4.19-stable patches

added patches:
	btrfs-limit-device-extents-to-the-device-size.patch

diff --git a/queue-4.19/btrfs-limit-device-extents-to-the-device-size.patch b/queue-4.19/btrfs-limit-device-extents-to-the-device-size.patch
new file mode 100644 (file)
index 0000000..e45c43c
--- /dev/null
+++ b/queue-4.19/btrfs-limit-device-extents-to-the-device-size.patch
@@ -0,0 +1,66 @@
+From 3c538de0f2a74d50aff7278c092f88ae59cee688 Mon Sep 17 00:00:00 2001
+From: Josef Bacik <josef@toxicpanda.com>
+Date: Wed, 18 Jan 2023 16:35:13 -0500
+Subject: btrfs: limit device extents to the device size
+
+From: Josef Bacik <josef@toxicpanda.com>
+
+commit 3c538de0f2a74d50aff7278c092f88ae59cee688 upstream.
+
+There was a recent regression in btrfs/177 that started happening with
+the size class patches ("btrfs: introduce size class to block group
+allocator").  This however isn't a regression introduced by those
+patches, but rather the bug was uncovered by a change in behavior in
+these patches.  The patches triggered more chunk allocations in the
+^free-space-tree case, which uncovered a race with device shrink.
+
+The problem is we will set the device total size to the new size, and
+use this to find a hole for a device extent.  However during shrink we
+may have device extents allocated past this range, so we could
+potentially find a hole in a range past our new shrink size.  We don't
+actually limit our found extent to the device size anywhere, we assume
+that we will not find a hole past our device size.  This isn't true with
+shrink as we're relocating block groups and thus creating holes past the
+device size.
+
+Fix this by making sure we do not search past the new device size, and
+if we wander into any device extents that start after our device size
+simply break from the loop and use whatever hole we've already found.
+
+CC: stable@vger.kernel.org # 4.14+
+Signed-off-by: Josef Bacik <josef@toxicpanda.com>
+Signed-off-by: David Sterba <dsterba@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/btrfs/volumes.c |    6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+--- a/fs/btrfs/volumes.c
++++ b/fs/btrfs/volumes.c
+@@ -1418,7 +1418,7 @@ again:
+                       goto out;
+       }
+ 
+-      while (1) {
++      while (search_start < search_end) {
+               l = path->nodes[0];
+               slot = path->slots[0];
+               if (slot >= btrfs_header_nritems(l)) {
+@@ -1441,6 +1441,9 @@ again:
+               if (key.type != BTRFS_DEV_EXTENT_KEY)
+                       goto next;
+ 
++              if (key.offset > search_end)
++                      break;
++
+               if (key.offset > search_start) {
+                       hole_size = key.offset - search_start;
+ 
+@@ -1515,6 +1518,7 @@ next:
+       else
+               ret = 0;
+ 
++      ASSERT(max_hole_start + max_hole_size <= search_end);
+ out:
+       btrfs_free_path(path);
+       *start = max_hole_start;

diff --git a/queue-4.19/series b/queue-4.19/series
index 861f394f486ab8b0b2536bf168da96781304a8cd..66818a4e5912ea49ff9ebeab13348c3c42026cad 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -40,3 +40,4 @@ serial-8250_dma-fix-dma-rx-completion-race.patch
 serial-8250_dma-fix-dma-rx-rearm-race.patch
 thermal-intel-int340x-add-locking-to-int340x_thermal_get_trip_type.patch
 iio-adc-twl6030-enable-measurement-of-vac.patch
+btrfs-limit-device-extents-to-the-device-size.patch