In case a client fails to connect in mei_cldev_enable(), the
caller won't call the mei_cldev_disable leaving the client
in a linked stated. Upon driver unload the client structure
will be freed in mei_cl_bus_dev_release(), leaving a stale pointer
on a fail_list. This will eventually end up in crash
during power down flow in mei_cl_set_disonnected().
RIP: mei_cl_set_disconnected+0x5/0x260[mei]
Call trace:
mei_cl_all_disconnect+0x22/0x30
mei_reset+0x194/0x250
__synchronize_hardirq+0x43/0x50
_cond_resched+0x15/0x30
mei_me_intr_clear+0x20/0x100
mei_stop+0x76/0xb0
mei_me_shutdown+0x3f/0x80
pci_device_shutdown+0x34/0x60
kernel_restart+0x0e/0x30
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200455
Fixes: 'c110cdb17148 ("mei: bus: make a client pointer always available")'
Cc: <stable@vger.kernel.org> 4.10+
Tested-by: Georg Müller <georgmueller@gmx.net>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case the device is not connected it doesn't 'get'
hw module and hence should not 'put' it on disable.
Cc: <stable@vger.kernel.org> 4.16+
Fixes:'commit 257355a44b ("mei: make module referencing local to the bus.c")'
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200455
Tested-by: Georg Müller <georgmueller@gmx.net>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add optional timeout to internal bus recv function to
enable break out of internal flows in case of no answer from FW.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Limit the number of queued writes per client.
Writes above this threshold are blocked till place
in the transmit queue is available.
The limit is configurable via sysfs and defaults to 50.
The implementation should provide blocking I/O behavior.
Prior to this change one would end up in the hands of OOM.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Module reference counting is relevant only to the
mei client devices. Make the implementation clean
and move it to bus.c
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes regression introduced by
commit 8d52af6795 ("mei: speed up the power down flow")
In mei_cldev_disable during device power down flow, such as
suspend or system power off, it jumps over disconnecting function
to speed up the power down process, however, because the client is
unlinked from the file_list (mei_cl_unlink) mei_cl_set_disconnected
is not called from mei_cl_all_disconnect leaving resource leaking.
The most visible is reference counter on underlying HW module is
not decreased preventing to remove modules after suspend/resume cycles.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Fixes: 8d52af6795 ("mei: speed up the power down flow")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Trivial fix to spelling mistake in dev_dbg debug message. Also
add in a missing comma.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When mei driver is powering down due to suspend or shutdown
it will iterate over the mei client bus and disconnect
each client device attached in turn.
The power down flow consist of the link rest, which causes all clients
get disconnected at once, hence the individual disconnection
can be omitted and significantly reduce power down flow.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make this const as it is only stored in the type field of a device
structure, which is const.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
modprobe is not able to resolve sysfs modalias for mei devices.
# cat
/sys/class/watchdog/watchdog0/device/watchdog/watchdog0/device/modalias
mei::05b79a6f-4628-4d7f-899d-a91514cb32ab:
# modprobe --set-version 4.9.6-200.fc25.x86_64 -R
mei::05b79a6f-4628-4d7f-899d-a91514cb32ab:
modprobe: FATAL: Module mei::05b79a6f-4628-4d7f-899d-a91514cb32ab: not
found in directory /lib/modules/4.9.6-200.fc25.x86_64
# cat /lib/modules/4.9.6-200.fc25.x86_64/modules.alias | grep
05b79a6f-4628-4d7f-899d-a91514cb32ab
alias mei:*:05b79a6f-4628-4d7f-899d-a91514cb32ab:*:* mei_wdt
commit b26864cad1 ("mei: bus: add client protocol
version to the device alias"), however sysfs modalias
is still in formmat mei:S:uuid:*.
This patch equates format of uevent and sysfs modalias so that modprobe
is able to resolve the aliases.
Cc: <stable@vger.kernel.org> 4.7+
Fixes: commit b26864cad1 ("mei: bus: add client protocol version to the device alias")
Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mei_cl_bus_rescan is used only in bus.c,
so make it local to the file and mark static.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
AMTHIF has special support in the mei drive, it handles multiplexing
multiple user space connection above single me client connection.
Since there is no additional addressing information there is a strict
requirement on the traffic order on each connection and on the "read
after write" order within the connection. This creates a lot of
complexity mostly because the other client types do not necessarily fall
under the same restriction. After carefully studying the use of the
AMTHIF client, we came to conclusion that the multiplexing is not really
utilized by any application and we may safely remove that support and
significantly simplify the driver.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Stop and unregister receive and notification callbacks
from the disable function, to allow its later re-enablement.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The hardware module should not be unloaded if the bus
has active devices.
Get get_/put_ bus parent module upon client device
connection/disconnection, to prevent the hardware managing
module to disappear underneath.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A driver on the mei bus may rely on the availability
of the receive callback during driver remove() call, e.g. mei_wdt.
Move callbacks dismantling after the remove() call to unblock that scenario.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adjust function name in KDoc.
Fixes: d49dc5e76f (mei: bus: use mei_cldev_ prefix for the API functions)
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enable non-blocking receive for drivers on mei bus, this allows checking
for data availability by mei client drivers. This is most effective for
fixed address clients, that lacks flow control.
This function adds new API function mei_cldev_recv_nonblock(), it
retuns -EGAIN if function will block.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Split callbacks for RX and async notification events on mei bus to
eliminate synchronization problems and to open way for RX optimizations.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change life time of the client pointer, allocate it upon client device
creation and free it upon device destruction, instead of upon
connection and disconnection.
This helps to eliminate racy NULL checks in the bus code.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Prepare the client write functions to set the internal flag in message
header. Carry both blocking and internal modes inside the transmit cb,
and call internal bus function __mei_cl_send() with send mode bit mask.
The Internal flag should be added only on messages generated by the
driver.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A mei client driver on the mei client bus can call disconnect function on
already internal disconnected client. A client can disconnect internally,
for example, during link reset or upon FW request. Those are legitimate
flows and we should not log an error message, hence we demote
'Already disconnected' message to the debug level.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The callback context is redunant as all the information can be
retrived from the device struture of its private data.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The device lock was unnecessary obtained in bus rescan work before the
amthif client search. That causes incorrect lock ordering and task
hang:
...
[88004.613213] INFO: task kworker/1:14:21832 blocked for more than 120 seconds.
...
[88004.645934] Workqueue: events mei_cl_bus_rescan_work
...
The correct lock order is
cl_bus_lock
device_lock
me_clients_rwsem
Move device_lock into amthif init function that called
after me_clients_rwsem is released.
This fixes regression introduced by commit:
commit 025fb792ba ("mei: split amthif client init from end of clients enumeration")
Cc: <stable@vger.kernel.org> # 4.6+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enclose the boiler plate code of allocating a control/hbm command cb
and enqueueing it onto ctrl_wr.list in a convenient wrapper
mei_cl_enqueue_ctrl_wr_cb().
This is a preparatory patch for enabling consecutive reads.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Correct errno on client disconnection is -ENODEV not -EBUSY
Cc: <stable@vger.kernel.org> #4.3+
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the course of the read flow we want to wait for read completion only
if the read queue is empty.
However the calling list_empty(&cl->rd_completed) is a duplication as the
same check was performed by mei_cl_read_cb() and the waiting is skipped
if it returns not NULL.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Ensure that mei_cl_read_start is called under the device lock
also in the bus layer. The function updates global ctrl_wr_list
which should be locked.
Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If cldrv->probe() failed in mei_cl_device_probe(),
the mei module is left pinned.
The patch moves __module_get(THIS_MODULE) after cldrv->probe().
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's no reason to duplicate the logic provided by scnprintf().
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix double freeing of the cb that can happen if link reset kicks in the
middle of blocked write from a device on the cl bus.
Free cb inside mei_cl_write function on failure and drop cb free
operation from callers, during a link reset the mei_cl_write function
returns with an error, but the caller doesn't know if the cb was
already queued or not so it doesn't know if the cb will be freed upon
queue reclaim or it has to free it itself.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The amthif FW client can appear after the end of client enumeration.
Amthif host client initialization is done now at FW client discovery
time.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since clients can be now added and removed during runtime
we need to run bus rescan whenever me_clients list is modified.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The reserved host clients can be obsoleted now, a portion of the
platforms is shipped without iAMT enabled, where the reservation is not
relevant and for platforms with iAMT dynamic allocation is sufficient.
Dropping reserved ids makes enumeration more flexible and generic
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The bus data transfer interface was missing the check if the device is
in enabled state, this may lead to stack corruption during link reset.
Cc: <stable@vger.kernel.org> #4.0
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Call wake_up cl->ev_wait only in case there is no bus client registered
to the event notification.
Second, since we don't have exclusive waiter wake_up_interruptible_all
is not used correctly here.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In this particular case this more correct and safer to check if the RX
event is set in the event mask rather than query waitqueue_active
Since the check is already performed in the mei_cl_bus_rx_event
function, it is just required to check for its return value.
Second, since we don't have exclusive waiter wake_up_interruptible_all
is not used correctly here.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The mei bus fixup use dev_xxx services for printing
to kernel log so we need to setup the device name
prior to running fixup hooks.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
s/send/receive/
The buffer in the receive function is
not used for sending
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use mei_cl_bus_ for internal bus function consistently.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use mei_cldev_ prefix for all mei client bus api functions
in order to resolve prefix conflict with functions that handle
client function and are defined in client.c
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Let me client device driver query of the device is connected
and hence enabled.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Export the uuid and the protocol version of the underlying me client
for me client bus drivers usage.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The device alias now looks like mei:S:uuid:N:*
In that way we can bind different drivers to clients with
different protocol versions if required.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
export me client protocol version to sysfs and uevent
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
scripts/mod/file2alias.c:add_uuid() convert UUID into a single string
which does not conform to the standard little endian UUID formatting.
This patch changes add_uuid() to output same format as %pUL and modifies
the mei driver to match the change.
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Enable drivers on mei client bus to subscribe
to asynchronous event notifications.
Introduce events_mask to the existing callback infrastructure
so it is possible to handle both RX and event notification.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
MEI bus was designed around nfc and was hard to extend.
Instead of the hard coded way of adding the devices on the mei bus
we scan the whole me client list and create a device for each
eligible me client (mei_cl_bus_rescan); currently we support
only clients with single connection and fixed address clients.
NFC radio name detection is run as a fixup routine
The patch replaces handling the device list based on struct me_cl
to device list based on me_cl_devices. The creating a connection
is pushed from the device creation time to device enablement.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tomas Winkler