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authorLinus Torvalds <torvalds@linux-foundation.org>2021-03-19 17:01:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-03-19 17:01:09 -0700
commit0ada2dad8bf39857f25e6ecbf68bb1664ca1ee5b (patch)
treeb5023b73d0f482f594cfa82f374c7d0081a1249a
parentecd8ee7f9c1af253738ca4321509ddee727d468d (diff)
parentde75a3d3f5a14c9ab3c4883de3471d3c92a8ee78 (diff)
downloadlinux-stericsson-0ada2dad8bf39857f25e6ecbf68bb1664ca1ee5b.tar.gz
Merge tag 'io_uring-5.12-2021-03-19' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe: "Quieter week this time, which was both expected and desired. About half of the below is fixes for this release, the other half are just fixes in general. In detail: - Fix the freezing of IO threads, by making the freezer not send them fake signals. Make them freezable by default. - Like we did for personalities, move the buffer IDR to xarray. Kills some code and avoids a use-after-free on teardown. - SQPOLL cleanups and fixes (Pavel) - Fix linked timeout race (Pavel) - Fix potential completion post use-after-free (Pavel) - Cleanup and move internal structures outside of general kernel view (Stefan) - Use MSG_SIGNAL for send/recv from io_uring (Stefan)" * tag 'io_uring-5.12-2021-03-19' of git://git.kernel.dk/linux-block: io_uring: don't leak creds on SQO attach error io_uring: use typesafe pointers in io_uring_task io_uring: remove structures from include/linux/io_uring.h io_uring: imply MSG_NOSIGNAL for send[msg]()/recv[msg]() calls io_uring: fix sqpoll cancellation via task_work io_uring: add generic callback_head helpers io_uring: fix concurrent parking io_uring: halt SQO submission on ctx exit io_uring: replace sqd rw_semaphore with mutex io_uring: fix complete_post use ctx after free io_uring: fix ->flags races by linked timeouts io_uring: convert io_buffer_idr to XArray io_uring: allow IO worker threads to be frozen kernel: freezer should treat PF_IO_WORKER like PF_KTHREAD for freezing
-rw-r--r--fs/io-wq.c6
-rw-r--r--fs/io-wq.h10
-rw-r--r--fs/io_uring.c228
-rw-r--r--include/linux/io_uring.h25
-rw-r--r--kernel/fork.c1
-rw-r--r--kernel/freezer.c2
6 files changed, 142 insertions, 130 deletions
diff --git a/fs/io-wq.c b/fs/io-wq.c
index 0ae9ecadf295..e05f996d088f 100644
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -488,6 +488,8 @@ static int io_wqe_worker(void *data)
set_task_comm(current, buf);
while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
+ long ret;
+
set_current_state(TASK_INTERRUPTIBLE);
loop:
raw_spin_lock_irq(&wqe->lock);
@@ -498,7 +500,8 @@ loop:
__io_worker_idle(wqe, worker);
raw_spin_unlock_irq(&wqe->lock);
io_flush_signals();
- if (schedule_timeout(WORKER_IDLE_TIMEOUT))
+ ret = schedule_timeout(WORKER_IDLE_TIMEOUT);
+ if (try_to_freeze() || ret)
continue;
if (fatal_signal_pending(current))
break;
@@ -709,6 +712,7 @@ static int io_wq_manager(void *data)
set_current_state(TASK_INTERRUPTIBLE);
io_wq_check_workers(wq);
schedule_timeout(HZ);
+ try_to_freeze();
if (fatal_signal_pending(current))
set_bit(IO_WQ_BIT_EXIT, &wq->state);
} while (!test_bit(IO_WQ_BIT_EXIT, &wq->state));
diff --git a/fs/io-wq.h b/fs/io-wq.h
index 1ac2f3248088..80d590564ff9 100644
--- a/fs/io-wq.h
+++ b/fs/io-wq.h
@@ -2,7 +2,6 @@
#define INTERNAL_IO_WQ_H
#include <linux/refcount.h>
-#include <linux/io_uring.h>
struct io_wq;
@@ -21,6 +20,15 @@ enum io_wq_cancel {
IO_WQ_CANCEL_NOTFOUND, /* work not found */
};
+struct io_wq_work_node {
+ struct io_wq_work_node *next;
+};
+
+struct io_wq_work_list {
+ struct io_wq_work_node *first;
+ struct io_wq_work_node *last;
+};
+
static inline void wq_list_add_after(struct io_wq_work_node *node,
struct io_wq_work_node *pos,
struct io_wq_work_list *list)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index a4bce17af506..ea2d3e120555 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -258,7 +258,8 @@ enum {
struct io_sq_data {
refcount_t refs;
- struct rw_semaphore rw_lock;
+ atomic_t park_pending;
+ struct mutex lock;
/* ctx's that are using this sqd */
struct list_head ctx_list;
@@ -273,6 +274,7 @@ struct io_sq_data {
unsigned long state;
struct completion exited;
+ struct callback_head *park_task_work;
};
#define IO_IOPOLL_BATCH 8
@@ -402,7 +404,7 @@ struct io_ring_ctx {
struct socket *ring_sock;
#endif
- struct idr io_buffer_idr;
+ struct xarray io_buffers;
struct xarray personalities;
u32 pers_next;
@@ -454,6 +456,22 @@ struct io_ring_ctx {
struct list_head tctx_list;
};
+struct io_uring_task {
+ /* submission side */
+ struct xarray xa;
+ struct wait_queue_head wait;
+ const struct io_ring_ctx *last;
+ struct io_wq *io_wq;
+ struct percpu_counter inflight;
+ atomic_t in_idle;
+ bool sqpoll;
+
+ spinlock_t task_lock;
+ struct io_wq_work_list task_list;
+ unsigned long task_state;
+ struct callback_head task_work;
+};
+
/*
* First field must be the file pointer in all the
* iocb unions! See also 'struct kiocb' in <linux/fs.h>
@@ -1135,7 +1153,7 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
init_waitqueue_head(&ctx->cq_wait);
INIT_LIST_HEAD(&ctx->cq_overflow_list);
init_completion(&ctx->ref_comp);
- idr_init(&ctx->io_buffer_idr);
+ xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
mutex_init(&ctx->uring_lock);
init_waitqueue_head(&ctx->wait);
@@ -1550,14 +1568,17 @@ static void io_req_complete_post(struct io_kiocb *req, long res,
io_put_task(req->task, 1);
list_add(&req->compl.list, &cs->locked_free_list);
cs->locked_free_nr++;
- } else
- req = NULL;
+ } else {
+ if (!percpu_ref_tryget(&ctx->refs))
+ req = NULL;
+ }
io_commit_cqring(ctx);
spin_unlock_irqrestore(&ctx->completion_lock, flags);
- io_cqring_ev_posted(ctx);
- if (req)
+ if (req) {
+ io_cqring_ev_posted(ctx);
percpu_ref_put(&ctx->refs);
+ }
}
static void io_req_complete_state(struct io_kiocb *req, long res,
@@ -1925,17 +1946,44 @@ static int io_req_task_work_add(struct io_kiocb *req)
return ret;
}
-static void io_req_task_work_add_fallback(struct io_kiocb *req,
- task_work_func_t cb)
+static bool io_run_task_work_head(struct callback_head **work_head)
+{
+ struct callback_head *work, *next;
+ bool executed = false;
+
+ do {
+ work = xchg(work_head, NULL);
+ if (!work)
+ break;
+
+ do {
+ next = work->next;
+ work->func(work);
+ work = next;
+ cond_resched();
+ } while (work);
+ executed = true;
+ } while (1);
+
+ return executed;
+}
+
+static void io_task_work_add_head(struct callback_head **work_head,
+ struct callback_head *task_work)
{
- struct io_ring_ctx *ctx = req->ctx;
struct callback_head *head;
- init_task_work(&req->task_work, cb);
do {
- head = READ_ONCE(ctx->exit_task_work);
- req->task_work.next = head;
- } while (cmpxchg(&ctx->exit_task_work, head, &req->task_work) != head);
+ head = READ_ONCE(*work_head);
+ task_work->next = head;
+ } while (cmpxchg(work_head, head, task_work) != head);
+}
+
+static void io_req_task_work_add_fallback(struct io_kiocb *req,
+ task_work_func_t cb)
+{
+ init_task_work(&req->task_work, cb);
+ io_task_work_add_head(&req->ctx->exit_task_work, &req->task_work);
}
static void __io_req_task_cancel(struct io_kiocb *req, int error)
@@ -2843,7 +2891,7 @@ static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
lockdep_assert_held(&req->ctx->uring_lock);
- head = idr_find(&req->ctx->io_buffer_idr, bgid);
+ head = xa_load(&req->ctx->io_buffers, bgid);
if (head) {
if (!list_empty(&head->list)) {
kbuf = list_last_entry(&head->list, struct io_buffer,
@@ -2851,7 +2899,7 @@ static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
list_del(&kbuf->list);
} else {
kbuf = head;
- idr_remove(&req->ctx->io_buffer_idr, bgid);
+ xa_erase(&req->ctx->io_buffers, bgid);
}
if (*len > kbuf->len)
*len = kbuf->len;
@@ -3892,7 +3940,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
}
i++;
kfree(buf);
- idr_remove(&ctx->io_buffer_idr, bgid);
+ xa_erase(&ctx->io_buffers, bgid);
return i;
}
@@ -3910,7 +3958,7 @@ static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
lockdep_assert_held(&ctx->uring_lock);
ret = -ENOENT;
- head = idr_find(&ctx->io_buffer_idr, p->bgid);
+ head = xa_load(&ctx->io_buffers, p->bgid);
if (head)
ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
if (ret < 0)
@@ -3993,21 +4041,14 @@ static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
lockdep_assert_held(&ctx->uring_lock);
- list = head = idr_find(&ctx->io_buffer_idr, p->bgid);
+ list = head = xa_load(&ctx->io_buffers, p->bgid);
ret = io_add_buffers(p, &head);
- if (ret < 0)
- goto out;
-
- if (!list) {
- ret = idr_alloc(&ctx->io_buffer_idr, head, p->bgid, p->bgid + 1,
- GFP_KERNEL);
- if (ret < 0) {
+ if (ret >= 0 && !list) {
+ ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
+ if (ret < 0)
__io_remove_buffers(ctx, head, p->bgid, -1U);
- goto out;
- }
}
-out:
if (ret < 0)
req_set_fail_links(req);
@@ -4359,7 +4400,7 @@ static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
kmsg = &iomsg;
}
- flags = req->sr_msg.msg_flags;
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
else if (issue_flags & IO_URING_F_NONBLOCK)
@@ -4403,7 +4444,7 @@ static int io_send(struct io_kiocb *req, unsigned int issue_flags)
msg.msg_controllen = 0;
msg.msg_namelen = 0;
- flags = req->sr_msg.msg_flags;
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
else if (issue_flags & IO_URING_F_NONBLOCK)
@@ -4593,7 +4634,7 @@ static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
1, req->sr_msg.len);
}
- flags = req->sr_msg.msg_flags;
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
else if (force_nonblock)
@@ -4652,7 +4693,7 @@ static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
msg.msg_iocb = NULL;
msg.msg_flags = 0;
- flags = req->sr_msg.msg_flags;
+ flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
if (flags & MSG_DONTWAIT)
req->flags |= REQ_F_NOWAIT;
else if (force_nonblock)
@@ -6204,7 +6245,6 @@ static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
spin_unlock_irqrestore(&ctx->completion_lock, flags);
if (prev) {
- req_set_fail_links(prev);
io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
io_put_req_deferred(prev, 1);
} else {
@@ -6694,17 +6734,17 @@ static int io_sq_thread(void *data)
set_cpus_allowed_ptr(current, cpu_online_mask);
current->flags |= PF_NO_SETAFFINITY;
- down_read(&sqd->rw_lock);
-
+ mutex_lock(&sqd->lock);
while (!test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state)) {
int ret;
bool cap_entries, sqt_spin, needs_sched;
if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state)) {
- up_read(&sqd->rw_lock);
+ mutex_unlock(&sqd->lock);
cond_resched();
- down_read(&sqd->rw_lock);
+ mutex_lock(&sqd->lock);
io_run_task_work();
+ io_run_task_work_head(&sqd->park_task_work);
timeout = jiffies + sqd->sq_thread_idle;
continue;
}
@@ -6750,32 +6790,28 @@ static int io_sq_thread(void *data)
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
io_ring_set_wakeup_flag(ctx);
- up_read(&sqd->rw_lock);
+ mutex_unlock(&sqd->lock);
schedule();
- down_read(&sqd->rw_lock);
+ try_to_freeze();
+ mutex_lock(&sqd->lock);
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
io_ring_clear_wakeup_flag(ctx);
}
finish_wait(&sqd->wait, &wait);
+ io_run_task_work_head(&sqd->park_task_work);
timeout = jiffies + sqd->sq_thread_idle;
}
- up_read(&sqd->rw_lock);
- down_write(&sqd->rw_lock);
- /*
- * someone may have parked and added a cancellation task_work, run
- * it first because we don't want it in io_uring_cancel_sqpoll()
- */
- io_run_task_work();
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
io_uring_cancel_sqpoll(ctx);
sqd->thread = NULL;
list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
io_ring_set_wakeup_flag(ctx);
- up_write(&sqd->rw_lock);
+ mutex_unlock(&sqd->lock);
io_run_task_work();
+ io_run_task_work_head(&sqd->park_task_work);
complete(&sqd->exited);
do_exit(0);
}
@@ -7075,23 +7111,28 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
}
static void io_sq_thread_unpark(struct io_sq_data *sqd)
- __releases(&sqd->rw_lock)
+ __releases(&sqd->lock)
{
WARN_ON_ONCE(sqd->thread == current);
+ /*
+ * Do the dance but not conditional clear_bit() because it'd race with
+ * other threads incrementing park_pending and setting the bit.
+ */
clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
- up_write(&sqd->rw_lock);
+ if (atomic_dec_return(&sqd->park_pending))
+ set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
+ mutex_unlock(&sqd->lock);
}
static void io_sq_thread_park(struct io_sq_data *sqd)
- __acquires(&sqd->rw_lock)
+ __acquires(&sqd->lock)
{
WARN_ON_ONCE(sqd->thread == current);
+ atomic_inc(&sqd->park_pending);
set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
- down_write(&sqd->rw_lock);
- /* set again for consistency, in case concurrent parks are happening */
- set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
+ mutex_lock(&sqd->lock);
if (sqd->thread)
wake_up_process(sqd->thread);
}
@@ -7100,17 +7141,19 @@ static void io_sq_thread_stop(struct io_sq_data *sqd)
{
WARN_ON_ONCE(sqd->thread == current);
- down_write(&sqd->rw_lock);
+ mutex_lock(&sqd->lock);
set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
if (sqd->thread)
wake_up_process(sqd->thread);
- up_write(&sqd->rw_lock);
+ mutex_unlock(&sqd->lock);
wait_for_completion(&sqd->exited);
}
static void io_put_sq_data(struct io_sq_data *sqd)
{
if (refcount_dec_and_test(&sqd->refs)) {
+ WARN_ON_ONCE(atomic_read(&sqd->park_pending));
+
io_sq_thread_stop(sqd);
kfree(sqd);
}
@@ -7184,9 +7227,10 @@ static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
if (!sqd)
return ERR_PTR(-ENOMEM);
+ atomic_set(&sqd->park_pending, 0);
refcount_set(&sqd->refs, 1);
INIT_LIST_HEAD(&sqd->ctx_list);
- init_rwsem(&sqd->rw_lock);
+ mutex_init(&sqd->lock);
init_waitqueue_head(&sqd->wait);
init_completion(&sqd->exited);
return sqd;
@@ -7866,22 +7910,17 @@ static int io_sq_offload_create(struct io_ring_ctx *ctx,
ret = 0;
io_sq_thread_park(sqd);
+ list_add(&ctx->sqd_list, &sqd->ctx_list);
+ io_sqd_update_thread_idle(sqd);
/* don't attach to a dying SQPOLL thread, would be racy */
- if (attached && !sqd->thread) {
+ if (attached && !sqd->thread)
ret = -ENXIO;
- } else {
- list_add(&ctx->sqd_list, &sqd->ctx_list);
- io_sqd_update_thread_idle(sqd);
- }
io_sq_thread_unpark(sqd);
- if (ret < 0) {
- io_put_sq_data(sqd);
- ctx->sq_data = NULL;
- return ret;
- } else if (attached) {
+ if (ret < 0)
+ goto err;
+ if (attached)
return 0;
- }
if (p->flags & IORING_SETUP_SQ_AFF) {
int cpu = p->sq_thread_cpu;
@@ -8332,19 +8371,13 @@ static int io_eventfd_unregister(struct io_ring_ctx *ctx)
return -ENXIO;
}
-static int __io_destroy_buffers(int id, void *p, void *data)
-{
- struct io_ring_ctx *ctx = data;
- struct io_buffer *buf = p;
-
- __io_remove_buffers(ctx, buf, id, -1U);
- return 0;
-}
-
static void io_destroy_buffers(struct io_ring_ctx *ctx)
{
- idr_for_each(&ctx->io_buffer_idr, __io_destroy_buffers, ctx);
- idr_destroy(&ctx->io_buffer_idr);
+ struct io_buffer *buf;
+ unsigned long index;
+
+ xa_for_each(&ctx->io_buffers, index, buf)
+ __io_remove_buffers(ctx, buf, index, -1U);
}
static void io_req_cache_free(struct list_head *list, struct task_struct *tsk)
@@ -8386,11 +8419,13 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx)
{
/*
* Some may use context even when all refs and requests have been put,
- * and they are free to do so while still holding uring_lock, see
- * __io_req_task_submit(). Wait for them to finish.
+ * and they are free to do so while still holding uring_lock or
+ * completion_lock, see __io_req_task_submit(). Wait for them to finish.
*/
mutex_lock(&ctx->uring_lock);
mutex_unlock(&ctx->uring_lock);
+ spin_lock_irq(&ctx->completion_lock);
+ spin_unlock_irq(&ctx->completion_lock);
io_sq_thread_finish(ctx);
io_sqe_buffers_unregister(ctx);
@@ -8478,26 +8513,9 @@ static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
return -EINVAL;
}
-static bool io_run_ctx_fallback(struct io_ring_ctx *ctx)
+static inline bool io_run_ctx_fallback(struct io_ring_ctx *ctx)
{
- struct callback_head *work, *next;
- bool executed = false;
-
- do {
- work = xchg(&ctx->exit_task_work, NULL);
- if (!work)
- break;
-
- do {
- next = work->next;
- work->func(work);
- work = next;
- cond_resched();
- } while (work);
- executed = true;
- } while (1);
-
- return executed;
+ return io_run_task_work_head(&ctx->exit_task_work);
}
struct io_tctx_exit {
@@ -8580,6 +8598,14 @@ static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
io_unregister_personality(ctx, index);
mutex_unlock(&ctx->uring_lock);
+ /* prevent SQPOLL from submitting new requests */
+ if (ctx->sq_data) {
+ io_sq_thread_park(ctx->sq_data);
+ list_del_init(&ctx->sqd_list);
+ io_sqd_update_thread_idle(ctx->sq_data);
+ io_sq_thread_unpark(ctx->sq_data);
+ }
+
io_kill_timeouts(ctx, NULL, NULL);
io_poll_remove_all(ctx, NULL, NULL);
@@ -8879,7 +8905,7 @@ static void io_sqpoll_cancel_sync(struct io_ring_ctx *ctx)
if (task) {
init_completion(&work.completion);
init_task_work(&work.task_work, io_sqpoll_cancel_cb);
- WARN_ON_ONCE(task_work_add(task, &work.task_work, TWA_SIGNAL));
+ io_task_work_add_head(&sqd->park_task_work, &work.task_work);
wake_up_process(task);
}
io_sq_thread_unpark(sqd);
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 9761a0ec9f95..79cde9906be0 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -5,31 +5,6 @@
#include <linux/sched.h>
#include <linux/xarray.h>
-struct io_wq_work_node {
- struct io_wq_work_node *next;
-};
-
-struct io_wq_work_list {
- struct io_wq_work_node *first;
- struct io_wq_work_node *last;
-};
-
-struct io_uring_task {
- /* submission side */
- struct xarray xa;
- struct wait_queue_head wait;
- void *last;
- void *io_wq;
- struct percpu_counter inflight;
- atomic_t in_idle;
- bool sqpoll;
-
- spinlock_t task_lock;
- struct io_wq_work_list task_list;
- unsigned long task_state;
- struct callback_head task_work;
-};
-
#if defined(CONFIG_IO_URING)
struct sock *io_uring_get_socket(struct file *file);
void __io_uring_task_cancel(void);
diff --git a/kernel/fork.c b/kernel/fork.c
index 0acc8ed1076b..54cc905e5fe0 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -2444,7 +2444,6 @@ struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node)
if (!IS_ERR(tsk)) {
sigfillset(&tsk->blocked);
sigdelsetmask(&tsk->blocked, sigmask(SIGKILL));
- tsk->flags |= PF_NOFREEZE;
}
return tsk;
}
diff --git a/kernel/freezer.c b/kernel/freezer.c
index dc520f01f99d..1a2d57d1327c 100644
--- a/kernel/freezer.c
+++ b/kernel/freezer.c
@@ -134,7 +134,7 @@ bool freeze_task(struct task_struct *p)
return false;
}
- if (!(p->flags & PF_KTHREAD))
+ if (!(p->flags & (PF_KTHREAD | PF_IO_WORKER)))
fake_signal_wake_up(p);
else
wake_up_state(p, TASK_INTERRUPTIBLE);