linux-stable.git/drivers/block/drbd, branch v4.14.166

drbd: Change drbd_request_detach_interruptible's return type to int

2019-12-17T19:39:55+00:00

[ Upstream commit 5816a0932b4fd74257b8cc5785bc8067186a8723 ]

Clang warns when an implicit conversion is done between enumerated
types:

drivers/block/drbd/drbd_state.c:708:8: warning: implicit conversion from
enumeration type 'enum drbd_ret_code' to different enumeration type
'enum drbd_state_rv' [-Wenum-conversion]
                rv = ERR_INTR;
                   ~ ^~~~~~~~

drbd_request_detach_interruptible's only call site is in the return
statement of adm_detach, which returns an int. Change the return type of
drbd_request_detach_interruptible to match, silencing Clang's warning.

Reported-by: Nick Desaulniers 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Nathan Chancellor 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: fix print_st_err()'s prototype to match the definition

2019-12-05T14:37:45+00:00

[ Upstream commit 2c38f035117331eb78d0504843c79ea7c7fabf37 ]

print_st_err() is defined with its 4th argument taking an
'enum drbd_state_rv' but its prototype use an int for it.

Fix this by using 'enum drbd_state_rv' in the prototype too.

Signed-off-by: Luc Van Oostenryck 
Signed-off-by: Roland Kammerer 
Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: do not block when adjusting "disk-options" while IO is frozen

2019-12-05T14:37:45+00:00

[ Upstream commit f708bd08ecbdc23d03aaedf5b3311ebe44cfdb50 ]

"suspending" IO is overloaded.
It can mean "do not allow new requests" (obviously),
but it also may mean "must not complete pending IO",
for example while the fencing handlers do their arbitration.

When adjusting disk options, we suspend io (disallow new requests), then
wait for the activity-log to become unused (drain all IO completions),
and possibly replace it with a new activity log of different size.

If the other "suspend IO" aspect is active, pending IO completions won't
happen, and we would block forever (unkillable drbdsetup process).

Fix this by skipping the activity log adjustment if the "al-extents"
setting did not change. Also, in case it did change, fail early without
blocking if it looks like we would block forever.

Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: reject attach of unsuitable uuids even if connected

2019-12-05T14:37:44+00:00

[ Upstream commit fe43ed97bba3b11521abd934b83ed93143470e4f ]

Multiple failure scenario:
a) all good
   Connected Primary/Secondary UpToDate/UpToDate
b) lose disk on Primary,
   Connected Primary/Secondary Diskless/UpToDate
c) continue to write to the device,
   changes only make it to the Secondary storage.
d) lose disk on Secondary,
   Connected Primary/Secondary Diskless/Diskless
e) now try to re-attach on Primary

This would have succeeded before, even though that is clearly the
wrong data set to attach to (missing the modifications from c).
Because we only compared our "effective" and the "to-be-attached"
data generation uuid tags if (device->state.conn < C_CONNECTED).

Fix: change that constraint to (device->state.pdsk != D_UP_TO_DATE)
compare the uuids, and reject the attach.

This patch also tries to improve the reverse scenario:
first lose Secondary, then Primary disk,
then try to attach the disk on Secondary.

Before this patch, the attach on the Secondary succeeds, but since commit
drbd: disconnect, if the wrong UUIDs are attached on a connected peer
the Primary will notice unsuitable data, and drop the connection hard.

Though unfortunately at a point in time during the handshake where
we cannot easily abort the attach on the peer without more
refactoring of the handshake.

We now reject any attach to "unsuitable" uuids,
as long as we can see a Primary role,
unless we already have access to "good" data.

Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: ignore "all zero" peer volume sizes in handshake

2019-12-05T14:37:44+00:00

[ Upstream commit 94c43a13b8d6e3e0dd77b3536b5e04a84936b762 ]

During handshake, if we are diskless ourselves, we used to accept any size
presented by the peer.

Which could be zero if that peer was just brought up and connected
to us without having a disk attached first, in which case both
peers would just "flip" their volume sizes.

Now, even a diskless node will ignore "zero" sizes
presented by a diskless peer.

Also a currently Diskless Primary will refuse to shrink during handshake:
it may be frozen, and waiting for a "suitable" local disk or peer to
re-appear (on-no-data-accessible suspend-io). If the peer is smaller
than what we used to be, it is not suitable.

The logic for a diskless node during handshake is now supposed to be:
believe the peer, if
 - I don't have a current size myself
 - we agree on the size anyways
 - I do have a current size, am Secondary, and he has the only disk
 - I do have a current size, am Primary, and he has the only disk,
   which is larger than my current size

Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

block: drbd: remove a stray unlock in __drbd_send_protocol()

2019-12-05T14:37:07+00:00

[ Upstream commit 8e9c523016cf9983b295e4bc659183d1fa6ef8e0 ]

There are two callers of this function and they both unlock the mutex so
this ends up being a double unlock.

Fixes: 44ed167da748 ("drbd: rcu_read_lock() and rcu_dereference() for tconn->net_conf")
Signed-off-by: Dan Carpenter 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: dynamically allocate shash descriptor

2019-08-16T08:13:53+00:00

[ Upstream commit 77ce56e2bfaa64127ae5e23ef136c0168b818777 ]

Building with clang and KASAN, we get a warning about an overly large
stack frame on 32-bit architectures:

drivers/block/drbd/drbd_receiver.c:921:31: error: stack frame size of 1280 bytes in function 'conn_connect'
      [-Werror,-Wframe-larger-than=]

We already allocate other data dynamically in this function, so
just do the same for the shash descriptor, which makes up most of
this memory.

Link: https://lore.kernel.org/lkml/20190617132440.2721536-1-arnd@arndb.de/
Reviewed-by: Kees Cook 
Reviewed-by: Roland Kammerer 
Signed-off-by: Arnd Bergmann 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: skip spurious timeout (ping-timeo) when failing promote

2019-02-12T18:46:06+00:00

[ Upstream commit 9848b6ddd8c92305252f94592c5e278574e7a6ac ]

If you try to promote a Secondary while connected to a Primary
and allow-two-primaries is NOT set, we will wait for "ping-timeout"
to give this node a chance to detect a dead primary,
in case the cluster manager noticed faster than we did.

But if we then are *still* connected to a Primary,
we fail (after an additional timeout of ping-timout).

This change skips the spurious second timeout.

Most people won't notice really,
since "ping-timeout" by default is half a second.

But in some installations, ping-timeout may be 10 or 20 seconds or more,
and spuriously delaying the error return becomes annoying.

Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: disconnect, if the wrong UUIDs are attached on a connected peer

2019-02-12T18:46:06+00:00

[ Upstream commit b17b59602b6dcf8f97a7dc7bc489a48388d7063a ]

With "on-no-data-accessible suspend-io", DRBD requires the next attach
or connect to be to the very same data generation uuid tag it lost last.

If we first lost connection to the peer,
then later lost connection to our own disk,
we would usually refuse to re-connect to the peer,
because it presents the wrong data set.

However, if the peer first connects without a disk,
and then attached its disk, we accepted that same wrong data set,
which would be "unexpected" by any user of that DRBD
and cause "undefined results" (read: very likely data corruption).

The fix is to forcefully disconnect as soon as we notice that the peer
attached to the "wrong" dataset.

Signed-off-by: Lars Ellenberg 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin

drbd: narrow rcu_read_lock in drbd_sync_handshake

2019-02-12T18:46:06+00:00

[ Upstream commit d29e89e34952a9ad02c77109c71a80043544296e ]

So far there was the possibility that we called
genlmsg_new(GFP_NOIO)/mutex_lock() while holding an rcu_read_lock().

This included cases like:

drbd_sync_handshake (acquire the RCU lock)
  drbd_asb_recover_1p
    drbd_khelper
      drbd_bcast_event
        genlmsg_new(GFP_NOIO) --> may sleep

drbd_sync_handshake (acquire the RCU lock)
  drbd_asb_recover_1p
    drbd_khelper
      notify_helper
        genlmsg_new(GFP_NOIO) --> may sleep

drbd_sync_handshake (acquire the RCU lock)
  drbd_asb_recover_1p
    drbd_khelper
      notify_helper
        mutex_lock --> may sleep

While using GFP_ATOMIC whould have been possible in the first two cases,
the real fix is to narrow the rcu_read_lock.

Reported-by: Jia-Ju Bai 
Reviewed-by: Lars Ellenberg 
Signed-off-by: Roland Kammerer 
Signed-off-by: Jens Axboe 
Signed-off-by: Sasha Levin