Eric W. Biederman says:
====================
Introduce possible_net_t
The current usage of write_pnet and read_pnet is a little laborious and
error prone as you only notice if you failed to include them if are
compiling with network namespaces enabled.
possible_net_t remedies that by using a type that is 0 bytes when
network namespaces are disabled and can only be read and written to with
read_pnet and write_pnet.
Aka less work and safer for the same effect.
I kill hold_net and release_net first as are they are haven't been used
since 2008 and are noise at the points where write_pnet and read_pnet
are used.
I have folded in Eric Dumazets suggestions to improve the killing of
hold_net and release net. And respon. I had to respin anyway as
there was enough changes elsewhere in the tree the previous version
of these patches did not quite apply cleanly.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Having to say
> #ifdef CONFIG_NET_NS
> struct net *net;
> #endif
in structures is a little bit wordy and a little bit error prone.
Instead it is possible to say:
> typedef struct {
> #ifdef CONFIG_NET_NS
> struct net *net;
> #endif
> } possible_net_t;
And then in a header say:
> possible_net_t net;
Which is cleaner and easier to use and easier to test, as the
possible_net_t is always there no matter what the compile options.
Further this allows read_pnet and write_pnet to be functions in all
cases which is better at catching typos.
This change adds possible_net_t, updates the definitions of read_pnet
and write_pnet, updates optional struct net * variables that
write_pnet uses on to have the type possible_net_t, and finally fixes
up the b0rked users of read_pnet and write_pnet.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hold_net and release_net were an idea that turned out to be useless.
The code has been disabled since 2008. Kill the code it is long past due.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Herbert Xu says:
====================
rhashtable hash cleanups
This is a rebase on top of the nested lock annotation fix.
Nothing to see here, just a bunch of simple clean-ups before
I move onto something more substantial (hopefully).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that the only caller of obj_raw_hashfn is head_hashfn, we can
simply kill it and fold it into the latter.
This patch also moves the common shift from head_hashfn/key_hashfn
into rht_bucket_index.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
key_hashfn has only one caller and it doesn't really need to supply
the key length as an extra parameter.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that we don't have cross-table hashes, we no longer need to
keep the entire hash value so all users of obj_raw_hashfn can
use head_hashfn instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch reverts commit c88455ce50
("rhashtable: key_hashfn() must return full hash value") because
the only user of it always masks the hash value.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
type T;
identifier f;
@@
static T f (...) { ... }
@@
identifier r.f;
declarer name EXPORT_SYMBOL;
@@
-EXPORT_SYMBOL(f);
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit aa34a6cb04 ("rhashtable:
Add arbitrary rehash function") killed the annotation on the
nested lock which leads to bitching from lockdep.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
I forgot to use write_pnet() in three locations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 33cf7c90fe ("net: add real socket cookies")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes it possible to retain the route preference when RAs are handled in
userspace.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Flags are used in the return path rather than the return patch.
Fixes: af33c1adae ("vxlan: Eliminate dependency on UDP socket in transmit path")
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A long standing problem in netlink socket dumps is the use
of kernel socket addresses as cookies.
1) It is a security concern.
2) Sockets can be reused quite quickly, so there is
no guarantee a cookie is used once and identify
a flow.
3) request sock, establish sock, and timewait socks
for a given flow have different cookies.
Part of our effort to bring better TCP statistics requires
to switch to a different allocator.
In this patch, I chose to use a per network namespace 64bit generator,
and to use it only in the case a socket needs to be dumped to netlink.
(This might be refined later if needed)
Note that I tried to carry cookies from request sock, to establish sock,
then timewait sockets.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eric Salo <salo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we merged the tries for local and main I had overlooked the iterator
for /proc/net/route. As a result it was outputting both local and main
when the two tries were merged.
This patch resolves that by only providing output for aliases that are
actually in the main trie. As a result we should go back to the original
behavior which I assume will be necessary to maintain legacy support.
Fixes: 0ddcf43d5 ("ipv4: FIB Local/MAIN table collapse")
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: dsa: support PHY reads/writes diversion
This patch series completes the PHY reads/writes diversion when we need to use
the slave MII bus provided by DSA and the underlying switch drivers to
implement the real PHY reads and writes. This is particularly useful when they
are conflicting MDIO bus addresses as in the case of multiple Broadcom switches
connected to each other (internal and external, or just external).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In case a PHY is found via Device Tree, and is also flagged by the
switch driver as needing indirect reads/writes using the switch driver
implemented MDIO bus, make sure that we bind this PHY to the slave MII
bus in order for this to happen.
Without this, we would succeed in having the PHY driver probe()'s
function to use slave MII bus read/write functions, because this is done
during dsa_slave_mii_init(), but past that point, the PHY driver would
not go through these diverted reads and writes.
Fixes: 0d8bcdd383 ("net: dsa: allow for more complex PHY setups")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for dealing with indirect reads and writes towards
certain PHY devices, move the code which deals with binding the PHY
device to the slave MII bus created by DSA to its own function:
dsa_slave_phy_connect().
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Export of_mdio_parse_addr() which allows parsing a given Ethernet PHY
node MDIO address, verify it is within the allowed range, and return
its value. This is going to be useful for the DSA code which needs to
deal with multiple layers of MDIO buses.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Bits 31:16 of RDMA_PROD_INDEX contain Rx discarded packet count, which
are the Rx packets that had to be dropped by MAC hardware since there
was no room on the Rx queue. Add code to collect this information into
the netdev stats.
Signed-off-by: Petri Gynther <pgynther@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 0-day kernel test infrastructure reported a use of uninitialized
variable warning for local_table due to the fact that the local and main
allocations had been swapped from the original setup. This change corrects
that by making it so that we free the main table if the local table
allocation fails.
Fixes: 0ddcf43d5 ("ipv4: FIB Local/MAIN table collapse")
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move rtnl_lock() before the call to fib4_rules_exit so that
fib_table_flush_external is called under RTNL.
Fixes: 104616e74e ("switchdev: don't support custom ip rules, for now")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
CONFIG_MPLS=m doesn't result in a kernel module being built because it
applies to the net/mpls directory, rather than to .o files.
So revert the MPLS menuitem to being a boolean and make MPLS_GSO and
MPLS_ROUTING tristates to allow mpls_gso and mpls_router modules to be
produced as desired.
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
FSL_PQ_MDIO and FSL_XGMAC_MDIO are not really depend on FSL_SOC, they
can build on non-PPC platforms.
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a rehash function that supports the use of any
hash function for the new table. This is needed to support changing
the random seed value during the lifetime of the hash table.
However for now the random seed value is still constant and the
rehash function is simply used to replace the existing expand/shrink
functions.
[ ASSERT_BUCKET_LOCK() and thus debug_dump_table() +
debug_dump_buckets() are not longer used, so delete them
entirely. -DaveM ]
Signed-off-by: Herbert Xu <herbert.xu@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently hash_rnd is a parameter that users can set. However,
no existing users set this parameter. It is also something that
people are unlikely to want to set directly since it's just a
random number.
In preparation for allowing the reseeding/rehashing of rhashtable,
this patch moves hash_rnd into bucket_table so that it's now an
internal state rather than a parameter.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is meant to collapse local and main into one by converting
tb_data from an array to a pointer. Doing this allows us to point the
local table into the main while maintaining the same variables in the
table.
As such the tb_data was converted from an array to a pointer, and a new
array called data is added in order to still provide an object for tb_data
to point to.
In order to track the origin of the fib aliases a tb_id value was added in
a hole that existed on 64b systems. Using this we can also reverse the
merge in the event that custom FIB rules are enabled.
With this patch I am seeing an improvement of 20ns to 30ns for routing
lookups as long as custom rules are not enabled, with custom rules enabled
we fall back to split tables and the original behavior.
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit afaa3f65f6
(tipc: purge links when bearer is disabled) was an attempt to resolve
a problem that turned out to have a more profound reason.
When we disable a bearer, we delete all its pertaining links if
there is no other bearer to perform failover to, or if the module
is shutting down. In case there are dual bearers, we wait with
deleting links until the failover procedure is finished.
However, this misses the case when a link on the removed bearer
was already down, so that there will be no failover procedure to
finish the link delete. This causes confusion if a new bearer is
added to replace the removed one, and also entails a small memory
leak.
This commit takes the current state of the link into account when
deciding when to delete it, and also reverses the above-mentioned
commit.
Reviewed-by: Erik Hugne <erik.hugne@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the inflate call failed it would return NULL. As a result tp would be
set to NULL and cause use to trigger a NULL pointer dereference in
should_halve if the inflate failed on the first attempt.
In order to prevent this we should decrement max_work before we actually
attempt to inflate as this will force us to exit before attempting to halve
a node we should have inflated. In order to keep things symmetric between
inflate and halve I went ahead and also moved the decrement of max_work for
the halve case as well so we take care of that before we actually attempt
to halve the tnode.
Fixes: 88bae714 ("fib_trie: Add key vector to root, return parent key_vector in resize")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code removed by commit 421d9df062 ("net/macb: merge
at91_ether driver into macb driver") should be removed
in the merge resolution as well.
Signed-off-by: David S. Miller <davem@davemloft.net>
In the case of a trie that had no tnodes with a key of 0 the initial
look-up would fail resulting in an out-of-bounds cindex on the first tnode.
This resulted in an entire trie being skipped.
In order resolve this I have updated the cindex logic in the initial
look-up so that if the key is zero we will always traverse the child zero
path.
Fixes: 8be33e95 ("fib_trie: Fib walk rcu should take a tnode and key instead of a trie and a leaf")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet says:
====================
inet_diag: cleanups and improvements
Before changing way request socks are dumped, let's clean up this code
a bit.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove all inline keywords, add some const, and cleanup style.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sock_diag_check_cookie() second parameter is constant
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net-next
The following batch contains a couple of fixes to address some fallout
from the previous pull request, they are:
1) Address link problems in the bridge code after e5de75b. Fix it by
using rcu hook to address to avoid ifdef pollution and hard
dependency between bridge and br_netfilter.
2) Address sparse warnings in the netfilter reject code, patch from
Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
e5de75b ("netfilter: bridge: move DNAT helper to br_netfilter") results
in the following link problem:
net/bridge/br_device.c:29: undefined reference to `br_nf_prerouting_finish_bridge`
Moreover it creates a hard dependency between br_netfilter and the
bridge core, which is what we've been trying to avoid so far.
Resolve this problem by using a hook structure so we reduce #ifdef
pollution and keep bridge netfilter specific code under br_netfilter.c
which was the original intention.
Reported-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
make C=1 CF=-D__CHECK_ENDIAN__ shows following:
net/bridge/netfilter/nft_reject_bridge.c:65:50: warning: incorrect type in argument 3 (different base types)
net/bridge/netfilter/nft_reject_bridge.c:65:50: expected restricted __be16 [usertype] protocol [..]
net/bridge/netfilter/nft_reject_bridge.c:102:37: warning: cast from restricted __be16
net/bridge/netfilter/nft_reject_bridge.c:102:37: warning: incorrect type in argument 1 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:121:50: warning: incorrect type in argument 3 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:168:52: warning: incorrect type in argument 3 (different base types) [..]
net/bridge/netfilter/nft_reject_bridge.c:233:52: warning: incorrect type in argument 3 (different base types) [..]
Caused by two (harmless) errors:
1. htons() instead of ntohs()
2. __be16 for protocol in nf_reject_ipXhdr_put API, use u8 instead.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
BCM7439 has an alternate PHY OUI: 0xae025080 which is to be found in
some variants of this chip.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass in the netlink flags (NLM_F_*) into switchdev driver for IPv4 FIB add op
to allow driver to 1) optimize hardware updates, 2) handle ip route prepend
and append commands correctly.
Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Suggested-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: dsa: remove restriction on platform_device
This patch series removes the restriction in DSA to operate exclusively with
platform_device Ethernet MAC drivers when using Device Tree. This basically
allows arbitrary Ethernet MAC drivers to be used now in conjunction with
Device Tree.
The reason was that DSA was using a of_find_device_by_node() which limits
the device_node to device pointer search exclusively to platform_device,
in our case, we are interested in doing a "class" research and lookup the
net_device.
Thanks to Chris Packham for testing this on his platform.
Changes in v2:
- fix build for !CONFIG_OF_NET
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Using of_find_device_by_node() restricts the search to platform_device that
match the specified device_node pointer. This is not even remotely true for
network devices backed by a pci_device for instance.
of_find_net_device_by_node() allows us to do a more thorough lookup to find the
struct net_device corresponding to a particular device_node pointer.
For symetry with the non-OF code path, we hold the net_device pointer in
dsa_probe() just like what dev_to_net_dev() does when we call this
function.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a helper function which allows getting the struct net_device pointer
associated with a given struct device_node pointer. This is useful for
instance for DSA Ethernet devices not backed by a platform_device, but a PCI
device.
Since we need to access net_class which is not accessible outside of
net/core/net-sysfs.c, this helper function is also added here and gated
with CONFIG_OF_NET.
Network devices initialized with SET_NETDEV_DEV() are also taken into
account by checking for dev->parent first and then falling back to
checking the device pointer within struct net_device.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/cadence/macb.c
Overlapping changes in macb driver, mostly fixes and cleanups
in 'net' overlapping with the integration of at91_ether into
macb in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
1. Add struct bcmgenet_rx_ring to hold all necessary information
for a single Rx queue.
2. Add bcmgenet_init_rx_queues() to initialize all Rx queues.
3. Modify bcmgenet_init_rx_ring() to initialize a single Rx queue.
4. Modify Rx interrupt path code to use per-queue data.
5. Modify bcmgenet_rx_refill() to use RxCB->bd_addr.
Signed-off-by: Petri Gynther <pgynther@google.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull kvm/s390 bugfixes from Marcelo Tosatti.
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: s390: non-LPAR case obsolete during facilities mask init
KVM: s390: include guest facilities in kvm facility test
KVM: s390: fix in memory copy of facility lists
KVM: s390/cpacf: Fix kernel bug under z/VM
KVM: s390/cpacf: Enable key wrapping by default
Pull s390 fixes from Martin Schwidefsky:
"One performance optimization for page_clear and a couple of bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/mm: fix incorrect ASCE after crst_table_downgrade
s390/ftrace: fix crashes when switching tracers / add notrace to cpu_relax()
s390/pci: unify pci_iomap symbol exports
s390/pci: fix [un]map_resources sequence
s390: let the compiler do page clearing
s390/pci: fix possible information leak in mmio syscall
s390/dcss: array index 'i' is used before limits check.
s390/scm_block: fix off by one during cluster reservation
s390/jump label: improve and fix sanity check
s390/jump label: add missing jump_label_apply_nops() call
contains fixes to ftrace when /proc/sys/kernel/ftrace_enabled and
function tracing are started. Doing the following causes some issues:
# echo 0 > /proc/sys/kernel/ftrace_enabled
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# echo 1 > /proc/sys/kernel/ftrace_enabled
# echo nop > /sys/kernel/debug/tracing/current_tracer
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
As well as with function tracing too. Pratyush Anand first reported
this issue to me and supplied a patch. When I tested this on my x86
test box, it caused thousands of backtraces and warnings to appear in
dmesg, which also caused a denial of service (a warning for every
function that was listed). I applied Pratyush's patch but it did not
fix the issue for me. I looked into it and found a slight problem
with trampoline accounting. I fixed it and sent Pratyush a patch, but
he said that it did not fix the issue for him.
I later learned tha Pratyush was using an ARM64 server, and when I tested
on my ARM board, I was able to reproduce the same issue as Pratyush.
After applying his patch, it fixed the problem. The above test uncovered
two different bugs, one in x86 and one in ARM and ARM64. As this looked
like it would affect PowerPC, I tested it on my PPC64 box. It too broke,
but neither the patch that fixed ARM or x86 fixed this box (the changes
were all in generic code!). The above test, uncovered two more bugs that
affected PowerPC. Again, the changes were only done to generic code.
It's the way the arch code expected things to be done that was different
between the archs. Some where more sensitive than others.
The rest of this series fixes the PPC bugs as well.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJU/cQSAAoJEEjnJuOKh9lde9sH/1MAPq+6jr7YaEFru0GKajE9
rVHjw8rde/I4tN2UxIVk+Qm6pXRZYpv3OKxHT48EHzkvgm++voioykpJP4IEVrP5
mEDuIcYe28csE2nV5u5Q9kwnZoC86TQW5nVV6zB1Gx/3IEzA8Z046jAov40Jya0y
zqHc/U43JeeVIDIOkwjzbH6OaFEDP13FkF3TO502WJhJLqMo+kPOalIgv0eauKzy
lVCQBSC4WS3rVsgW4W3dSrEBaUxbJxgunjxOuV2DwHj5eghHq0M2MKeIUxBz0PuN
wnhTrpf5cAfshTvYHxKlE0uItdyYfVb7UChAD5zTbBL4kMUFhpb183zVKH8K8kU=
=8R8y
-----END PGP SIGNATURE-----
Merge tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull seq-buf/ftrace fixes from Steven Rostedt:
"This includes fixes for seq_buf_bprintf() truncation issue. It also
contains fixes to ftrace when /proc/sys/kernel/ftrace_enabled and
function tracing are started. Doing the following causes some issues:
# echo 0 > /proc/sys/kernel/ftrace_enabled
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
# echo 1 > /proc/sys/kernel/ftrace_enabled
# echo nop > /sys/kernel/debug/tracing/current_tracer
# echo function_graph > /sys/kernel/debug/tracing/current_tracer
As well as with function tracing too. Pratyush Anand first reported
this issue to me and supplied a patch. When I tested this on my x86
test box, it caused thousands of backtraces and warnings to appear in
dmesg, which also caused a denial of service (a warning for every
function that was listed). I applied Pratyush's patch but it did not
fix the issue for me. I looked into it and found a slight problem
with trampoline accounting. I fixed it and sent Pratyush a patch, but
he said that it did not fix the issue for him.
I later learned tha Pratyush was using an ARM64 server, and when I
tested on my ARM board, I was able to reproduce the same issue as
Pratyush. After applying his patch, it fixed the problem. The above
test uncovered two different bugs, one in x86 and one in ARM and
ARM64. As this looked like it would affect PowerPC, I tested it on my
PPC64 box. It too broke, but neither the patch that fixed ARM or x86
fixed this box (the changes were all in generic code!). The above
test, uncovered two more bugs that affected PowerPC. Again, the
changes were only done to generic code. It's the way the arch code
expected things to be done that was different between the archs. Some
where more sensitive than others.
The rest of this series fixes the PPC bugs as well"
* tag 'trace-fixes-v4.0-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix ftrace enable ordering of sysctl ftrace_enabled
ftrace: Fix en(dis)able graph caller when en(dis)abling record via sysctl
ftrace: Clear REGS_EN and TRAMP_EN flags on disabling record via sysctl
seq_buf: Fix seq_buf_bprintf() truncation
seq_buf: Fix seq_buf_vprintf() truncation
David S. Miller
Eric W. Biederman
Herbert Xu
Julia Lawall
Eric Dumazet
Lubomir Rintel
Simon Horman
Alexander Duyck
Florian Fainelli
Petri Gynther
Sabrina Dubroca
Robert Shearman
Shaohui Xie
Jon Paul Maloy
Stephen Rothwell
Florian Westphal
Pablo Neira Ayuso
Scott Feldman
Linus Torvalds