diff options
| -rw-r--r-- | kernel/rcu/srcutree.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 155c430c6a73..2e7ed67646db 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -705,9 +705,15 @@ static void srcu_funnel_gp_start(struct srcu_struct *ssp, struct srcu_data *sdp, int idx = rcu_seq_ctr(s) % ARRAY_SIZE(sdp->mynode->srcu_have_cbs); unsigned long sgsne; struct srcu_node *snp; - struct srcu_node *snp_leaf = smp_load_acquire(&sdp->mynode); + struct srcu_node *snp_leaf; unsigned long snp_seq; + /* Ensure that snp node tree is fully initialized before traversing it */ + if (smp_load_acquire(&ssp->srcu_size_state) < SRCU_SIZE_WAIT_BARRIER) + snp_leaf = NULL; + else + snp_leaf = sdp->mynode; + if (snp_leaf) /* Each pass through the loop does one level of the srcu_node tree. */ for (snp = snp_leaf; snp != NULL; snp = snp->srcu_parent) { @@ -889,10 +895,13 @@ static unsigned long srcu_gp_start_if_needed(struct srcu_struct *ssp, bool needgp = false; unsigned long s; struct srcu_data *sdp; + struct srcu_node *sdp_mynode; + int ss_state; check_init_srcu_struct(ssp); idx = srcu_read_lock(ssp); - if (smp_load_acquire(&ssp->srcu_size_state) < SRCU_SIZE_WAIT_CALL) + ss_state = smp_load_acquire(&ssp->srcu_size_state); + if (ss_state < SRCU_SIZE_WAIT_CALL) sdp = per_cpu_ptr(ssp->sda, 0); else sdp = raw_cpu_ptr(ssp->sda); @@ -912,10 +921,17 @@ static unsigned long srcu_gp_start_if_needed(struct srcu_struct *ssp, needexp = true; } spin_unlock_irqrestore_rcu_node(sdp, flags); + + /* Ensure that snp node tree is fully initialized before traversing it */ + if (ss_state < SRCU_SIZE_WAIT_BARRIER) + sdp_mynode = NULL; + else + sdp_mynode = sdp->mynode; + if (needgp) srcu_funnel_gp_start(ssp, sdp, s, do_norm); else if (needexp) - srcu_funnel_exp_start(ssp, smp_load_acquire(&sdp->mynode), s); + srcu_funnel_exp_start(ssp, sdp_mynode, s); srcu_read_unlock(ssp, idx); return s; } |