[RFC][PATCH -mm 3/3] freezer: Fix problem with kthread_stop

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Rafael J. Wysocki <[email protected]>

Fix the problem with kthread_stop() that causes the freezer to fail if a
freezable thread is attempting to stop a frozen one and that may cause the
freezer to fail if the thread being stopped is freezable and
try_to_freeze_tasks() is running concurrently with kthread_stop().

Signed-off-by: Rafael J. Wysocki <[email protected]>
---
 kernel/kthread.c |    9 +++++++++
 1 file changed, 9 insertions(+)

Index: linux-2.6.21-rc6-mm1/kernel/kthread.c
===================================================================
--- linux-2.6.21-rc6-mm1.orig/kernel/kthread.c	2007-04-09 15:23:48.000000000 +0200
+++ linux-2.6.21-rc6-mm1/kernel/kthread.c	2007-04-22 19:05:29.000000000 +0200
@@ -13,6 +13,7 @@
 #include <linux/file.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/freezer.h>
 #include <asm/semaphore.h>
 
 /*
@@ -232,6 +233,14 @@ int kthread_stop(struct task_struct *k)
 
 	/* Now set kthread_should_stop() to true, and wake it up. */
 	kthread_stop_info.k = k;
+	if (!freezer_should_exempt(current)) {
+		/* We are freezable, so we must make sure that the thread being
+		 * stopped is not frozen and will not be frozen until it dies
+		 */
+		freezer_exempt(k);
+		if (frozen(k))
+			clear_frozen_flag(k);
+	}
 	wake_up_process(k);
 	put_task_struct(k);
 
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux