| Message ID | 20190614030229.22375-1-lsahlber@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | cifs: fix GlobalMid_Lock bug in cifs_reconnect | expand |
tentatively merged into cifs-2.6.git for-next and to the github tree On Thu, Jun 13, 2019 at 10:02 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote: > > We can not hold the GlobalMid_Lock spinlock during the > dfs processing in cifs_reconnect since it invokes things that may sleep > and thus trigger : > > BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23 > > Thus we need to drop the spinlock during this code block. > > RHBZ: 1716743 > > Cc: stable@vger.kernel.org > Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> > --- > fs/cifs/connect.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > index 8c4121da624e..8dd6637a3cbb 100644 > --- a/fs/cifs/connect.c > +++ b/fs/cifs/connect.c > @@ -476,6 +476,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > spin_lock(&GlobalMid_Lock); > server->nr_targets = 1; > #ifdef CONFIG_CIFS_DFS_UPCALL > + spin_unlock(&GlobalMid_Lock); > cifs_sb = find_super_by_tcp(server); > if (IS_ERR(cifs_sb)) { > rc = PTR_ERR(cifs_sb); > @@ -493,6 +494,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > } > cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__, > server->nr_targets); > + spin_lock(&GlobalMid_Lock); > #endif > if (server->tcpStatus == CifsExiting) { > /* the demux thread will exit normally > -- > 2.13.6 >
Acked-by: Pavel Shilovsky <pshilov@microsoft.com> -- Best regards, Pavel Shilovsky чт, 13 июн. 2019 г. в 20:57, Steve French <smfrench@gmail.com>: > > tentatively merged into cifs-2.6.git for-next and to the github tree > > On Thu, Jun 13, 2019 at 10:02 PM Ronnie Sahlberg <lsahlber@redhat.com> wrote: > > > > We can not hold the GlobalMid_Lock spinlock during the > > dfs processing in cifs_reconnect since it invokes things that may sleep > > and thus trigger : > > > > BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23 > > > > Thus we need to drop the spinlock during this code block. > > > > RHBZ: 1716743 > > > > Cc: stable@vger.kernel.org > > Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> > > --- > > fs/cifs/connect.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c > > index 8c4121da624e..8dd6637a3cbb 100644 > > --- a/fs/cifs/connect.c > > +++ b/fs/cifs/connect.c > > @@ -476,6 +476,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > spin_lock(&GlobalMid_Lock); > > server->nr_targets = 1; > > #ifdef CONFIG_CIFS_DFS_UPCALL > > + spin_unlock(&GlobalMid_Lock); > > cifs_sb = find_super_by_tcp(server); > > if (IS_ERR(cifs_sb)) { > > rc = PTR_ERR(cifs_sb); > > @@ -493,6 +494,7 @@ cifs_reconnect(struct TCP_Server_Info *server) > > } > > cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__, > > server->nr_targets); > > + spin_lock(&GlobalMid_Lock); > > #endif > > if (server->tcpStatus == CifsExiting) { > > /* the demux thread will exit normally > > -- > > 2.13.6 > > > > > -- > Thanks, > > Steve
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 8c4121da624e..8dd6637a3cbb 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -476,6 +476,7 @@ cifs_reconnect(struct TCP_Server_Info *server) spin_lock(&GlobalMid_Lock); server->nr_targets = 1; #ifdef CONFIG_CIFS_DFS_UPCALL + spin_unlock(&GlobalMid_Lock); cifs_sb = find_super_by_tcp(server); if (IS_ERR(cifs_sb)) { rc = PTR_ERR(cifs_sb); @@ -493,6 +494,7 @@ cifs_reconnect(struct TCP_Server_Info *server) } cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__, server->nr_targets); + spin_lock(&GlobalMid_Lock); #endif if (server->tcpStatus == CifsExiting) { /* the demux thread will exit normally
We can not hold the GlobalMid_Lock spinlock during the dfs processing in cifs_reconnect since it invokes things that may sleep and thus trigger : BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23 Thus we need to drop the spinlock during this code block. RHBZ: 1716743 Cc: stable@vger.kernel.org Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> --- fs/cifs/connect.c | 2 ++ 1 file changed, 2 insertions(+)