<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include, branch v4.19.291</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.19.291</id>
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<updated>2023-08-11T09:45:40Z</updated>
<entry>
<title>PM / wakeirq: support enabling wake-up irq after runtime_suspend called</title>
<updated>2023-08-11T09:45:40Z</updated>
<author>
<name>Chunfeng Yun</name>
<email>chunfeng.yun@mediatek.com</email>
</author>
<published>2021-10-25T07:01:53Z</published>
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<id>urn:sha1:03f408a108169861180e66d0278f1a3083cbf068</id>
<content type='text'>
[ Upstream commit 259714100d98b50bf04d36a21bf50ca8b829fc11 ]

When the dedicated wake IRQ is level trigger, and it uses the
device's low-power status as the wakeup source, that means if the
device is not in low-power state, the wake IRQ will be triggered
if enabled; For this case, need enable the wake IRQ after running
the device's -&gt;runtime_suspend() which make it enter low-power state.

e.g.
Assume the wake IRQ is a low level trigger type, and the wakeup
signal comes from the low-power status of the device.
The wakeup signal is low level at running time (0), and becomes
high level when the device enters low-power state (runtime_suspend
(1) is called), a wakeup event at (2) make the device exit low-power
state, then the wakeup signal also becomes low level.

                ------------------
               |           ^     ^|
----------------           |     | --------------
 |&lt;---(0)---&gt;|&lt;--(1)--|   (3)   (2)    (4)

if enable the wake IRQ before running runtime_suspend during (0),
a wake IRQ will arise, it causes resume immediately;
it works if enable wake IRQ ( e.g. at (3) or (4)) after running
-&gt;runtime_suspend().

This patch introduces a new status WAKE_IRQ_DEDICATED_REVERSE to
optionally support enabling wake IRQ after running -&gt;runtime_suspend().

Suggested-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Chunfeng Yun &lt;chunfeng.yun@mediatek.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Stable-dep-of: 8527beb12087 ("PM: sleep: wakeirq: fix wake irq arming")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>word-at-a-time: use the same return type for has_zero regardless of endianness</title>
<updated>2023-08-11T09:45:36Z</updated>
<author>
<name>ndesaulniers@google.com</name>
<email>ndesaulniers@google.com</email>
</author>
<published>2023-08-01T22:22:17Z</published>
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<id>urn:sha1:b3fa40b14e89afa48fad2953694c8947247c85aa</id>
<content type='text'>
[ Upstream commit 79e8328e5acbe691bbde029a52c89d70dcbc22f3 ]

Compiling big-endian targets with Clang produces the diagnostic:

  fs/namei.c:2173:13: warning: use of bitwise '|' with boolean operands [-Wbitwise-instead-of-logical]
	} while (!(has_zero(a, &amp;adata, &amp;constants) | has_zero(b, &amp;bdata, &amp;constants)));
	          ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                               ||
  fs/namei.c:2173:13: note: cast one or both operands to int to silence this warning

It appears that when has_zero was introduced, two definitions were
produced with different signatures (in particular different return
types).

Looking at the usage in hash_name() in fs/namei.c, I suspect that
has_zero() is meant to be invoked twice per while loop iteration; using
logical-or would not update `bdata` when `a` did not have zeros.  So I
think it's preferred to always return an unsigned long rather than a
bool than update the while loop in hash_name() to use a logical-or
rather than bitwise-or.

[ Also changed powerpc version to do the same  - Linus ]

Link: https://github.com/ClangBuiltLinux/linux/issues/1832
Link: https://lore.kernel.org/lkml/20230801-bitwise-v1-1-799bec468dc4@google.com/
Fixes: 36126f8f2ed8 ("word-at-a-time: make the interfaces truly generic")
Debugged-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>block: Fix a source code comment in include/uapi/linux/blkzoned.h</title>
<updated>2023-08-11T09:45:32Z</updated>
<author>
<name>Bart Van Assche</name>
<email>bvanassche@acm.org</email>
</author>
<published>2023-07-06T20:14:12Z</published>
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<id>urn:sha1:ab197ad7995e67bacf486733656d7f7433fa1791</id>
<content type='text'>
[ Upstream commit e0933b526fbfd937c4a8f4e35fcdd49f0e22d411 ]

Fix the symbolic names for zone conditions in the blkzoned.h header
file.

Cc: Hannes Reinecke &lt;hare@suse.de&gt;
Cc: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Fixes: 6a0cb1bc106f ("block: Implement support for zoned block devices")
Signed-off-by: Bart Van Assche &lt;bvanassche@acm.org&gt;
Reviewed-by: Damien Le Moal &lt;dlemoal@kernel.org&gt;
Link: https://lore.kernel.org/r/20230706201422.3987341-1-bvanassche@acm.org
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tcp: Reduce chance of collisions in inet6_hashfn().</title>
<updated>2023-08-11T09:45:31Z</updated>
<author>
<name>Stewart Smith</name>
<email>trawets@amazon.com</email>
</author>
<published>2023-07-21T22:24:10Z</published>
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<id>urn:sha1:8fa0dea2fc96f192d81a12434e48deda2e556320</id>
<content type='text'>
[ Upstream commit d11b0df7ddf1831f3e170972f43186dad520bfcc ]

For both IPv4 and IPv6 incoming TCP connections are tracked in a hash
table with a hash over the source &amp; destination addresses and ports.
However, the IPv6 hash is insufficient and can lead to a high rate of
collisions.

The IPv6 hash used an XOR to fit everything into the 96 bits for the
fast jenkins hash, meaning it is possible for an external entity to
ensure the hash collides, thus falling back to a linear search in the
bucket, which is slow.

We take the approach of hash the full length of IPv6 address in
__ipv6_addr_jhash() so that all users can benefit from a more secure
version.

While this may look like it adds overhead, the reality of modern CPUs
means that this is unmeasurable in real world scenarios.

In simulating with llvm-mca, the increase in cycles for the hashing
code was ~16 cycles on Skylake (from a base of ~155), and an extra ~9
on Nehalem (base of ~173).

In commit dd6d2910c5e0 ("netfilter: conntrack: switch to siphash")
netfilter switched from a jenkins hash to a siphash, but even the faster
hsiphash is a more significant overhead (~20-30%) in some preliminary
testing.  So, in this patch, we keep to the more conservative approach to
ensure we don't add much overhead per SYN.

In testing, this results in a consistently even spread across the
connection buckets.  In both testing and real-world scenarios, we have
not found any measurable performance impact.

Fixes: 08dcdbf6a7b9 ("ipv6: use a stronger hash for tcp")
Signed-off-by: Stewart Smith &lt;trawets@amazon.com&gt;
Signed-off-by: Samuel Mendoza-Jonas &lt;samjonas@amazon.com&gt;
Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Kuniyuki Iwashima &lt;kuniyu@amazon.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20230721222410.17914-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tcp: annotate data-races around fastopenq.max_qlen</title>
<updated>2023-08-11T09:45:27Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-07-19T21:28:57Z</published>
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<id>urn:sha1:cc4122c81d211307c7cd2ddf7455ee171d867983</id>
<content type='text'>
[ Upstream commit 70f360dd7042cb843635ece9d28335a4addff9eb ]

This field can be read locklessly.

Fixes: 1536e2857bd3 ("tcp: Add a TCP_FASTOPEN socket option to get a max backlog on its listner")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20230719212857.3943972-12-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tcp: annotate data-races around tp-&gt;notsent_lowat</title>
<updated>2023-08-11T09:45:27Z</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2023-07-19T21:28:55Z</published>
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<id>urn:sha1:73e2b8a15ea42ccb2d4bcd26e55d4092a1a8e4e5</id>
<content type='text'>
[ Upstream commit 1aeb87bc1440c5447a7fa2d6e3c2cca52cbd206b ]

tp-&gt;notsent_lowat can be read locklessly from do_tcp_getsockopt()
and tcp_poll().

Fixes: c9bee3b7fdec ("tcp: TCP_NOTSENT_LOWAT socket option")
Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20230719212857.3943972-10-edumazet@google.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>net: Replace the limit of TCP_LINGER2 with TCP_FIN_TIMEOUT_MAX</title>
<updated>2023-08-11T09:45:27Z</updated>
<author>
<name>Cambda Zhu</name>
<email>cambda@linux.alibaba.com</email>
</author>
<published>2020-04-24T08:06:16Z</published>
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<id>urn:sha1:457202c473b933dfcee9ea8f45fff18e9f8d448f</id>
<content type='text'>
[ Upstream commit f0628c524fd188c3f9418e12478dfdfadacba815 ]

This patch changes the behavior of TCP_LINGER2 about its limit. The
sysctl_tcp_fin_timeout used to be the limit of TCP_LINGER2 but now it's
only the default value. A new macro named TCP_FIN_TIMEOUT_MAX is added
as the limit of TCP_LINGER2, which is 2 minutes.

Since TCP_LINGER2 used sysctl_tcp_fin_timeout as the default value
and the limit in the past, the system administrator cannot set the
default value for most of sockets and let some sockets have a greater
timeout. It might be a mistake that let the sysctl to be the limit of
the TCP_LINGER2. Maybe we can add a new sysctl to set the max of
TCP_LINGER2, but FIN-WAIT-2 timeout is usually no need to be too long
and 2 minutes are legal considering TCP specs.

Changes in v3:
- Remove the new socket option and change the TCP_LINGER2 behavior so
  that the timeout can be set to value between sysctl_tcp_fin_timeout
  and 2 minutes.

Changes in v2:
- Add int overflow check for the new socket option.

Changes in v1:
- Add a new socket option to set timeout greater than
  sysctl_tcp_fin_timeout.

Signed-off-by: Cambda Zhu &lt;cambda@linux.alibaba.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 9df5335ca974 ("tcp: annotate data-races around tp-&gt;linger2")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>posix-timers: Ensure timer ID search-loop limit is valid</title>
<updated>2023-08-11T09:45:25Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2023-06-01T18:58:47Z</published>
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<id>urn:sha1:9ea26a8494a0a9337e7415eafd6f3ed940327dc5</id>
<content type='text'>
[ Upstream commit 8ce8849dd1e78dadcee0ec9acbd259d239b7069f ]

posix_timer_add() tries to allocate a posix timer ID by starting from the
cached ID which was stored by the last successful allocation.

This is done in a loop searching the ID space for a free slot one by
one. The loop has to terminate when the search wrapped around to the
starting point.

But that's racy vs. establishing the starting point. That is read out
lockless, which leads to the following problem:

CPU0	  	      	     	   CPU1
posix_timer_add()
  start = sig-&gt;posix_timer_id;
  lock(hash_lock);
  ...				   posix_timer_add()
  if (++sig-&gt;posix_timer_id &lt; 0)
      			             start = sig-&gt;posix_timer_id;
     sig-&gt;posix_timer_id = 0;

So CPU1 can observe a negative start value, i.e. -1, and the loop break
never happens because the condition can never be true:

  if (sig-&gt;posix_timer_id == start)
     break;

While this is unlikely to ever turn into an endless loop as the ID space is
huge (INT_MAX), the racy read of the start value caught the attention of
KCSAN and Dmitry unearthed that incorrectness.

Rewrite it so that all id operations are under the hash lock.

Reported-by: syzbot+5c54bd3eb218bb595aa9@syzkaller.appspotmail.com
Reported-by: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Link: https://lore.kernel.org/r/87bkhzdn6g.ffs@tglx
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>Revert "8250: add support for ASIX devices with a FIFO bug"</title>
<updated>2023-08-11T09:45:22Z</updated>
<author>
<name>Jiaqing Zhao</name>
<email>jiaqing.zhao@linux.intel.com</email>
</author>
<published>2023-06-19T15:57:44Z</published>
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<id>urn:sha1:59ca634b88bd99b3fffb5c4b6ed24c66874fa310</id>
<content type='text'>
commit a82d62f708545d22859584e0e0620da8e3759bbc upstream.

This reverts commit eb26dfe8aa7eeb5a5aa0b7574550125f8aa4c3b3.

Commit eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO
bug") merged on Jul 13, 2012 adds a quirk for PCI_VENDOR_ID_ASIX
(0x9710). But that ID is the same as PCI_VENDOR_ID_NETMOS defined in
1f8b061050c7 ("[PATCH] Netmos parallel/serial/combo support") merged
on Mar 28, 2005. In pci_serial_quirks array, the NetMos entry always
takes precedence over the ASIX entry even since it was initially
merged, code in that commit is always unreachable.

In my tests, adding the FIFO workaround to pci_netmos_init() makes no
difference, and the vendor driver also does not have such workaround.
Given that the code was never used for over a decade, it's safe to
revert it.

Also, the real PCI_VENDOR_ID_ASIX should be 0x125b, which is used on
their newer AX99100 PCIe serial controllers released on 2016. The FIFO
workaround should not be intended for these newer controllers, and it
was never implemented in vendor driver.

Fixes: eb26dfe8aa7e ("8250: add support for ASIX devices with a FIFO bug")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Jiaqing Zhao &lt;jiaqing.zhao@linux.intel.com&gt;
Reviewed-by: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Link: https://lore.kernel.org/r/20230619155743.827859-1-jiaqing.zhao@linux.intel.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>net/sched: make psched_mtu() RTNL-less safe</title>
<updated>2023-08-11T09:45:19Z</updated>
<author>
<name>Pedro Tammela</name>
<email>pctammela@mojatatu.com</email>
</author>
<published>2023-07-11T02:16:34Z</published>
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<id>urn:sha1:fbbf4dfe5d6a0fcb7a9a0aa2371e083767b060d5</id>
<content type='text'>
[ Upstream commit 150e33e62c1fa4af5aaab02776b6c3812711d478 ]

Eric Dumazet says[1]:
-------
Speaking of psched_mtu(), I see that net/sched/sch_pie.c is using it
without holding RTNL, so dev-&gt;mtu can be changed underneath.
KCSAN could issue a warning.
-------

Annotate dev-&gt;mtu with READ_ONCE() so KCSAN don't issue a warning.

[1] https://lore.kernel.org/all/CANn89iJoJO5VtaJ-2=_d2aOQhb0Xw8iBT_Cxqp2HyuS-zj6azw@mail.gmail.com/

v1 -&gt; v2: Fix commit message

Fixes: d4b36210c2e6 ("net: pkt_sched: PIE AQM scheme")
Suggested-by: Eric Dumazet &lt;edumazet@google.com&gt;
Signed-off-by: Pedro Tammela &lt;pctammela@mojatatu.com&gt;
Reviewed-by: Simon Horman &lt;simon.horman@corigine.com&gt;
Link: https://lore.kernel.org/r/20230711021634.561598-1-pctammela@mojatatu.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
