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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Mon, 16 Feb 2015 18:49:10 +0100
Subject: fs/aio: simple simple work
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.17-rt9.tar.xz
|BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:768
|in_atomic(): 1, irqs_disabled(): 0, pid: 26, name: rcuos/2
|2 locks held by rcuos/2/26:
| #0: (rcu_callback){.+.+..}, at: [<ffffffff810b1a12>] rcu_nocb_kthread+0x1e2/0x380
| #1: (rcu_read_lock_sched){.+.+..}, at: [<ffffffff812acd26>] percpu_ref_kill_rcu+0xa6/0x1c0
|Preemption disabled at:[<ffffffff810b1a93>] rcu_nocb_kthread+0x263/0x380
|Call Trace:
| [<ffffffff81582e9e>] dump_stack+0x4e/0x9c
| [<ffffffff81077aeb>] __might_sleep+0xfb/0x170
| [<ffffffff81589304>] rt_spin_lock+0x24/0x70
| [<ffffffff811c5790>] free_ioctx_users+0x30/0x130
| [<ffffffff812ace34>] percpu_ref_kill_rcu+0x1b4/0x1c0
| [<ffffffff810b1a93>] rcu_nocb_kthread+0x263/0x380
| [<ffffffff8106e046>] kthread+0xd6/0xf0
| [<ffffffff81591eec>] ret_from_fork+0x7c/0xb0
replace this preempt_disable() friendly swork.
Reported-By: Mike Galbraith <umgwanakikbuti@gmail.com>
Suggested-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
fs/aio.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -127,6 +127,7 @@ struct kioctx {
long nr_pages;
struct rcu_work free_rwork; /* see free_ioctx() */
+ struct work_struct free_work; /* see free_ioctx() */
/*
* signals when all in-flight requests are done
@@ -612,9 +613,9 @@ static void free_ioctx_reqs(struct percp
* and ctx->users has dropped to 0, so we know no more kiocbs can be submitted -
* now it's safe to cancel any that need to be.
*/
-static void free_ioctx_users(struct percpu_ref *ref)
+static void free_ioctx_users_work(struct work_struct *work)
{
- struct kioctx *ctx = container_of(ref, struct kioctx, users);
+ struct kioctx *ctx = container_of(work, struct kioctx, free_work);
struct aio_kiocb *req;
spin_lock_irq(&ctx->ctx_lock);
@@ -632,6 +633,14 @@ static void free_ioctx_users(struct perc
percpu_ref_put(&ctx->reqs);
}
+static void free_ioctx_users(struct percpu_ref *ref)
+{
+ struct kioctx *ctx = container_of(ref, struct kioctx, users);
+
+ INIT_WORK(&ctx->free_work, free_ioctx_users_work);
+ schedule_work(&ctx->free_work);
+}
+
static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
{
unsigned i, new_nr;
|