net: do not pretend FRAGLIST support

[ Upstream commit 28e24c62ab3062e965ef1b3bcc244d50aee7fa85 ]

Few network drivers really supports frag_list : virtual drivers.

Some drivers wrongly advertise NETIF_F_FRAGLIST feature.

If skb with a frag_list is given to them, packet on the wire will be
corrupt.

Remove this flag, as core networking stack will make sure to
provide packets that can be sent without corruption.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Cc: Anirudha Sarangi <anirudh@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
rds: prevent BUG_ON triggered on congestion update to loopback

[ Upstream commit 18fc25c94eadc52a42c025125af24657a93638c0 ]

After congestion update on a local connection, when rds_ib_xmit returns
less bytes than that are there in the message, rds_send_xmit calls
back rds_ib_xmit with an offset that causes BUG_ON(off & RDS_FRAG_SIZE)
to trigger.

For a 4Kb PAGE_SIZE rds_ib_xmit returns min(8240,4096)=4096 when actually
the message contains 8240 bytes. rds_send_xmit thinks there is more to send
and calls rds_ib_xmit again with a data offset "off" of 4096-48(rds header)
=4048 bytes thus hitting the BUG_ON(off & RDS_FRAG_SIZE) [RDS_FRAG_SIZE=4k].

The commit 6094628bfd94323fc1cea05ec2c6affd98c18f7f
"rds: prevent BUG_ON triggering on congestion map updates" introduced
this regression. That change was addressing the triggering of a different
BUG_ON in rds_send_xmit() on PowerPC architecture with 64Kbytes PAGE_SIZE:
 	BUG_ON(ret != 0 &&
    		 conn->c_xmit_sg == rm->data.op_nents);
This was the sequence it was going through:
(rds_ib_xmit)
/* Do not send cong updates to IB loopback */
if (conn->c_loopback
   && rm->m_inc.i_hdr.h_flags & RDS_FLAG_CONG_BITMAP) {
  	rds_cong_map_updated(conn->c_fcong, ~(u64) 0);
    	return sizeof(struct rds_header) + RDS_CONG_MAP_BYTES;
}
rds_ib_xmit returns 8240
rds_send_xmit:
  c_xmit_data_off = 0 + 8240 - 48 (rds header accounted only the first time)
   		 = 8192
  c_xmit_data_off < 65536 (sg->length), so calls rds_ib_xmit again
rds_ib_xmit returns 8240
rds_send_xmit:
  c_xmit_data_off = 8192 + 8240 = 16432, calls rds_ib_xmit again
  and so on (c_xmit_data_off 24672,32912,41152,49392,57632)
rds_ib_xmit returns 8240
On this iteration this sequence causes the BUG_ON in rds_send_xmit:
    while (ret) {
    	tmp = min_t(int, ret, sg->length - conn->c_xmit_data_off);
    	[tmp = 65536 - 57632 = 7904]
    	conn->c_xmit_data_off += tmp;
    	[c_xmit_data_off = 57632 + 7904 = 65536]
    	ret -= tmp;
    	[ret = 8240 - 7904 = 336]
    	if (conn->c_xmit_data_off == sg->length) {
    		conn->c_xmit_data_off = 0;
    		sg++;
    		conn->c_xmit_sg++;
    		BUG_ON(ret != 0 &&
    			conn->c_xmit_sg == rm->data.op_nents);
    		[c_xmit_sg = 1, rm->data.op_nents = 1]

What the current fix does:
Since the congestion update over loopback is not actually transmitted
as a message, all that rds_ib_xmit needs to do is let the caller think
the full message has been transmitted and not return partial bytes.
It will return 8240 (RDS_CONG_MAP_BYTES+48) when PAGE_SIZE is 4Kb.
And 64Kb+48 when page size is 64Kb.

Reported-by: Josh Hunt <joshhunt00@gmail.com>
Tested-by: Honggang Li <honli@redhat.com>
Acked-by: Bang Nguyen <bang.nguyen@oracle.com>
Signed-off-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: don't count addrconf generated routes against gc limit

[ Upstream commit a3300ef4bbb1f1e33ff0400e1e6cf7733d988f4f ]

Brett Ciphery reported that new ipv6 addresses failed to get installed
because the addrconf generated dsts where counted against the dst gc
limit. We don't need to count those routes like we currently don't count
administratively added routes.

Because the max_addresses check enforces a limit on unbounded address
generation first in case someone plays with router advertisments, we
are still safe here.

Reported-by: Brett Ciphery <brett.ciphery@windriver.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: drop_monitor: fix the value of maxattr

[ Upstream commit d323e92cc3f4edd943610557c9ea1bb4bb5056e8 ]

maxattr in genl_family should be used to save the max attribute
type, but not the max command type. Drop monitor doesn't support
any attributes, so we should leave it as zero.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tg3: Initialize REG_BASE_ADDR at PCI config offset 120 to 0

[ Upstream commit 388d3335575f4c056dcf7138a30f1454e2145cd8 ]

The new tg3 driver leaves REG_BASE_ADDR (PCI config offset 120)
uninitialized. From power on reset this register may have garbage in it. The
Register Base Address register defines the device local address of a
register. The data pointed to by this location is read or written using
the Register Data register (PCI config offset 128). When REG_BASE_ADDR has
garbage any read or write of Register Data Register (PCI 128) will cause the
PCI bus to lock up. The TCO watchdog will fire and bring down the system.

Signed-off-by: Nat Gurumoorthy <natg@google.com>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: unix: allow bind to fail on mutex lock

[ Upstream commit 37ab4fa7844a044dc21fde45e2a0fc2f3c3b6490 ]

This is similar to the set_peek_off patch where calling bind while the
socket is stuck in unix_dgram_recvmsg() will block and cause a hung task
spew after a while.

This is also the last place that did a straightforward mutex_lock(), so
there shouldn't be any more of these patches.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: inet_diag: zero out uninitialized idiag_{src,dst} fields

[ Upstream commit b1aac815c0891fe4a55a6b0b715910142227700f ]

Jakub reported while working with nlmon netlink sniffer that parts of
the inet_diag_sockid are not initialized when r->idiag_family != AF_INET6.
That is, fields of r->id.idiag_src[1 ... 3], r->id.idiag_dst[1 ... 3].

In fact, it seems that we can leak 6 * sizeof(u32) byte of kernel [slab]
memory through this. At least, in udp_dump_one(), we allocate a skb in ...

  rep = nlmsg_new(sizeof(struct inet_diag_msg) + ..., GFP_KERNEL);

... and then pass that to inet_sk_diag_fill() that puts the whole struct
inet_diag_msg into the skb, where we only fill out r->id.idiag_src[0],
r->id.idiag_dst[0] and leave the rest untouched:

  r->id.idiag_src[0] = inet->inet_rcv_saddr;
  r->id.idiag_dst[0] = inet->inet_daddr;

struct inet_diag_msg embeds struct inet_diag_sockid that is correctly /
fully filled out in IPv6 case, but for IPv4 not.

So just zero them out by using plain memset (for this little amount of
bytes it's probably not worth the extra check for idiag_family == AF_INET).

Similarly, fix also other places where we fill that out.

Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drivers/net/hamradio: Integer overflow in hdlcdrv_ioctl()

[ Upstream commit e9db5c21d3646a6454fcd04938dd215ac3ab620a ]

The local variable 'bi' comes from userspace. If userspace passed a
large number to 'bi.data.calibrate', there would be an integer overflow
in the following line:
	s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;

Signed-off-by: Wenliang Fan <fanwlexca@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
hamradio/yam: fix info leak in ioctl

[ Upstream commit 8e3fbf870481eb53b2d3a322d1fc395ad8b367ed ]

The yam_ioctl() code fails to initialise the cmd field
of the struct yamdrv_ioctl_cfg. Add an explicit memset(0)
before filling the structure to avoid the 4-byte info leak.

Signed-off-by: Salva Peiró <speiro@ai2.upv.es>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
rds: prevent dereference of a NULL device

[ Upstream commit c2349758acf1874e4c2b93fe41d072336f1a31d0 ]

Binding might result in a NULL device, which is dereferenced
causing this BUG:

[ 1317.260548] BUG: unable to handle kernel NULL pointer dereference at 000000000000097
4
[ 1317.261847] IP: [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110
[ 1317.263315] PGD 418bcb067 PUD 3ceb21067 PMD 0
[ 1317.263502] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 1317.264179] Dumping ftrace buffer:
[ 1317.264774]    (ftrace buffer empty)
[ 1317.265220] Modules linked in:
[ 1317.265824] CPU: 4 PID: 836 Comm: trinity-child46 Tainted: G        W    3.13.0-rc4-
next-20131218-sasha-00013-g2cebb9b-dirty #4159
[ 1317.267415] task: ffff8803ddf33000 ti: ffff8803cd31a000 task.ti: ffff8803cd31a000
[ 1317.268399] RIP: 0010:[<ffffffff84225f52>]  [<ffffffff84225f52>] rds_ib_laddr_check+
0x82/0x110
[ 1317.269670] RSP: 0000:ffff8803cd31bdf8  EFLAGS: 00010246
[ 1317.270230] RAX: 0000000000000000 RBX: ffff88020b0dd388 RCX: 0000000000000000
[ 1317.270230] RDX: ffffffff8439822e RSI: 00000000000c000a RDI: 0000000000000286
[ 1317.270230] RBP: ffff8803cd31be38 R08: 0000000000000000 R09: 0000000000000000
[ 1317.270230] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
[ 1317.270230] R13: 0000000054086700 R14: 0000000000a25de0 R15: 0000000000000031
[ 1317.270230] FS:  00007ff40251d700(0000) GS:ffff88022e200000(0000) knlGS:000000000000
0000
[ 1317.270230] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1317.270230] CR2: 0000000000000974 CR3: 00000003cd478000 CR4: 00000000000006e0
[ 1317.270230] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1317.270230] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000090602
[ 1317.270230] Stack:
[ 1317.270230]  0000000054086700 5408670000a25de0 5408670000000002 0000000000000000
[ 1317.270230]  ffffffff84223542 00000000ea54c767 0000000000000000 ffffffff86d26160
[ 1317.270230]  ffff8803cd31be68 ffffffff84223556 ffff8803cd31beb8 ffff8800c6765280
[ 1317.270230] Call Trace:
[ 1317.270230]  [<ffffffff84223542>] ? rds_trans_get_preferred+0x42/0xa0
[ 1317.270230]  [<ffffffff84223556>] rds_trans_get_preferred+0x56/0xa0
[ 1317.270230]  [<ffffffff8421c9c3>] rds_bind+0x73/0xf0
[ 1317.270230]  [<ffffffff83e4ce62>] SYSC_bind+0x92/0xf0
[ 1317.270230]  [<ffffffff812493f8>] ? context_tracking_user_exit+0xb8/0x1d0
[ 1317.270230]  [<ffffffff8119313d>] ? trace_hardirqs_on+0xd/0x10
[ 1317.270230]  [<ffffffff8107a852>] ? syscall_trace_enter+0x32/0x290
[ 1317.270230]  [<ffffffff83e4cece>] SyS_bind+0xe/0x10
[ 1317.270230]  [<ffffffff843a6ad0>] tracesys+0xdd/0xe2
[ 1317.270230] Code: 00 8b 45 cc 48 8d 75 d0 48 c7 45 d8 00 00 00 00 66 c7 45 d0 02 00
89 45 d4 48 89 df e8 78 49 76 ff 41 89 c4 85 c0 75 0c 48 8b 03 <80> b8 74 09 00 00 01 7
4 06 41 bc 9d ff ff ff f6 05 2a b6 c2 02
[ 1317.270230] RIP  [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110
[ 1317.270230]  RSP <ffff8803cd31bdf8>
[ 1317.270230] CR2: 0000000000000974

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: rose: restore old recvmsg behavior

[ Upstream commit f81152e35001e91997ec74a7b4e040e6ab0acccf ]

recvmsg handler in net/rose/af_rose.c performs size-check ->msg_namelen.

After commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c
(net: rework recvmsg handler msg_name and msg_namelen logic), we now
always take the else branch due to namelen being initialized to 0.

Digging in netdev-vger-cvs git repo shows that msg_namelen was
initialized with a fixed-size since at least 1995, so the else branch
was never taken.

Compile tested only.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
vlan: Fix header ops passthru when doing TX VLAN offload.

[ Upstream commit 2205369a314e12fcec4781cc73ac9c08fc2b47de ]

When the vlan code detects that the real device can do TX VLAN offloads
in hardware, it tries to arrange for the real device's header_ops to
be invoked directly.

But it does so illegally, by simply hooking the real device's
header_ops up to the VLAN device.

This doesn't work because we will end up invoking a set of header_ops
routines which expect a device type which matches the real device, but
will see a VLAN device instead.

Fix this by providing a pass-thru set of header_ops which will arrange
to pass the proper real device instead.

To facilitate this add a dev_rebuild_header().  There are
implementations which provide a ->cache and ->create but not a
->rebuild (f.e. PLIP).  So we need a helper function just like
dev_hard_header() to avoid crashes.

Use this helper in the one existing place where the
header_ops->rebuild was being invoked, the neighbour code.

With lots of help from Florian Westphal.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: llc: fix use after free in llc_ui_recvmsg

[ Upstream commit 4d231b76eef6c4a6bd9c96769e191517765942cb ]

While commit 30a584d944fb fixes datagram interface in LLC, a use
after free bug has been introduced for SOCK_STREAM sockets that do
not make use of MSG_PEEK.

The flow is as follow ...

  if (!(flags & MSG_PEEK)) {
    ...
    sk_eat_skb(sk, skb, false);
    ...
  }
  ...
  if (used + offset < skb->len)
    continue;

... where sk_eat_skb() calls __kfree_skb(). Therefore, cache
original length and work on skb_len to check partial reads.

Fixes: 30a584d944fb ("[LLX]: SOCK_DGRAM interface fixes")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
bridge: use spin_lock_bh() in br_multicast_set_hash_max

[ Upstream commit fe0d692bbc645786bce1a98439e548ae619269f5 ]

br_multicast_set_hash_max() is called from process context in
net/bridge/br_sysfs_br.c by the sysfs store_hash_max() function.

br_multicast_set_hash_max() calls spin_lock(&br->multicast_lock),
which can deadlock the CPU if a softirq that also tries to take the
same lock interrupts br_multicast_set_hash_max() while the lock is
held .  This can happen quite easily when any of the bridge multicast
timers expire, which try to take the same lock.

The fix here is to use spin_lock_bh(), preventing other softirqs from
executing on this CPU.

Steps to reproduce:

1. Create a bridge with several interfaces (I used 4).
2. Set the "multicast query interval" to a low number, like 2.
3. Enable the bridge as a multicast querier.
4. Repeatedly set the bridge hash_max parameter via sysfs.

  # brctl addbr br0
  # brctl addif br0 eth1 eth2 eth3 eth4
  # brctl setmcqi br0 2
  # brctl setmcquerier br0 1

  # while true ; do echo 4096 > /sys/class/net/br0/bridge/hash_max; done

Signed-off-by: Curt Brune <curt@cumulusnetworks.com>
Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
bnx2x: fix DMA unmapping of TSO split BDs

[ Upstream commit 95e92fd40c967c363ad66b2fd1ce4dcd68132e54 ]

bnx2x triggers warnings with CONFIG_DMA_API_DEBUG=y:

  WARNING: CPU: 0 PID: 2253 at lib/dma-debug.c:887 check_unmap+0xf8/0x920()
  bnx2x 0000:28:00.0: DMA-API: device driver frees DMA memory with
  different size [device address=0x00000000da2b389e] [map size=1490 bytes]
  [unmap size=66 bytes]

The reason is that bnx2x splits a TSO BD into two BDs (headers + data)
using one DMA mapping for both, but it uses only the length of the first
BD when unmapping.

This patch fixes the bug by unmapping the whole length of the two BDs.

Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
inet_diag: fix inet_diag_dump_icsk() timewait socket state logic

[ Based upon upstream commit 70315d22d3c7383f9a508d0aab21e2eb35b2303a ]

Fix inet_diag_dump_icsk() to reflect the fact that both TIME_WAIT and
FIN_WAIT2 connections are represented by inet_timewait_sock (not just
TIME_WAIT). Thus:

(a) We need to iterate through the time_wait buckets if the user wants
either TIME_WAIT or FIN_WAIT2. (Before fixing this, "ss -nemoi state
fin-wait-2" would not return any sockets, even if there were some in
FIN_WAIT2.)

(b) We need to check tw_substate to see if the user wants to dump
sockets in the particular substate (TIME_WAIT or FIN_WAIT2) that a
given connection is in. (Before fixing this, "ss -nemoi state
time-wait" would actually return sockets in state FIN_WAIT2.)

An analogous fix is in v3.13: 70315d22d3c7383f9a508d0aab21e2eb35b2303a
("inet_diag: fix inet_diag_dump_icsk() to use correct state for
timewait sockets") but that patch is quite different because 3.13 code
is very different in this area due to the unification of TCP hash
tables in 05dbc7b ("tcp/dccp: remove twchain") in v3.13-rc1.

I tested that this applies cleanly between v3.3 and v3.12, and tested
that it works in both 3.3 and 3.12. It does not apply cleanly to 3.2
and earlier (though it makes semantic sense), and semantically is not
the right fix for 3.13 and beyond (as mentioned above).

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: avoid reference counter overflows on fib_rules in multicast forwarding

[ Upstream commit 95f4a45de1a0f172b35451fc52283290adb21f6e ]

Bob Falken reported that after 4G packets, multicast forwarding stopped
working. This was because of a rule reference counter overflow which
freed the rule as soon as the overflow happend.

This patch solves this by adding the FIB_LOOKUP_NOREF flag to
fib_rules_lookup calls. This is safe even from non-rcu locked sections
as in this case the flag only implies not taking a reference to the rule,
which we don't need at all.

Rules only hold references to the namespace, which are guaranteed to be
available during the call of the non-rcu protected function reg_vif_xmit
because of the interface reference which itself holds a reference to
the net namespace.

Fixes: f0ad0860d01e47 ("ipv4: ipmr: support multiple tables")
Fixes: d1db275dd3f6e4 ("ipv6: ip6mr: support multiple tables")
Reported-by: Bob Falken <NetFestivalHaveFun@gmx.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
xfs: Account log unmount transaction correctly

commit 3948659e30808fbaa7673bbe89de2ae9769e20a7 upstream.

There have been a few reports of this warning appearing recently:

XFS (dm-4): xlog_space_left: head behind tail
 tail_cycle = 129, tail_bytes = 20163072
 GH   cycle = 129, GH   bytes = 20162880

The common cause appears to be lots of freeze and unfreeze cycles,
and the output from the warnings indicates that we are leaking
around 8 bytes of log space per freeze/unfreeze cycle.

When we freeze the filesystem, we write an unmount record and that
uses xlog_write directly - a special type of transaction,
effectively. What it doesn't do, however, is correctly account for
the log space it uses. The unmount record writes an 8 byte structure
with a special magic number into the log, and the space this
consumes is not accounted for in the log ticket tracking the
operation. Hence we leak 8 bytes every unmount record that is
written.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
PCI: Enable ARI if dev and upstream bridge support it; disable otherwise

commit b0cc6020e1cc62f1253215f189611b34be4a83c7 upstream.

Currently, we enable ARI in a device's upstream bridge if the bridge and
the device support it.  But we never disable ARI, even if the device is
removed and replaced with a device that doesn't support ARI.

This means that if we hot-remove an ARI device and replace it with a
non-ARI multi-function device, we find only function 0 of the new device
because the upstream bridge still has ARI enabled, and next_ari_fn()
only returns function 0 for the new non-ARI device.

This patch disables ARI in the upstream bridge if the device doesn't
support ARI.  See the PCIe spec, r3.0, sec 6.13.

[bhelgaas: changelog, function comment]
[yijing: replace PCIe Cap accessor with legacy PCI accessor]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
mm/memory-failure.c: recheck PageHuge() after hugetlb page migrate successfully

commit a49ecbcd7b0d5a1cda7d60e03df402dd0ef76ac8 upstream.

After a successful hugetlb page migration by soft offline, the source
page will either be freed into hugepage_freelists or buddy(over-commit
page).  If page is in buddy, page_hstate(page) will be NULL.  It will
hit a NULL pointer dereference in dequeue_hwpoisoned_huge_page().

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
  IP: [<ffffffff81163761>] dequeue_hwpoisoned_huge_page+0x131/0x1d0
  PGD c23762067 PUD c24be2067 PMD 0
  Oops: 0000 [#1] SMP

So check PageHuge(page) after call migrate_pages() successfully.

Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Tested-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[wujg: backport to 3.4:
 - adjust context
 - s/num_poisoned_pages/mce_bad_pages/]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>