From: Xiubo Li <xiubli@xxxxxxxxxx>
[ Upstream commit 825978fd6a0defc3c29d8a38b6cea76a0938d21e ]
1, mount with wsync.
2, create a file with O_RDWR, and the request was sent to mds.0:
ceph_atomic_open()-->
ceph_mdsc_do_request(openc)
finish_open(file, dentry, ceph_open)-->
ceph_open()-->
ceph_init_file()-->
ceph_init_file_info()-->
ceph_uninline_data()-->
{
...
if (inline_version == 1 || /* initial version, no data */
inline_version == CEPH_INLINE_NONE)
goto out_unlock;
...
}
The inline_version will be 1, which is the initial version for the
new create file. And here the ci->i_inline_version will keep with 1,
it's buggy.
3, buffer write to the file immediately:
ceph_write_iter()-->
ceph_get_caps(file, need=Fw, want=Fb, ...);
generic_perform_write()-->
a_ops->write_begin()-->
ceph_write_begin()-->
netfs_write_begin()-->
netfs_begin_read()-->
netfs_rreq_submit_slice()-->
netfs_read_from_server()-->
rreq->netfs_ops->issue_read()-->
ceph_netfs_issue_read()-->
{
...
if (ci->i_inline_version != CEPH_INLINE_NONE &&
ceph_netfs_issue_op_inline(subreq))
return;
...
}
ceph_put_cap_refs(ci, Fwb);
The ceph_netfs_issue_op_inline() will send a getattr(Fsr) request to
mds.1.
4, then the mds.1 will request the rd lock for CInode::filelock from
the auth mds.0, the mds.0 will do the CInode::filelock state transation
from excl --> sync, but it need to revoke the Fxwb caps back from the
clients.
While the kernel client has aleady held the Fwb caps and waiting for
the getattr(Fsr).
It's deadlock!
URL: https://tracker.ceph.com/issues/55377
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ceph/addr.c | 33 +++++++++++++++++++--------------
1 file changed, 19 insertions(+), 14 deletions(-)
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index b6edcf89a429..adef10a6e5c7 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1644,7 +1644,7 @@ int ceph_uninline_data(struct file *file)
struct inode *inode = file_inode(file);
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
- struct ceph_osd_request *req;
+ struct ceph_osd_request *req = NULL;
struct ceph_cap_flush *prealloc_cf;
struct folio *folio = NULL;
u64 inline_version = CEPH_INLINE_NONE;
@@ -1652,10 +1652,23 @@ int ceph_uninline_data(struct file *file)
int err = 0;
u64 len;
+ spin_lock(&ci->i_ceph_lock);
+ inline_version = ci->i_inline_version;
+ spin_unlock(&ci->i_ceph_lock);
+
+ dout("uninline_data %p %llx.%llx inline_version %llu\n",
+ inode, ceph_vinop(inode), inline_version);
+
+ if (inline_version == CEPH_INLINE_NONE)
+ return 0;
+
prealloc_cf = ceph_alloc_cap_flush();
if (!prealloc_cf)
return -ENOMEM;
+ if (inline_version == 1) /* initial version, no data */
+ goto out_uninline;
+
folio = read_mapping_folio(inode->i_mapping, 0, file);
if (IS_ERR(folio)) {
err = PTR_ERR(folio);
@@ -1664,17 +1677,6 @@ int ceph_uninline_data(struct file *file)
folio_lock(folio);
- spin_lock(&ci->i_ceph_lock);
- inline_version = ci->i_inline_version;
- spin_unlock(&ci->i_ceph_lock);
-
- dout("uninline_data %p %llx.%llx inline_version %llu\n",
- inode, ceph_vinop(inode), inline_version);
-
- if (inline_version == 1 || /* initial version, no data */
- inline_version == CEPH_INLINE_NONE)
- goto out_unlock;
-
len = i_size_read(inode);
if (len > folio_size(folio))
len = folio_size(folio);
@@ -1739,6 +1741,7 @@ int ceph_uninline_data(struct file *file)
ceph_update_write_metrics(&fsc->mdsc->metric, req->r_start_latency,
req->r_end_latency, len, err);
+out_uninline:
if (!err) {
int dirty;
@@ -1757,8 +1760,10 @@ int ceph_uninline_data(struct file *file)
if (err == -ECANCELED)
err = 0;
out_unlock:
- folio_unlock(folio);
- folio_put(folio);
+ if (folio) {
+ folio_unlock(folio);
+ folio_put(folio);
+ }
out:
ceph_free_cap_flush(prealloc_cf);
dout("uninline_data %p %llx.%llx inline_version %llu = %d\n",
--
2.35.1
