ring_buffer_poll_wait() should always put the poll_table to its wait_queue
even there is immediate data available. Otherwise, the following epoll and
read sequence will eventually hang forever:
1. Put some data to make the trace_pipe ring_buffer read ready first
2. epoll_ctl(efd, EPOLL_CTL_ADD, trace_pipe_fd, ee)
3. epoll_wait()
4. read(trace_pipe_fd) till EAGAIN
5. Add some more data to the trace_pipe ring_buffer
6. epoll_wait() -> this epoll_wait() will block forever
~ During the epoll_ctl(efd, EPOLL_CTL_ADD,...) call in step 2,
ring_buffer_poll_wait() returns immediately without adding poll_table,
which has poll_table->_qproc pointing to ep_poll_callback(), to its
wait_queue.
~ During the epoll_wait() call in step 3 and step 6,
ring_buffer_poll_wait() cannot add ep_poll_callback() to its wait_queue
because the poll_table->_qproc is NULL and it is how epoll works.
~ When there is new data available in step 6, ring_buffer does not know
it has to call ep_poll_callback() because it is not in its wait queue.
Hence, block forever.
Other poll implementation seems to call poll_wait() unconditionally as the very
first thing to do. For example, tcp_poll() in tcp.c.
Link: http://lkml.kernel.org/p/20140610060637.GA14045@devbig242.prn2.facebook.com
Cc: stable@vger.kernel.org # 2.6.27
Fixes: 2a2cc8f7c4 "ftrace: allow the event pipe to be polled"
Reviewed-by: Chris Mason <clm@fb.com>
Signed-off-by: Martin Lau <kafai@fb.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Commit 1ab6c4997e (fs: convert fs shrinkers to new scan/count API)
accidentally removed locking from quota shrinker. Fix it -
dqcache_shrink_scan() should use dq_list_lock to protect the
scan on free_dquots list.
CC: stable@vger.kernel.org
Fixes: 1ab6c4997e
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The block size for the dm-cache's data device must remained fixed for
the life of the cache. Disallow any attempt to change the cache's data
block size.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
The block size for the thin-pool's data device must remained fixed for
the life of the thin-pool. Disallow any attempt to change the
thin-pool's data block size.
It should be noted that attempting to change the data block size via
thin-pool table reload will be ignored as a side-effect of the thin-pool
handover that the thin-pool target does during thin-pool table reload.
Here is an example outcome of attempting to load a thin-pool table that
reduced the thin-pool's data block size from 1024K to 512K.
Before:
kernel: device-mapper: thin: 253:4: growing the data device from 204800 to 409600 blocks
After:
kernel: device-mapper: thin metadata: changing the data block size (from 2048 to 1024) is not supported
kernel: device-mapper: table: 253:4: thin-pool: Error creating metadata object
kernel: device-mapper: ioctl: error adding target to table
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
The TRACE_ITER_PRINTK check in __trace_puts/__trace_bputs is missing,
so add it, to be consistent with __trace_printk/__trace_bprintk.
Those functions are all called by the same function: trace_printk().
Link: http://lkml.kernel.org/p/51E7A7D6.8090900@huawei.com
Cc: stable@vger.kernel.org # 3.11+
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull fuse fixes from Miklos Szeredi:
"This contains miscellaneous fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: replace count*size kzalloc by kcalloc
fuse: release temporary page if fuse_writepage_locked() failed
fuse: restructure ->rename2()
fuse: avoid scheduling while atomic
fuse: handle large user and group ID
fuse: inode: drop cast
fuse: ignore entry-timeout on LOOKUP_REVAL
fuse: timeout comparison fix
Pull networking fixes from David Miller:
1) Bluetooth pairing fixes from Johan Hedberg.
2) ieee80211_send_auth() doesn't allocate enough tail room for the SKB,
from Max Stepanov.
3) New iwlwifi chip IDs, from Oren Givon.
4) bnx2x driver reads wrong PCI config space MSI register, from Yijing
Wang.
5) IPV6 MLD Query validation isn't strong enough, from Hangbin Liu.
6) Fix double SKB free in openvswitch, from Andy Zhou.
7) Fix sk_dst_set() being racey with UDP sockets, leading to strange
crashes, from Eric Dumazet.
8) Interpret the NAPI budget correctly in the new systemport driver,
from Florian Fainelli.
9) VLAN code frees percpu stats in the wrong place, leading to crashes
in the get stats handler. From Eric Dumazet.
10) TCP sockets doing a repair can crash with a divide by zero, because
we invoke tcp_push() with an MSS value of zero. Just skip that part
of the sendmsg paths in repair mode. From Christoph Paasch.
11) IRQ affinity bug fixes in mlx4 driver from Amir Vadai.
12) Don't ignore path MTU icmp messages with a zero mtu, machines out
there still spit them out, and all of our per-protocol handlers for
PMTU can cope with it just fine. From Edward Allcutt.
13) Some NETDEV_CHANGE notifier invocations were not passing in the
correct kind of cookie as the argument, from Loic Prylli.
14) Fix crashes in long multicast/broadcast reassembly, from Jon Paul
Maloy.
15) ip_tunnel_lookup() doesn't interpret wildcard keys correctly, fix
from Dmitry Popov.
16) Fix skb->sk assigned without taking a reference to 'sk' in
appletalk, from Andrey Utkin.
17) Fix some info leaks in ULP event signalling to userspace in SCTP,
from Daniel Borkmann.
18) Fix deadlocks in HSO driver, from Olivier Sobrie.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (93 commits)
hso: fix deadlock when receiving bursts of data
hso: remove unused workqueue
net: ppp: don't call sk_chk_filter twice
mlx4: mark napi id for gro_skb
bonding: fix ad_select module param check
net: pppoe: use correct channel MTU when using Multilink PPP
neigh: sysctl - simplify address calculation of gc_* variables
net: sctp: fix information leaks in ulpevent layer
MAINTAINERS: update r8169 maintainer
net: bcmgenet: fix RGMII_MODE_EN bit
tipc: clear 'next'-pointer of message fragments before reassembly
r8152: fix r8152_csum_workaround function
be2net: set EQ DB clear-intr bit in be_open()
GRE: enable offloads for GRE
farsync: fix invalid memory accesses in fst_add_one() and fst_init_card()
igb: do a reset on SR-IOV re-init if device is down
igb: Workaround for i210 Errata 25: Slow System Clock
usbnet: smsc95xx: add reset_resume function with reset operation
dp83640: Always decode received status frames
r8169: disable L23
...
Running my ftrace tests on PowerPC, it failed the test that checks
if function_graph tracer is affected by the stack tracer. It was.
Looking into this, I found that the update_function_graph_func()
must be called even if the trampoline function is not changed.
This is because archs like PowerPC do not support ftrace_ops being
passed by assembly and instead uses a helper function (what the
trampoline function points to). Since this function is not changed
even when multiple ftrace_ops are added to the code, the test that
falls out before calling update_function_graph_func() will miss that
the update must still be done.
Call update_function_graph_function() for all calls to
update_ftrace_function()
Cc: stable@vger.kernel.org # 3.3+
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Currently trace option stacktrace is not applicable for
trace_printk with constant string argument, the reason is
in __trace_puts/__trace_bputs ftrace_trace_stack is missing.
In contrast, when using trace_printk with non constant string
argument(will call into __trace_printk/__trace_bprintk), then
trace option stacktrace is workable, this inconstant result
will confuses users a lot.
Link: http://lkml.kernel.org/p/51E7A7C9.9040401@huawei.com
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
When the initialization of Intel HDMI controller fails due to missing
i915 kernel symbols (e.g. HD-audio is built in while i915 is module),
the driver discontinues the probe. However, since the probe was done
asynchronously, the driver object still remains, thus the relevant PM
ops are still called at suspend/resume. This results in the bad access
to the incomplete audio card object, eventually leads to Oops or stall
at PM.
This patch adds the missing checks of chip->init_failed flag at each
PM callback in order to fix the problem above.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79561
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This patch fixes a NULL pointer dereference issue introduced by
commit 1f0b63866f (ACPI / PM: Hold ACPI scan lock over the "freeze"
sleep state).
Fixes: 1f0b63866f (ACPI / PM: Hold ACPI scan lock over the "freeze" sleep state)
Link: http://marc.info/?l=linux-pm&m=140541182017443&w=2
Reported-and-tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The commit [247bc037: PM / Sleep: Mitigate race between the freezer
and request_firmware()] introduced the finer state control, but it
also leads to a new bug; for example, a bug report regarding the
firmware loading of intel BT device at suspend/resume:
https://bugzilla.novell.com/show_bug.cgi?id=873790
The root cause seems to be a small window between the process resume
and the clear of usermodehelper lock. The request_firmware() function
checks the UMH lock and gives up when it's in UMH_DISABLE state. This
is for avoiding the invalid f/w loading during suspend/resume phase.
The problem is, however, that usermodehelper_enable() is called at the
end of thaw_processes(). Thus, a thawed process in between can kick
off the f/w loader code path (in this case, via btusb_setup_intel())
even before the call of usermodehelper_enable(). Then
usermodehelper_read_trylock() returns an error and request_firmware()
spews WARN_ON() in the end.
This oneliner patch fixes the issue just by setting to UMH_FREEZING
state again before restarting tasks, so that the call of
request_firmware() will be blocked until the end of this function
instead of returning an error.
Fixes: 247bc03742 (PM / Sleep: Mitigate race between the freezer and request_firmware())
Link: https://bugzilla.novell.com/show_bug.cgi?id=873790
Cc: 3.4+ <stable@vger.kernel.org> # 3.4+
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
deadlock fix.
* 'linux-3.16' of git://anongit.freedesktop.org/git/nouveau/linux-2.6:
drm/nouveau/therm: fix a potential deadlock in the therm monitoring code
When the module sends bursts of data, sometimes a deadlock happens in
the hso driver when the tty buffer doesn't get the chance to be flushed
quickly enough.
Remove the endless while loop in function put_rxbuf_data() which is
called by the urb completion handler.
If there isn't enough room in the tty buffer, discards all the data
received in the URB.
Cc: David Miller <davem@davemloft.net>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Dan Williams <dcbw@redhat.com>
Cc: Jan Dumon <j.dumon@option.com>
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The workqueue "retry_unthrottle_workqueue" is not scheduled anywhere
in the code. So, remove it.
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
to be built on platforms which don't provide the DMA mapping API.
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Merge tag 'firewire-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull firewire fix from Stefan Richter:
"The 1394 drivers cannot and are not supposed to be built on platforms
which don't provide the DMA mapping API (regression since v3.16-rc1
with CONFIG_COMPILE_TEST=y on some architectures)"
* tag 'firewire-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
firewire: IEEE 1394 (FireWire) support should depend on HAS_DMA
Pull another aio fix from Ben LaHaise:
"put_reqs_available() can now be called from within irq context, which
means that it (and its sibling function get_reqs_available()) now need
to be irq-safe, not just preempt-safe"
* git://git.kvack.org/~bcrl/aio-fixes:
aio: protect reqs_available updates from changes in interrupt handlers
The l2tp [get|set]sockopt() code has fallen back to the UDP functions
for socket option levels != SOL_PPPOL2TP since day one, but that has
never actually worked, since the l2tp socket isn't an inet socket.
As David Miller points out:
"If we wanted this to work, it'd have to look up the tunnel and then
use tunnel->sk, but I wonder how useful that would be"
Since this can never have worked so nobody could possibly have depended
on that functionality, just remove the broken code and return -EINVAL.
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: James Chapman <jchapman@katalix.com>
Acked-by: David Miller <davem@davemloft.net>
Cc: Phil Turnbull <phil.turnbull@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 568f194e8b ("net: ppp: use
sk_unattached_filter api") causes sk_chk_filter() to be called twice when
setting a PPP pass or active filter. This applies to both the generic PPP
subsystem implemented by drivers/net/ppp/ppp_generic.c and the ISDN PPP
subsystem implemented by drivers/isdn/i4l/isdn_ppp.c. The first call is from
within get_filter(). The second one is through the call chain
ppp_ioctl() or isdn_ppp_ioctl()
--> sk_unattached_filter_create()
--> __sk_prepare_filter()
--> sk_chk_filter()
The first call from within get_filter() should be deleted as get_filter() is
called just before calling sk_unattached_filter_create() later on, which
eventually calls sk_chk_filter() anyway.
For 3.15.x, this proposed change is a bugfix rather than a pure optimization as
in that branch, sk_chk_filter() may replace filter codes by other codes which
are not recognized when executing sk_chk_filter() a second time. So with
3.15.x, if sk_chk_filter() is called twice, the second invocation may yield
EINVAL (this depends on the filter codes found in the filter to be set, but
because the replacement is done for frequently used codes, this is almost
always the case). The net effect is that setting pass and/or active PPP filters
does not work anymore, since sk_unattached_filter_create() always returns
EINVAL due to the second call to sk_chk_filter(), regardless whether the filter
was originally sane or not.
Signed-off-by: Christoph Schulz <develop@kristov.de>
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Napi id was not marked for gro_skb, this will lead rx busy loop won't
work correctly since they stack never try to call low latency receive
method because of a zero socket napi id. Fix this by marking napi id
for gro_skb.
The transaction rate of 1 byte netperf tcp_rr gets about 50% increased
(from 20531.68 to 30610.88).
Cc: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Obvious copy/paste error when I converted the ad_select to the new
option API. "lacp_rate" there should be "ad_select" so we can get the
proper value.
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: David S. Miller <davem@davemloft.net>
Fixes: 9e5f5eebe7 ("bonding: convert ad_select to use the new option
API")
Reported-by: Karim Scheik <karim.scheik@prisma-solutions.at>
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PPP channel MTU is used with Multilink PPP when ppp_mp_explode() (see
ppp_generic module) tries to determine how big a fragment might be. According
to RFC 1661, the MTU excludes the 2-byte PPP protocol field, see the
corresponding comment and code in ppp_mp_explode():
/*
* hdrlen includes the 2-byte PPP protocol field, but the
* MTU counts only the payload excluding the protocol field.
* (RFC1661 Section 2)
*/
mtu = pch->chan->mtu - (hdrlen - 2);
However, the pppoe module *does* include the PPP protocol field in the channel
MTU, which is wrong as it causes the PPP payload to be 1-2 bytes too big under
certain circumstances (one byte if PPP protocol compression is used, two
otherwise), causing the generated Ethernet packets to be dropped. So the pppoe
module has to subtract two bytes from the channel MTU. This error only
manifests itself when using Multilink PPP, as otherwise the channel MTU is not
used anywhere.
In the following, I will describe how to reproduce this bug. We configure two
pppd instances for multilink PPP over two PPPoE links, say eth2 and eth3, with
a MTU of 1492 bytes for each link and a MRRU of 2976 bytes. (This MRRU is
computed by adding the two link MTUs and subtracting the MP header twice, which
is 4 bytes long.) The necessary pppd statements on both sides are "multilink
mtu 1492 mru 1492 mrru 2976". On the client side, we additionally need "plugin
rp-pppoe.so eth2" and "plugin rp-pppoe.so eth3", respectively; on the server
side, we additionally need to start two pppoe-server instances to be able to
establish two PPPoE sessions, one over eth2 and one over eth3. We set the MTU
of the PPP network interface to the MRRU (2976) on both sides of the connection
in order to make use of the higher bandwidth. (If we didn't do that, IP
fragmentation would kick in, which we want to avoid.)
Now we send a ICMPv4 echo request with a payload of 2948 bytes from client to
server over the PPP link. This results in the following network packet:
2948 (echo payload)
+ 8 (ICMPv4 header)
+ 20 (IPv4 header)
---------------------
2976 (PPP payload)
These 2976 bytes do not exceed the MTU of the PPP network interface, so the
IP packet is not fragmented. Now the multilink PPP code in ppp_mp_explode()
prepends one protocol byte (0x21 for IPv4), making the packet one byte bigger
than the negotiated MRRU. So this packet would have to be divided in three
fragments. But this does not happen as each link MTU is assumed to be two bytes
larger. So this packet is diveded into two fragments only, one of size 1489 and
one of size 1488. Now we have for that bigger fragment:
1489 (PPP payload)
+ 4 (MP header)
+ 2 (PPP protocol field for the MP payload (0x3d))
+ 6 (PPPoE header)
--------------------------
1501 (Ethernet payload)
This packet exceeds the link MTU and is discarded.
If one configures the link MTU on the client side to 1501, one can see the
discarded Ethernet frames with tcpdump running on the client. A
ping -s 2948 -c 1 192.168.15.254
leads to the smaller fragment that is correctly received on the server side:
(tcpdump -vvvne -i eth3 pppoes and ppp proto 0x3d)
52:54:00:ad:87:fd > 52:54:00:79:5c:d0, ethertype PPPoE S (0x8864),
length 1514: PPPoE [ses 0x3] MLPPP (0x003d), length 1494: seq 0x000,
Flags [end], length 1492
and to the bigger fragment that is not received on the server side:
(tcpdump -vvvne -i eth2 pppoes and ppp proto 0x3d)
52:54:00:70:9e:89 > 52:54:00:5d:6f:b0, ethertype PPPoE S (0x8864),
length 1515: PPPoE [ses 0x5] MLPPP (0x003d), length 1495: seq 0x000,
Flags [begin], length 1493
With the patch below, we correctly obtain three fragments:
52:54:00:ad:87:fd > 52:54:00:79:5c:d0, ethertype PPPoE S (0x8864),
length 1514: PPPoE [ses 0x1] MLPPP (0x003d), length 1494: seq 0x000,
Flags [begin], length 1492
52:54:00:70:9e:89 > 52:54:00:5d:6f:b0, ethertype PPPoE S (0x8864),
length 1514: PPPoE [ses 0x1] MLPPP (0x003d), length 1494: seq 0x000,
Flags [none], length 1492
52:54:00:ad:87:fd > 52:54:00:79:5c:d0, ethertype PPPoE S (0x8864),
length 27: PPPoE [ses 0x1] MLPPP (0x003d), length 7: seq 0x000,
Flags [end], length 5
And the ICMPv4 echo request is successfully received at the server side:
IP (tos 0x0, ttl 64, id 21925, offset 0, flags [DF], proto ICMP (1),
length 2976)
192.168.222.2 > 192.168.15.254: ICMP echo request, id 30530, seq 0,
length 2956
The bug was introduced in commit c9aa689537
("[PPPOE]: Advertise PPPoE MTU") from the very beginning. This patch applies
to 3.10 upwards but the fix can be applied (with minor modifications) to
kernels as old as 2.6.32.
Signed-off-by: Christoph Schulz <develop@kristov.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code in neigh_sysctl_register() relies on a specific layout of
struct neigh_table, namely that the 'gc_*' variables are directly
following the 'parms' member in a specific order. The code, though,
expresses this in the most ugly way.
Get rid of the ugly casts and use the 'tbl' pointer to get a handle to
the table. This way we can refer to the 'gc_*' variables directly.
Similarly seen in the grsecurity patch, written by Brad Spengler.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Brad Spengler <spender@grsecurity.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When quota is on, it is expected that unused quota inodes have a
value of NULLFSINO. The changes to support a separate project quota
in 3.12 broken this rule for non-project quota inode enabled
filesystem, as the code now refuses to write the group quota inode
if neither group or project quotas are enabled. This regression was
introduced by commit d892d58 ("xfs: Start using pquotaino from the
superblock").
In this case, we should be writing NULLFSINO rather than nothing to
ensure that we leave the group quota inode in a valid state while
quotas are enabled.
Failure to do so doesn't cause a current kernel to break - the
separate project quota inodes introduced translation code to always
treat a zero inode as NULLFSINO. This was introduced by commit
0102629 ("xfs: Initialize all quota inodes to be NULLFSINO") with is
also in 3.12 but older kernels do not do this and hence taking a
filesystem back to an older kernel can result in quotas failing
initialisation at mount time. When that happens, we see this in
dmesg:
[ 1649.215390] XFS (sdb): Mounting Filesystem
[ 1649.316894] XFS (sdb): Failed to initialize disk quotas.
[ 1649.316902] XFS (sdb): Ending clean mount
By ensuring that we write NULLFSINO to quota inodes that aren't
active, we avoid this problem. We have to be really careful when
determining if the quota inodes are active or not, because we don't
want to write a NULLFSINO if the quota inodes are active and we
simply aren't updating them.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
While working on some other SCTP code, I noticed that some
structures shared with user space are leaking uninitialized
stack or heap buffer. In particular, struct sctp_sndrcvinfo
has a 2 bytes hole between .sinfo_flags and .sinfo_ppid that
remains unfilled by us in sctp_ulpevent_read_sndrcvinfo() when
putting this into cmsg. But also struct sctp_remote_error
contains a 2 bytes hole that we don't fill but place into a skb
through skb_copy_expand() via sctp_ulpevent_make_remote_error().
Both structures are defined by the IETF in RFC6458:
* Section 5.3.2. SCTP Header Information Structure:
The sctp_sndrcvinfo structure is defined below:
struct sctp_sndrcvinfo {
uint16_t sinfo_stream;
uint16_t sinfo_ssn;
uint16_t sinfo_flags;
<-- 2 bytes hole -->
uint32_t sinfo_ppid;
uint32_t sinfo_context;
uint32_t sinfo_timetolive;
uint32_t sinfo_tsn;
uint32_t sinfo_cumtsn;
sctp_assoc_t sinfo_assoc_id;
};
* 6.1.3. SCTP_REMOTE_ERROR:
A remote peer may send an Operation Error message to its peer.
This message indicates a variety of error conditions on an
association. The entire ERROR chunk as it appears on the wire
is included in an SCTP_REMOTE_ERROR event. Please refer to the
SCTP specification [RFC4960] and any extensions for a list of
possible error formats. An SCTP error notification has the
following format:
struct sctp_remote_error {
uint16_t sre_type;
uint16_t sre_flags;
uint32_t sre_length;
uint16_t sre_error;
<-- 2 bytes hole -->
sctp_assoc_t sre_assoc_id;
uint8_t sre_data[];
};
Fix this by setting both to 0 before filling them out. We also
have other structures shared between user and kernel space in
SCTP that contains holes (e.g. struct sctp_paddrthlds), but we
copy that buffer over from user space first and thus don't need
to care about it in that cases.
While at it, we can also remove lengthy comments copied from
the draft, instead, we update the comment with the correct RFC
number where one can look it up.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 38aecea0cc.
This breaks Haswell Thinkpad + Lenovo dock in SST mode with a HDMI monitor attached.
Before this we can 1920x1200 mode, after this we only ever get 1024x768, and
a lot of deferring.
This didn't revert clean, but this should be fine.
bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1117008
Cc: stable@vger.kernel.org # v3.15
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The allocation stack switch at xfs_bmapi_allocate() has served it's
purpose, but is no longer a sufficient solution to the stack usage
problem we have in the XFS allocation path.
Whilst the kernel stack size is now 16k, that is not a valid reason
for undoing all our "keep stack usage down" modifications. What it
does allow us to do is have the freedom to refine and perfect the
modifications knowing that if we get it wrong it won't blow up in
our faces - we have a safety net now.
This is important because we still have the issue of older kernels
having smaller stacks and that they are still supported and are
demonstrating a wide range of different stack overflows. Red Hat
has several open bugs for allocation based stack overflows from
directory modifications and direct IO block allocation and these
problems still need to be solved. If we can solve them upstream,
then distro's won't need to bake their own unique solutions.
To that end, I've observed that every allocation based stack
overflow report has had a specific characteristic - it has happened
during or directly after a bmap btree block split. That event
requires a new block to be allocated to the tree, and so we
effectively stack one allocation stack on top of another, and that's
when we get into trouble.
A further observation is that bmap btree block splits are much rarer
than writeback allocation - over a range of different workloads I've
observed the ratio of bmap btree inserts to splits ranges from 100:1
(xfstests run) to 10000:1 (local VM image server with sparse files
that range in the hundreds of thousands to millions of extents).
Either way, bmap btree split events are much, much rarer than
allocation events.
Finally, we have to move the kswapd state to the allocation workqueue
work when allocation is done on behalf of kswapd. This is proving to
cause significant perturbation in performance under memory pressure
and appears to be generating allocation deadlock warnings under some
workloads, so avoiding the use of a workqueue for the majority of
kswapd writeback allocation will minimise the impact of such
behaviour.
Hence it makes sense to move the stack switch to xfs_btree_split()
and only do it for bmap btree splits. Stack switches during
allocation will be much rarer, so there won't be significant
performacne overhead caused by switching stacks. The worse case
stack from all allocation paths will be split, not just writeback.
And the majority of memory allocations will be done in the correct
context (e.g. kswapd) without causing additional latency, and so we
simplify the memory reclaim interactions between processes,
workqueues and kswapd.
The worst stack I've been able to generate with this patch in place
is 5600 bytes deep. It's very revealing because we exit XFS at:
37) 1768 64 kmem_cache_alloc+0x13b/0x170
about 1800 bytes of stack consumed, and the remaining 3800 bytes
(and 36 functions) is memory reclaim, swap and the IO stack. And
this occurs in the inode allocation from an open(O_CREAT) syscall,
not writeback.
The amount of stack being used is much less than I've previously be
able to generate - fs_mark testing has been able to generate stack
usage of around 7k without too much trouble; with this patch it's
only just getting to 5.5k. This is primarily because the metadata
allocation paths (e.g. directory blocks) are no longer causing
double splits on the same stack, and hence now stack tracing is
showing swapping being the worst stack consumer rather than XFS.
Performance of fs_mark inode create workloads is unchanged.
Performance of fs_mark async fsync workloads is consistently good
with context switches reduced by around 150,000/s (30%).
Performance of dbench, streaming IO and postmark is unchanged.
Allocation deadlock warnings have not been seen on the workloads
that generated them since adding this patch.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This reverts commit 1f6d64829d.
This commit resulted in regressions in performance in low
memory situations where kswapd was doing writeback of delayed
allocation blocks. It resulted in significant parallelism of the
kswapd work and with the special kswapd flags meant that hundreds of
active allocation could dip into kswapd specific memory reserves and
avoid being throttled. This cause a large amount of performance
variation, as well as random OOM-killer invocations that didn't
previously exist.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
init_espfix_ap() is currently off by one level when informing hypervisor
that allocated pages will be used for ministacks' page tables.
The most immediate effect of this on a PV guest is that if
'stack_page = __get_free_page()' returns a non-zeroed-out page the hypervisor
will refuse to use it for a page table (which it shouldn't be anyway). This will
result in warnings by both Xen and Linux.
More importantly, a subsequent write to that page (again, by a PV guest) is
likely to result in fatal page fault.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: http://lkml.kernel.org/r/1404926298-5565-1-git-send-email-boris.ostrovsky@oracle.com
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
which, apart from reducing code duplication also stops the arm64 stub
being rebuilt every time make is invoked - Ard Biesheuvel
* Fix the EFI fdt code to not report a boot error if UEFI is
unavailable since booting without UEFI parameters is a valid use case
for non-UEFI platforms - Catalin Marinas
* Include a .bss section in the EFI boot stub PE/COFF headers to fix a
memory corruption bug - Michael Brown
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Merge tag 'efi-urgent' into x86/urgent
* Remove a duplicate copy of linux_banner from the arm64 EFI stub
which, apart from reducing code duplication also stops the arm64 stub
being rebuilt every time make is invoked - Ard Biesheuvel
* Fix the EFI fdt code to not report a boot error if UEFI is
unavailable since booting without UEFI parameters is a valid use case
for non-UEFI platforms - Catalin Marinas
* Include a .bss section in the EFI boot stub PE/COFF headers to fix a
memory corruption bug - Michael Brown
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This reverts commit 886129a8ee (ACPI / video: change acpi-video
brightness_switch_enabled default to 0) as it is reported to cause
problems to happen.
Fixes: 886129a8ee (ACPI / video: change acpi-video brightness_switch_enabled default to 0)
Link: http://marc.info/?l=linux-acpi&m=140534286826819&w=2
Reported by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Dashes are not allowed in hwmon name attributes.
Use "da9055" instead of "da9055-hwmon".
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Dashes are not allowed in hwmon name attributes.
Use "da9052" instead of "da9052-hwmon".
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
commit 98ec77397a
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Wed Apr 30 17:43:01 2014 +0300
drm/i915: Make primary_enabled match the actual hardware state
introduced more accurate tracking of the primary plane and some
checks. It missed the plane->pipe reassignement code for gen2/3
though, which the checks caught and resulted in WARNING backtraces.
Since we only use this path if the plane is on and on the wrong pipe
we can just always set the tracking bit to "enabled".
Reported-and-tested-by: Paul Bolle <pebolle@tiscali.nl>
Cc: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
As of commit f8567a3845 it is now possible to
have put_reqs_available() called from irq context. While put_reqs_available()
is per cpu, it did not protect itself from interrupts on the same CPU. This
lead to aio_complete() corrupting the available io requests count when run
under a heavy O_DIRECT workloads as reported by Robert Elliott. Fix this by
disabling irq updates around the per cpu batch updates of reqs_available.
Many thanks to Robert and folks for testing and tracking this down.
Reported-by: Robert Elliot <Elliott@hp.com>
Tested-by: Robert Elliot <Elliott@hp.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: Jens Axboe <axboe@kernel.dk>, Christoph Hellwig <hch@infradead.org>
Cc: stable@vger.kenel.org
The hwrng core asks for random data in the hwrng_register() call itself
from commit d9e7972619. This doesn't play well with virtio -- the
DRIVER_OK bit is only set by virtio core on a successful probe, and
we're not yet out of our probe routine when this call is made. This
causes the host to not acknowledge any requests we put in the virtqueue,
and the insmod or kernel boot process just waits for data to arrive from
the host, which never happens.
CC: Kees Cook <keescook@chromium.org>
CC: Jason Cooper <jason@lakedaemon.net>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: <stable@vger.kernel.org> # For v3.15+
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit d9e7972619 "hwrng: add randomness to system from rng sources"
added a call to rng_get_data() from the hwrng_register() function.
However, some rng devices need initialization before data can be read
from them.
This commit makes the call to rng_get_data() depend on no init fn
pointer being registered by the device. If an init function is
registered, this call is made after device init.
CC: Kees Cook <keescook@chromium.org>
CC: Jason Cooper <jason@lakedaemon.net>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: <stable@vger.kernel.org> # For v3.15+
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We got a regression report for 3.15.x kernels, and this turned out to
be triggered by the fix for stream assignment order. On reporter's
machine with Intel controller (8086:1e20) + VIA VT1802 codec, the
first playback slot can't work with speaker outputs.
But the original commit was actually a fix for AMD controllers where
no proper GCAP value is returned, we shouldn't revert the whole
commit. Instead, in this patch, a new flag is introduced to determine
the stream assignment order, and follow the old behavior for Intel
controllers.
Fixes: dcb32ecd9a ('ALSA: hda - Do not assign streams in reverse order')
Reported-and-tested-by: Steven Newbury <steve@snewbury.org.uk>
Cc: <stable@vger.kernel.org> [v3.15+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
commit c675949ec5
drm/i915: do not setup backlight if not available according to VBT
caused a regression on the HP Chromebook 14 (with Celeron 2955U CPU),
which has a misconfigured VBT. Apply quirk to ignore the VBT backlight
presence check during backlight setup.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79813
Signed-off-by: Scot Doyle <lkml14@scotdoyle.com>
Tested-by: Stefan Nagy <public@stefan-nagy.at>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This reverts commit 773875bfb6.
It is very much needed and the lack of dithering has been reported by
a large list of people with various gen2/3 hardware.
Also, the original patch was complete non-sense since the WARNING
backtraces in the references bugzilla are about
gmch_pfit.lvds_border_bits mismatch, not at all about the dither bit.
That one seems to work.
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Hans de Bruin <jmdebruin@xmsnet.nl>
Cc: stable@vger.kernel.org
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
RGMII_MODE_EN bit was defined to 0, while it is actually 6. It was not
much of a problem on older designs where this was a no-op, and the RGMII
data-path would always be enabled, but newer GENET controllers need to
explicitely enable their RGMII data-pad using this bit.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This family of chips was long ago supported by the pre-cfi driver.
CFI code tested on several Zaurus SL-5500 (Collie) 2x16 on 32 bit bus.
Function is_LH28F640BF() mimics is_m29ew() from cmdset_0002.c
Buffer write fixes as seen in 2007 patch c/o
Anti Sullin <anti.sullin <at> artecdesign.ee>
http://comments.gmane.org/gmane.linux.ports.arm.kernel/36733
[Brian: this patch is semi-urgent, because the following patch switches
to using CFI detection for a chip which (until now) is unsupported by
the CFI driver
9218310 ARM: 8084/1: sa1100: collie: revert back to cfi_probe
]
Signed-off-by: Andrea Adami <andrea.adami@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
In commit 67a9ad9b8a ("mtd: nand: Warn the user if the selected ECC
strength is too weak"), a check was added to inform the user when the
ECC used for a NAND device is weaker than the recommended ECC
advertised by the NAND chip. However, the warning uses WARN_ON(),
which has two undesirable side-effects:
- It just prints to the kernel log the fact that there is a warning
in this file, at this line, but it doesn't explain anything about
the warning itself.
- It dumps a stack trace which is very noisy, for something that the
user is most likely not able to fix. If a certain ECC used by the
kernel is weaker than the advertised one, it's most likely to make
sure the kernel uses an ECC that is compatible with the one used by
the bootloader, and changing the bootloader may not necessarily be
easy. Therefore, normal users would not be able to do anything to
fix this very noisy warning, and will have to suffer from it at
every kernel boot. At least every time I see this stack trace in my
kernel boot log, I wonder what new thing is broken, just to realize
that it's once again this NAND ECC warning.
Therefore, this commit turns:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1 at /home/thomas/projets/linux-2.6/drivers/mtd/nand/nand_base.c:4051 nand_scan_tail+0x538/0x780()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 3.16.0-rc3-dirty #4
[<c000e3dc>] (unwind_backtrace) from [<c000bee4>] (show_stack+0x10/0x14)
[<c000bee4>] (show_stack) from [<c0018180>] (warn_slowpath_common+0x6c/0x8c)
[<c0018180>] (warn_slowpath_common) from [<c001823c>] (warn_slowpath_null+0x1c/0x24)
[<c001823c>] (warn_slowpath_null) from [<c02c50cc>] (nand_scan_tail+0x538/0x780)
[<c02c50cc>] (nand_scan_tail) from [<c0639f78>] (orion_nand_probe+0x224/0x2e4)
[<c0639f78>] (orion_nand_probe) from [<c026da00>] (platform_drv_probe+0x18/0x4c)
[<c026da00>] (platform_drv_probe) from [<c026c1f4>] (really_probe+0x80/0x218)
[<c026c1f4>] (really_probe) from [<c026c47c>] (__driver_attach+0x98/0x9c)
[<c026c47c>] (__driver_attach) from [<c026a8f0>] (bus_for_each_dev+0x64/0x94)
[<c026a8f0>] (bus_for_each_dev) from [<c026bae4>] (bus_add_driver+0x144/0x1ec)
[<c026bae4>] (bus_add_driver) from [<c026cb00>] (driver_register+0x78/0xf8)
[<c026cb00>] (driver_register) from [<c026da5c>] (platform_driver_probe+0x20/0xb8)
[<c026da5c>] (platform_driver_probe) from [<c00088b8>] (do_one_initcall+0x80/0x1d8)
[<c00088b8>] (do_one_initcall) from [<c0620c9c>] (kernel_init_freeable+0xf4/0x1b4)
[<c0620c9c>] (kernel_init_freeable) from [<c049a098>] (kernel_init+0x8/0xec)
[<c049a098>] (kernel_init) from [<c00095f0>] (ret_from_fork+0x14/0x24)
---[ end trace 62f87d875aceccb4 ]---
Into the much shorter, and much more useful:
nand: WARNING: MT29F2G08ABAEAWP: the ECC used on your system is too weak compared to the one required by the NAND chip
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
* Fix incorrect handling of the iio_event_spec mask_shared_by_type
bitmap. The point of this was to allow multiple channels to specify
elements that lead to the same sysfs attribute. A but in the handling
meant that this failed. The handling is modified to be similar to that
used for the main IIO info_mask_shared_by_type which works correclty.
* The acceleration scale factors reported by the mma8452 driver gave
accelerations in g, wherease the IIO ABI is in m/s^2. The fix simply
corrects the reported scale factors.
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Merge tag 'iio-fixes-for-3.16d' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus
Jonathan writes:
4th set of fixes for IIO in the 3.16 cycle
* Fix incorrect handling of the iio_event_spec mask_shared_by_type
bitmap. The point of this was to allow multiple channels to specify
elements that lead to the same sysfs attribute. A but in the handling
meant that this failed. The handling is modified to be similar to that
used for the main IIO info_mask_shared_by_type which works correclty.
* The acceleration scale factors reported by the mma8452 driver gave
accelerations in g, wherease the IIO ABI is in m/s^2. The fix simply
corrects the reported scale factors.
