Commit Graph

253 Commits

Author SHA1 Message Date
Martin K. Petersen
11e50ed239 Merge branch '5.19/scsi-fixes' into 5.20/scsi-staging
Bring in fixes to resolve a merge conflict in the lpfc driver update.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-07-07 17:20:43 -04:00
Mike Christie
bb42856bfd scsi: iscsi: Add helper to remove a session from the kernel
During qedi shutdown we need to stop the iSCSI layer from sending new nops
as pings and from responding to target ones and make sure there is no
running connection cleanups. Commit d1f2ce7763 ("scsi: qedi: Fix host
removal with running sessions") converted the driver to use the libicsi
helper to drive session removal, so the above issues could be handled. The
problem is that during system shutdown iscsid will not be running so when
we try to remove the root session we will hang waiting for userspace to
reply.

Add a helper that will drive the destruction of sessions like these during
system shutdown.

Link: https://lore.kernel.org/r/20220616222738.5722-5-michael.christie@oracle.com
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:54 -04:00
Mike Christie
da2f132d00 scsi: iscsi: Clean up bound endpoints during shutdown
In the next patch we allow drivers to drive session removal during
shutdown. In this case iscsid will not be running, so we need to detect
bound endpoints and disconnect them. This moves the bound ep check so we
now always check.

Link: https://lore.kernel.org/r/20220616222738.5722-4-michael.christie@oracle.com
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:53 -04:00
Mike Christie
3328333b47 scsi: iscsi: Allow iscsi_if_stop_conn() to be called from kernel
iscsi_if_stop_conn() is only called from the userspace interface but in a
subsequent commit we will want to call it from the kernel interface to
allow drivers like qedi to remove sessions from inside the kernel during
shutdown. This removes the iscsi_uevent code from iscsi_if_stop_conn() so we
can call it in a new helper.

Link: https://lore.kernel.org/r/20220616222738.5722-3-michael.christie@oracle.com
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:53 -04:00
Mike Christie
c577ab7ba5 scsi: iscsi: Fix HW conn removal use after free
If qla4xxx doesn't remove the connection before the session, the iSCSI
class tries to remove the connection for it. We were doing a
iscsi_put_conn() in the iter function which is not needed and will result
in a use after free because iscsi_remove_conn() will free the connection.

Link: https://lore.kernel.org/r/20220616222738.5722-2-michael.christie@oracle.com
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:53 -04:00
Max Gurtovoy
6a33ed5064 scsi: iscsi: Make iscsi_unregister_transport() return void
This function always returns 0. We can make it return void to simplify the
code. Also, no caller ever checks the return value of this function.

Link: https://lore.kernel.org/r/20220616080210.18531-1-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-16 22:11:18 -04:00
Sergey Gorenko
f6eed15f3e scsi: iscsi: Exclude zero from the endpoint ID range
The kernel returns an endpoint ID as r.ep_connect_ret.handle in the
iscsi_uevent. The iscsid validates a received endpoint ID and treats zero
as an error. The commit referenced in the fixes line changed the endpoint
ID range, and zero is always assigned to the first endpoint ID.  So, the
first attempt to create a new iSER connection always fails.

Link: https://lore.kernel.org/r/20220613123854.55073-1-sergeygo@nvidia.com
Fixes: 3c6ae371b8 ("scsi: iscsi: Release endpoint ID when its freed")
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Sergey Gorenko <sergeygo@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-13 22:11:36 -04:00
keliu
3fd3a52ca6 scsi: core: iscsi: Directly use ida_alloc()/ida_free()
Use ida_alloc()/ida_free() instead of the deprecated
ida_simple_get()/ida_simple_remove() interface.

Link: https://lore.kernel.org/r/20220527083049.2552526-1-liuke94@huawei.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: keliu <liuke94@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-07 21:58:06 -04:00
Mike Christie
03690d8197 scsi: iscsi: Fix unbound endpoint error handling
If a driver raises a connection error before the connection is bound, we
can leave a cleanup_work queued that can later run and disconnect/stop a
connection that is logged in. The problem is that drivers can call
iscsi_conn_error_event for endpoints that are connected but not yet bound
when something like the network port they are using is brought down.
iscsi_cleanup_conn_work_fn will check for this and exit early, but if the
cleanup_work is stuck behind other works, it might not get run until after
userspace has done ep_disconnect. Because the endpoint is not yet bound
there was no way for ep_disconnect to flush the work.

The bug of leaving stop_conns queued was added in:

Commit 23d6fefbb3 ("scsi: iscsi: Fix in-kernel conn failure handling")

and:

Commit 0ab710458d ("scsi: iscsi: Perform connection failure entirely in
kernel space")

was supposed to fix it, but left this case.

This patch moves the conn state check to before we even queue the work so
we can avoid queueing.

Link: https://lore.kernel.org/r/20220408001314.5014-7-michael.christie@oracle.com
Fixes: 0ab710458d ("scsi: iscsi: Perform connection failure entirely in kernel space")
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:35 -04:00
Mike Christie
7c6e99c181 scsi: iscsi: Fix conn cleanup and stop race during iscsid restart
If iscsid is doing a stop_conn at the same time the kernel is starting
error recovery we can hit a race that allows the cleanup work to run on a
valid connection. In the race, iscsi_if_stop_conn sees the cleanup bit set,
but it calls flush_work on the clean_work before iscsi_conn_error_event has
queued it. The flush then returns before the queueing and so the
cleanup_work can run later and disconnect/stop a conn while it's in a
connected state.

The patch:

Commit 0ab710458d ("scsi: iscsi: Perform connection failure entirely in
kernel space")

added the late stop_conn call bug originally, and the patch:

Commit 23d6fefbb3 ("scsi: iscsi: Fix in-kernel conn failure handling")

attempted to fix it but only fixed the normal EH case and left the above
race for the iscsid restart case. For the normal EH case we don't hit the
race because we only signal userspace to start recovery after we have done
the queueing, so the flush will always catch the queued work or see it
completed.

For iscsid restart cases like boot, we can hit the race because iscsid will
call down to the kernel before the kernel has signaled any error, so both
code paths can be running at the same time. This adds a lock around the
setting of the cleanup bit and queueing so they happen together.

Link: https://lore.kernel.org/r/20220408001314.5014-6-michael.christie@oracle.com
Fixes: 0ab710458d ("scsi: iscsi: Perform connection failure entirely in kernel space")
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:34 -04:00
Mike Christie
0aadafb5c3 scsi: iscsi: Fix endpoint reuse regression
This patch fixes a bug where when using iSCSI offload we can free an
endpoint while userspace still thinks it's active. That then causes the
endpoint ID to be reused for a new connection's endpoint while userspace
still thinks the ID is for the original connection. Userspace will then end
up disconnecting a running connection's endpoint or trying to bind to
another connection's endpoint.

This bug is a regression added in:

Commit 23d6fefbb3 ("scsi: iscsi: Fix in-kernel conn failure handling")

where we added a in kernel ep_disconnect call to fix a bug in:

Commit 0ab710458d ("scsi: iscsi: Perform connection failure entirely in
kernel space")

where we would call stop_conn without having done ep_disconnect. This early
ep_disconnect call will then free the endpoint and it's ID while userspace
still thinks the ID is valid.

Fix the early release of the ID by having the in kernel recovery code keep
a reference to the endpoint until userspace has called into the kernel to
finish cleaning up the endpoint/connection. It requires the previous commit
"scsi: iscsi: Release endpoint ID when its freed" which moved the freeing
of the ID until when the endpoint is released.

Link: https://lore.kernel.org/r/20220408001314.5014-5-michael.christie@oracle.com
Fixes: 23d6fefbb3 ("scsi: iscsi: Fix in-kernel conn failure handling")
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:34 -04:00
Mike Christie
3c6ae371b8 scsi: iscsi: Release endpoint ID when its freed
We can't release the endpoint ID until all references to the endpoint have
been dropped or it could be allocated while in use. This has us use an idr
instead of looping over all conns to find a free ID and then free the ID
when all references have been dropped instead of when the device is only
deleted.

Link: https://lore.kernel.org/r/20220408001314.5014-4-michael.christie@oracle.com
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Reviewed-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:34 -04:00
Mike Christie
cbd2283aaf scsi: iscsi: Fix offload conn cleanup when iscsid restarts
When userspace restarts during boot or upgrades it won't know about the
offload driver's endpoint and connection mappings. iscsid will start by
cleaning up the old session by doing a stop_conn call. Later, if we are
able to create a new connection, we clean up the old endpoint during the
binding stage. The problem is that if we do stop_conn before doing the
ep_disconnect call offload, drivers can still be executing I/O. We then
might free tasks from the under the card/driver.

This moves the ep_disconnect call to before we do the stop_conn call for
this case. It will then work and look like a normal recovery/cleanup
procedure from the driver's point of view.

Link: https://lore.kernel.org/r/20220408001314.5014-3-michael.christie@oracle.com
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:34 -04:00
Mike Christie
c34f95e98d scsi: iscsi: Move iscsi_ep_disconnect()
This patch moves iscsi_ep_disconnect() so it can be called earlier in the
next patch.

Link: https://lore.kernel.org/r/20220408001314.5014-2-michael.christie@oracle.com
Tested-by: Manish Rangankar <mrangankar@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-04-11 22:09:34 -04:00
Wenchao Hao
8709c32309 scsi: libiscsi: Teardown iscsi_cls_conn gracefully
Commit 1b8d0300a3 ("scsi: libiscsi: Fix UAF in
iscsi_conn_get_param()/iscsi_conn_teardown()") fixed an UAF in
iscsi_conn_get_param() and introduced 2 tmp_xxx varibles.

We can gracefully fix this UAF with the help of device_del(). Calling
iscsi_remove_conn() at the beginning of iscsi_conn_teardown would make
userspace unable to see iscsi_cls_conn. This way we we can free memory
safely.

Remove iscsi_destroy_conn() since it is no longer used.

Link: https://lore.kernel.org/r/20220310015759.3296841-4-haowenchao@huawei.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-15 00:20:16 -04:00
Wenchao Hao
7dae459f5e scsi: libiscsi: Add iscsi_cls_conn to sysfs after initialization
iscsi_create_conn() exposed iscsi_cls_conn to sysfs prior to initialization
of iscsi_conn's dd_data. When userspace tried to access an attribute such
as the connect address, a NULL pointer dereference was observed.

Do not add iscsi_cls_conn to sysfs until it has been initialized.  Remove
iscsi_create_conn() since it is no longer used.

Link: https://lore.kernel.org/r/20220310015759.3296841-3-haowenchao@huawei.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-15 00:19:50 -04:00
Wenchao Hao
ad515cada7 scsi: iscsi: Add helper functions to manage iscsi_cls_conn
- iscsi_alloc_conn(): Allocate and initialize iscsi_cls_conn

 - iscsi_add_conn(): Expose iscsi_cls_conn to userspace via sysfs

 - iscsi_remove_conn(): Remove iscsi_cls_conn from sysfs

Link: https://lore.kernel.org/r/20220310015759.3296841-2-haowenchao@huawei.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Wenchao Hao <haowenchao@huawei.com>
Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-15 00:19:50 -04:00
Mike Christie
7cb6683ce7 scsi: iscsi: Use the session workqueue for recovery
Use the session workqueue for recovery and unbinding. If there are delays
during device blocking/cleanup then it will no longer affect other
sessions.

Link: https://lore.kernel.org/r/20220226230435.38733-6-michael.christie@oracle.com
Reviewed-by: Chris Leech <cleech@redhat.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 23:56:28 -05:00
Mike Christie
5842ea3668 scsi: iscsi: ql4xxx: Use per-session workqueue for unbinding
We currently allocate a workqueue per host and only use it for removing the
target. For the session per host case we could be using this workqueue to
be able to do recoveries (block, unblock, timeout handling) in parallel. To
also allow offload drivers to do their session recoveries in parallel, this
drops the per host workqueue and replaces it with a per session one.

Link: https://lore.kernel.org/r/20220226230435.38733-5-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 23:56:28 -05:00
Mike Christie
d8ec5d67b8 scsi: iscsi: Remove iscsi_scan_finished()
qla4xxx does not use iscsi_scan_finished() anymore so remove it.

Link: https://lore.kernel.org/r/20220226230435.38733-4-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 23:56:28 -05:00
Mike Christie
b07c348f8f scsi: iscsi: Speed up session unblocking and removal
When the iSCSI class was added upstream, blocking a queue was fast because
it just set some flag bits and didn't handle I/O that was in the process of
being sent to the driver. That's no longer the case so blocking a queue is
expensive and we can end up with a backlog of blocks by the time we have
relogged in and are trying to start the queues.

For the session unblock case, this has try to cancel the block and recovery
work in case they are still queued so we can avoid unneeded queue
manipulations. For removal, we also now try to cancel all the recovery
related works since a couple lines down we will set the session and device
state so running those functions are not necessary.

Link: https://lore.kernel.org/r/20220226230435.38733-3-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 23:56:28 -05:00
Mike Christie
8dd3dff3bf scsi: iscsi: Fix recovery and unblocking race
If the user sets the iscsi_eh_timer_workq/iscsi_eh workqueue's max_active
to greater than 1, the recovery_work could be running when
__iscsi_unblock_session() runs. The cancel_delayed_work() will then not
wait for the running work and we can race where we end up with the wrong
session state and scsi_device state set.

This replaces the cancel_delayed_work() with the sync version.

Link: https://lore.kernel.org/r/20220226230435.38733-2-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-03-01 23:56:28 -05:00
Mike Christie
a0c2f8b670 scsi: iscsi: Unblock session then wake up error handler
We can race where iscsi_session_recovery_timedout() has woken up the error
handler thread and it's now setting the devices to offline, and
session_recovery_timedout()'s call to scsi_target_unblock() is also trying
to set the device's state to transport-offline. We can then get a mix of
states.

For the case where we can't relogin we want the devices to be in
transport-offline so when we have repaired the connection
__iscsi_unblock_session() can set the state back to running.

Set the device state then call into libiscsi to wake up the error handler.

Link: https://lore.kernel.org/r/20211105221048.6541-2-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-11-16 19:42:30 -05:00
Mike Christie
187a580c9e scsi: iscsi: Fix set_param() handling
In commit 9e67600ed6 ("scsi: iscsi: Fix race condition between login and
sync thread") we meant to add a check where before we call ->set_param() we
make sure the iscsi_cls_connection is bound. The problem is that between
versions 4 and 5 of the patch the deletion of the unchecked set_param()
call was dropped so we ended up with 2 calls. As a result we can still hit
a crash where we access the unbound connection on the first call.

This patch removes that first call.

Fixes: 9e67600ed6 ("scsi: iscsi: Fix race condition between login and sync thread")
Link: https://lore.kernel.org/r/20211010161904.60471-1-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Li Feng <fengli@smartx.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-10-12 12:51:25 -04:00
Baokun Li
4e28550829 scsi: iscsi: Adjust iface sysfs attr detection
ISCSI_NET_PARAM_IFACE_ENABLE belongs to enum iscsi_net_param instead of
iscsi_iface_param so move it to ISCSI_NET_PARAM. Otherwise, when we call
into the driver, we might not match and return that we don't want attr
visible in sysfs. Found in code review.

Link: https://lore.kernel.org/r/20210901085336.2264295-1-libaokun1@huawei.com
Fixes: e746f3451e ("scsi: iscsi: Fix iface sysfs attr detection")
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-09-13 22:15:43 -04:00
Mike Christie
e746f3451e scsi: iscsi: Fix iface sysfs attr detection
A ISCSI_IFACE_PARAM can have the same value as a ISCSI_NET_PARAM so when
iscsi_iface_attr_is_visible tries to figure out the type by just checking
the value, we can collide and return the wrong type. When we call into the
driver we might not match and return that we don't want attr visible in
sysfs. The patch fixes this by setting the type when we figure out what the
param is.

Link: https://lore.kernel.org/r/20210701002559.89533-1-michael.christie@oracle.com
Fixes: 3e0f65b34c ("[SCSI] iscsi_transport: Additional parameters for network settings")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-07-18 21:07:48 -04:00
Mike Christie
7ce9fc5ecd scsi: iscsi: Flush block work before unblock
We set the max_active iSCSI EH works to 1, so all work is going to execute
in order by default. However, userspace can now override this in sysfs. If
max_active > 1, we can end up with the block_work on CPU1 and
iscsi_unblock_session running the unblock_work on CPU2 and the session and
target/device state will end up out of sync with each other.

This adds a flush of the block_work in iscsi_unblock_session.

Link: https://lore.kernel.org/r/20210525181821.7617-17-michael.christie@oracle.com
Fixes: 1d726aa6ef ("scsi: iscsi: Optimize work queue flush use")
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:21 -04:00
Mike Christie
b1d19e8c92 scsi: iscsi: Add iscsi_cls_conn refcount helpers
There are a couple places where we could free the iscsi_cls_conn while it's
still in use. This adds some helpers to get/put a refcount on the struct
and converts an exiting user. Subsequent commits will then use the helpers
to fix 2 bugs in the eh code.

Link: https://lore.kernel.org/r/20210525181821.7617-11-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:20 -04:00
Mike Christie
23d6fefbb3 scsi: iscsi: Fix in-kernel conn failure handling
Commit 0ab710458d ("scsi: iscsi: Perform connection failure entirely in
kernel space") has the following regressions/bugs that this patch fixes:

1. It can return cmds to upper layers like dm-multipath where that can
retry them. After they are successful the fs/app can send new I/O to the
same sectors, but we've left the cmds running in FW or in the net layer.
We need to be calling ep_disconnect if userspace is not up.

This patch only fixes the issue for offload drivers. iscsi_tcp will be
fixed in separate commit because it doesn't have a ep_disconnect call.

2. The drivers that implement ep_disconnect expect that it's called before
conn_stop. Besides crashes, if the cleanup_task callout is called before
ep_disconnect it might free up driver/card resources for session1 then they
could be allocated for session2. But because the driver's ep_disconnect is
not called it has not cleaned up the firmware so the card is still using
the resources for the original cmd.

3. The stop_conn_work_fn can run after userspace has done its recovery and
we are happily using the session. We will then end up with various bugs
depending on what is going on at the time.

We may also run stop_conn_work_fn late after userspace has called stop_conn
and ep_disconnect and is now going to call start/bind conn. If
stop_conn_work_fn runs after bind but before start, we would leave the conn
in a unbound but sort of started state where IO might be allowed even
though the drivers have been set in a state where they no longer expect
I/O.

4. Returning -EAGAIN in iscsi_if_destroy_conn if we haven't yet run the in
kernel stop_conn function is breaking userspace. We should have been doing
this for the caller.

Link: https://lore.kernel.org/r/20210525181821.7617-8-michael.christie@oracle.com
Fixes: 0ab710458d ("scsi: iscsi: Perform connection failure entirely in kernel space")
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:20 -04:00
Mike Christie
9e5fe17008 scsi: iscsi: Rel ref after iscsi_lookup_endpoint()
Subsequent commits allow the kernel to do ep_disconnect. In that case we
will have to get a proper refcount on the ep so one thread does not delete
it from under another.

Link: https://lore.kernel.org/r/20210525181821.7617-7-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:20 -04:00
Mike Christie
b25b957d2d scsi: iscsi: Use system_unbound_wq for destroy_work
Use the system_unbound_wq for async session destruction. We don't need a
dedicated workqueue for async session destruction because:

 1. perf does not seem to be an issue since we only allow 1 active work.

 2. it does not have deps with other system works and we can run them in
    parallel with each other.

Link: https://lore.kernel.org/r/20210525181821.7617-6-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:20 -04:00
Mike Christie
06c203a556 scsi: iscsi: Force immediate failure during shutdown
If the system is not up, we can just fail immediately since iscsid is not
going to ever answer our netlink events. We are already setting the
recovery_tmo to 0, but by passing stop_conn STOP_CONN_TERM we never will
block the session and start the recovery timer, because for that flag
userspace will do the unbind and destroy events which would remove the
devices and wake up and kill the eh.

Since the conn is dead and the system is going dowm this just has us use
STOP_CONN_RECOVER with recovery_tmo=0 so we fail immediately. However, if
the user has set the recovery_tmo=-1 we let the system hang like they
requested since they might have used that setting for specific reasons
(one known reason is for buggy cluster software).

Link: https://lore.kernel.org/r/20210525181821.7617-5-michael.christie@oracle.com
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:19 -04:00
Mike Christie
891e2639de scsi: iscsi: Stop queueing during ep_disconnect
During ep_disconnect we have been doing iscsi_suspend_tx/queue to block new
I/O but every driver except cxgbi and iscsi_tcp can still get I/O from
__iscsi_conn_send_pdu() if we haven't called iscsi_conn_failure() before
ep_disconnect. This could happen if we were terminating the session, and
the logout timed out before it was even sent to libiscsi.

Fix the issue by adding a helper which reverses the bind_conn call that
allows new I/O to be queued. Drivers implementing ep_disconnect can use this
to make sure new I/O is not queued to them when handling the disconnect.

Link: https://lore.kernel.org/r/20210525181821.7617-3-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-06-02 01:28:19 -04:00
Linus Torvalds
c98ff1d013 SCSI fixes on 20210417
This libsas fix is for a problem that occurs when trying to change the
 cache type of an ATA device and the libiscsi one is a regression fix
 from this merge window.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
 -----BEGIN PGP SIGNATURE-----
 
 iJwEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCYHuPRSYcamFtZXMuYm90
 dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pisha52AQCXc8n0
 6VAjfc+8aCqjX2Hpw4YCGeW5RYoNj1WXhiDv/AD+L4FVBMdQ4DE9ukH12YW7YBRS
 qP03aNSHLCl8wfVon8Q=
 =Btn4
 -----END PGP SIGNATURE-----

Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Two fixes: the libsas fix is for a problem that occurs when trying to
  change the cache type of an ATA device and the libiscsi one is a
  regression fix from this merge window"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: libsas: Reset num_scatter if libata marks qc as NODATA
  scsi: iscsi: Fix iSCSI cls conn state
2021-04-17 20:25:33 -07:00
Mike Christie
0dcf8febcb scsi: iscsi: Fix iSCSI cls conn state
In commit 9e67600ed6 ("scsi: iscsi: Fix race condition between login and
sync thread") I missed that libiscsi was now setting the iSCSI class state,
and that patch ended up resetting the state during conn stoppage and using
the wrong state value during ep_disconnect. This patch moves the setting of
the class state to the class module and then fixes the two issues above.

Link: https://lore.kernel.org/r/20210406171746.5016-1-michael.christie@oracle.com
Fixes: 9e67600ed6 ("scsi: iscsi: Fix race condition between login and sync thread")
Cc: Gulam Mohamed <gulam.mohamed@oracle.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-04-07 21:30:59 -04:00
Linus Torvalds
57fbdb15ec SCSI fixes on 20210402
Single fix to iscsi for a rare race condition which can cause a kernel
 panic.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
 -----BEGIN PGP SIGNATURE-----
 
 iJwEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCYGe3ZCYcamFtZXMuYm90
 dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pishaxZAQDt/zcv
 xvK+2qWNsqVse32hknc3RpdMWUh4JE1pKfSvgwD/X7c3goqQ8dEyEK0cpXLNpw9D
 kOOQxTVVCxFImwActdg=
 =VlUo
 -----END PGP SIGNATURE-----

Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fix from James Bottomley:
 "A single fix to iscsi for a rare race condition which can cause a
  kernel panic"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: iscsi: Fix race condition between login and sync thread
2021-04-03 09:07:35 -07:00
Gulam Mohamed
9e67600ed6 scsi: iscsi: Fix race condition between login and sync thread
A kernel panic was observed due to a timing issue between the sync thread
and the initiator processing a login response from the target. The session
reopen can be invoked both from the session sync thread when iscsid
restarts and from iscsid through the error handler. Before the initiator
receives the response to a login, another reopen request can be sent from
the error handler/sync session. When the initial login response is
subsequently processed, the connection has been closed and the socket has
been released.

To fix this a new connection state, ISCSI_CONN_BOUND, is added:

 - Set the connection state value to ISCSI_CONN_DOWN upon
   iscsi_if_ep_disconnect() and iscsi_if_stop_conn()

 - Set the connection state to the newly created value ISCSI_CONN_BOUND
   after bind connection (transport->bind_conn())

 - In iscsi_set_param(), return -ENOTCONN if the connection state is not
   either ISCSI_CONN_BOUND or ISCSI_CONN_UP

Link: https://lore.kernel.org/r/20210325093248.284678-1-gulam.mohamed@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Gulam Mohamed <gulam.mohamed@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

index 91074fd97f64..f4bf62b007a0 100644
2021-03-29 21:17:45 -04:00
Chris Leech
f9dbdf97a5 scsi: iscsi: Verify lengths on passthrough PDUs
Open-iSCSI sends passthrough PDUs over netlink, but the kernel should be
verifying that the provided PDU header and data lengths fall within the
netlink message to prevent accessing beyond that in memory.

Cc: stable@vger.kernel.org
Reported-by: Adam Nichols <adam@grimm-co.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 20:09:51 -05:00
Chris Leech
ec98ea7070 scsi: iscsi: Ensure sysfs attributes are limited to PAGE_SIZE
As the iSCSI parameters are exported back through sysfs, it should be
enforcing that they never are more than PAGE_SIZE (which should be more
than enough) before accepting updates through netlink.

Change all iSCSI sysfs attributes to use sysfs_emit().

Cc: stable@vger.kernel.org
Reported-by: Adam Nichols <adam@grimm-co.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 20:09:51 -05:00
Lee Duncan
688e8128b7 scsi: iscsi: Restrict sessions and handles to admin capabilities
Protect the iSCSI transport handle, available in sysfs, by requiring
CAP_SYS_ADMIN to read it. Also protect the netlink socket by restricting
reception of messages to ones sent with CAP_SYS_ADMIN. This disables
normal users from being able to end arbitrary iSCSI sessions.

Cc: stable@vger.kernel.org
Reported-by: Adam Nichols <adam@grimm-co.com>
Reviewed-by: Chris Leech <cleech@redhat.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-03-04 20:09:50 -05:00
Mike Christie
d39bfd0686 scsi: iscsi: Drop session lock in iscsi_session_chkready()
The session lock in iscsi_session_chkready() is not needed because when we
transition from logged into to another state we will block and/or remove
the devices under the session, so no new I/O will be sent to the drivers
after the block/remove. I/O that races with the block/removal is cleaned up
by the drivers when it handles all outstanding I/O, so this just added an
extra lock in the main I/O path. This patch removes the lock like other
transport classes.

Link: https://lore.kernel.org/r/20210207044608.27585-10-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2021-02-08 22:39:04 -05:00
Qinglang Miao
6dc1c7ab6f scsi: iscsi: Fix inappropriate use of put_device()
kfree(conn) is called inside put_device(&conn->dev) which could lead to
use-after-free. In addition, device_unregister() should be used here rather
than put_deviceO().

Link: https://lore.kernel.org/r/20201120074852.31658-1-miaoqinglang@huawei.com
Fixes: f3c893e3db ("scsi: iscsi: Fail session and connection on transport registration failure")
Reported-by: Hulk Robot <hulkci@huawei.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-12-07 17:45:19 -05:00
Linus Torvalds
dfdf16ecfd SCSI misc on 20200806
This series consists of the usual driver updates (ufs, qla2xxx, tcmu,
 lpfc, hpsa, zfcp, scsi_debug) and minor bug fixes.  We also have a
 huge docbook fix update like most other subsystems and no major update
 to the core (the few non trivial updates are either minor fixes or
 removing an unused feature [scsi_sdb_cache]).
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
 -----BEGIN PGP SIGNATURE-----
 
 iJwEABMIAEQWIQTnYEDbdso9F2cI+arnQslM7pishQUCXyxq1yYcamFtZXMuYm90
 dG9tbGV5QGhhbnNlbnBhcnRuZXJzaGlwLmNvbQAKCRDnQslM7pishSoAAQChZ4i8
 ZqYW3pL33JO3fA8vdjvLuyC489Hj4wzIsl3/bQEAxYyM6BSLvMoLWR2Plq/JmTLm
 4W/LDptarpTiDI3NuDc=
 =4b0W
 -----END PGP SIGNATURE-----

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This consists of the usual driver updates (ufs, qla2xxx, tcmu, lpfc,
  hpsa, zfcp, scsi_debug) and minor bug fixes.

  We also have a huge docbook fix update like most other subsystems and
  no major update to the core (the few non trivial updates are either
  minor fixes or removing an unused feature [scsi_sdb_cache])"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (307 commits)
  scsi: scsi_transport_srp: Sanitize scsi_target_block/unblock sequences
  scsi: ufs-mediatek: Apply DELAY_AFTER_LPM quirk to Micron devices
  scsi: ufs: Introduce device quirk "DELAY_AFTER_LPM"
  scsi: virtio-scsi: Correctly handle the case where all LUNs are unplugged
  scsi: scsi_debug: Implement tur_ms_to_ready parameter
  scsi: scsi_debug: Fix request sense
  scsi: lpfc: Fix typo in comment for ULP
  scsi: ufs-mediatek: Prevent LPM operation on undeclared VCC
  scsi: iscsi: Do not put host in iscsi_set_flashnode_param()
  scsi: hpsa: Correct ctrl queue depth
  scsi: target: tcmu: Make TMR notification optional
  scsi: target: tcmu: Implement tmr_notify callback
  scsi: target: tcmu: Fix and simplify timeout handling
  scsi: target: tcmu: Factor out new helper ring_insert_padding
  scsi: target: tcmu: Do not queue aborted commands
  scsi: target: tcmu: Use priv pointer in se_cmd
  scsi: target: Add tmr_notify backend function
  scsi: target: Modify core_tmr_abort_task()
  scsi: target: iscsi: Fix inconsistent debug message
  scsi: target: iscsi: Fix login error when receiving
  ...
2020-08-06 16:50:07 -07:00
Jing Xiangfeng
68e12e5f61 scsi: iscsi: Do not put host in iscsi_set_flashnode_param()
If scsi_host_lookup() fails we will jump to put_host which may cause a
panic. Jump to exit_set_fnode instead.

Link: https://lore.kernel.org/r/20200615081226.183068-1-jingxiangfeng@huawei.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-28 22:56:24 -04:00
Bob Liu
919a295abf scsi: iscsi: Register sysfs for workqueue iscsi_destroy
Register sysfs for workqueue iscsi_destroy so that users can set CPU
affinity through "cpumask" for this workqueue to get better isolation in
cloud multi-tenant scenario.

This patch unfolded create_singlethread_workqueue(), added WQ_SYSFS and
drop __WQ_ORDERED_EXPLICIT since __WQ_ORDERED_EXPLICIT workqueue isn't
allowed to change "cpumask".

Link: https://lore.kernel.org/r/20200703051603.1473-1-bob.liu@oracle.com
Suggested-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-08 00:18:51 -04:00
Mike Christie
93bf02e5a2 scsi: iscsi: Remove sessdestroylist
Just delete the sess from the session list instead of adding it to some
list we never use.

Link: https://lore.kernel.org/r/1593632868-6808-4-git-send-email-michael.christie@oracle.com
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-02 23:46:15 -04:00
Mike Christie
1d726aa6ef scsi: iscsi: Optimize work queue flush use
There is no need for one session to flush the entire iscsi_eh_timer_workq
when removing/unblocking a session. During removal we need to make sure our
works are not running anymore. And iscsi_unblock_session only needs to make
sure its work is done. The unblock work function will flush/cancel the
works it has conflicts with.

Link: https://lore.kernel.org/r/1593632868-6808-3-git-send-email-michael.christie@oracle.com
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-02 23:46:14 -04:00
Mike Christie
e463f96bdc scsi: iscsi: Delay freeing target_id
If we are doing async removal of the session, we could be doing a
scsi_remove_target from the removal workqueue, and for the offload case we
could be doing a new session addition and scan to the same host. The
add/scan might then end up trying to use the target_id of the target we are
removing.

This patch just has a delay the freeing of the target_id until after the
scsi_remove_target has completed, so we know it's no longer in use.

Link: https://lore.kernel.org/r/1593632868-6808-2-git-send-email-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-02 23:46:14 -04:00
Bob Liu
1a98262041 scsi: iscsi: Change iSCSI workqueue max_active back to 1
Commit 3ce419662d ("scsi: iscsi: Register sysfs for iscsi workqueue")
enabled 'cpumask' support for iSCSI workqueues. However, it is unnecessary
to set max_active = 2 since 'cpumask' can still be modified when max_active
is 1.

This patch sets max_active to 1 so as to keep the same behaviour as before.

Link: https://lore.kernel.org/r/20200701030745.16897-1-bob.liu@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-07-02 23:13:54 -04:00
Gabriel Krisman Bertazi
7e7cd796f2 scsi: iscsi: Fix deadlock on recovery path during GFP_IO reclaim
iSCSI suffers from a deadlock in case a management command submitted via
the netlink socket sleeps on an allocation while holding the rx_queue_mutex
if that allocation causes a memory reclaim that writebacks to a failed
iSCSI device.  The recovery procedure can never make progress to recover
the failed disk or abort outstanding IO operations to complete the reclaim
(since rx_queue_mutex is locked), thus locking the system.

Nevertheless, just marking all allocations under rx_queue_mutex as GFP_NOIO
(or locking the userspace process with something like PF_MEMALLOC_NOIO) is
not enough, since the iSCSI command code relies on other subsystems that
try to grab locked mutexes, whose threads are GFP_IO, leading to the same
deadlock. One instance where this situation can be observed is in the
backtraces below, stitched from multiple bugs reports, involving the kobj
uevent sent when a session is created.

The root of the problem is not the fact that iSCSI does GFP_IO allocations,
that is acceptable. The actual problem is that rx_queue_mutex has a very
large granularity, covering every unrelated netlink command execution at
the same time as the error recovery path.

The proposed fix leverages the recently added mechanism to stop failed
connections from the kernel, by enabling it to execute even though a
management command from the netlink socket is being run (rx_queue_mutex is
held), provided that the command is known to be safe.  It splits the
rx_queue_mutex in two mutexes, one protecting from concurrent command
execution from the netlink socket, and one protecting stop_conn from racing
with other connection management operations that might conflict with it.

It is not very pretty, but it is the simplest way to resolve the deadlock.
I considered making it a lock per connection, but some external mutex would
still be needed to deal with iscsi_if_destroy_conn.

The patch was tested by forcing a memory shrinker (unrelated, but used
bufio/dm-verity) to reclaim iSCSI pages every time
ISCSI_UEVENT_CREATE_SESSION happens, which is reasonable to simulate
reclaims that might happen with GFP_KERNEL on that path.  Then, a faulty
hung target causes a connection to fail during intensive IO, at the same
time a new session is added by iscsid.

The following stacktraces are stiches from several bug reports, showing a
case where the deadlock can happen.

 iSCSI-write
         holding: rx_queue_mutex
         waiting: uevent_sock_mutex

         kobject_uevent_env+0x1bd/0x419
         kobject_uevent+0xb/0xd
         device_add+0x48a/0x678
         scsi_add_host_with_dma+0xc5/0x22d
         iscsi_host_add+0x53/0x55
         iscsi_sw_tcp_session_create+0xa6/0x129
         iscsi_if_rx+0x100/0x1247
         netlink_unicast+0x213/0x4f0
         netlink_sendmsg+0x230/0x3c0

 iscsi_fail iscsi_conn_failure
         waiting: rx_queue_mutex

         schedule_preempt_disabled+0x325/0x734
         __mutex_lock_slowpath+0x18b/0x230
         mutex_lock+0x22/0x40
         iscsi_conn_failure+0x42/0x149
         worker_thread+0x24a/0xbc0

 EventManager_
         holding: uevent_sock_mutex
         waiting: dm_bufio_client->lock

         dm_bufio_lock+0xe/0x10
         shrink+0x34/0xf7
         shrink_slab+0x177/0x5d0
         do_try_to_free_pages+0x129/0x470
         try_to_free_mem_cgroup_pages+0x14f/0x210
         memcg_kmem_newpage_charge+0xa6d/0x13b0
         __alloc_pages_nodemask+0x4a3/0x1a70
         fallback_alloc+0x1b2/0x36c
         __kmalloc_node_track_caller+0xb9/0x10d0
         __alloc_skb+0x83/0x2f0
         kobject_uevent_env+0x26b/0x419
         dm_kobject_uevent+0x70/0x79
         dev_suspend+0x1a9/0x1e7
         ctl_ioctl+0x3e9/0x411
         dm_ctl_ioctl+0x13/0x17
         do_vfs_ioctl+0xb3/0x460
         SyS_ioctl+0x5e/0x90

 MemcgReclaimerD"
         holding: dm_bufio_client->lock
         waiting: stuck io to finish (needs iscsi_fail thread to progress)

         schedule at ffffffffbd603618
         io_schedule at ffffffffbd603ba4
         do_io_schedule at ffffffffbdaf0d94
         __wait_on_bit at ffffffffbd6008a6
         out_of_line_wait_on_bit at ffffffffbd600960
         wait_on_bit.constprop.10 at ffffffffbdaf0f17
         __make_buffer_clean at ffffffffbdaf18ba
         __cleanup_old_buffer at ffffffffbdaf192f
         shrink at ffffffffbdaf19fd
         do_shrink_slab at ffffffffbd6ec000
         shrink_slab at ffffffffbd6ec24a
         do_try_to_free_pages at ffffffffbd6eda09
         try_to_free_mem_cgroup_pages at ffffffffbd6ede7e
         mem_cgroup_resize_limit at ffffffffbd7024c0
         mem_cgroup_write at ffffffffbd703149
         cgroup_file_write at ffffffffbd6d9c6e
         sys_write at ffffffffbd6662ea
         system_call_fastpath at ffffffffbdbc34a2

Link: https://lore.kernel.org/r/20200520022959.1912856-1-krisman@collabora.com
Reported-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-26 21:20:24 -04:00