Re: [Drbd-dev] DRBD8: Stuck in WFBitMapS state even across reboot.

[Philipp Reisner <philipp.reisner@linbit.com>]

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[...]

Lars, that's right, this is the reason for the race condition. 
I think this patch fixes this. With this patch it should no longer
be possible to get both nodes into the WFBitMaps state.

It is in SVN with revision 2607.

Ernest, could you repeat your tests with this revision? Thanks!

-Phil
-- 
: Dipl-Ing Philipp Reisner                      Tel +43-1-8178292-50 :
: LINBIT Information Technologies GmbH          Fax +43-1-8178292-82 :
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Index: drbd_receiver.c
===================================================================
--- drbd_receiver.c	(revision 2603)
+++ drbd_receiver.c	(working copy)
@@ -1668,7 +1668,7 @@
 	peer = mdev->p_uuid[Bitmap] & 1;
 
 	ch_peer = mdev->p_uuid[UUID_SIZE];
-	ch_self = drbd_bm_total_weight(mdev);
+	ch_self = mdev->comm_bm_set;
 
 	switch ( mdev->net_conf->after_sb_0p ) {
 	case Consensus:
Index: drbd_main.c
===================================================================
--- drbd_main.c	(revision 2603)
+++ drbd_main.c	(working copy)
@@ -1288,7 +1288,8 @@
 			: 0;
 	}
 
-	p.uuid[UUID_SIZE] = cpu_to_be64(drbd_bm_total_weight(mdev));
+	mdev->comm_bm_set = drbd_bm_total_weight(mdev);
+	p.uuid[UUID_SIZE] = cpu_to_be64(mdev->comm_bm_set);
 	uuid_flags |= mdev->net_conf->want_lose ? 1 : 0;
 	uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
 	p.uuid[UUID_FLAGS] = cpu_to_be64(uuid_flags);
Index: drbd_int.h
===================================================================
--- drbd_int.h	(revision 2603)
+++ drbd_int.h	(working copy)
@@ -853,6 +853,7 @@
 	unsigned int peer_seq;
 	spinlock_t peer_seq_lock;
 	int minor;
+	unsigned long comm_bm_set; // communicated number of set bits.
 };
 
 static inline drbd_dev *minor_to_mdev(int minor)