<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/include, branch v5.1.16</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.16</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.1.16'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2019-07-03T11:13:44Z</updated>
<entry>
<title>fanotify: update connector fsid cache on add mark</title>
<updated>2019-07-03T11:13:44Z</updated>
<author>
<name>Amir Goldstein</name>
<email>amir73il@gmail.com</email>
</author>
<published>2019-06-19T10:34:44Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b74063b5f16ab816dece79eec1830870d472aa43'/>
<id>urn:sha1:b74063b5f16ab816dece79eec1830870d472aa43</id>
<content type='text'>
commit c285a2f01d692ef48d7243cf1072897bbd237407 upstream.

When implementing connector fsid cache, we only initialized the cache
when the first mark added to object was added by FAN_REPORT_FID group.
We forgot to update conn-&gt;fsid when the second mark is added by
FAN_REPORT_FID group to an already attached connector without fsid
cache.

Reported-and-tested-by: syzbot+c277e8e2f46414645508@syzkaller.appspotmail.com
Fixes: 77115225acc6 ("fanotify: cache fsid in fsnotify_mark_connector")
Signed-off-by: Amir Goldstein &lt;amir73il@gmail.com&gt;
Signed-off-by: Jan Kara &lt;jack@suse.cz&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>futex: Update comments and docs about return values of arch futex code</title>
<updated>2019-07-03T11:13:44Z</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2019-04-10T10:51:54Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=41dd902f6ec7bfc2185e27c5c0f6ef7cb158bc1f'/>
<id>urn:sha1:41dd902f6ec7bfc2185e27c5c0f6ef7cb158bc1f</id>
<content type='text'>
commit 427503519739e779c0db8afe876c1b33f3ac60ae upstream.

The architecture implementations of 'arch_futex_atomic_op_inuser()' and
'futex_atomic_cmpxchg_inatomic()' are permitted to return only -EFAULT,
-EAGAIN or -ENOSYS in the case of failure.

Update the comments in the asm-generic/ implementation and also a stray
reference in the robust futex documentation.

Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>bpf: fix unconnected udp hooks</title>
<updated>2019-07-03T11:13:43Z</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2019-06-06T23:48:57Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=591c18e3aed16fde52cfdfc4af094b2cfd5dd0f2'/>
<id>urn:sha1:591c18e3aed16fde52cfdfc4af094b2cfd5dd0f2</id>
<content type='text'>
commit 983695fa676568fc0fe5ddd995c7267aabc24632 upstream.

Intention of cgroup bind/connect/sendmsg BPF hooks is to act transparently
to applications as also stated in original motivation in 7828f20e3779 ("Merge
branch 'bpf-cgroup-bind-connect'"). When recently integrating the latter
two hooks into Cilium to enable host based load-balancing with Kubernetes,
I ran into the issue that pods couldn't start up as DNS got broken. Kubernetes
typically sets up DNS as a service and is thus subject to load-balancing.

Upon further debugging, it turns out that the cgroupv2 sendmsg BPF hooks API
is currently insufficient and thus not usable as-is for standard applications
shipped with most distros. To break down the issue we ran into with a simple
example:

  # cat /etc/resolv.conf
  nameserver 147.75.207.207
  nameserver 147.75.207.208

For the purpose of a simple test, we set up above IPs as service IPs and
transparently redirect traffic to a different DNS backend server for that
node:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 =&gt; 8.8.8.8:53
  2    147.75.207.208:53   1 =&gt; 8.8.8.8:53

The attached BPF program is basically selecting one of the backends if the
service IP/port matches on the cgroup hook. DNS breaks here, because the
hooks are not transparent enough to applications which have built-in msg_name
address checks:

  # nslookup 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]
  ;; connection timed out; no servers could be reached

  # dig 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]

  ; &lt;&lt;&gt;&gt; DiG 9.11.3-1ubuntu1.7-Ubuntu &lt;&lt;&gt;&gt; 1.1.1.1
  ;; global options: +cmd
  ;; connection timed out; no servers could be reached

For comparison, if none of the service IPs is used, and we tell nslookup
to use 8.8.8.8 directly it works just fine, of course:

  # nslookup 1.1.1.1 8.8.8.8
  1.1.1.1.in-addr.arpa	name = one.one.one.one.

In order to fix this and thus act more transparent to the application,
this needs reverse translation on recvmsg() side. A minimal fix for this
API is to add similar recvmsg() hooks behind the BPF cgroups static key
such that the program can track state and replace the current sockaddr_in{,6}
with the original service IP. From BPF side, this basically tracks the
service tuple plus socket cookie in an LRU map where the reverse NAT can
then be retrieved via map value as one example. Side-note: the BPF cgroups
static key should be converted to a per-hook static key in future.

Same example after this fix:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 =&gt; 8.8.8.8:53
  2    147.75.207.208:53   1 =&gt; 8.8.8.8:53

Lookups work fine now:

  # nslookup 1.1.1.1
  1.1.1.1.in-addr.arpa    name = one.one.one.one.

  Authoritative answers can be found from:

  # dig 1.1.1.1

  ; &lt;&lt;&gt;&gt; DiG 9.11.3-1ubuntu1.7-Ubuntu &lt;&lt;&gt;&gt; 1.1.1.1
  ;; global options: +cmd
  ;; Got answer:
  ;; -&gt;&gt;HEADER&lt;&lt;- opcode: QUERY, status: NXDOMAIN, id: 51550
  ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

  ;; OPT PSEUDOSECTION:
  ; EDNS: version: 0, flags:; udp: 512
  ;; QUESTION SECTION:
  ;1.1.1.1.                       IN      A

  ;; AUTHORITY SECTION:
  .                       23426   IN      SOA     a.root-servers.net. nstld.verisign-grs.com. 2019052001 1800 900 604800 86400

  ;; Query time: 17 msec
  ;; SERVER: 147.75.207.207#53(147.75.207.207)
  ;; WHEN: Tue May 21 12:59:38 UTC 2019
  ;; MSG SIZE  rcvd: 111

And from an actual packet level it shows that we're using the back end
server when talking via 147.75.207.20{7,8} front end:

  # tcpdump -i any udp
  [...]
  12:59:52.698732 IP foo.42011 &gt; google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.698735 IP foo.42011 &gt; google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.701208 IP google-public-dns-a.google.com.domain &gt; foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  12:59:52.701208 IP google-public-dns-a.google.com.domain &gt; foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  [...]

In order to be flexible and to have same semantics as in sendmsg BPF
programs, we only allow return codes in [1,1] range. In the sendmsg case
the program is called if msg-&gt;msg_name is present which can be the case
in both, connected and unconnected UDP.

The former only relies on the sockaddr_in{,6} passed via connect(2) if
passed msg-&gt;msg_name was NULL. Therefore, on recvmsg side, we act in similar
way to call into the BPF program whenever a non-NULL msg-&gt;msg_name was
passed independent of sk-&gt;sk_state being TCP_ESTABLISHED or not. Note
that for TCP case, the msg-&gt;msg_name is ignored in the regular recvmsg
path and therefore not relevant.

For the case of ip{,v6}_recv_error() paths, picked up via MSG_ERRQUEUE,
the hook is not called. This is intentional as it aligns with the same
semantics as in case of TCP cgroup BPF hooks right now. This might be
better addressed in future through a different bpf_attach_type such
that this case can be distinguished from the regular recvmsg paths,
for example.

Fixes: 1cedee13d25a ("bpf: Hooks for sys_sendmsg")
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Andrey Ignatov &lt;rdna@fb.com&gt;
Acked-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Martynas Pumputis &lt;m@lambda.lt&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: simplify definition of BPF_FIB_LOOKUP related flags</title>
<updated>2019-07-03T11:13:42Z</updated>
<author>
<name>Martynas Pumputis</name>
<email>m@lambda.lt</email>
</author>
<published>2019-06-12T16:05:40Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=7108c83502e822e52052eea7d13f9d3d8bc8dea0'/>
<id>urn:sha1:7108c83502e822e52052eea7d13f9d3d8bc8dea0</id>
<content type='text'>
commit b1d6c15b9d824a58c5415673f374fac19e8eccdf upstream.

Previously, the BPF_FIB_LOOKUP_{DIRECT,OUTPUT} flags in the BPF UAPI
were defined with the help of BIT macro. This had the following issues:

- In order to use any of the flags, a user was required to depend
  on &lt;linux/bits.h&gt;.
- No other flag in bpf.h uses the macro, so it seems that an unwritten
  convention is to use (1 &lt;&lt; (nr)) to define BPF-related flags.

Fixes: 87f5fc7e48dd ("bpf: Provide helper to do forwarding lookups in kernel FIB table")
Signed-off-by: Martynas Pumputis &lt;m@lambda.lt&gt;
Acked-by: Andrii Nakryiko &lt;andriin@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>net/tls: fix page double free on TX cleanup</title>
<updated>2019-07-03T11:13:41Z</updated>
<author>
<name>Dirk van der Merwe</name>
<email>dirk.vandermerwe@netronome.com</email>
</author>
<published>2019-06-24T04:26:58Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0962d139f22a4e889e686b86806767b99eda8086'/>
<id>urn:sha1:0962d139f22a4e889e686b86806767b99eda8086</id>
<content type='text'>
[ Upstream commit 9354544cbccf68da1b047f8fb7b47630e3c8a59d ]

With commit 94850257cf0f ("tls: Fix tls_device handling of partial records")
a new path was introduced to cleanup partial records during sk_proto_close.
This path does not handle the SW KTLS tx_list cleanup.

This is unnecessary though since the free_resources calls for both
SW and offload paths will cleanup a partial record.

The visible effect is the following warning, but this bug also causes
a page double free.

    WARNING: CPU: 7 PID: 4000 at net/core/stream.c:206 sk_stream_kill_queues+0x103/0x110
    RIP: 0010:sk_stream_kill_queues+0x103/0x110
    RSP: 0018:ffffb6df87e07bd0 EFLAGS: 00010206
    RAX: 0000000000000000 RBX: ffff8c21db4971c0 RCX: 0000000000000007
    RDX: ffffffffffffffa0 RSI: 000000000000001d RDI: ffff8c21db497270
    RBP: ffff8c21db497270 R08: ffff8c29f4748600 R09: 000000010020001a
    R10: ffffb6df87e07aa0 R11: ffffffff9a445600 R12: 0000000000000007
    R13: 0000000000000000 R14: ffff8c21f03f2900 R15: ffff8c21f03b8df0
    Call Trace:
     inet_csk_destroy_sock+0x55/0x100
     tcp_close+0x25d/0x400
     ? tcp_check_oom+0x120/0x120
     tls_sk_proto_close+0x127/0x1c0
     inet_release+0x3c/0x60
     __sock_release+0x3d/0xb0
     sock_close+0x11/0x20
     __fput+0xd8/0x210
     task_work_run+0x84/0xa0
     do_exit+0x2dc/0xb90
     ? release_sock+0x43/0x90
     do_group_exit+0x3a/0xa0
     get_signal+0x295/0x720
     do_signal+0x36/0x610
     ? SYSC_recvfrom+0x11d/0x130
     exit_to_usermode_loop+0x69/0xb0
     do_syscall_64+0x173/0x180
     entry_SYSCALL_64_after_hwframe+0x3d/0xa2
    RIP: 0033:0x7fe9b9abc10d
    RSP: 002b:00007fe9b19a1d48 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
    RAX: fffffffffffffe00 RBX: 0000000000000006 RCX: 00007fe9b9abc10d
    RDX: 0000000000000002 RSI: 0000000000000080 RDI: 00007fe948003430
    RBP: 00007fe948003410 R08: 00007fe948003430 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000246 R12: 00005603739d9080
    R13: 00007fe9b9ab9f90 R14: 00007fe948003430 R15: 0000000000000000

Fixes: 94850257cf0f ("tls: Fix tls_device handling of partial records")
Signed-off-by: Dirk van der Merwe &lt;dirk.vandermerwe@netronome.com&gt;
Signed-off-by: Jakub Kicinski &lt;jakub.kicinski@netronome.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>
</entry>
<entry>
<title>mm: fix page cache convergence regression</title>
<updated>2019-07-03T11:13:39Z</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2019-05-24T14:12:46Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=994f9a520c1ba3a5d8d585888da4e27ff9abfeb0'/>
<id>urn:sha1:994f9a520c1ba3a5d8d585888da4e27ff9abfeb0</id>
<content type='text'>
commit 7b785645e8f13e17cbce492708cf6e7039d32e46 upstream.

Since a28334862993 ("page cache: Finish XArray conversion"), on most
major Linux distributions, the page cache doesn't correctly transition
when the hot data set is changing, and leaves the new pages thrashing
indefinitely instead of kicking out the cold ones.

On a freshly booted, freshly ssh'd into virtual machine with 1G RAM
running stock Arch Linux:

[root@ham ~]# ./reclaimtest.sh
+ dd of=workingset-a bs=1M count=0 seek=600
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ ./mincore workingset-a
153600/153600 workingset-a
+ dd of=workingset-b bs=1M count=0 seek=600
+ cat workingset-b
+ cat workingset-b
+ cat workingset-b
+ cat workingset-b
+ ./mincore workingset-a workingset-b
104029/153600 workingset-a
120086/153600 workingset-b
+ cat workingset-b
+ cat workingset-b
+ cat workingset-b
+ cat workingset-b
+ ./mincore workingset-a workingset-b
104029/153600 workingset-a
120268/153600 workingset-b

workingset-b is a 600M file on a 1G host that is otherwise entirely
idle. No matter how often it's being accessed, it won't get cached.

While investigating, I noticed that the non-resident information gets
aggressively reclaimed - /proc/vmstat::workingset_nodereclaim. This is
a problem because a workingset transition like this relies on the
non-resident information tracked in the page cache tree of evicted
file ranges: when the cache faults are refaults of recently evicted
cache, we challenge the existing active set, and that allows a new
workingset to establish itself.

Tracing the shrinker that maintains this memory revealed that all page
cache tree nodes were allocated to the root cgroup. This is a problem,
because 1) the shrinker sizes the amount of non-resident information
it keeps to the size of the cgroup's other memory and 2) on most major
Linux distributions, only kernel threads live in the root cgroup and
everything else gets put into services or session groups:

[root@ham ~]# cat /proc/self/cgroup
0::/user.slice/user-0.slice/session-c1.scope

As a result, we basically maintain no non-resident information for the
workloads running on the system, thus breaking the caching algorithm.

Looking through the code, I found the culprit in the above-mentioned
patch: when switching from the radix tree to xarray, it dropped the
__GFP_ACCOUNT flag from the tree node allocations - the flag that
makes sure the allocated memory gets charged to and tracked by the
cgroup of the calling process - in this case, the one doing the fault.

To fix this, allow xarray users to specify per-tree flag that makes
xarray allocate nodes using __GFP_ACCOUNT. Then restore the page cache
tree annotation to request such cgroup tracking for the cache nodes.

With this patch applied, the page cache correctly converges on new
workingsets again after just a few iterations:

[root@ham ~]# ./reclaimtest.sh
+ dd of=workingset-a bs=1M count=0 seek=600
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ cat workingset-a
+ ./mincore workingset-a
153600/153600 workingset-a
+ dd of=workingset-b bs=1M count=0 seek=600
+ cat workingset-b
+ ./mincore workingset-a workingset-b
124607/153600 workingset-a
87876/153600 workingset-b
+ cat workingset-b
+ ./mincore workingset-a workingset-b
81313/153600 workingset-a
133321/153600 workingset-b
+ cat workingset-b
+ ./mincore workingset-a workingset-b
63036/153600 workingset-a
153600/153600 workingset-b

Cc: stable@vger.kernel.org # 4.20+
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Reviewed-by: Shakeel Butt &lt;shakeelb@google.com&gt;
Signed-off-by: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>{nl,mac}80211: allow 4addr AP operation on crypto controlled devices</title>
<updated>2019-06-25T03:34:55Z</updated>
<author>
<name>Manikanta Pubbisetty</name>
<email>mpubbise@codeaurora.org</email>
</author>
<published>2019-05-08T09:25:33Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=0dd7d335f896e2f8d6b154fa2c07c6b9b5ccd00d'/>
<id>urn:sha1:0dd7d335f896e2f8d6b154fa2c07c6b9b5ccd00d</id>
<content type='text'>
commit 33d915d9e8ce811d8958915ccd18d71a66c7c495 upstream.

As per the current design, in the case of sw crypto controlled devices,
it is the device which advertises the support for AP/VLAN iftype based
on it's ability to tranmsit packets encrypted in software
(In VLAN functionality, group traffic generated for a specific
VLAN group is always encrypted in software). Commit db3bdcb9c3ff
("mac80211: allow AP_VLAN operation on crypto controlled devices")
has introduced this change.

Since 4addr AP operation also uses AP/VLAN iftype, this conditional
way of advertising AP/VLAN support has broken 4addr AP mode operation on
crypto controlled devices which do not support VLAN functionality.

In the case of ath10k driver, not all firmwares have support for VLAN
functionality but all can support 4addr AP operation. Because AP/VLAN
support is not advertised for these devices, 4addr AP operations are
also blocked.

Fix this by allowing 4addr operation on devices which do not support
AP/VLAN iftype but can support 4addr AP operation (decision is based on
the wiphy flag WIPHY_FLAG_4ADDR_AP).

Cc: stable@vger.kernel.org
Fixes: db3bdcb9c3ff ("mac80211: allow AP_VLAN operation on crypto controlled devices")
Signed-off-by: Manikanta Pubbisetty &lt;mpubbise@codeaurora.org&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>Bluetooth: Align minimum encryption key size for LE and BR/EDR connections</title>
<updated>2019-06-25T03:34:55Z</updated>
<author>
<name>Marcel Holtmann</name>
<email>marcel@holtmann.org</email>
</author>
<published>2019-04-24T20:19:17Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=640a7f2a52610efbfdffcb4a8b165da954e86a3c'/>
<id>urn:sha1:640a7f2a52610efbfdffcb4a8b165da954e86a3c</id>
<content type='text'>
commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.

The minimum encryption key size for LE connections is 56 bits and to
align LE with BR/EDR, enforce 56 bits of minimum encryption key size for
BR/EDR connections as well.

Signed-off-by: Marcel Holtmann &lt;marcel@holtmann.org&gt;
Signed-off-by: Johan Hedberg &lt;johan.hedberg@intel.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>mmc: core: Add sdio_retune_hold_now() and sdio_retune_release()</title>
<updated>2019-06-25T03:34:44Z</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2019-06-17T17:56:52Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=55dc448847c9edaf128234bc6f14ac9d16c11e6c'/>
<id>urn:sha1:55dc448847c9edaf128234bc6f14ac9d16c11e6c</id>
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commit b4c9f938d542d5f88c501744d2d12fad4fd2915f upstream.

We want SDIO drivers to be able to temporarily stop retuning when the
driver knows that the SDIO card is not in a state where retuning will
work (maybe because the card is asleep).  We'll move the relevant
functions to a place where drivers can call them.

Cc: stable@vger.kernel.org #v4.18+
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Acked-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Acked-by: Kalle Valo &lt;kvalo@codeaurora.org&gt;
Signed-off-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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</entry>
<entry>
<title>mmc: core: API to temporarily disable retuning for SDIO CRC errors</title>
<updated>2019-06-25T03:34:44Z</updated>
<author>
<name>Douglas Anderson</name>
<email>dianders@chromium.org</email>
</author>
<published>2019-06-17T17:56:50Z</published>
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commit 0a55f4ab9678413a01e740c86e9367ba0c612b36 upstream.

Normally when the MMC core sees an "-EILSEQ" error returned by a host
controller then it will trigger a retuning of the card.  This is
generally a good idea.

However, if a command is expected to sometimes cause transfer errors
then these transfer errors shouldn't cause a re-tuning.  This
re-tuning will be a needless waste of time.  One example case where a
transfer is expected to cause errors is when transitioning between
idle (sometimes referred to as "sleep" in Broadcom code) and active
state on certain Broadcom WiFi SDIO cards.  Specifically if the card
was already transitioning between states when the command was sent it
could cause an error on the SDIO bus.

Let's add an API that the SDIO function drivers can call that will
temporarily disable the auto-tuning functionality.  Then we can add a
call to this in the Broadcom WiFi driver and any other driver that
might have similar needs.

NOTE: this makes the assumption that the card is already tuned well
enough that it's OK to disable the auto-retuning during one of these
error-prone situations.  Presumably the driver code performing the
error-prone transfer knows how to recover / retry from errors.  ...and
after we can get back to a state where transfers are no longer
error-prone then we can enable the auto-retuning again.  If we truly
find ourselves in a case where the card needs to be retuned sometimes
to handle one of these error-prone transfers then we can always try a
few transfers first without auto-retuning and then re-try with
auto-retuning if the first few fail.

Without this change on rk3288-veyron-minnie I periodically see this in
the logs of a machine just sitting there idle:
  dwmmc_rockchip ff0d0000.dwmmc: Successfully tuned phase to XYZ

Cc: stable@vger.kernel.org #v4.18+
Signed-off-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Acked-by: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Acked-by: Kalle Valo &lt;kvalo@codeaurora.org&gt;
Signed-off-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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