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-rw-r--r--kernel/bpf/arraymap.c2
-rw-r--r--kernel/bpf/devmap.c10
-rw-r--r--kernel/bpf/hashtab.c4
-rw-r--r--kernel/bpf/sockmap.c43
-rw-r--r--kernel/bpf/verifier.c65
-rw-r--r--kernel/cpu.c5
-rw-r--r--kernel/exit.c4
-rw-r--r--kernel/irq/generic-chip.c15
-rw-r--r--kernel/rcu/srcutree.c2
-rw-r--r--kernel/rcu/sync.c9
-rw-r--r--kernel/rcu/tree.c18
-rw-r--r--kernel/sched/membarrier.c34
-rw-r--r--kernel/workqueue.c37
13 files changed, 170 insertions, 78 deletions
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 98c0f00c3f5e..e2636737b69b 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -98,7 +98,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
array_size += (u64) attr->max_entries * elem_size * num_possible_cpus();
if (array_size >= U32_MAX - PAGE_SIZE ||
- elem_size > PCPU_MIN_UNIT_SIZE || bpf_array_alloc_percpu(array)) {
+ bpf_array_alloc_percpu(array)) {
bpf_map_area_free(array);
return ERR_PTR(-ENOMEM);
}
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index e093d9a2c4dd..e745d6a88224 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -69,7 +69,7 @@ static LIST_HEAD(dev_map_list);
static u64 dev_map_bitmap_size(const union bpf_attr *attr)
{
- return BITS_TO_LONGS(attr->max_entries) * sizeof(unsigned long);
+ return BITS_TO_LONGS((u64) attr->max_entries) * sizeof(unsigned long);
}
static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
@@ -78,6 +78,9 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
int err = -EINVAL;
u64 cost;
+ if (!capable(CAP_NET_ADMIN))
+ return ERR_PTR(-EPERM);
+
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size != 4 || attr->map_flags & ~BPF_F_NUMA_NODE)
@@ -111,8 +114,9 @@ static struct bpf_map *dev_map_alloc(union bpf_attr *attr)
err = -ENOMEM;
/* A per cpu bitfield with a bit per possible net device */
- dtab->flush_needed = __alloc_percpu(dev_map_bitmap_size(attr),
- __alignof__(unsigned long));
+ dtab->flush_needed = __alloc_percpu_gfp(dev_map_bitmap_size(attr),
+ __alignof__(unsigned long),
+ GFP_KERNEL | __GFP_NOWARN);
if (!dtab->flush_needed)
goto free_dtab;
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 431126f31ea3..6533f08d1238 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -317,10 +317,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
*/
goto free_htab;
- if (percpu && round_up(htab->map.value_size, 8) > PCPU_MIN_UNIT_SIZE)
- /* make sure the size for pcpu_alloc() is reasonable */
- goto free_htab;
-
htab->elem_size = sizeof(struct htab_elem) +
round_up(htab->map.key_size, 8);
if (percpu)
diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c
index 6424ce0e4969..66f00a2b27f4 100644
--- a/kernel/bpf/sockmap.c
+++ b/kernel/bpf/sockmap.c
@@ -39,6 +39,7 @@
#include <linux/workqueue.h>
#include <linux/list.h>
#include <net/strparser.h>
+#include <net/tcp.h>
struct bpf_stab {
struct bpf_map map;
@@ -92,6 +93,14 @@ 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);
+}
+
static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb)
{
struct bpf_prog *prog = READ_ONCE(psock->bpf_verdict);
@@ -101,12 +110,20 @@ static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb)
return SK_DROP;
skb_orphan(skb);
+ /* We need to ensure that BPF metadata for maps is also cleared
+ * when we orphan the skb so that we don't have the possibility
+ * to reference a stale map.
+ */
+ 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;
+ 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)
@@ -114,17 +131,10 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
struct sock *sk;
int rc;
- /* Because we use per cpu values to feed input from sock redirect
- * in BPF program to do_sk_redirect_map() call we need to ensure we
- * are not preempted. RCU read lock is not sufficient in this case
- * with CONFIG_PREEMPT_RCU enabled so we must be explicit here.
- */
- preempt_disable();
rc = smap_verdict_func(psock, skb);
switch (rc) {
case SK_REDIRECT:
- sk = do_sk_redirect_map();
- preempt_enable();
+ sk = do_sk_redirect_map(skb);
if (likely(sk)) {
struct smap_psock *peer = smap_psock_sk(sk);
@@ -141,8 +151,6 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb)
/* Fall through and free skb otherwise */
case SK_DROP:
default:
- if (rc != SK_REDIRECT)
- preempt_enable();
kfree_skb(skb);
}
}
@@ -369,7 +377,7 @@ 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();
@@ -487,6 +495,9 @@ static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
int err = -EINVAL;
u64 cost;
+ if (!capable(CAP_NET_ADMIN))
+ return ERR_PTR(-EPERM);
+
/* check sanity of attributes */
if (attr->max_entries == 0 || attr->key_size != 4 ||
attr->value_size != 4 || attr->map_flags & ~BPF_F_NUMA_NODE)
@@ -840,6 +851,12 @@ static int sock_map_update_elem(struct bpf_map *map,
return -EINVAL;
}
+ if (skops.sk->sk_type != SOCK_STREAM ||
+ skops.sk->sk_protocol != IPPROTO_TCP) {
+ fput(socket->file);
+ return -EOPNOTSUPP;
+ }
+
err = sock_map_ctx_update_elem(&skops, map, key, flags);
fput(socket->file);
return err;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 8b8d6ba39e23..c48ca2a34b5e 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1116,7 +1116,12 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
/* ctx accesses must be at a fixed offset, so that we can
* determine what type of data were returned.
*/
- if (!tnum_is_const(reg->var_off)) {
+ if (reg->off) {
+ verbose("dereference of modified ctx ptr R%d off=%d+%d, ctx+const is allowed, ctx+const+const is not\n",
+ regno, reg->off, off - reg->off);
+ return -EACCES;
+ }
+ if (!tnum_is_const(reg->var_off) || reg->var_off.value) {
char tn_buf[48];
tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
@@ -1124,7 +1129,6 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
tn_buf, off, size);
return -EACCES;
}
- off += reg->var_off.value;
err = check_ctx_access(env, insn_idx, off, size, t, &reg_type);
if (!err && t == BPF_READ && value_regno >= 0) {
/* ctx access returns either a scalar, or a
@@ -2426,12 +2430,15 @@ static int check_alu_op(struct bpf_verifier_env *env, struct bpf_insn *insn)
}
static void find_good_pkt_pointers(struct bpf_verifier_state *state,
- struct bpf_reg_state *dst_reg)
+ struct bpf_reg_state *dst_reg,
+ bool range_right_open)
{
struct bpf_reg_state *regs = state->regs, *reg;
+ u16 new_range;
int i;
- if (dst_reg->off < 0)
+ if (dst_reg->off < 0 ||
+ (dst_reg->off == 0 && range_right_open))
/* This doesn't give us any range */
return;
@@ -2442,9 +2449,13 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state,
*/
return;
- /* LLVM can generate four kind of checks:
+ new_range = dst_reg->off;
+ if (range_right_open)
+ new_range--;
+
+ /* Examples for register markings:
*
- * Type 1/2:
+ * pkt_data in dst register:
*
* r2 = r3;
* r2 += 8;
@@ -2461,7 +2472,7 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state,
* r2=pkt(id=n,off=8,r=0)
* r3=pkt(id=n,off=0,r=0)
*
- * Type 3/4:
+ * pkt_data in src register:
*
* r2 = r3;
* r2 += 8;
@@ -2479,7 +2490,9 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state,
* r3=pkt(id=n,off=0,r=0)
*
* Find register r3 and mark its range as r3=pkt(id=n,off=0,r=8)
- * so that range of bytes [r3, r3 + 8) is safe to access.
+ * or r3=pkt(id=n,off=0,r=8-1), so that range of bytes [r3, r3 + 8)
+ * and [r3, r3 + 8-1) respectively is safe to access depending on
+ * the check.
*/
/* If our ids match, then we must have the same max_value. And we
@@ -2490,14 +2503,14 @@ static void find_good_pkt_pointers(struct bpf_verifier_state *state,
for (i = 0; i < MAX_BPF_REG; i++)
if (regs[i].type == PTR_TO_PACKET && regs[i].id == dst_reg->id)
/* keep the maximum range already checked */
- regs[i].range = max_t(u16, regs[i].range, dst_reg->off);
+ regs[i].range = max(regs[i].range, new_range);
for (i = 0; i < MAX_BPF_STACK; i += BPF_REG_SIZE) {
if (state->stack_slot_type[i] != STACK_SPILL)
continue;
reg = &state->spilled_regs[i / BPF_REG_SIZE];
if (reg->type == PTR_TO_PACKET && reg->id == dst_reg->id)
- reg->range = max_t(u16, reg->range, dst_reg->off);
+ reg->range = max(reg->range, new_range);
}
}
@@ -2861,19 +2874,43 @@ static int check_cond_jmp_op(struct bpf_verifier_env *env,
} else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT &&
dst_reg->type == PTR_TO_PACKET &&
regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- find_good_pkt_pointers(this_branch, dst_reg);
+ /* pkt_data' > pkt_end */
+ find_good_pkt_pointers(this_branch, dst_reg, false);
+ } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGT &&
+ dst_reg->type == PTR_TO_PACKET_END &&
+ regs[insn->src_reg].type == PTR_TO_PACKET) {
+ /* pkt_end > pkt_data' */
+ find_good_pkt_pointers(other_branch, &regs[insn->src_reg], true);
} else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT &&
dst_reg->type == PTR_TO_PACKET &&
regs[insn->src_reg].type == PTR_TO_PACKET_END) {
- find_good_pkt_pointers(other_branch, dst_reg);
+ /* pkt_data' < pkt_end */
+ find_good_pkt_pointers(other_branch, dst_reg, true);
+ } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLT &&
+ dst_reg->type == PTR_TO_PACKET_END &&
+ regs[insn->src_reg].type == PTR_TO_PACKET) {
+ /* pkt_end < pkt_data' */
+ find_good_pkt_pointers(this_branch, &regs[insn->src_reg], false);
+ } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE &&
+ dst_reg->type == PTR_TO_PACKET &&
+ regs[insn->src_reg].type == PTR_TO_PACKET_END) {
+ /* pkt_data' >= pkt_end */
+ find_good_pkt_pointers(this_branch, dst_reg, true);
} else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JGE &&
dst_reg->type == PTR_TO_PACKET_END &&
regs[insn->src_reg].type == PTR_TO_PACKET) {
- find_good_pkt_pointers(other_branch, &regs[insn->src_reg]);
+ /* pkt_end >= pkt_data' */
+ find_good_pkt_pointers(other_branch, &regs[insn->src_reg], false);
+ } else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE &&
+ dst_reg->type == PTR_TO_PACKET &&
+ regs[insn->src_reg].type == PTR_TO_PACKET_END) {
+ /* pkt_data' <= pkt_end */
+ find_good_pkt_pointers(other_branch, dst_reg, false);
} else if (BPF_SRC(insn->code) == BPF_X && opcode == BPF_JLE &&
dst_reg->type == PTR_TO_PACKET_END &&
regs[insn->src_reg].type == PTR_TO_PACKET) {
- find_good_pkt_pointers(this_branch, &regs[insn->src_reg]);
+ /* pkt_end <= pkt_data' */
+ find_good_pkt_pointers(this_branch, &regs[insn->src_reg], true);
} else if (is_pointer_value(env, insn->dst_reg)) {
verbose("R%d pointer comparison prohibited\n", insn->dst_reg);
return -EACCES;
diff --git a/kernel/cpu.c b/kernel/cpu.c
index d851df22f5c5..04892a82f6ac 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -632,6 +632,11 @@ cpuhp_invoke_ap_callback(int cpu, enum cpuhp_state state, bool bringup,
__cpuhp_kick_ap(st);
}
+ /*
+ * Clean up the leftovers so the next hotplug operation wont use stale
+ * data.
+ */
+ st->node = st->last = NULL;
return ret;
}
diff --git a/kernel/exit.c b/kernel/exit.c
index cf28528842bc..f6cad39f35df 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -1611,7 +1611,7 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
return err;
if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
- goto Efault;
+ return -EFAULT;
user_access_begin();
unsafe_put_user(signo, &infop->si_signo, Efault);
@@ -1739,7 +1739,7 @@ COMPAT_SYSCALL_DEFINE5(waitid,
return err;
if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
- goto Efault;
+ return -EFAULT;
user_access_begin();
unsafe_put_user(signo, &infop->si_signo, Efault);
diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index 5270a54b9fa4..c26c5bb6b491 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -135,17 +135,26 @@ void irq_gc_ack_clr_bit(struct irq_data *d)
}
/**
- * irq_gc_mask_disable_reg_and_ack - Mask and ack pending interrupt
+ * irq_gc_mask_disable_and_ack_set - Mask and ack pending interrupt
* @d: irq_data
+ *
+ * This generic implementation of the irq_mask_ack method is for chips
+ * with separate enable/disable registers instead of a single mask
+ * register and where a pending interrupt is acknowledged by setting a
+ * bit.
+ *
+ * Note: This is the only permutation currently used. Similar generic
+ * functions should be added here if other permutations are required.
*/
-void irq_gc_mask_disable_reg_and_ack(struct irq_data *d)
+void irq_gc_mask_disable_and_ack_set(struct irq_data *d)
{
struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
struct irq_chip_type *ct = irq_data_get_chip_type(d);
u32 mask = d->mask;
irq_gc_lock(gc);
- irq_reg_writel(gc, mask, ct->regs.mask);
+ irq_reg_writel(gc, mask, ct->regs.disable);
+ *ct->mask_cache &= ~mask;
irq_reg_writel(gc, mask, ct->regs.ack);
irq_gc_unlock(gc);
}
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c
index 729a8706751d..6d5880089ff6 100644
--- a/kernel/rcu/srcutree.c
+++ b/kernel/rcu/srcutree.c
@@ -854,7 +854,7 @@ void __call_srcu(struct srcu_struct *sp, struct rcu_head *rhp,
/**
* call_srcu() - Queue a callback for invocation after an SRCU grace period
* @sp: srcu_struct in queue the callback
- * @head: structure to be used for queueing the SRCU callback.
+ * @rhp: structure to be used for queueing the SRCU callback.
* @func: function to be invoked after the SRCU grace period
*
* The callback function will be invoked some time after a full SRCU
diff --git a/kernel/rcu/sync.c b/kernel/rcu/sync.c
index 50d1861f7759..3f943efcf61c 100644
--- a/kernel/rcu/sync.c
+++ b/kernel/rcu/sync.c
@@ -85,6 +85,9 @@ void rcu_sync_init(struct rcu_sync *rsp, enum rcu_sync_type type)
}
/**
+ * rcu_sync_enter_start - Force readers onto slow path for multiple updates
+ * @rsp: Pointer to rcu_sync structure to use for synchronization
+ *
* Must be called after rcu_sync_init() and before first use.
*
* Ensures rcu_sync_is_idle() returns false and rcu_sync_{enter,exit}()
@@ -142,7 +145,7 @@ void rcu_sync_enter(struct rcu_sync *rsp)
/**
* rcu_sync_func() - Callback function managing reader access to fastpath
- * @rsp: Pointer to rcu_sync structure to use for synchronization
+ * @rhp: Pointer to rcu_head in rcu_sync structure to use for synchronization
*
* This function is passed to one of the call_rcu() functions by
* rcu_sync_exit(), so that it is invoked after a grace period following the
@@ -158,9 +161,9 @@ void rcu_sync_enter(struct rcu_sync *rsp)
* rcu_sync_exit(). Otherwise, set all state back to idle so that readers
* can again use their fastpaths.
*/
-static void rcu_sync_func(struct rcu_head *rcu)
+static void rcu_sync_func(struct rcu_head *rhp)
{
- struct rcu_sync *rsp = container_of(rcu, struct rcu_sync, cb_head);
+ struct rcu_sync *rsp = container_of(rhp, struct rcu_sync, cb_head);
unsigned long flags;
BUG_ON(rsp->gp_state != GP_PASSED);
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index b0ad62b0e7b8..3e3650e94ae6 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3097,9 +3097,10 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func,
* read-side critical sections have completed. call_rcu_sched() assumes
* that the read-side critical sections end on enabling of preemption
* or on voluntary preemption.
- * RCU read-side critical sections are delimited by :
- * - rcu_read_lock_sched() and rcu_read_unlock_sched(), OR
- * - anything that disables preemption.
+ * RCU read-side critical sections are delimited by:
+ *
+ * - rcu_read_lock_sched() and rcu_read_unlock_sched(), OR
+ * - anything that disables preemption.
*
* These may be nested.
*
@@ -3124,11 +3125,12 @@ EXPORT_SYMBOL_GPL(call_rcu_sched);
* handler. This means that read-side critical sections in process
* context must not be interrupted by softirqs. This interface is to be
* used when most of the read-side critical sections are in softirq context.
- * RCU read-side critical sections are delimited by :
- * - rcu_read_lock() and rcu_read_unlock(), if in interrupt context.
- * OR
- * - rcu_read_lock_bh() and rcu_read_unlock_bh(), if in process context.
- * These may be nested.
+ * RCU read-side critical sections are delimited by:
+ *
+ * - rcu_read_lock() and rcu_read_unlock(), if in interrupt context, OR
+ * - rcu_read_lock_bh() and rcu_read_unlock_bh(), if in process context.
+ *
+ * These may be nested.
*
* See the description of call_rcu() for more detailed information on
* memory ordering guarantees.
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index a92fddc22747..dd7908743dab 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -18,6 +18,7 @@
#include <linux/membarrier.h>
#include <linux/tick.h>
#include <linux/cpumask.h>
+#include <linux/atomic.h>
#include "sched.h" /* for cpu_rq(). */
@@ -26,21 +27,26 @@
* except MEMBARRIER_CMD_QUERY.
*/
#define MEMBARRIER_CMD_BITMASK \
- (MEMBARRIER_CMD_SHARED | MEMBARRIER_CMD_PRIVATE_EXPEDITED)
+ (MEMBARRIER_CMD_SHARED | MEMBARRIER_CMD_PRIVATE_EXPEDITED \
+ | MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED)
static void ipi_mb(void *info)
{
smp_mb(); /* IPIs should be serializing but paranoid. */
}
-static void membarrier_private_expedited(void)
+static int membarrier_private_expedited(void)
{
int cpu;
bool fallback = false;
cpumask_var_t tmpmask;
+ if (!(atomic_read(&current->mm->membarrier_state)
+ & MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY))
+ return -EPERM;
+
if (num_online_cpus() == 1)
- return;
+ return 0;
/*
* Matches memory barriers around rq->curr modification in
@@ -94,6 +100,24 @@ static void membarrier_private_expedited(void)
* rq->curr modification in scheduler.
*/
smp_mb(); /* exit from system call is not a mb */
+ return 0;
+}
+
+static void membarrier_register_private_expedited(void)
+{
+ struct task_struct *p = current;
+ struct mm_struct *mm = p->mm;
+
+ /*
+ * We need to consider threads belonging to different thread
+ * groups, which use the same mm. (CLONE_VM but not
+ * CLONE_THREAD).
+ */
+ if (atomic_read(&mm->membarrier_state)
+ & MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY)
+ return;
+ atomic_or(MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY,
+ &mm->membarrier_state);
}
/**
@@ -144,7 +168,9 @@ SYSCALL_DEFINE2(membarrier, int, cmd, int, flags)
synchronize_sched();
return 0;
case MEMBARRIER_CMD_PRIVATE_EXPEDITED:
- membarrier_private_expedited();
+ return membarrier_private_expedited();
+ case MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED:
+ membarrier_register_private_expedited();
return 0;
default:
return -EINVAL;
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 64d0edf428f8..a2dccfe1acec 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;
}
@@ -3248,7 +3242,6 @@ 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);
@@ -3318,13 +3311,15 @@ 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);
@@ -3338,8 +3333,6 @@ 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);
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