linux-kernel - [PATCH v1] fs: Prevent spurious wakeups with TASK

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <20250725030341.520-1-daijunbing@vivo.com>
Date: Fri, 25 Jul 2025 11:03:39 +0800
From: Dai Junbing <daijunbing@...o.com>
To: Alexander Viro <viro@...iv.linux.org.uk>,
	Christian Brauner <brauner@...nel.org>,
	Jan Kara <jack@...e.cz>,
	Miklos Szeredi <miklos@...redi.hu>,
	"Theodore Ts'o" <tytso@....edu>,
	linux-fsdevel@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-ext4@...r.kernel.org
Cc: opensource.kernel@...o.com,
	junbing dai <daijunbing@...o.com>
Subject: [PATCH v1] fs: Prevent spurious wakeups with TASK_FREEZABLE

From: junbing dai <daijunbing@...o.com>

During system suspend, processes in TASK_INTERRUPTIBLE state get
forcibly awakened. By applying TASK_FREEZABLE flag, we prevent these
unnecessary wakeups and reduce suspend/resume overhead

Signed-off-by: junbing dai <daijunbing@...o.com>
---
 fs/eventpoll.c    | 2 +-
 fs/fuse/dev.c     | 2 +-
 fs/jbd2/journal.c | 2 +-
 fs/pipe.c         | 4 ++--
 fs/select.c       | 4 ++--
 5 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 0fbf5dfedb24..6020575bdbab 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -2094,7 +2094,7 @@ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
 		 * the same lock on wakeup ep_poll_callback() side, so it
 		 * is safe to avoid an explicit barrier.
 		 */
-		__set_current_state(TASK_INTERRUPTIBLE);
+		__set_current_state(TASK_INTERRUPTIBLE|TASK_FREEZABLE);
 
 		/*
 		 * Do the final check under the lock. ep_start/done_scan()
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c
index e80cd8f2c049..b3dbd113e2e2 100644
--- a/fs/fuse/dev.c
+++ b/fs/fuse/dev.c
@@ -1418,7 +1418,7 @@ static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
 
 		if (file->f_flags & O_NONBLOCK)
 			return -EAGAIN;
-		err = wait_event_interruptible_exclusive(fiq->waitq,
+		err = wait_event_freezable_exclusive(fiq->waitq,
 				!fiq->connected || request_pending(fiq));
 		if (err)
 			return err;
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index d480b94117cd..a6ca1468ccfe 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -222,7 +222,7 @@ static int kjournald2(void *arg)
 		DEFINE_WAIT(wait);
 
 		prepare_to_wait(&journal->j_wait_commit, &wait,
-				TASK_INTERRUPTIBLE);
+				TASK_INTERRUPTIBLE|TASK_FREEZABLE);
 		transaction = journal->j_running_transaction;
 		if (transaction == NULL ||
 		    time_before(jiffies, transaction->t_expires)) {
diff --git a/fs/pipe.c b/fs/pipe.c
index 45077c37bad1..a0e624fc734c 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -385,7 +385,7 @@ anon_pipe_read(struct kiocb *iocb, struct iov_iter *to)
 		 * since we've done any required wakeups and there's no need
 		 * to mark anything accessed. And we've dropped the lock.
 		 */
-		if (wait_event_interruptible_exclusive(pipe->rd_wait, pipe_readable(pipe)) < 0)
+		if (wait_event_freezable_exclusive(pipe->rd_wait, pipe_readable(pipe)) < 0)
 			return -ERESTARTSYS;
 
 		wake_next_reader = true;
@@ -1098,7 +1098,7 @@ static int wait_for_partner(struct pipe_inode_info *pipe, unsigned int *cnt)
 	int cur = *cnt;
 
 	while (cur == *cnt) {
-		prepare_to_wait(&pipe->rd_wait, &rdwait, TASK_INTERRUPTIBLE);
+		prepare_to_wait(&pipe->rd_wait, &rdwait, TASK_INTERRUPTIBLE|TASK_FREEZABLE);
 		pipe_unlock(pipe);
 		schedule();
 		finish_wait(&pipe->rd_wait, &rdwait);
diff --git a/fs/select.c b/fs/select.c
index 9fb650d03d52..0903a08b8067 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -600,7 +600,7 @@ static noinline_for_stack int do_select(int n, fd_set_bits *fds, struct timespec
 			to = &expire;
 		}
 
-		if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE,
+		if (!poll_schedule_timeout(&table, TASK_INTERRUPTIBLE|TASK_FREEZABLE,
 					   to, slack))
 			timed_out = 1;
 	}
@@ -955,7 +955,7 @@ static int do_poll(struct poll_list *list, struct poll_wqueues *wait,
 			to = &expire;
 		}
 
-		if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE, to, slack))
+		if (!poll_schedule_timeout(wait, TASK_INTERRUPTIBLE|TASK_FREEZABLE, to, slack))
 			timed_out = 1;
 	}
 	return count;
-- 
2.25.1