max_register is currently set to 0x1000. This is beyond the mapped
address range of the hardware, so attempts to dump the regmap from
debugfs would trigger a kernel exception.
Furthermore, the useful registers only occupy a small section at the
beginning of the full range. Change the value to 0x9c, the last known
register on the V3s and H3.
On the A31, the register range is extended to support additional
capture channels. Since this is not yet supported, ignore it for now.
Fixes: 5cc7522d8965 ("media: sun6i: Add support for Allwinner CSI V3s")
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Chen-Yu Tsai <wens(a)csie.org>
---
drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
index ee882b66a5ea..332cf81a7ecf 100644
--- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
+++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
@@ -793,7 +793,7 @@ static const struct regmap_config sun6i_csi_regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
- .max_register = 0x1000,
+ .max_register = 0x9c,
};
static int sun6i_csi_resource_request(struct sun6i_csi_dev *sdev,
--
2.20.1
The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From a6279470762c19ba97e454f90798373dccdf6148 Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Fri, 25 Jan 2019 11:48:51 +0000
Subject: [PATCH] Btrfs: fix deadlock when allocating tree block during
leaf/node split
When splitting a leaf or node from one of the trees that are modified when
flushing pending block groups (extent, chunk, device and free space trees),
we need to allocate a new tree block, which in turn can result in the need
to allocate a new block group. After allocating the new block group we may
need to flush new block groups that were previously allocated during the
course of the current transaction, which is what may cause a deadlock due
to attempts to write lock twice the same leaf or node, as when splitting
a leaf or node we are holding a write lock on it and its parent node.
The same type of deadlock can also happen when increasing the tree's
height, since we are holding a lock on the existing root while allocating
the tree block to use as the new root node.
An example trace when the deadlock happens during the leaf split path is:
[27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G W 4.19.16 #1
[27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018
[27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
(...)
[27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246
[27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001
[27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48
[27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000
[27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000
[27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18
[27175.303601] FS: 0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000
[27175.304468] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0
[27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[27175.307940] Call Trace:
[27175.308802] btrfs_search_slot+0x779/0x9a0 [btrfs]
[27175.309669] ? update_space_info+0xba/0xe0 [btrfs]
[27175.310534] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.311397] btrfs_insert_item+0x60/0xd0 [btrfs]
[27175.312253] btrfs_create_pending_block_groups+0xee/0x210 [btrfs]
[27175.313116] do_chunk_alloc+0x25f/0x300 [btrfs]
[27175.313984] find_free_extent+0x706/0x10d0 [btrfs]
[27175.314855] btrfs_reserve_extent+0x9b/0x1d0 [btrfs]
[27175.315707] btrfs_alloc_tree_block+0x100/0x5b0 [btrfs]
[27175.316548] split_leaf+0x130/0x610 [btrfs]
[27175.317390] btrfs_search_slot+0x94d/0x9a0 [btrfs]
[27175.318235] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.319087] alloc_reserved_file_extent+0x84/0x2c0 [btrfs]
[27175.319938] __btrfs_run_delayed_refs+0x596/0x1150 [btrfs]
[27175.320792] btrfs_run_delayed_refs+0xed/0x1b0 [btrfs]
[27175.321643] delayed_ref_async_start+0x81/0x90 [btrfs]
[27175.322491] normal_work_helper+0xd0/0x320 [btrfs]
[27175.323328] ? move_linked_works+0x6e/0xa0
[27175.324160] process_one_work+0x191/0x370
[27175.324976] worker_thread+0x4f/0x3b0
[27175.325763] kthread+0xf8/0x130
[27175.326531] ? rescuer_thread+0x320/0x320
[27175.327284] ? kthread_create_worker_on_cpu+0x50/0x50
[27175.328027] ret_from_fork+0x35/0x40
[27175.328741] ---[ end trace 300a1b9f0ac30e26 ]---
Fix this by preventing the flushing of new blocks groups when splitting a
leaf/node and when inserting a new root node for one of the trees modified
by the flushing operation, similar to what is done when COWing a node/leaf
from on of these trees.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383
Reported-by: Eli V <eliventer(a)gmail.com>
CC: stable(a)vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f64aad613727..5a6c39b44c84 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -968,6 +968,48 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
return 0;
}
+static struct extent_buffer *alloc_tree_block_no_bg_flush(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 parent_start,
+ const struct btrfs_disk_key *disk_key,
+ int level,
+ u64 hint,
+ u64 empty_size)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct extent_buffer *ret;
+
+ /*
+ * If we are COWing a node/leaf from the extent, chunk, device or free
+ * space trees, make sure that we do not finish block group creation of
+ * pending block groups. We do this to avoid a deadlock.
+ * COWing can result in allocation of a new chunk, and flushing pending
+ * block groups (btrfs_create_pending_block_groups()) can be triggered
+ * when finishing allocation of a new chunk. Creation of a pending block
+ * group modifies the extent, chunk, device and free space trees,
+ * therefore we could deadlock with ourselves since we are holding a
+ * lock on an extent buffer that btrfs_create_pending_block_groups() may
+ * try to COW later.
+ * For similar reasons, we also need to delay flushing pending block
+ * groups when splitting a leaf or node, from one of those trees, since
+ * we are holding a write lock on it and its parent or when inserting a
+ * new root node for one of those trees.
+ */
+ if (root == fs_info->extent_root ||
+ root == fs_info->chunk_root ||
+ root == fs_info->dev_root ||
+ root == fs_info->free_space_root)
+ trans->can_flush_pending_bgs = false;
+
+ ret = btrfs_alloc_tree_block(trans, root, parent_start,
+ root->root_key.objectid, disk_key, level,
+ hint, empty_size);
+ trans->can_flush_pending_bgs = true;
+
+ return ret;
+}
+
/*
* does the dirty work in cow of a single block. The parent block (if
* supplied) is updated to point to the new cow copy. The new buffer is marked
@@ -1015,28 +1057,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
if ((root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && parent)
parent_start = parent->start;
- /*
- * If we are COWing a node/leaf from the extent, chunk, device or free
- * space trees, make sure that we do not finish block group creation of
- * pending block groups. We do this to avoid a deadlock.
- * COWing can result in allocation of a new chunk, and flushing pending
- * block groups (btrfs_create_pending_block_groups()) can be triggered
- * when finishing allocation of a new chunk. Creation of a pending block
- * group modifies the extent, chunk, device and free space trees,
- * therefore we could deadlock with ourselves since we are holding a
- * lock on an extent buffer that btrfs_create_pending_block_groups() may
- * try to COW later.
- */
- if (root == fs_info->extent_root ||
- root == fs_info->chunk_root ||
- root == fs_info->dev_root ||
- root == fs_info->free_space_root)
- trans->can_flush_pending_bgs = false;
-
- cow = btrfs_alloc_tree_block(trans, root, parent_start,
- root->root_key.objectid, &disk_key, level,
- search_start, empty_size);
- trans->can_flush_pending_bgs = true;
+ cow = alloc_tree_block_no_bg_flush(trans, root, parent_start, &disk_key,
+ level, search_start, empty_size);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -3345,8 +3367,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
else
btrfs_node_key(lower, &lower_key, 0);
- c = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &lower_key, level, root->node->start, 0);
+ c = alloc_tree_block_no_bg_flush(trans, root, 0, &lower_key, level,
+ root->node->start, 0);
if (IS_ERR(c))
return PTR_ERR(c);
@@ -3475,8 +3497,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
mid = (c_nritems + 1) / 2;
btrfs_node_key(c, &disk_key, mid);
- split = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, level, c->start, 0);
+ split = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, level,
+ c->start, 0);
if (IS_ERR(split))
return PTR_ERR(split);
@@ -4260,8 +4282,8 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
else
btrfs_item_key(l, &disk_key, mid);
- right = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, 0, l->start, 0);
+ right = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, 0,
+ l->start, 0);
if (IS_ERR(right))
return PTR_ERR(right);
The patch below does not apply to the 4.9-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From a6279470762c19ba97e454f90798373dccdf6148 Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Fri, 25 Jan 2019 11:48:51 +0000
Subject: [PATCH] Btrfs: fix deadlock when allocating tree block during
leaf/node split
When splitting a leaf or node from one of the trees that are modified when
flushing pending block groups (extent, chunk, device and free space trees),
we need to allocate a new tree block, which in turn can result in the need
to allocate a new block group. After allocating the new block group we may
need to flush new block groups that were previously allocated during the
course of the current transaction, which is what may cause a deadlock due
to attempts to write lock twice the same leaf or node, as when splitting
a leaf or node we are holding a write lock on it and its parent node.
The same type of deadlock can also happen when increasing the tree's
height, since we are holding a lock on the existing root while allocating
the tree block to use as the new root node.
An example trace when the deadlock happens during the leaf split path is:
[27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G W 4.19.16 #1
[27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018
[27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
(...)
[27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246
[27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001
[27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48
[27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000
[27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000
[27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18
[27175.303601] FS: 0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000
[27175.304468] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0
[27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[27175.307940] Call Trace:
[27175.308802] btrfs_search_slot+0x779/0x9a0 [btrfs]
[27175.309669] ? update_space_info+0xba/0xe0 [btrfs]
[27175.310534] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.311397] btrfs_insert_item+0x60/0xd0 [btrfs]
[27175.312253] btrfs_create_pending_block_groups+0xee/0x210 [btrfs]
[27175.313116] do_chunk_alloc+0x25f/0x300 [btrfs]
[27175.313984] find_free_extent+0x706/0x10d0 [btrfs]
[27175.314855] btrfs_reserve_extent+0x9b/0x1d0 [btrfs]
[27175.315707] btrfs_alloc_tree_block+0x100/0x5b0 [btrfs]
[27175.316548] split_leaf+0x130/0x610 [btrfs]
[27175.317390] btrfs_search_slot+0x94d/0x9a0 [btrfs]
[27175.318235] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.319087] alloc_reserved_file_extent+0x84/0x2c0 [btrfs]
[27175.319938] __btrfs_run_delayed_refs+0x596/0x1150 [btrfs]
[27175.320792] btrfs_run_delayed_refs+0xed/0x1b0 [btrfs]
[27175.321643] delayed_ref_async_start+0x81/0x90 [btrfs]
[27175.322491] normal_work_helper+0xd0/0x320 [btrfs]
[27175.323328] ? move_linked_works+0x6e/0xa0
[27175.324160] process_one_work+0x191/0x370
[27175.324976] worker_thread+0x4f/0x3b0
[27175.325763] kthread+0xf8/0x130
[27175.326531] ? rescuer_thread+0x320/0x320
[27175.327284] ? kthread_create_worker_on_cpu+0x50/0x50
[27175.328027] ret_from_fork+0x35/0x40
[27175.328741] ---[ end trace 300a1b9f0ac30e26 ]---
Fix this by preventing the flushing of new blocks groups when splitting a
leaf/node and when inserting a new root node for one of the trees modified
by the flushing operation, similar to what is done when COWing a node/leaf
from on of these trees.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383
Reported-by: Eli V <eliventer(a)gmail.com>
CC: stable(a)vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f64aad613727..5a6c39b44c84 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -968,6 +968,48 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
return 0;
}
+static struct extent_buffer *alloc_tree_block_no_bg_flush(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 parent_start,
+ const struct btrfs_disk_key *disk_key,
+ int level,
+ u64 hint,
+ u64 empty_size)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct extent_buffer *ret;
+
+ /*
+ * If we are COWing a node/leaf from the extent, chunk, device or free
+ * space trees, make sure that we do not finish block group creation of
+ * pending block groups. We do this to avoid a deadlock.
+ * COWing can result in allocation of a new chunk, and flushing pending
+ * block groups (btrfs_create_pending_block_groups()) can be triggered
+ * when finishing allocation of a new chunk. Creation of a pending block
+ * group modifies the extent, chunk, device and free space trees,
+ * therefore we could deadlock with ourselves since we are holding a
+ * lock on an extent buffer that btrfs_create_pending_block_groups() may
+ * try to COW later.
+ * For similar reasons, we also need to delay flushing pending block
+ * groups when splitting a leaf or node, from one of those trees, since
+ * we are holding a write lock on it and its parent or when inserting a
+ * new root node for one of those trees.
+ */
+ if (root == fs_info->extent_root ||
+ root == fs_info->chunk_root ||
+ root == fs_info->dev_root ||
+ root == fs_info->free_space_root)
+ trans->can_flush_pending_bgs = false;
+
+ ret = btrfs_alloc_tree_block(trans, root, parent_start,
+ root->root_key.objectid, disk_key, level,
+ hint, empty_size);
+ trans->can_flush_pending_bgs = true;
+
+ return ret;
+}
+
/*
* does the dirty work in cow of a single block. The parent block (if
* supplied) is updated to point to the new cow copy. The new buffer is marked
@@ -1015,28 +1057,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
if ((root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && parent)
parent_start = parent->start;
- /*
- * If we are COWing a node/leaf from the extent, chunk, device or free
- * space trees, make sure that we do not finish block group creation of
- * pending block groups. We do this to avoid a deadlock.
- * COWing can result in allocation of a new chunk, and flushing pending
- * block groups (btrfs_create_pending_block_groups()) can be triggered
- * when finishing allocation of a new chunk. Creation of a pending block
- * group modifies the extent, chunk, device and free space trees,
- * therefore we could deadlock with ourselves since we are holding a
- * lock on an extent buffer that btrfs_create_pending_block_groups() may
- * try to COW later.
- */
- if (root == fs_info->extent_root ||
- root == fs_info->chunk_root ||
- root == fs_info->dev_root ||
- root == fs_info->free_space_root)
- trans->can_flush_pending_bgs = false;
-
- cow = btrfs_alloc_tree_block(trans, root, parent_start,
- root->root_key.objectid, &disk_key, level,
- search_start, empty_size);
- trans->can_flush_pending_bgs = true;
+ cow = alloc_tree_block_no_bg_flush(trans, root, parent_start, &disk_key,
+ level, search_start, empty_size);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -3345,8 +3367,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
else
btrfs_node_key(lower, &lower_key, 0);
- c = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &lower_key, level, root->node->start, 0);
+ c = alloc_tree_block_no_bg_flush(trans, root, 0, &lower_key, level,
+ root->node->start, 0);
if (IS_ERR(c))
return PTR_ERR(c);
@@ -3475,8 +3497,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
mid = (c_nritems + 1) / 2;
btrfs_node_key(c, &disk_key, mid);
- split = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, level, c->start, 0);
+ split = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, level,
+ c->start, 0);
if (IS_ERR(split))
return PTR_ERR(split);
@@ -4260,8 +4282,8 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
else
btrfs_item_key(l, &disk_key, mid);
- right = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, 0, l->start, 0);
+ right = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, 0,
+ l->start, 0);
if (IS_ERR(right))
return PTR_ERR(right);
The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From a6279470762c19ba97e454f90798373dccdf6148 Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Fri, 25 Jan 2019 11:48:51 +0000
Subject: [PATCH] Btrfs: fix deadlock when allocating tree block during
leaf/node split
When splitting a leaf or node from one of the trees that are modified when
flushing pending block groups (extent, chunk, device and free space trees),
we need to allocate a new tree block, which in turn can result in the need
to allocate a new block group. After allocating the new block group we may
need to flush new block groups that were previously allocated during the
course of the current transaction, which is what may cause a deadlock due
to attempts to write lock twice the same leaf or node, as when splitting
a leaf or node we are holding a write lock on it and its parent node.
The same type of deadlock can also happen when increasing the tree's
height, since we are holding a lock on the existing root while allocating
the tree block to use as the new root node.
An example trace when the deadlock happens during the leaf split path is:
[27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G W 4.19.16 #1
[27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018
[27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
(...)
[27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246
[27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001
[27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48
[27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000
[27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000
[27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18
[27175.303601] FS: 0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000
[27175.304468] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0
[27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[27175.307940] Call Trace:
[27175.308802] btrfs_search_slot+0x779/0x9a0 [btrfs]
[27175.309669] ? update_space_info+0xba/0xe0 [btrfs]
[27175.310534] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.311397] btrfs_insert_item+0x60/0xd0 [btrfs]
[27175.312253] btrfs_create_pending_block_groups+0xee/0x210 [btrfs]
[27175.313116] do_chunk_alloc+0x25f/0x300 [btrfs]
[27175.313984] find_free_extent+0x706/0x10d0 [btrfs]
[27175.314855] btrfs_reserve_extent+0x9b/0x1d0 [btrfs]
[27175.315707] btrfs_alloc_tree_block+0x100/0x5b0 [btrfs]
[27175.316548] split_leaf+0x130/0x610 [btrfs]
[27175.317390] btrfs_search_slot+0x94d/0x9a0 [btrfs]
[27175.318235] btrfs_insert_empty_items+0x67/0xc0 [btrfs]
[27175.319087] alloc_reserved_file_extent+0x84/0x2c0 [btrfs]
[27175.319938] __btrfs_run_delayed_refs+0x596/0x1150 [btrfs]
[27175.320792] btrfs_run_delayed_refs+0xed/0x1b0 [btrfs]
[27175.321643] delayed_ref_async_start+0x81/0x90 [btrfs]
[27175.322491] normal_work_helper+0xd0/0x320 [btrfs]
[27175.323328] ? move_linked_works+0x6e/0xa0
[27175.324160] process_one_work+0x191/0x370
[27175.324976] worker_thread+0x4f/0x3b0
[27175.325763] kthread+0xf8/0x130
[27175.326531] ? rescuer_thread+0x320/0x320
[27175.327284] ? kthread_create_worker_on_cpu+0x50/0x50
[27175.328027] ret_from_fork+0x35/0x40
[27175.328741] ---[ end trace 300a1b9f0ac30e26 ]---
Fix this by preventing the flushing of new blocks groups when splitting a
leaf/node and when inserting a new root node for one of the trees modified
by the flushing operation, similar to what is done when COWing a node/leaf
from on of these trees.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383
Reported-by: Eli V <eliventer(a)gmail.com>
CC: stable(a)vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index f64aad613727..5a6c39b44c84 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -968,6 +968,48 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
return 0;
}
+static struct extent_buffer *alloc_tree_block_no_bg_flush(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 parent_start,
+ const struct btrfs_disk_key *disk_key,
+ int level,
+ u64 hint,
+ u64 empty_size)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct extent_buffer *ret;
+
+ /*
+ * If we are COWing a node/leaf from the extent, chunk, device or free
+ * space trees, make sure that we do not finish block group creation of
+ * pending block groups. We do this to avoid a deadlock.
+ * COWing can result in allocation of a new chunk, and flushing pending
+ * block groups (btrfs_create_pending_block_groups()) can be triggered
+ * when finishing allocation of a new chunk. Creation of a pending block
+ * group modifies the extent, chunk, device and free space trees,
+ * therefore we could deadlock with ourselves since we are holding a
+ * lock on an extent buffer that btrfs_create_pending_block_groups() may
+ * try to COW later.
+ * For similar reasons, we also need to delay flushing pending block
+ * groups when splitting a leaf or node, from one of those trees, since
+ * we are holding a write lock on it and its parent or when inserting a
+ * new root node for one of those trees.
+ */
+ if (root == fs_info->extent_root ||
+ root == fs_info->chunk_root ||
+ root == fs_info->dev_root ||
+ root == fs_info->free_space_root)
+ trans->can_flush_pending_bgs = false;
+
+ ret = btrfs_alloc_tree_block(trans, root, parent_start,
+ root->root_key.objectid, disk_key, level,
+ hint, empty_size);
+ trans->can_flush_pending_bgs = true;
+
+ return ret;
+}
+
/*
* does the dirty work in cow of a single block. The parent block (if
* supplied) is updated to point to the new cow copy. The new buffer is marked
@@ -1015,28 +1057,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
if ((root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) && parent)
parent_start = parent->start;
- /*
- * If we are COWing a node/leaf from the extent, chunk, device or free
- * space trees, make sure that we do not finish block group creation of
- * pending block groups. We do this to avoid a deadlock.
- * COWing can result in allocation of a new chunk, and flushing pending
- * block groups (btrfs_create_pending_block_groups()) can be triggered
- * when finishing allocation of a new chunk. Creation of a pending block
- * group modifies the extent, chunk, device and free space trees,
- * therefore we could deadlock with ourselves since we are holding a
- * lock on an extent buffer that btrfs_create_pending_block_groups() may
- * try to COW later.
- */
- if (root == fs_info->extent_root ||
- root == fs_info->chunk_root ||
- root == fs_info->dev_root ||
- root == fs_info->free_space_root)
- trans->can_flush_pending_bgs = false;
-
- cow = btrfs_alloc_tree_block(trans, root, parent_start,
- root->root_key.objectid, &disk_key, level,
- search_start, empty_size);
- trans->can_flush_pending_bgs = true;
+ cow = alloc_tree_block_no_bg_flush(trans, root, parent_start, &disk_key,
+ level, search_start, empty_size);
if (IS_ERR(cow))
return PTR_ERR(cow);
@@ -3345,8 +3367,8 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
else
btrfs_node_key(lower, &lower_key, 0);
- c = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &lower_key, level, root->node->start, 0);
+ c = alloc_tree_block_no_bg_flush(trans, root, 0, &lower_key, level,
+ root->node->start, 0);
if (IS_ERR(c))
return PTR_ERR(c);
@@ -3475,8 +3497,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
mid = (c_nritems + 1) / 2;
btrfs_node_key(c, &disk_key, mid);
- split = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, level, c->start, 0);
+ split = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, level,
+ c->start, 0);
if (IS_ERR(split))
return PTR_ERR(split);
@@ -4260,8 +4282,8 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
else
btrfs_item_key(l, &disk_key, mid);
- right = btrfs_alloc_tree_block(trans, root, 0, root->root_key.objectid,
- &disk_key, 0, l->start, 0);
+ right = alloc_tree_block_no_bg_flush(trans, root, 0, &disk_key, 0,
+ l->start, 0);
if (IS_ERR(right))
return PTR_ERR(right);
This is a note to let you know that I've just added the patch titled
tools: iio: iio_generic_buffer: make num_loops signed
to my staging git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git
in the staging-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From b119d3bc328e7a9574861ebe0c2110e2776c2de1 Mon Sep 17 00:00:00 2001
From: Martin Kelly <mkelly(a)xevo.com>
Date: Fri, 11 Jan 2019 23:13:09 +0000
Subject: tools: iio: iio_generic_buffer: make num_loops signed
Currently, num_loops is unsigned, but it's set by strtoll, which returns a
(signed) long long int. This could lead to overflow, and it also makes the
check "num_loops < 0" always be false, since num_loops is unsigned.
Setting num_loops to -1 to loop forever is almost working because num_loops
is getting set to a very high number, but it's technically still incorrect.
Fix this issue by making num_loops signed. This also fixes an error found
by Smatch.
Signed-off-by: Martin Kelly <mkelly(a)xevo.com>
Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com>
Fixes: 55dda0abcf9d ("tools: iio: iio_generic_buffer: allow continuous looping")
Cc: <Stable(a)vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com>
---
tools/iio/iio_generic_buffer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
index 3040830d7797..84545666a09c 100644
--- a/tools/iio/iio_generic_buffer.c
+++ b/tools/iio/iio_generic_buffer.c
@@ -330,7 +330,7 @@ static const struct option longopts[] = {
int main(int argc, char **argv)
{
- unsigned long long num_loops = 2;
+ long long num_loops = 2;
unsigned long timedelay = 1000000;
unsigned long buf_len = 128;
--
2.20.1