(struct worker_pool *pool)
         setup_timer(&pool->mayday_timer, pool_mayday_timeout,
                     (unsigned long)pool);
 
-        mutex_init(&pool->manager_arb);
         mutex_init(&pool->attach_mutex);
         INIT_LIST_HEAD(&pool->workers);
 
@@ -3305,13 +3298,15 @@ static void put_unbound_pool(struct worker_pool *pool)
         hash_del(&pool->hash_node);
 
         /*
-         * Become the manager and destroy all workers.  Grabbing
-         * manager_arb prevents @pool's workers from blocking on
-         * attach_mutex.
+         * Become the manager and destroy all workers.  This prevents
+         * @pool's workers from blocking on attach_mutex.  We're the last
+         * manager and @pool gets freed with the flag set.
          */
-        mutex_lock(&pool->manager_arb);
-
         spin_lock_irq(&pool->lock);
+        wait_event_lock_irq(wq_manager_wait,
+                            !(pool->flags & POOL_MANAGER_ACTIVE), pool->lock);
+        pool->flags |= POOL_MANAGER_ACTIVE;
+
         while ((worker = first_idle_worker(pool)))
                 destroy_worker(worker);
         WARN_ON(pool->nr_workers || pool->nr_idle);
@@ -3325,8 +3320,6 @@ static void put_unbound_pool(struct worker_pool *pool)
         if (pool->detach_completion)
                 wait_for_completion(pool->detach_completion);
 
-        mutex_unlock(&pool->manager_arb);
-
         /* shut down the timers */
         del_timer_sync(&pool->idle_timer);
         del_timer_sync(&pool->mayday_timer);
diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
index 8635417c587b..d390d1be3748 100644
--- a/kernel/workqueue_internal.h
+++ b/kernel/workqueue_internal.h
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * kernel/workqueue_internal.h
  *
@@ -9,6 +10,7 @@
 
 #include <linux/workqueue.h>
 #include <linux/kthread.h>
+#include <linux/preempt.h>
 
 struct worker_pool;
 
@@ -59,7 +61,7 @@ struct worker {
  */
 static inline struct worker *current_wq_worker(void)
 {
-        if (current->flags & PF_WQ_WORKER)
+        if (in_task() && (current->flags & PF_WQ_WORKER))
                 return kthread_data(current);
         return NULL;
 }