The patch titled
rcu_do_batch: make ->qlen decrement irq safe
has been added to the -mm tree. Its filename is
rcu_do_batch-make-qlen-decrement-irq-safe.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: rcu_do_batch: make ->qlen decrement irq safe
From: Oleg Nesterov <oleg@xxxxxxxxxx>
rcu_do_batch() decrements rdp->qlen with irqs enabled. This is not good,
it can also be modified by call_rcu() from interrupt.
Decrement ->qlen once with irqs disabled, after a main loop.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Cc: Dipankar Sarma <dipankar@xxxxxxxxxx>
Cc: "Paul E. McKenney" <paulmck@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
kernel/rcupdate.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletion(-)
diff -puN kernel/rcupdate.c~rcu_do_batch-make-qlen-decrement-irq-safe kernel/rcupdate.c
--- a/kernel/rcupdate.c~rcu_do_batch-make-qlen-decrement-irq-safe
+++ a/kernel/rcupdate.c
@@ -241,12 +241,16 @@ static void rcu_do_batch(struct rcu_data
next = rdp->donelist = list->next;
list->func(list);
list = next;
- rdp->qlen--;
if (++count >= rdp->blimit)
break;
}
+
+ local_irq_disable();
+ rdp->qlen -= count;
+ local_irq_enable();
if (rdp->blimit == INT_MAX && rdp->qlen <= qlowmark)
rdp->blimit = blimit;
+
if (!rdp->donelist)
rdp->donetail = &rdp->donelist;
else
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
rcu_do_batch-make-qlen-decrement-irq-safe.patch
git-block.patch
pid-implement-transfer_pid-and-use-it-to-simplify-de_thread.patch
pid-remove-temporary-debug-code-in-attach_pid.patch
rtmutex-clean-up-and-remove-some-extra-spinlocks.patch
rtmutex-clean-up-and-remove-some-extra-spinlocks-more.patch
elf_core_dump-dont-take-tasklist_lock.patch
elf_fdpic_core_dump-dont-take-tasklist_lock.patch
has_stopped_jobs-cleanup.patch
__dequeue_signal-cleanup.patch
do_sched_setscheduler-dont-take-tasklist_lock.patch
introduce-is_rt_policy-helper.patch
sched_setscheduler-fix-policy-checks.patch
reparent_to_init-use-has_rt_policy.patch
copy_process-cosmetic-ioprio-tweak.patch
futex_find_get_task-dont-take-tasklist_lock.patch
sys_get_robust_list-dont-take-tasklist_lock.patch
set-exit_dead-state-in-do_exit-not-in-schedule.patch
kill-pf_dead-flag.patch
introduce-task_dead-state.patch
select_bad_process-kill-a-bogus-pf_dead-task_dead-check.patch
select_bad_process-cleanup-releasing-check.patch
oom_kill_task-cleanup-mm-checks.patch
audit-accounting-tty-locking.patch
proc-readdir-race-fix-take-3-race-fix.patch
vt-rework-the-console-spawning-variables.patch
vt-make-vt_pid-a-struct-pid-making-it-pid-wrap-around-safe.patch
simplify-pid-iterators.patch
file-add-locking-to-f_getown.patch
proc-convert-task_sig-to-use-lock_task_sighand.patch
proc-convert-do_task_stat-to-use-lock_task_sighand.patch
proc-drop-tasklist-lock-in-task_state.patch
proc-properly-compute-tgid_offset.patch
proc-remove-trailing-blank-entry-from-pid_entry-arrays.patch
proc-remove-the-useless-smp-safe-comments-from-proc.patch
proc-comment-what-proc_fill_cache-does.patch
rcu-simplify-improve-batch-tuning.patch
pidhash-temporary-debug-checks.patch
-
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