Commit 1324bb78 authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Yang Yingliang
Browse files

async: Introduce async_schedule_dev_nocall() 

stable inclusion
from stable-v5.10.210
commit ac4dcccbe9106a5cec483d2ffa7f628b95340a07
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I97NIA
CVE: CVE-2023-52498

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ac4dcccbe9106a5cec483d2ffa7f628b95340a07



--------------------------------

commit 7d4b5d7a37bdd63a5a3371b988744b060d5bb86f upstream.

In preparation for subsequent changes, introduce a specialized variant
of async_schedule_dev() that will not invoke the argument function
synchronously when it cannot be scheduled for asynchronous execution.

The new function, async_schedule_dev_nocall(), will be used for fixing
possible deadlocks in the system-wide power management core code.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com> for the series.
Tested-by: default avatarYoungmin Nam <youngmin.nam@samsung.com>
Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
parent c2c1551c

include/linux/async.h

+2 −0
Original line number Diff line number Diff line
@@ -90,6 +90,8 @@ async_schedule_dev(async_func_t func, struct device *dev) 
	return async_schedule_node(func, dev, dev_to_node(dev));

}



bool async_schedule_dev_nocall(async_func_t func, struct device *dev);



/**

 * async_schedule_dev_domain - A device specific version of async_schedule_domain

 * @func: function to execute asynchronously

kernel/async.c

+29 −0
Original line number Diff line number Diff line
@@ -243,6 +243,35 @@ async_cookie_t async_schedule_node(async_func_t func, void *data, int node) 
}

EXPORT_SYMBOL_GPL(async_schedule_node);



/**

 * async_schedule_dev_nocall - A simplified variant of async_schedule_dev()

 * @func: function to execute asynchronously

 * @dev: device argument to be passed to function

 *

 * @dev is used as both the argument for the function and to provide NUMA

 * context for where to run the function.

 *

 * If the asynchronous execution of @func is scheduled successfully, return

 * true. Otherwise, do nothing and return false, unlike async_schedule_dev()

 * that will run the function synchronously then.

 */

bool async_schedule_dev_nocall(async_func_t func, struct device *dev)

{

	struct async_entry *entry;



	entry = kzalloc(sizeof(struct async_entry), GFP_KERNEL);



	/* Give up if there is no memory or too much work. */

	if (!entry || atomic_read(&entry_count) > MAX_WORK) {

		kfree(entry);

		return false;

	}



	__async_schedule_node_domain(func, dev, dev_to_node(dev),

				     &async_dfl_domain, entry);

	return true;

}



/**

 * async_synchronize_full - synchronize all asynchronous function calls

 *