kernel/linux.git/drivers/block/drbd, branch v4.14.263

signal: Allow cifs and drbd to receive their terminating signals

2020-01-27T13:46:43+00:00

[ Upstream commit 33da8e7c814f77310250bb54a9db36a44c5de784 ] My recent to change to only use force_sig for a synchronous events wound up breaking signal reception cifs and drbd. I had overlooked the fact that by default kthreads start out with all signals set to SIG_IGN. So a change I thought was safe turned out to have made it impossible for those kernel thread to catch their signals. Reverting the work on force_sig is a bad idea because what the code was doing was very much a misuse of force_sig. As the way force_sig ultimately allowed the signal to happen was to change the signal handler to SIG_DFL. Which after the first signal will allow userspace to send signals to these kernel threads. At least for wake_ack_receiver in drbd that does not appear actively wrong. So correct this problem by adding allow_kernel_signal that will allow signals whose siginfo reports they were sent by the kernel through, but will not allow userspace generated signals, and update cifs and drbd to call allow_kernel_signal in an appropriate place so that their thread can receive this signal. Fixing things this way ensures that userspace won't be able to send signals and cause problems, that it is clear which signals the threads are expecting to receive, and it guarantees that nothing else in the system will be affected. This change was partly inspired by similar cifs and drbd patches that added allow_signal. Reported-by: ronnie sahlberg Reported-by: Christoph Böhmwalder Tested-by: Christoph Böhmwalder Cc: Steve French Cc: Philipp Reisner Cc: David Laight Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes") Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig") Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig") Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig") Signed-off-by: "Eric W. Biederman" Signed-off-by: Sasha Levin

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