Kill off the concept of maintaining a bundle of connections to a particular
target service to increase the number of call slots available for any
beyond four for that service (there are four call slots per connection).
This will make cleaning up the connection handling code easier and
facilitate removal of the rxrpc_transport struct. Bundling can be
reintroduced later if necessary.
Signed-off-by: David Howells <dhowells@redhat.com>
Provide refcount helper functions for connections so that the code doesn't
touch local or connection usage counts directly.
Also make it such that local and peer put functions can take a NULL
pointer.
Signed-off-by: David Howells <dhowells@redhat.com>
Make rxrpc_send_packet() take a connection not a transport as part of the
phasing out of the rxrpc_transport struct.
Whilst we're at it, rename the function to rxrpc_send_data_packet() to
differentiate it from the other packet sending functions.
Signed-off-by: David Howells <dhowells@redhat.com>
Allocated rxrpc calls displayed in /proc/net/rxrpc_calls may in future be
on the proc list before they're connected or after they've been
disconnected - in which case they may not have a pointer to a connection
struct that can be used to get data from there.
Deal with this by using stuff from the call struct in preference where
possible and printing "no_connection" rather than a peer address if no
connection is assigned.
This change also has the added bonus that the service ID is now taken from
the call rather the connection which will allow per-call service upgrades
to be shown - something required for AuriStor server compatibility.
Signed-off-by: David Howells <dhowells@redhat.com>
Validate the net address given to rxrpc_kernel_begin_call() before using
it.
Whilst this should be mostly unnecessary for in-kernel users, it does clear
the tail of the address struct in case we want to hash or compare the whole
thing.
Signed-off-by: David Howells <dhowells@redhat.com>
Use the IDR facility to allocate client connection IDs on a machine-wide
basis so that each client connection has a unique identifier. When the
connection ID space wraps, we advance the epoch by 1, thereby effectively
having a 62-bit ID space. The IDR facility is then used to look up client
connections during incoming packet routing instead of using an rbtree
rooted on the transport.
This change allows for the removal of the transport in the future and also
means that client connections can be looked up directly in the data-ready
handler by connection ID.
The ID management code is placed in a new file, conn-client.c, to which all
the client connection-specific code will eventually move.
Note that the IDR tree gets very expensive on memory if the connection IDs
are widely scattered throughout the number space, so we shall need to
retire connections that have, say, an ID more than four times the maximum
number of client conns away from the current allocation point to try and
keep the IDs concentrated. We will also need to retire connections from an
old epoch.
Also note that, for the moment, a pointer to the transport has to be passed
through into the ID allocation function so that we can take a BH lock to
prevent a locking issue against in-BH lookup of client connections. This
will go away later when RCU is used for server connections also.
Signed-off-by: David Howells <dhowells@redhat.com>
rxrpc_connection_lock shouldn't be accessed as a BH-excluding lock. It's
only accessed in a few places and none of those are in BH-context.
rxrpc_transport::conn_lock, however, *is* a BH-excluding lock and should be
accessed so consistently.
Signed-off-by: David Howells <dhowells@redhat.com>
Pass a pointer to struct sk_buff rather than struct rxrpc_host_header to
functions so that they can in the future get at transport protocol parameters
rather than just RxRPC parameters.
Signed-off-by: David Howells <dhowells@redhat.com>
"Exclusive connections" are meant to be used for a single client call and
then scrapped. The idea is to limit the use of the negotiated security
context. The current code, however, isn't doing this: it is instead
restricting the socket to a single virtual connection and doing all the
calls over that.
This is changed such that the socket no longer maintains a special virtual
connection over which it will do all the calls, but rather gets a new one
each time a new exclusive call is made.
Further, using a socket option for this is a poor choice. It should be
done on sendmsg with a control message marker instead so that calls can be
marked exclusive individually. To that end, add RXRPC_EXCLUSIVE_CALL
which, if passed to sendmsg() as a control message element, will cause the
call to be done on an single-use connection.
The socket option (RXRPC_EXCLUSIVE_CONNECTION) still exists and, if set,
will override any lack of RXRPC_EXCLUSIVE_CALL being specified so that
programs using the setsockopt() will appear to work the same.
Signed-off-by: David Howells <dhowells@redhat.com>
Replace accesses of conn->trans->{local,peer} with
conn->params.{local,peer} thus making it easier for a future commit to
remove the rxrpc_transport struct.
This also reduces the number of memory accesses involved.
Signed-off-by: David Howells <dhowells@redhat.com>
Define and use a structure to hold connection parameters. This makes it
easier to pass multiple connection parameters around.
Define and use a structure to hold protocol information used to hash a
connection for lookup on incoming packet. Most of these fields will be
disposed of eventually, including the duplicate local pointer.
Whilst we're at it rename "proto" to "family" when referring to a protocol
family.
Signed-off-by: David Howells <dhowells@redhat.com>
Hashing the peer key was introduced for AF_INET, but gcc
warns about the rxrpc_peer_hash_key function returning uninitialized
data for any other value of srx->transport.family:
net/rxrpc/peer_object.c: In function 'rxrpc_peer_hash_key':
net/rxrpc/peer_object.c:57:15: error: 'p' may be used uninitialized in this function [-Werror=maybe-uninitialized]
Assuming that nothing else can be set here, this changes the
function to just return zero in case of an unknown address
family.
Fixes: be6e6707f6 ("rxrpc: Rework peer object handling to use hash table and RCU")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David Howells <dhowells@redhat.com>
rxrpc_lookup_peer_rcu() and rxrpc_lookup_peer() return NULL on error, never
error pointers, so IS_ERR() can't be used.
Fix three callers of those functions.
Fixes: be6e6707f6 ('rxrpc: Rework peer object handling to use hash table and RCU')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Some systems need current frequency from last_status for calculation
but it is zeroed during initialization. When the device starts there is
no history, but we can assume that the last frequency was the
same as the initial frequency (which is also used in 'previous_freq').
The log shows the result of this misinterpreted value.
[ 2.042847] ... Failed to get voltage for frequency 0: -34
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Smatch complains because platform_get_resource() returns NULL on error
and not an error pointer so the check is wrong. Julia Lawall pointed
out that normally we don't check these, because devm_ioremap_resource()
has a check for NULL.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
When device_register() returns with error, it has already
done put_device() on the input device pointer.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
devm_kzalloc of devfreq's statistics data structure has been
using its parent device as the dev allocated for.
If a device's devfreq is disabled in run-time,
such allocated memory won't be freed.
Desginating more precisely with the devfreq device
pointer fixes the issue.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
The new module-level code (MLC) approach invokes MLC on the per-table
basis, but the dynamic loading support of this is incorrect because
of the lock order:
acpi_ns_evaluate
acpi_ex_enter_intperter
acpi_ns_load_table (triggered by Load opcode)
acpi_ns_exec_module_code_list
acpi_ex_enter_intperter
The regression is introduced by the following commit:
Commit: 2785ce8d0d
ACPICA Commit: 071eff738c59eda1792ac24b3b688b61691d7e7c
Subject: ACPICA: Add per-table execution of module-level code
This patch fixes this regression by unlocking the interpreter lock
before invoking MLC. However, the unlocking is done to the
acpi_ns_load_table(), in which the interpreter lock should be locked
by acpi_ns_parse_table() but it wasn't.
Fixes: 2785ce8d0d (ACPICA: Add per-table execution of module-level code)
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 4.5+ <stable@vger.kernel.org> # 4.5+
[ rjw : Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
__sync_icache_dcache unconditionally skips the cache maintenance for
anonymous pages, under the assumption that flushing is only required in
the presence of D-side aliases [see 7249b79f6b ("arm64: Do not flush
the D-cache for anonymous pages")].
Unfortunately, this breaks migration of anonymous pages holding
self-modifying code, where userspace cannot be reasonably expected to
reissue maintenance instructions in response to a migration.
This patch fixes the problem by removing the broken page_mapping(page)
check from the cache syncing code, otherwise we may end up fetching and
executing stale instructions from the PoU.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
I fixed boot image dependencies for arch/arm in commit 3939f33450
("ARM: 8418/1: add boot image dependencies to not generate invalid
images").
I see a similar problem for arch/arm64; "make -jN Image Image.gz"
would sometimes end up generating bad images where N > 1.
Fix the dependency in arch/arm64/Makefile to avoid the race
between "make Image" and "make Image.*".
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
During a rollover, we mark the active ASID on each CPU as reserved, before
allocating a new ID for the task that caused the rollover. This means that
with N CPUs, we can only guarantee the new task to obtain a valid ASID if
we have at least N+1 ASIDs. Update this limit in the initcall check.
Note that this restriction was introduced by commit 8e648066 on the
arch/arm side, which disallow re-using the previously active ASID on the
local CPU, as it would introduce a TLB race.
In addition, we only dispose of NUM_USER_ASIDS-1, since ASID 0 is
reserved. Add this restriction as well.
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
>From https://bugs.freedesktop.org/show_bug.cgi?id=96461 :
This was kind of a difficult bug to track down. If you're using a
Haswell system running GNOME and you have fbc completely enabled and
working, playing videos can result in video artifacts. Steps to
reproduce:
- Run GNOME
- Ensure FBC is enabled and active
- Download a movie, I used the ogg version of Big Buck Bunny for this
- Run `gst-launch-1.0 filesrc location='some_movie.ogg' ! decodebin !
glimagesink` in a terminal
- Watch for about over a minute, you'll see small horizontal lines go
down the screen.
For the time being, disable FBC for Haswell by default.
Stefan Richter reported kernel freezes (no video artifacts) when fbc
is on. (E3-1245 v3 with HD P4600; openbox and some KDE and LXDE
applications, thread begins at https://lkml.org/lkml/2016/4/26/813).
We also got reports from Steven Honeyman on openbox+roxterm.
v2 (From Paulo):
- Add extra information to the commit message
- Add Fixes tag
- Rebase
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96461
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96464
Fixes: a98ee79317 ("drm/i915/fbc: enable FBC by default on HSW and BDW")
Cc: stable@vger.kernel.org
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1465487895-7401-1-git-send-email-cpaul@redhat.com
(cherry picked from commit c7f7e2feff)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
It has been found out that in some HW combination the DisplayPort
fast link training feature caused screen flickering. Let's revert
this feature for now until we can ensure that the feature works for
all platforms.
This is a manual revert of commits 5fa836a9d8 ("drm/i915: DP link
training optimization") and 4e96c97742 ("drm/i915: eDP link training
optimization").
Fixes: 5fa836a9d8 ("drm/i915: DP link training optimization")
Fixes: 4e96c97742 ("drm/i915: eDP link training optimization")
Cc: <stable@vger.kernel.org> # v4.2+
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91393
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1466410226-19543-1-git-send-email-mika.kahola@intel.com
(cherry picked from commit 91df09d92a)
Power saving feature which reduces the amount of
voltage needed for specific engine clocks.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
avfs feature is for voltage control based on
gpu system clock on polaris10
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
To minimize the dram power expenditure during static -screen
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
sync up with internal programming recommendations.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Missing pcie dpm settings.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Ken Wang <Qingqing.Wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
before request performance state.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Ken Wang <Qingqing.Wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Wrong value passed to acpi_pcie_perf_request.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Ken Wang <Qingqing.Wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
the error lead powerplay can't get display info in DGPU case.
store_cc6_data just implement in APU.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
atmel_hlcdc_create_outputs() iterates over OF graph nodes and releases
the node (using of_node_put()) after each iteration, which is wrong
since for_each_endpoint_of_node() is already taking care of that.
Move the of_node_put() call in the error path.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Fixes: 17a8e03e7e ("drm: atmel-hlcdc: rework the output code to support drm bridges")
The driver is only enabling scaling, but never disabling it, thus, if you
enable the scaling feature once it stays enabled forever.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Alex Vazquez <avazquez.dev@gmail.com>
Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Fixes: 1a396789f6 ("drm: add Atmel HLCDC Display Controller support")
Cc: <stable@vger.kernel.org>
Jiri Pirko says:
====================
mlxsw: Preparation for IPv4 router
Ido says:
This series prepares the driver for IPv4 router support. The router follow-up
patches are available at: https://github.com/jpirko/linux_mlxsw/tree/net-next_queue
Patches 1-9 simplify the netdevice notification block and also add several
checks during PRECHANGEUPPER events against topologies that aren't supported by
the device. This will ensure L3 interfaces are only configured on top of
valid netdevs.
Patches 10-13 contain trivial changes required for the introduction of a generic
FID struct - currently only used for vFIDs - in patch 14. Making the FID
struct generic will allow us to easily associate the underlying FIDs with
their L3-counterparts - Router interfaces (RIFs):
FID Type | Used by | RIF Type
--------------------------------------------------------
FID | The VLAN-aware bridge | VLAN
vFID | VLAN-unaware bridges | FID
rFID | non-bridged netdevs (follow-up) | Sub-port
Obligatory ASCII art to visualize the above:
A.B.C.D
+
| FID RIF
+
br0 E.F.G.H
+ +
| | VLAN RIF
+---------+---------+ +
| | br1.W
| vFID | +
| | |
vPort +-+-+ +-+-+ +
swXpY.Z | | | | br1
+-+-+ +-+-+ +
| | FID=W |
| | +------------+------------+
| | | |
+---+---+ +---+-+-+ +---+---+
| | | | | |
| | | | | |
| | | | | |
+-------+ +-------+ +-------+
swXpY
Patches 15-16 further generalize the struct by exploiting the fact that the
FID is a shared resource among ports. Each FID type is assigned a 'leave'
function that is invoked based on CHANGEUPPER events and takes care of the
necessary clean-up.
Patches 17-22 build upon the previous patches and use the FID struct for the
VLAN-aware bridge and take care of cleaning up FID resources in the 'leave'
functions. For now, these are only FDB records, but later on we'll have to
remove the RIFs associated with these FIDs, which will in turn take care of
routes and neighbours clean-up.
The last patch adds debug prints that proved very useful during the
development of this series.
Tested with the existing L2 recipes:
https://github.com/jpirko/lnst/tree/master/recipes/switchdev
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
For debug purposes, it's useful to know the order in which the driver
responds to changes in the topology of its upper devices.
Add debug prints to signal these events.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are situations in which a vPort is destroyed while still holding
references to device's resources such as FIDs and FDB records. This can
happen, for example, when a VLAN device is deleted while still being
bridged.
Instead of trying to make sure vPort destruction is invoked when it no
longer uses device's resources, just free them upon destruction. This
simplifies the code, as we no longer need to take different situations
into account when events are received - cleanup is taken care of in one
place.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
FDB entries are learned using {Port / LAG ID, FID} and therefore should
be flushed whenever a port (vPort) leaves its FID (vFID).
However, when the bridge port is a LAG device (or a VLAN device on top),
then FDB flushing is conditional. Ports removed from such LAG
configurations must not trigger flushing, as other ports might still be
members in the LAG and therefore the bridge port is still active.
The decision whether to flush or not was previously computed in the
netdevice notification block, but in order to flush the entries when a
port leaves its FID this decision should be computed there.
Strip the notification block from this logic and instead move it to one
FDB flushing function that is invoked from both the FID / vFID leave
functions.
When port isn't member in LAG, FDB flushing should always occur.
Otherwise, it should occur only when the last port (vPort) member in the
LAG leaves the FID (vFID).
This will allow us - in the next patch - to simplify the cleanup code
paths that are hit whenever the topology above the port netdevs changes.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Not all vPorts will have FIDs assigned to them, so make sure functions
first test for FID presence.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As previously explained, not all vPorts will be assigned FIDs, so instead
of returning the FID index of a vPort, return a pointer to its FID
struct. This will allow us to know whether it's legal to access the
vPort's FID parameters such as index and device.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When L3 interfaces will be introduced a vPort won't necessarily have a
FID assigned to it. This can happen if it's not member in a bridge (in
which case it's assigned a vFID) or doesn't have an IP address (in which
case it's assigned an rFID).
Therefore, instead check the VID parameter to test whether a port is a
vPort or not.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a very similar way to the vFIDs, make the first 4K FIDs - used in the
VLAN-aware bridge - use the new FID struct.
Upon first use of the FID by any of the ports do the following:
1) Create the FID
2) Setup a matching flooding entry
3) Create a mapping for the FID
Unlike vFIDs, upon creation of a FID we always create a global
VID-to-FID mapping, so that ports without upper vPorts can use it
instead of creating an explicit {Port, VID} to FID mapping.
When a port leaves a FID the reverse is performed. Whenever the FID's
reference count reaches zero the FID is deleted along with the global
mapping.
The per-FID struct will later allow us to configure L3 interfaces on top
of the VLAN-aware bridge.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a vPort is created or when it joins a bridge we always do the same
set of operations:
1) Create the vFID, if not already created
2) Setup flooding for the vFID
3) Map the {Port, VID} to the vFID
When a vPort is destroyed or when it leaves a bridge the reverse is
performed.
Encapsulate the above in join / leave functions and simplify the code.
FIDs and rFIDs will use a similar set of functions.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Up until now we had a dedicated struct only for vFIDs, but before
introducing support for L3 interfaces we need to make it generic and
use it for all three types of FIDs:
1) FIDs - 0..4K-1, used for the VLAN-aware bridge
2) vFIDs - 4K..15K-1, used for VLAN-unaware bridges
3) rFIDs - 15K..16K-1, used to direct traffic to / from the router in
the device. Will be introduced later in the series.
The three types of L3 interfaces - Router InterFaces, RIFs - that will
be introduced correspond to the three types of FIDs and are configured
using them. Therefore, we'll need to store the links between them as
well as a reference count on the underlying FID, so that the
corresponding RIF will be destroyed when it reaches zero.
Note that the lower 0.5K vFIDs are currently used for for non-bridged
netdevs, so that traffic could be flooded to the CPU port. However, when
rFIDs will be introduced we'll no longer need these and they too will be
used for VLAN-unaware bridges.
Make the vFID struct generic by renaming it and some of its fields. FIDs
will be converted to use it later in the series.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>