1 files changed, 100 insertions, 0 deletions

diff --git a/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.6/0029-PM-Hibernate-Fix-s2disk-regression-related-to-freezi.patch b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.6/0029-PM-Hibernate-Fix-s2disk-regression-related-to-freezi.patch
new file mode 100644
index 00000000..524e6d1d
--- /dev/null
+++ b/recipes-kernel/linux/linux-ti33x-psp-3.2/3.2.6/0029-PM-Hibernate-Fix-s2disk-regression-related-to-freezi.patch
@@ -0,0 +1,100 @@
+From d483054fe4c66eeb7a03fdc97519b07edb1dc803 Mon Sep 17 00:00:00 2001
+From: "Rafael J. Wysocki" <rjw@sisk.pl>
+Date: Sun, 29 Jan 2012 20:35:52 +0100
+Subject: [PATCH 29/87] PM / Hibernate: Fix s2disk regression related to
+ freezing workqueues
+
+commit 181e9bdef37bfcaa41f3ab6c948a2a0d60a268b5 upstream.
+
+Commit 2aede851ddf08666f68ffc17be446420e9d2a056
+
+  PM / Hibernate: Freeze kernel threads after preallocating memory
+
+introduced a mechanism by which kernel threads were frozen after
+the preallocation of hibernate image memory to avoid problems with
+frozen kernel threads not responding to memory freeing requests.
+However, it overlooked the s2disk code path in which the
+SNAPSHOT_CREATE_IMAGE ioctl was run directly after SNAPSHOT_FREE,
+which caused freeze_workqueues_begin() to BUG(), because it saw
+that worqueues had been already frozen.
+
+Although in principle this issue might be addressed by removing
+the relevant BUG_ON() from freeze_workqueues_begin(), that would
+reintroduce the very problem that commit 2aede851ddf08666f68ffc17be4
+attempted to avoid into that particular code path.  For this reason,
+to fix the issue at hand, introduce thaw_kernel_threads() and make
+the SNAPSHOT_FREE ioctl execute it.
+
+Special thanks to Srivatsa S. Bhat for detailed analysis of the
+problem.
+
+Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz>
+Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
+Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/freezer.h |    2 ++
+ kernel/power/process.c  |    9 +++++++++
+ kernel/power/user.c     |    9 +++++++++
+ 3 files changed, 20 insertions(+), 0 deletions(-)
+
+diff --git a/include/linux/freezer.h b/include/linux/freezer.h
+index a5386e3..b5d6b6a 100644
+--- a/include/linux/freezer.h
++++ b/include/linux/freezer.h
+@@ -51,6 +51,7 @@ extern void refrigerator(void);
+ extern int freeze_processes(void);
+ extern int freeze_kernel_threads(void);
+ extern void thaw_processes(void);
++extern void thaw_kernel_threads(void);
+ 
+ static inline int try_to_freeze(void)
+ {
+@@ -185,6 +186,7 @@ static inline void refrigerator(void) {}
+ static inline int freeze_processes(void) { return -ENOSYS; }
+ static inline int freeze_kernel_threads(void) { return -ENOSYS; }
+ static inline void thaw_processes(void) {}
++static inline void thaw_kernel_threads(void) {}
+ 
+ static inline int try_to_freeze(void) { return 0; }
+ 
+diff --git a/kernel/power/process.c b/kernel/power/process.c
+index addbbe5..3d4b954 100644
+--- a/kernel/power/process.c
++++ b/kernel/power/process.c
+@@ -203,3 +203,12 @@ void thaw_processes(void)
+        printk("done.\n");
+ }
+ 
++void thaw_kernel_threads(void)
++{
++       printk("Restarting kernel threads ... ");
++       thaw_workqueues();
++       thaw_tasks(true);
++       schedule();
++       printk("done.\n");
++}
++
+diff --git a/kernel/power/user.c b/kernel/power/user.c
+index 6d8f535..3565b15 100644
+--- a/kernel/power/user.c
++++ b/kernel/power/user.c
+@@ -303,6 +303,15 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+                swsusp_free();
+                memset(&data->handle, 0, sizeof(struct snapshot_handle));
+                data->ready = 0;
++               /*
++                * It is necessary to thaw kernel threads here, because
++                * SNAPSHOT_CREATE_IMAGE may be invoked directly after
++                * SNAPSHOT_FREE.  In that case, if kernel threads were not
++                * thawed, the preallocation of memory carried out by
++                * hibernation_snapshot() might run into problems (i.e. it
++                * might fail or even deadlock).
++                */
++               thaw_kernel_threads();
+                break;
+ 
+        case SNAPSHOT_SET_IMAGE_SIZE:
+-- 
+1.7.7.4
+