virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after restore returns, virtio net violated this
rule by using receive VQs within restore.
To fix, call virtio_device_ready before using VQs.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after resume returns, virtio console violated this
rule by adding inbufs, which causes the VQ to be used directly within
restore.
To fix, call virtio_device_ready before using VQs.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after restore returns, virtio scsi violated
this rule on restore by kicking event vq within restore.
To fix, call virtio_device_ready before using event queue.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after restore returns, virtio block violated
this rule on restore by restarting queues, which might in theory
cause the VQ to be used directly within restore.
To fix, call virtio_device_ready before using starting queues.
virtio_net: fix use after free on allocation failure
In the extremely unlikely event that driver initialization fails after
RX buffers are added, virtio net frees RX buffers while VQs are
still active, potentially causing device to use a freed buffer.
To fix, reset device first - same as we do on device removal.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, but virtio 9p device
adds self to channel list within probe, at which point VQ can be
used in violation of the spec.
To fix, call virtio_device_ready before using VQs.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, virtio console violated this
rule by adding inbufs, which causes the VQ to be used directly within
probe.
To fix, call virtio_device_ready before using VQs.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, virtio block violated this
rule by calling add_disk, which causes the VQ to be used directly within
probe.
To fix, call virtio_device_ready before using VQs.
virtio spec requires drivers to set DRIVER_OK before using VQs.
This is set automatically after probe returns, virtio net violated this
rule by using receive VQs within probe.
To fix, call virtio_device_ready before using VQs.
virtio spec 0.9.X requires DRIVER_OK to be set before
VQs are used, but some drivers use VQs before probe
function returns.
Since DRIVER_OK is set after probe, this violates the spec.
Even though under virtio 1.0 transitional devices support this
behaviour, we want to make it possible for those early callers to become
spec compliant and eventually support non-transitional devices.
config_mutex served two purposes: prevent multiple concurrent config
change handlers, and synchronize access to config_enable flag.
Since commit dbf2576e37da0fcc7aacbfbb9fd5d3de7888a3c1
workqueue: make all workqueues non-reentrant
all workqueues are non-reentrant, and config_enable
is now gone.
Now that virtio core ensures config changes don't arrive during probing,
drop config_enable flag in virtio net.
On removal, flush is now sufficient to guarantee that no change work is
queued.
This help simplify the driver, and will allow setting DRIVER_OK earlier
without losing config change notifications.
config_mutex served two purposes: prevent multiple concurrent config
change handlers, and synchronize access to config_enable flag.
Since commit dbf2576e37da0fcc7aacbfbb9fd5d3de7888a3c1
workqueue: make all workqueues non-reentrant
all workqueues are non-reentrant, and config_enable
is now gone.
Now that virtio core ensures config changes don't
arrive during probing, drop config_enable flag
in virtio blk.
On removal, flush is now sufficient to guarantee that
no change work is queued.
This help simplify the driver, and will allow
setting DRIVER_OK earlier without losing config
change notifications.
Defer config changed notifications that arrive during
probe/scan/freeze/restore.
This will allow drivers to set DRIVER_OK earlier, without worrying about
racing with config change interrupts.
This change will also benefit old hypervisors (before 2009)
that send interrupts without checking DRIVER_OK: previously,
the callback could race with driver-specific initialization.
Replace duplicated code in all transports with a single wrapper in
virtio.c.
The only functional change is in virtio_mmio.c: if a buggy device sends
us an interrupt before driver is set, we previously returned IRQ_NONE,
now we return IRQ_HANDLED.
As this must not happen in practice, this does not look like a big deal.
See also commit 3fff0179e33cd7d0a688dab65700c46ad089e934
virtio-pci: do not oops on config change if driver not loaded.
for the original motivation behind the driver check.
On restore, virtio pci does the following:
+ set features
+ init vqs etc - device can be used at this point!
+ set ACKNOWLEDGE,DRIVER and DRIVER_OK status bits
This is in violation of the virtio spec, which
requires the following order:
- ACKNOWLEDGE
- DRIVER
- init vqs
- DRIVER_OK
This behaviour will break with hypervisors that assume spec compliant
behaviour. It seems like a good idea to have this patch applied to
stable branches to reduce the support butden for the hypervisors.
Prarit Bhargava [Mon, 13 Oct 2014 16:21:39 +0000 (02:51 +1030)]
modules, lock around setting of MODULE_STATE_UNFORMED
A panic was seen in the following sitation.
There are two threads running on the system. The first thread is a system
monitoring thread that is reading /proc/modules. The second thread is
loading and unloading a module (in this example I'm using my simple
dummy-module.ko). Note, in the "real world" this occurred with the qlogic
driver module.
CPU 0 (/proc/modules reader)
CPU 1 (loading/unloading module)
CPU 0 opens /proc/modules, and starts displaying data for each module by
traversing the modules list via fs/seq_file.c:seq_open() and
fs/seq_file.c:seq_read(). For each module in the modules list, seq_read
does
op->start() <-- this is a pointer to m_start()
op->show() <- this is a pointer to m_show()
op->stop() <-- this is a pointer to m_stop()
The m_start(), m_show(), and m_stop() module functions are defined in
kernel/module.c. The m_start() and m_stop() functions acquire and release
the module_mutex respectively.
ie) When reading /proc/modules, the module_mutex is acquired and released
for each module.
m_show() is called with the module_mutex held. It accesses the module
struct data and attempts to write out module data. It is in this code
path that the above BUG_ON() warning is encountered, specifically m_show()
calls
The other thread, CPU 1, in unloading the module calls the syscall
delete_module() defined in kernel/module.c. The module_mutex is acquired
for a short time, and then released. free_module() is called without the
module_mutex. free_module() then sets mod->state = MODULE_STATE_UNFORMED,
also without the module_mutex. Some additional code is called and then the
module_mutex is reacquired to remove the module from the modules list:
/* Now we can delete it from the lists */
mutex_lock(&module_mutex);
stop_machine(__unlink_module, mod, NULL);
mutex_unlock(&module_mutex);
This is the sequence of events that leads to the panic.
CPU 1 is removing dummy_module via delete_module(). It acquires the
module_mutex, and then releases it. CPU 1 has NOT set dummy_module->state to
MODULE_STATE_UNFORMED yet.
CPU 0, which is reading the /proc/modules, acquires the module_mutex and
acquires a pointer to the dummy_module which is still in the modules list.
CPU 0 calls m_show for dummy_module. The check in m_show() for
MODULE_STATE_UNFORMED passed for dummy_module even though it is being
torn down.
Meanwhile CPU 1, which has been continuing to remove dummy_module without
holding the module_mutex, now calls free_module() and sets
dummy_module->state to MODULE_STATE_UNFORMED.
CPU 0 now calls module_flags() with dummy_module and ...
Acquire and release the module_mutex lock around the setting of
MODULE_STATE_UNFORMED in the teardown path, which should resolve the
problem.
Testing: In the unpatched kernel I can panic the system within 1 minute by
doing
while (true) do insmod dummy_module.ko; rmmod dummy_module.ko; done
and
while (true) do cat /proc/modules; done
in separate terminals.
In the patched kernel I was able to run just over one hour without seeing
any issues. I also verified the output of panic via sysrq-c and the output
of /proc/modules looks correct for all three states for the dummy_module.
mnt: Prevent pivot_root from creating a loop in the mount tree
Andy Lutomirski recently demonstrated that when chroot is used to set
the root path below the path for the new ``root'' passed to pivot_root
the pivot_root system call succeeds and leaks mounts.
In examining the code I see that starting with a new root that is
below the current root in the mount tree will result in a loop in the
mount tree after the mounts are detached and then reattached to one
another. Resulting in all kinds of ugliness including a leak of that
mounts involved in the leak of the mount loop.
Prevent this problem by ensuring that the new mount is reachable from
the current root of the mount tree.
Eric Dumazet [Mon, 13 Oct 2014 13:27:47 +0000 (06:27 -0700)]
tcp: TCP Small Queues and strange attractors
TCP Small queues tries to keep number of packets in qdisc
as small as possible, and depends on a tasklet to feed following
packets at TX completion time.
Choice of tasklet was driven by latencies requirements.
Then, TCP stack tries to avoid reorders, by locking flows with
outstanding packets in qdisc in a given TX queue.
What can happen is that many flows get attracted by a low performing
TX queue, and cpu servicing TX completion has to feed packets for all of
them, making this cpu 100% busy in softirq mode.
This became particularly visible with latest skb->xmit_more support
Strategy adopted in this patch is to detect when tcp_wfree() is called
from ksoftirqd and let the outstanding queue for this flow being drained
before feeding additional packets, so that skb->ooo_okay can be set
to allow select_queue() to select the optimal queue :
Incoming ACKS are normally handled by different cpus, so this patch
gives more chance for these cpus to take over the burden of feeding
qdisc with future packets.
David S. Miller [Tue, 14 Oct 2014 21:05:23 +0000 (17:05 -0400)]
Merge branch 'qlcnic'
Rajesh Borundia says:
====================
qlcnic: Bug fixes
This series fixes following issues.
* We were programming maximum number of arguments supported by
adapter instead of required in a command.
* Destroy tx command requires three arguments instead of two.
Please apply these patches to net.
====================
Rajesh Borundia [Tue, 14 Oct 2014 11:41:45 +0000 (07:41 -0400)]
qlcnic: Fix programming number of arguments in a command.
o Initially we were programming maximum number of arguments.
Instead we should program number of arguments required in
a command.
o Maximum number of arguments for 82xx adapter is four. Fix it
for GET_ESWITCH_STATS command.
David S. Miller [Tue, 14 Oct 2014 21:02:37 +0000 (17:02 -0400)]
net: Trap attempts to call sock_kfree_s() with a NULL pointer.
Unlike normal kfree() it is never right to call sock_kfree_s() with
a NULL pointer, because sock_kfree_s() also has the side effect of
discharging the memory from the sockets quota.
Use t4_fw_upgrade instead of t4_load_fw to write firmware into FLASH, since
t4_load_fw doesn't co-ordinate with the firmware and the adapter can get hosed
enough to require a power cycle of the system.
When synthesizing maps from files that have incomplete symbol
information, like kallsyms, we need to fixup the end of maps by seting
its end from the ->start of the next map, fix it to set prev_map->end to
curr_map->start, since ->end is the first byte outside prev_map address
range.
A segfault happens on 'perf test hists_link' because we end up using a
struct machines on the stack, and then machines__init() was not
initializing the newly introduced rb_root, just the existing list_head.
When we introduced struct dsos, to group the two ways to store dsos,
i.e. the linked list and the rbtree, we didn't turned the initialization
done in:
David S. Miller [Tue, 14 Oct 2014 20:40:49 +0000 (16:40 -0400)]
Merge branch 'stmmac'
Giuseppe Cavallaro says:
====================
stmmac: review and fix the dwmac-sti glue-logic
This patch is to review the whole glue logic adopted on STi SoCs that
was bugged.
In the old glue-logic there was a lot of confusion when setup the
retiming especially for STiD127 where, for example, the bits 6 and 7
(in the GMAC control register) have a different meaning of what is
used for STiH4xx SoCs. So we cannot adopt the same glue for all these
SoCs.
Moreover, GiGa on STiD127 didn't work and, for all the SoCs, the RGMII
couldn't run when the speed was 10Mbps (because the clock was not properly
managed).
Note that the phy clock needs to be provided by the platform as well as
documented in the related binding file (updated as consequence).
The old code supported too many configurations never adopted and validated.
This made the code very complex to maintain and debug in case of issues.
The patch simplifies all the configurations as commented in the tables
inside the file and obviously it has been tested on all the boards
based on the SoCs mentioned.
With this patch, the dwmac-sti is also ready to support new configurations that
will be available on next SoC generations.
====================
stmmac: dwmac-sti: review the glue-logic for STi4xx and STiD127 SoCs
This patch is to review the whole glue logic adopted on STi SoCs that
was bugged.
In the old glue-logic there was a lot of confusion when setup the
retiming especially for STiD127 where, for example, the bits 6 and 7
(in the GMAC control register) have a different meaning of what is
used for STiH4xx SoCs. So we cannot adopt the same glue for all these
SoCs.
Moreover, GiGa on STiD127 didn't work and, for all the SoCs, the RGMII
couldn't run when the speed was 10Mbps (because the clock was not properly
managed).
Note that the phy clock needs to be provided by the platform as well as
documented in the related binding file (updated as consequence).
The old code supported too many configurations never adopted and validated.
This made the code very complex to maintain and debug in case of issues.
The patch simplifies all the configurations as commented in the tables
inside the file and obviously it has been tested on all the boards
based on the SoCs mentioned.
With this patch, the dwmac-sti is also ready to support new configurations that
will be available on next SoC generations.
On several STi platforms: e.g. stihxxx-b2120 an Ethernet switch is
embedded and connected to the stmmac via RGMII mode. So this is managed
by using the FIXED_PHY. In that case, the support in the platform needs
to be fixed to allow the stmmac to dialog with the switch via fixed-link
by using phy_bus_name property.
perf evlist: Default to syswide target when no thread/cpu maps set
If all a tool wants is to do system wide event monitoring, there is no
more the need to setup thread_map and cpu_map objects, just call
perf_evlist__open() and it will do create one fd per CPU monitoring all
threads.
perf evlist: Check that there is a thread_map when preparing a workload
The perf_evlist__prepare_workload expects a thread map to be in place
so that it can store the pid of the workload being started, so check it
and tell the developer about it instead of segfaulting.
Now tools that deals want to have an hists per evsel need to call
hists__init() before creating any evsels, which can be as early as when
parsing the command line, so do it before calling parse_options().
The current tools using hists/hist_entries are report, top and annotate,
change them to request per evsel hists.
This is in preparation for making evsels usable by 3rd party tools, that
not necessarily live in perf's source code repository.
perf callchain: Move the callchain_param extern to callchain.h
It was lost in hist.h, move it to where it belongs, callchain.h, as
there are places that gets hist.h by means of evsel.h, and since evsel.h
is being untangled from hist.h...
Provide a method to be called at tool start to config the perf_evsel
instance size, together with optional constructor and destructor.
This will be used so that perf_evsel doesn't always include a struct
hists, tools that works with hists/hist_entries, like report, top and
annotate, will, at start, tell the evsel class the size they need per
instance.
v2: Don't use exit as a name of a member of function parameter, as this
breaks the build on at least fedora14 and rhel6.
David S. Miller [Tue, 14 Oct 2014 20:09:38 +0000 (16:09 -0400)]
Merge branch 'xgene'
Iyappan Subramanian says:
====================
Adding SGMII based 1GbE basic support to APM X-Gene SoC ethernet driver.
v2: Address comments from v1
* Split the patchset into two, the first one being preparatory patch
* Added link_state function pointer to the xgene_mac_ops structure
* Added xgene_indirect_ctl structure for indirect read/write arguments
drivers: net: xgene: Preparing for adding SGMII based 1GbE
- Added link_state function pointer to the xgene__mac_ops structure
- Moved ring manager (pdata->rm) assignment to xgene_enet_setup_ops
- Removed unused variable (pdata->phy_addr) and macro (FULL_DUPLEX)
net: filter: move common defines into bpf_common.h
userspace programs that use eBPF instruction macros need to include two files:
uapi/linux/filter.h and uapi/linux/bpf.h
Move common macro definitions that are shared between classic BPF and eBPF
into uapi/linux/bpf_common.h, so that user app can include only one bpf.h file
Mugunthan V N [Mon, 13 Oct 2014 16:51:07 +0000 (22:21 +0530)]
drivers: net: cpsw: remove child devices while driver detach
remove all the child devices from the system to make sure that re-insert of
cpsw module doesn't fail on child device populated by of_platform_populate().
Mugunthan V N [Mon, 13 Oct 2014 16:51:05 +0000 (22:21 +0530)]
drivers: net: davinci_cpdma: remove kfree on objects allocated with devm_* apis
memories allocated with devm_* apis must not be freed with kfree apis,
so removing the kfree calls
Fixes: e194312854ed ('drivers: net: davinci_cpdma: Convert kzalloc() to devm_kzalloc().') Signed-off-by: Mugunthan V N <[email protected]> Signed-off-by: David S. Miller <[email protected]>
Jiri Pirko [Mon, 13 Oct 2014 14:34:10 +0000 (16:34 +0200)]
ipv4: fix nexthop attlen check in fib_nh_match
fib_nh_match does not match nexthops correctly. Example:
ip route add 172.16.10/24 nexthop via 192.168.122.12 dev eth0 \
nexthop via 192.168.122.13 dev eth0
ip route del 172.16.10/24 nexthop via 192.168.122.14 dev eth0 \
nexthop via 192.168.122.15 dev eth0
Del command is successful and route is removed. After this patch
applied, the route is correctly matched and result is:
RTNETLINK answers: No such process
Please consider this for stable trees as well.
Fixes: 4e902c57417c4 ("[IPv4]: FIB configuration using struct fib_config") Signed-off-by: Jiri Pirko <[email protected]> Acked-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]>
Ilya Dryomov [Fri, 10 Oct 2014 12:39:05 +0000 (16:39 +0400)]
libceph: ceph-msgr workqueue needs a resque worker
Commit f363e45fd118 ("net/ceph: make ceph_msgr_wq non-reentrant")
effectively removed WQ_MEM_RECLAIM flag from ceph_msgr_wq. This is
wrong - libceph is very much a memory reclaim path, so restore it.
Fix some coccinelle warnings:
fs/ceph/caps.c:2400:6-10: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2401:6-15: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2402:6-17: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2403:6-22: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2404:6-22: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2405:6-19: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2440:4-20: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2469:3-16: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2490:2-18: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2519:3-7: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2549:3-12: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2575:2-6: WARNING: Assignment of bool to 0/1
fs/ceph/caps.c:2589:3-7: WARNING: Assignment of bool to 0/1
ceph: include the initial ACL in create/mkdir/mknod MDS requests
Current code set new file/directory's initial ACL in a non-atomic
manner.
Client first sends request to MDS to create new file/directory, then set
the initial ACL after the new file/directory is successfully created.
The fix is include the initial ACL in create/mkdir/mknod MDS requests.
So MDS can handle creating file/directory and setting the initial ACL in
one request.
Current code uses page array to present MDS request data. Pages in the
array are allocated/freed by caller of ceph_mdsc_do_request(). If request
is interrupted, the pages can be freed while they are still being used by
the request message.
The fix is use pagelist to present MDS request data. Pagelist is
reference counted.
John Spray [Tue, 9 Sep 2014 18:26:01 +0000 (19:26 +0100)]
ceph: send client metadata to MDS
Implement version 2 of CEPH_MSG_CLIENT_SESSION syntax,
which includes additional client metadata to allow
the MDS to report on clients by user-sensible names
like hostname.
David S. Miller [Tue, 14 Oct 2014 19:05:39 +0000 (15:05 -0400)]
Merge branch 'isdn'
Tilman Schmidt says:
====================
Coverity patches for drivers/isdn
Here's a series of patches for the ISDN CAPI subsystem and the
Gigaset ISDN driver.
Patches 1 to 7 are specific fixes for Coverity warnings.
Patches 8 to 11 fix related problems with the handling of invalid
CAPI command codes I noticed while working on this.
Patch 12 fixes an unrelated problem I noticed during the subsequent
regression tests.
It would be great if these could still be merged.
====================
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/gigaset: fix usb_gigaset write_cmd result race
In usb_gigaset function gigaset_write_cmd(), the length field of
the command buffer structure could be cleared by the transmit
tasklet before it was used for the function's return value.
Fix by copying to a local variable before scheduling the tasklet.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/capi: don't return NULL from capi_cmd2str()
capi_cmd2str() is used in many places to build log messages.
None of them is prepared to handle NULL as a result.
Change the function to return printable string "INVALID_COMMAND"
instead.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/capi: prevent NULL pointer dereference on invalid CAPI command
An invalid CAPI 2.0 command/subcommand combination may retrieve a
NULL pointer from the cpars[] array which will later be dereferenced
by the parser routines.
Fix by adding NULL pointer checks in strategic places.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/capi: prevent index overrun from command_2_index()
The result of the function command_2_index() is used to index two
arrays mnames[] and cpars[] with max. index 0x4e but in its current
form that function can produce results up to 3*(0x9+0x9)+0x7f =
0xb5.
Fix by clamping all result values potentially overrunning the arrays
to zero which is already handled as an invalid value.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/capi: correct capi20_manufacturer argument type mismatch
Function capi20_manufacturer() is declared with unsigned int cmd
argument but called with unsigned long.
Fix by correcting the function prototype since the actual argument
is part of the user visible API.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:30 +0000 (13:46 +0200)]
isdn/gigaset: fix non-heap pointer deallocation
at_state structures may be allocated individually or as part of a
cardstate or bc_state structure. The disconnect() function handled
both cases, creating a risk that it might try to deallocate an
at_state structure that had not been allocated individually.
Fix by splitting disconnect() into two variants handling cases
with and without an associated B channel separately, and adding
an explicit check.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:29 +0000 (13:46 +0200)]
isdn/gigaset: limit raw CAPI message dump length
In dump_rawmsg, the length field from a received data package was
used unscrutinized, allowing an attacker to control the size of the
allocated buffer and the number of times the output loop iterates.
Fix by limiting to a reasonable value.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:29 +0000 (13:46 +0200)]
isdn/gigaset: make sure controller name is null terminated
In gigaset_isdn_regdev, the name field may not have a null terminator
if the source string's length is equal to the buffer size.
Fix by zero filling the structure and excluding the last byte of the
name field from the copy.
Tilman Schmidt [Sat, 11 Oct 2014 11:46:29 +0000 (13:46 +0200)]
isdn/gigaset: missing break in do_facility_req
If we take the unsupported supplementary service notification mask
path, we end up falling through and overwriting the error code.
Insert a break statement to skip the remainder of the switch case
and proceed to sending the reply message.
David S. Miller [Tue, 14 Oct 2014 18:45:17 +0000 (14:45 -0400)]
Merge branch 'fec-ptp'
Luwei Zhou says:
====================
Enable FEC pps feather
Change from v2 to v3:
-Using the default channel 0 to be PPS channel not PTP_PIN_SET/GETFUNC interface.
-Using the linux definition of NSEC_PER_SEC.
Change from v1 to v2:
- Fix the potential 32-bit multiplication overflow issue.
- Optimize the hareware adjustment code to improve efficiency as Richard suggested
- Use ptp PTP_PIN_SET/GETFUNC interface to set PPS channel not device tree
and add PTP_PF_PPS enumeration
- Modify comments style
====================
Luwei Zhou [Fri, 10 Oct 2014 05:15:30 +0000 (13:15 +0800)]
net: fec: ptp: Enable PPS output based on ptp clock
FEC ptp timer has 4 channel compare/trigger function. It can be used to
enable pps output.
The pulse would be ouput high exactly on N second. The pulse ouput high
on compare event mode is used to produce pulse per second. The pulse
width would be one cycle based on ptp timer clock source.Since 31-bit
ptp hardware timer is used, the timer will wrap more than 2 seconds. We
need to reload the compare compare event about every 1 second.
Luwei Zhou [Fri, 10 Oct 2014 05:15:29 +0000 (13:15 +0800)]
net: fec: ptp: Use hardware algorithm to adjust PTP counter.
The FEC IP supports hardware adjustment for ptp timer. Refer to the description of
ENET_ATCOR and ENET_ATINC registers in the spec about the hardware adjustment. This
patch uses hardware support to adjust the ptp offset and frequency on the slave side.
Luwei Zhou [Fri, 10 Oct 2014 05:15:28 +0000 (13:15 +0800)]
net: fec: ptp: Use the 31-bit ptp timer.
When ptp switches from software adjustment to hardware ajustment, linux ptp can't converge.
It is caused by the IP limit. Hardware adjustment logcial have issue when ptp counter
runs over 0x80000000(31 bit counter). The internal IP reference manual already remove 32bit
free-running count support. This patch replace the 32-bit PTP timer with 31-bit.
1.
JIT compiler using multi-pass approach to converge to final image size,
since x86 instructions are variable length. It starts with large
gaps between instructions (so some jumps may use imm32 instead of imm8)
and iterates until total program size is the same as in previous pass.
This algorithm works only if program size is strictly decreasing.
Programs that use LD_ABS insn need additional code in prologue, but it
was not emitted during 1st pass, so there was a chance that 2nd pass would
adjust imm32->imm8 jump offsets to the same number of bytes as increase in
prologue, which may cause algorithm to erroneously decide that size converged.
Fix it by always emitting largest prologue in the first pass which
is detected by oldproglen==0 check.
Also change error check condition 'proglen != oldproglen' to fail gracefully.
2.
while staring at the code realized that 64-byte buffer may not be enough
when 1st insn is large, so increase it to 128 to avoid buffer overflow
(theoretical maximum size of prologue+div is 109) and add runtime check.