<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git, branch v5.4.55</title>
<subtitle>Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git</subtitle>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/'/>
<entry>
<title>Linux 5.4.55</title>
<updated>2020-07-31T16:39:32+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2020-07-31T16:39:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=169b93899c7dfb93a2b57da8e3505da9b2afcf5c'/>
<id>169b93899c7dfb93a2b57da8e3505da9b2afcf5c</id>
<content type='text'>
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "dpaa_eth: fix usage as DSA master, try 3"</title>
<updated>2020-07-31T16:39:32+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2020-06-24T12:45:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=909dbf09cd018ab6ddd853f23061394d437777a6'/>
<id>909dbf09cd018ab6ddd853f23061394d437777a6</id>
<content type='text'>
This reverts commit 40a904b1c2e57b22dd002dfce73688871cb0bac8.

The patch is not wrong, but the Fixes: tag is. It should have been:

	Fixes: 060ad66f9795 ("dpaa_eth: change DMA device")

which means that it's fixing a commit which was introduced in:

git tag --contains 060ad66f97954
v5.5

which then means it should have not been backported to linux-5.4.y,
where things _were_ working and now they're not.

Reported-by: Joakim Tjernlund &lt;joakim.tjernlund@infinera.com&gt;
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This reverts commit 40a904b1c2e57b22dd002dfce73688871cb0bac8.

The patch is not wrong, but the Fixes: tag is. It should have been:

	Fixes: 060ad66f9795 ("dpaa_eth: change DMA device")

which means that it's fixing a commit which was introduced in:

git tag --contains 060ad66f97954
v5.5

which then means it should have not been backported to linux-5.4.y,
where things _were_ working and now they're not.

Reported-by: Joakim Tjernlund &lt;joakim.tjernlund@infinera.com&gt;
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM: wakeup: Show statistics for deleted wakeup sources again</title>
<updated>2020-07-31T16:39:32+00:00</updated>
<author>
<name>zhuguangqing</name>
<email>zhuguangqing@xiaomi.com</email>
</author>
<published>2019-12-09T09:35:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=4918285a6c7ddf0e3bbda163314030c3642dd08f'/>
<id>4918285a6c7ddf0e3bbda163314030c3642dd08f</id>
<content type='text'>
commit e976eb4b91e906f20ec25b20c152d53c472fc3fd upstream.

After commit 00ee22c28915 (PM / wakeup: Use seq_open() to show wakeup
stats), print_wakeup_source_stats(m, &amp;deleted_ws) is not called from
wakeup_sources_stats_seq_show() any more.

Because deleted_ws is one of the wakeup sources, it should be shown
too, so add it to the end of all other wakeup sources.

Signed-off-by: zhuguangqing &lt;zhuguangqing@xiaomi.com&gt;
[ rjw: Subject &amp; changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit e976eb4b91e906f20ec25b20c152d53c472fc3fd upstream.

After commit 00ee22c28915 (PM / wakeup: Use seq_open() to show wakeup
stats), print_wakeup_source_stats(m, &amp;deleted_ws) is not called from
wakeup_sources_stats_seq_show() any more.

Because deleted_ws is one of the wakeup sources, it should be shown
too, so add it to the end of all other wakeup sources.

Signed-off-by: zhuguangqing &lt;zhuguangqing@xiaomi.com&gt;
[ rjw: Subject &amp; changelog ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Florian Fainelli &lt;f.fainelli@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regmap: debugfs: check count when read regmap file</title>
<updated>2020-07-31T16:39:32+00:00</updated>
<author>
<name>Peng Fan</name>
<email>peng.fan@nxp.com</email>
</author>
<published>2020-03-13T01:58:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=59242fa1d2ba07a0748740aa63c64bfb6841639e'/>
<id>59242fa1d2ba07a0748740aa63c64bfb6841639e</id>
<content type='text'>
commit 74edd08a4fbf51d65fd8f4c7d8289cd0f392bd91 upstream.

When executing the following command, we met kernel dump.
dmesg -c &gt; /dev/null; cd /sys;
for i in `ls /sys/kernel/debug/regmap/* -d`; do
	echo "Checking regmap in $i";
	cat $i/registers;
done &amp;&amp; grep -ri "0x02d0" *;

It is because the count value is too big, and kmalloc fails. So add an
upper bound check to allow max size `PAGE_SIZE &lt;&lt; (MAX_ORDER - 1)`.

Signed-off-by: Peng Fan &lt;peng.fan@nxp.com&gt;
Link: https://lore.kernel.org/r/1584064687-12964-1-git-send-email-peng.fan@nxp.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 74edd08a4fbf51d65fd8f4c7d8289cd0f392bd91 upstream.

When executing the following command, we met kernel dump.
dmesg -c &gt; /dev/null; cd /sys;
for i in `ls /sys/kernel/debug/regmap/* -d`; do
	echo "Checking regmap in $i";
	cat $i/registers;
done &amp;&amp; grep -ri "0x02d0" *;

It is because the count value is too big, and kmalloc fails. So add an
upper bound check to allow max size `PAGE_SIZE &lt;&lt; (MAX_ORDER - 1)`.

Signed-off-by: Peng Fan &lt;peng.fan@nxp.com&gt;
Link: https://lore.kernel.org/r/1584064687-12964-1-git-send-email-peng.fan@nxp.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>udp: Improve load balancing for SO_REUSEPORT.</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.co.jp</email>
</author>
<published>2020-07-21T06:15:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=df89c1ee034ce11fa14dbbfe53d5b91ce70de5a6'/>
<id>df89c1ee034ce11fa14dbbfe53d5b91ce70de5a6</id>
<content type='text'>
[ Upstream commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace ]

Currently, SO_REUSEPORT does not work well if connected sockets are in a
UDP reuseport group.

Then reuseport_has_conns() returns true and the result of
reuseport_select_sock() is discarded. Also, unconnected sockets have the
same score, hence only does the first unconnected socket in udp_hslot
always receive all packets sent to unconnected sockets.

So, the result of reuseport_select_sock() should be used for load
balancing.

The noteworthy point is that the unconnected sockets placed after
connected sockets in sock_reuseport.socks will receive more packets than
others because of the algorithm in reuseport_select_sock().

    index | connected | reciprocal_scale | result
    ---------------------------------------------
    0     | no        | 20%              | 40%
    1     | no        | 20%              | 20%
    2     | yes       | 20%              | 0%
    3     | no        | 20%              | 40%
    4     | yes       | 20%              | 0%

If most of the sockets are connected, this can be a problem, but it still
works better than now.

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn &lt;willemb@google.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.co.jp&gt;
Acked-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace ]

Currently, SO_REUSEPORT does not work well if connected sockets are in a
UDP reuseport group.

Then reuseport_has_conns() returns true and the result of
reuseport_select_sock() is discarded. Also, unconnected sockets have the
same score, hence only does the first unconnected socket in udp_hslot
always receive all packets sent to unconnected sockets.

So, the result of reuseport_select_sock() should be used for load
balancing.

The noteworthy point is that the unconnected sockets placed after
connected sockets in sock_reuseport.socks will receive more packets than
others because of the algorithm in reuseport_select_sock().

    index | connected | reciprocal_scale | result
    ---------------------------------------------
    0     | no        | 20%              | 40%
    1     | no        | 20%              | 20%
    2     | yes       | 20%              | 0%
    3     | no        | 20%              | 40%
    4     | yes       | 20%              | 0%

If most of the sockets are connected, this can be a problem, but it still
works better than now.

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn &lt;willemb@google.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.co.jp&gt;
Acked-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>udp: Copy has_conns in reuseport_grow().</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Kuniyuki Iwashima</name>
<email>kuniyu@amazon.co.jp</email>
</author>
<published>2020-07-21T06:15:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=6735c126d27200db85c338410ffd34649dd572ff'/>
<id>6735c126d27200db85c338410ffd34649dd572ff</id>
<content type='text'>
[ Upstream commit f2b2c55e512879a05456eaf5de4d1ed2f7757509 ]

If an unconnected socket in a UDP reuseport group connect()s, has_conns is
set to 1. Then, when a packet is received, udp[46]_lib_lookup2() scans all
sockets in udp_hslot looking for the connected socket with the highest
score.

However, when the number of sockets bound to the port exceeds max_socks,
reuseport_grow() resets has_conns to 0. It can cause udp[46]_lib_lookup2()
to return without scanning all sockets, resulting in that packets sent to
connected sockets may be distributed to unconnected sockets.

Therefore, reuseport_grow() should copy has_conns.

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn &lt;willemb@google.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.co.jp&gt;
Acked-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit f2b2c55e512879a05456eaf5de4d1ed2f7757509 ]

If an unconnected socket in a UDP reuseport group connect()s, has_conns is
set to 1. Then, when a packet is received, udp[46]_lib_lookup2() scans all
sockets in udp_hslot looking for the connected socket with the highest
score.

However, when the number of sockets bound to the port exceeds max_socks,
reuseport_grow() resets has_conns to 0. It can cause udp[46]_lib_lookup2()
to return without scanning all sockets, resulting in that packets sent to
connected sockets may be distributed to unconnected sockets.

Therefore, reuseport_grow() should copy has_conns.

Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets")
CC: Willem de Bruijn &lt;willemb@google.com&gt;
Reviewed-by: Benjamin Herrenschmidt &lt;benh@amazon.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.co.jp&gt;
Acked-by: Willem de Bruijn &lt;willemb@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sctp: shrink stream outq when fails to do addstream reconf</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2020-07-22T15:52:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=86512c6938a9b56bc82bc24a5b61b527ee5fe6b7'/>
<id>86512c6938a9b56bc82bc24a5b61b527ee5fe6b7</id>
<content type='text'>
[ Upstream commit 3ecdda3e9ad837cf9cb41b6faa11b1af3a5abc0c ]

When adding a stream with stream reconf, the new stream firstly is in
CLOSED state but new out chunks can still be enqueued. Then once gets
the confirmation from the peer, the state will change to OPEN.

However, if the peer denies, it needs to roll back the stream. But when
doing that, it only sets the stream outcnt back, and the chunks already
in the new stream don't get purged. It caused these chunks can still be
dequeued in sctp_outq_dequeue_data().

As its stream is still in CLOSE, the chunk will be enqueued to the head
again by sctp_outq_head_data(). This chunk will never be sent out, and
the chunks after it can never be dequeued. The assoc will be 'hung' in
a dead loop of sending this chunk.

To fix it, this patch is to purge these chunks already in the new
stream by calling sctp_stream_shrink_out() when failing to do the
addstream reconf.

Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter")
Reported-by: Ying Xu &lt;yinxu@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 3ecdda3e9ad837cf9cb41b6faa11b1af3a5abc0c ]

When adding a stream with stream reconf, the new stream firstly is in
CLOSED state but new out chunks can still be enqueued. Then once gets
the confirmation from the peer, the state will change to OPEN.

However, if the peer denies, it needs to roll back the stream. But when
doing that, it only sets the stream outcnt back, and the chunks already
in the new stream don't get purged. It caused these chunks can still be
dequeued in sctp_outq_dequeue_data().

As its stream is still in CLOSE, the chunk will be enqueued to the head
again by sctp_outq_head_data(). This chunk will never be sent out, and
the chunks after it can never be dequeued. The assoc will be 'hung' in
a dead loop of sending this chunk.

To fix it, this patch is to purge these chunks already in the new
stream by calling sctp_stream_shrink_out() when failing to do the
addstream reconf.

Fixes: 11ae76e67a17 ("sctp: implement receiver-side procedures for the Reconf Response Parameter")
Reported-by: Ying Xu &lt;yinxu@redhat.com&gt;
Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sctp: shrink stream outq only when new outcnt &lt; old outcnt</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Xin Long</name>
<email>lucien.xin@gmail.com</email>
</author>
<published>2020-07-22T15:52:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=46e7c7efc30d97f47df4e814205e876a13f1999f'/>
<id>46e7c7efc30d97f47df4e814205e876a13f1999f</id>
<content type='text'>
[ Upstream commit 8f13399db22f909a35735bf8ae2f932e0c8f0e30 ]

It's not necessary to go list_for_each for outq-&gt;out_chunk_list
when new outcnt &gt;= old outcnt, as no chunk with higher sid than
new (outcnt - 1) exists in the outqueue.

While at it, also move the list_for_each code in a new function
sctp_stream_shrink_out(), which will be used in the next patch.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 8f13399db22f909a35735bf8ae2f932e0c8f0e30 ]

It's not necessary to go list_for_each for outq-&gt;out_chunk_list
when new outcnt &gt;= old outcnt, as no chunk with higher sid than
new (outcnt - 1) exists in the outqueue.

While at it, also move the list_for_each code in a new function
sctp_stream_shrink_out(), which will be used in the next patch.

Signed-off-by: Xin Long &lt;lucien.xin@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>AX.25: Prevent integer overflows in connect and sendmsg</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2020-07-23T14:49:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=bbf6af4a938a4b6f139440e6d8cd8cb76379962d'/>
<id>bbf6af4a938a4b6f139440e6d8cd8cb76379962d</id>
<content type='text'>
[ Upstream commit 17ad73e941b71f3bec7523ea4e9cbc3752461c2d ]

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb0621f0 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffad5c6 ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 17ad73e941b71f3bec7523ea4e9cbc3752461c2d ]

We recently added some bounds checking in ax25_connect() and
ax25_sendmsg() and we so we removed the AX25_MAX_DIGIS checks because
they were no longer required.

Unfortunately, I believe they are required to prevent integer overflows
so I have added them back.

Fixes: 8885bb0621f0 ("AX.25: Prevent out-of-bounds read in ax25_sendmsg()")
Fixes: 2f2a7ffad5c6 ("AX.25: Fix out-of-bounds read in ax25_connect()")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tcp: allow at most one TLP probe per flight</title>
<updated>2020-07-31T16:39:31+00:00</updated>
<author>
<name>Yuchung Cheng</name>
<email>ycheng@google.com</email>
</author>
<published>2020-07-23T19:00:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.exis.tech/linux.git/commit/?id=182ffc66456b20530def3b2d4f6b9a07545ac475'/>
<id>182ffc66456b20530def3b2d4f6b9a07545ac475</id>
<content type='text'>
[ Upstream commit 76be93fc0702322179bb0ea87295d820ee46ad14 ]

Previously TLP may send multiple probes of new data in one
flight. This happens when the sender is cwnd limited. After the
initial TLP containing new data is sent, the sender receives another
ACK that acks partial inflight.  It may re-arm another TLP timer
to send more, if no further ACK returns before the next TLP timeout
(PTO) expires. The sender may send in theory a large amount of TLP
until send queue is depleted. This only happens if the sender sees
such irregular uncommon ACK pattern. But it is generally undesirable
behavior during congestion especially.

The original TLP design restrict only one TLP probe per inflight as
published in "Reducing Web Latency: the Virtue of Gentle Aggression",
SIGCOMM 2013. This patch changes TLP to send at most one probe
per inflight.

Note that if the sender is app-limited, TLP retransmits old data
and did not have this issue.

Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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<pre>
[ Upstream commit 76be93fc0702322179bb0ea87295d820ee46ad14 ]

Previously TLP may send multiple probes of new data in one
flight. This happens when the sender is cwnd limited. After the
initial TLP containing new data is sent, the sender receives another
ACK that acks partial inflight.  It may re-arm another TLP timer
to send more, if no further ACK returns before the next TLP timeout
(PTO) expires. The sender may send in theory a large amount of TLP
until send queue is depleted. This only happens if the sender sees
such irregular uncommon ACK pattern. But it is generally undesirable
behavior during congestion especially.

The original TLP design restrict only one TLP probe per inflight as
published in "Reducing Web Latency: the Virtue of Gentle Aggression",
SIGCOMM 2013. This patch changes TLP to send at most one probe
per inflight.

Note that if the sender is app-limited, TLP retransmits old data
and did not have this issue.

Signed-off-by: Yuchung Cheng &lt;ycheng@google.com&gt;
Signed-off-by: Neal Cardwell &lt;ncardwell@google.com&gt;
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
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