<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/media, branch v4.7</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>media: fix airspy usb probe error path</title>
<updated>2016-07-15T21:15:40+00:00</updated>
<author>
<name>James Patrick-Evans</name>
<email>james@jmp-e.com</email>
</author>
<published>2016-07-15T15:40:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=aa93d1fee85c890a34f2510a310e55ee76a27848'/>
<id>aa93d1fee85c890a34f2510a310e55ee76a27848</id>
<content type='text'>
Fix a memory leak on probe error of the airspy usb device driver.

The problem is triggered when more than 64 usb devices register with
v4l2 of type VFL_TYPE_SDR or VFL_TYPE_SUBDEV.

The memory leak is caused by the probe function of the airspy driver
mishandeling errors and not freeing the corresponding control structures
when an error occours registering the device to v4l2 core.

A badusb device can emulate 64 of these devices, and then through
continual emulated connect/disconnect of the 65th device, cause the
kernel to run out of RAM and crash the kernel, thus causing a local DOS
vulnerability.

Fixes CVE-2016-5400

Signed-off-by: James Patrick-Evans &lt;james@jmp-e.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix a memory leak on probe error of the airspy usb device driver.

The problem is triggered when more than 64 usb devices register with
v4l2 of type VFL_TYPE_SDR or VFL_TYPE_SUBDEV.

The memory leak is caused by the probe function of the airspy driver
mishandeling errors and not freeing the corresponding control structures
when an error occours registering the device to v4l2 core.

A badusb device can emulate 64 of these devices, and then through
continual emulated connect/disconnect of the 65th device, cause the
kernel to run out of RAM and crash the kernel, thus causing a local DOS
vulnerability.

Fixes CVE-2016-5400

Signed-off-by: James Patrick-Evans &lt;james@jmp-e.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'media/v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media</title>
<updated>2016-07-13T10:51:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-07-13T10:51:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=cf875cc1dc6cb43cec754e92092579a51d2ad095'/>
<id>cf875cc1dc6cb43cec754e92092579a51d2ad095</id>
<content type='text'>
Pull media fixes from Mauro Carvalho Chehab:
 "Two regression fixes:

  - a regression when handling VIDIOC_CROPCAP at the media core;

  - a regression at adv7604 that was ignoring pad number in subdev ops"

* tag 'media/v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] adv7604: Don't ignore pad number in subdev DV timings pad operations
  [media] v4l2-ioctl: fix stupid mistake in cropcap condition
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull media fixes from Mauro Carvalho Chehab:
 "Two regression fixes:

  - a regression when handling VIDIOC_CROPCAP at the media core;

  - a regression at adv7604 that was ignoring pad number in subdev ops"

* tag 'media/v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
  [media] adv7604: Don't ignore pad number in subdev DV timings pad operations
  [media] v4l2-ioctl: fix stupid mistake in cropcap condition
</pre>
</div>
</content>
</entry>
<entry>
<title>Update my main e-mails at the Kernel tree</title>
<updated>2016-06-16T01:35:37+00:00</updated>
<author>
<name>Mauro Carvalho Chehab</name>
<email>mchehab@s-opensource.com</email>
</author>
<published>2016-06-14T18:17:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5dc8a864be0820677e7fce85d2832d4387c7bb88'/>
<id>5dc8a864be0820677e7fce85d2832d4387c7bb88</id>
<content type='text'>
For the third time in three years, I'm changing my e-mail at Samsung.
That's bad, as it may stop communications with me for a while.  So, this
time, I'll also add the mchehab@kernel.org e-mail, as it remains stable
since ever.

Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@s-opensource.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For the third time in three years, I'm changing my e-mail at Samsung.
That's bad, as it may stop communications with me for a while.  So, this
time, I'll also add the mchehab@kernel.org e-mail, as it remains stable
since ever.

Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@s-opensource.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>uvc_v4l2: Simplify compat ioctl implementation</title>
<updated>2016-06-10T22:11:15+00:00</updated>
<author>
<name>Andy Lutomirski</name>
<email>luto@kernel.org</email>
</author>
<published>2016-05-12T00:41:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f89dec72e98b34b3be66bb1ef1be62974c0f8483'/>
<id>f89dec72e98b34b3be66bb1ef1be62974c0f8483</id>
<content type='text'>
The uvc compat ioctl implementation seems to have copied user data
for no good reason.  Remove a bunch of copies.

Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The uvc compat ioctl implementation seems to have copied user data
for no good reason.  Remove a bunch of copies.

Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>uvc: Forward compat ioctls to their handlers directly</title>
<updated>2016-06-10T22:11:14+00:00</updated>
<author>
<name>Andy Lutomirski</name>
<email>luto@kernel.org</email>
</author>
<published>2016-05-24T22:13:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a44323e2a8f342848bb77e8e04fcd85fcb91b3b4'/>
<id>a44323e2a8f342848bb77e8e04fcd85fcb91b3b4</id>
<content type='text'>
The current code goes through a lot of indirection just to call a
known handler.  Simplify it: just call the handlers directly.

Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The current code goes through a lot of indirection just to call a
known handler.  Simplify it: just call the handlers directly.

Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[media] adv7604: Don't ignore pad number in subdev DV timings pad operations</title>
<updated>2016-06-07T18:33:54+00:00</updated>
<author>
<name>Laurent Pinchart</name>
<email>laurent.pinchart@ideasonboard.com</email>
</author>
<published>2016-05-24T12:09:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6519c3d7b8621c9f4333c98ed4b703029b51ba79'/>
<id>6519c3d7b8621c9f4333c98ed4b703029b51ba79</id>
<content type='text'>
The dv_timings_cap() and enum_dv_timings() pad operations take a pad
number as an input argument and return the DV timings capabilities and
list of supported DV timings for that pad.

Commit bd3e275f3ec0 ("[media] media: i2c: adv7604: Use v4l2-dv-timings
helpers") broke this as it started ignoring the pad number, always
returning the information associated with the currently selected input.
Fix it.

Fixes: bd3e275f3ec0 ("[media] media: i2c: adv7604: Use v4l2-dv-timings helpers")

Signed-off-by: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Signed-off-by: Hans Verkuil &lt;hans.verkuil@cisco.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;      # for v4.6
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@osg.samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The dv_timings_cap() and enum_dv_timings() pad operations take a pad
number as an input argument and return the DV timings capabilities and
list of supported DV timings for that pad.

Commit bd3e275f3ec0 ("[media] media: i2c: adv7604: Use v4l2-dv-timings
helpers") broke this as it started ignoring the pad number, always
returning the information associated with the currently selected input.
Fix it.

Fixes: bd3e275f3ec0 ("[media] media: i2c: adv7604: Use v4l2-dv-timings helpers")

Signed-off-by: Laurent Pinchart &lt;laurent.pinchart@ideasonboard.com&gt;
Signed-off-by: Hans Verkuil &lt;hans.verkuil@cisco.com&gt;
Cc: &lt;stable@vger.kernel.org&gt;      # for v4.6
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@osg.samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>[media] v4l2-ioctl: fix stupid mistake in cropcap condition</title>
<updated>2016-06-07T17:39:20+00:00</updated>
<author>
<name>Hans Verkuil</name>
<email>hverkuil@xs4all.nl</email>
</author>
<published>2016-05-23T11:45:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1ca830b110cd9d067327571f1136fdbf1ef2b4d3'/>
<id>1ca830b110cd9d067327571f1136fdbf1ef2b4d3</id>
<content type='text'>
Fix duplicate tests in condition. The second test for vidioc_cropcap
should have tested for vidioc_g_selection instead.

Signed-off-by: Hans Verkuil &lt;hans.verkuil@cisco.com&gt;
Reported-by: David Binderman &lt;linuxdev.baldrick@gmail.com&gt;
Acked-by: Sakari Ailus &lt;sakari.ailus@linux.intel.com&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@osg.samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Fix duplicate tests in condition. The second test for vidioc_cropcap
should have tested for vidioc_g_selection instead.

Signed-off-by: Hans Verkuil &lt;hans.verkuil@cisco.com&gt;
Reported-by: David Binderman &lt;linuxdev.baldrick@gmail.com&gt;
Acked-by: Sakari Ailus &lt;sakari.ailus@linux.intel.com&gt;
Signed-off-by: Mauro Carvalho Chehab &lt;mchehab@osg.samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'hash' of git://ftp.sciencehorizons.net/linux</title>
<updated>2016-05-28T23:15:25+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-05-28T23:15:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7e0fb73c52c4037b4d5ef9ff56c7296a3151bd92'/>
<id>7e0fb73c52c4037b4d5ef9ff56c7296a3151bd92</id>
<content type='text'>
Pull string hash improvements from George Spelvin:
 "This series does several related things:

   - Makes the dcache hash (fs/namei.c) useful for general kernel use.

     (Thanks to Bruce for noticing the zero-length corner case)

   - Converts the string hashes in &lt;linux/sunrpc/svcauth.h&gt; to use the
     above.

   - Avoids 64-bit multiplies in hash_64() on 32-bit platforms.  Two
     32-bit multiplies will do well enough.

   - Rids the world of the bad hash multipliers in hash_32.

     This finishes the job started in commit 689de1d6ca95 ("Minimal
     fix-up of bad hashing behavior of hash_64()")

     The vast majority of Linux architectures have hardware support for
     32x32-bit multiply and so derive no benefit from "simplified"
     multipliers.

     The few processors that do not (68000, h8/300 and some models of
     Microblaze) have arch-specific implementations added.  Those
     patches are last in the series.

   - Overhauls the dcache hash mixing.

     The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if
     CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion.
     Replaced with a much more careful design that's simultaneously
     faster and better.  (My own invention, as there was noting suitable
     in the literature I could find.  Comments welcome!)

   - Modify the hash_name() loop to skip the initial HASH_MIX().  This
     would let us salt the hash if we ever wanted to.

   - Sort out partial_name_hash().

     The hash function is declared as using a long state, even though
     it's truncated to 32 bits at the end and the extra internal state
     contributes nothing to the result.  And some callers do odd things:

      - fs/hfs/string.c only allocates 32 bits of state
      - fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes

   - Modify bytemask_from_count to handle inputs of 1..sizeof(long)
     rather than 0..sizeof(long)-1.  This would simplify users other
     than full_name_hash"

  Special thanks to Bruce Fields for testing and finding bugs in v1.  (I
  learned some humbling lessons about "obviously correct" code.)

  On the arch-specific front, the m68k assembly has been tested in a
  standalone test harness, I've been in contact with the Microblaze
  maintainers who mostly don't care, as the hardware multiplier is never
  omitted in real-world applications, and I haven't heard anything from
  the H8/300 world"

* 'hash' of git://ftp.sciencehorizons.net/linux:
  h8300: Add &lt;asm/hash.h&gt;
  microblaze: Add &lt;asm/hash.h&gt;
  m68k: Add &lt;asm/hash.h&gt;
  &lt;linux/hash.h&gt;: Add support for architecture-specific functions
  fs/namei.c: Improve dcache hash function
  Eliminate bad hash multipliers from hash_32() and  hash_64()
  Change hash_64() return value to 32 bits
  &lt;linux/sunrpc/svcauth.h&gt;: Define hash_str() in terms of hashlen_string()
  fs/namei.c: Add hashlen_string() function
  Pull out string hash to &lt;linux/stringhash.h&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull string hash improvements from George Spelvin:
 "This series does several related things:

   - Makes the dcache hash (fs/namei.c) useful for general kernel use.

     (Thanks to Bruce for noticing the zero-length corner case)

   - Converts the string hashes in &lt;linux/sunrpc/svcauth.h&gt; to use the
     above.

   - Avoids 64-bit multiplies in hash_64() on 32-bit platforms.  Two
     32-bit multiplies will do well enough.

   - Rids the world of the bad hash multipliers in hash_32.

     This finishes the job started in commit 689de1d6ca95 ("Minimal
     fix-up of bad hashing behavior of hash_64()")

     The vast majority of Linux architectures have hardware support for
     32x32-bit multiply and so derive no benefit from "simplified"
     multipliers.

     The few processors that do not (68000, h8/300 and some models of
     Microblaze) have arch-specific implementations added.  Those
     patches are last in the series.

   - Overhauls the dcache hash mixing.

     The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if
     CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion.
     Replaced with a much more careful design that's simultaneously
     faster and better.  (My own invention, as there was noting suitable
     in the literature I could find.  Comments welcome!)

   - Modify the hash_name() loop to skip the initial HASH_MIX().  This
     would let us salt the hash if we ever wanted to.

   - Sort out partial_name_hash().

     The hash function is declared as using a long state, even though
     it's truncated to 32 bits at the end and the extra internal state
     contributes nothing to the result.  And some callers do odd things:

      - fs/hfs/string.c only allocates 32 bits of state
      - fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes

   - Modify bytemask_from_count to handle inputs of 1..sizeof(long)
     rather than 0..sizeof(long)-1.  This would simplify users other
     than full_name_hash"

  Special thanks to Bruce Fields for testing and finding bugs in v1.  (I
  learned some humbling lessons about "obviously correct" code.)

  On the arch-specific front, the m68k assembly has been tested in a
  standalone test harness, I've been in contact with the Microblaze
  maintainers who mostly don't care, as the hardware multiplier is never
  omitted in real-world applications, and I haven't heard anything from
  the H8/300 world"

* 'hash' of git://ftp.sciencehorizons.net/linux:
  h8300: Add &lt;asm/hash.h&gt;
  microblaze: Add &lt;asm/hash.h&gt;
  m68k: Add &lt;asm/hash.h&gt;
  &lt;linux/hash.h&gt;: Add support for architecture-specific functions
  fs/namei.c: Improve dcache hash function
  Eliminate bad hash multipliers from hash_32() and  hash_64()
  Change hash_64() return value to 32 bits
  &lt;linux/sunrpc/svcauth.h&gt;: Define hash_str() in terms of hashlen_string()
  fs/namei.c: Add hashlen_string() function
  Pull out string hash to &lt;linux/stringhash.h&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Eliminate bad hash multipliers from hash_32() and  hash_64()</title>
<updated>2016-05-28T19:42:51+00:00</updated>
<author>
<name>George Spelvin</name>
<email>linux@sciencehorizons.net</email>
</author>
<published>2016-05-27T03:00:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ef703f49a6c5b909a85149bb6625c4ed0d697186'/>
<id>ef703f49a6c5b909a85149bb6625c4ed0d697186</id>
<content type='text'>
The "simplified" prime multipliers made very bad hash functions, so get rid
of them.  This completes the work of 689de1d6ca.

To avoid the inefficiency which was the motivation for the "simplified"
multipliers, hash_64() on 32-bit systems is changed to use a different
algorithm.  It makes two calls to hash_32() instead.

drivers/media/usb/dvb-usb-v2/af9015.c uses the old GOLDEN_RATIO_PRIME_32
for some horrible reason, so it inherits a copy of the old definition.

Signed-off-by: George Spelvin &lt;linux@sciencehorizons.net&gt;
Cc: Antti Palosaari &lt;crope@iki.fi&gt;
Cc: Mauro Carvalho Chehab &lt;m.chehab@samsung.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The "simplified" prime multipliers made very bad hash functions, so get rid
of them.  This completes the work of 689de1d6ca.

To avoid the inefficiency which was the motivation for the "simplified"
multipliers, hash_64() on 32-bit systems is changed to use a different
algorithm.  It makes two calls to hash_32() instead.

drivers/media/usb/dvb-usb-v2/af9015.c uses the old GOLDEN_RATIO_PRIME_32
for some horrible reason, so it inherits a copy of the old definition.

Signed-off-by: George Spelvin &lt;linux@sciencehorizons.net&gt;
Cc: Antti Palosaari &lt;crope@iki.fi&gt;
Cc: Mauro Carvalho Chehab &lt;m.chehab@samsung.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>remove lots of IS_ERR_VALUE abuses</title>
<updated>2016-05-27T22:26:11+00:00</updated>
<author>
<name>Arnd Bergmann</name>
<email>arnd@arndb.de</email>
</author>
<published>2016-05-27T21:23:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=287980e49ffc0f6d911601e7e352a812ed27768e'/>
<id>287980e49ffc0f6d911601e7e352a812ed27768e</id>
<content type='text'>
Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err &lt; 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL &amp;&amp; \
       unlikely((unsigned long long)(x) &gt;= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Andrzej Hajda &lt;a.hajda@samsung.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt; # For nvmem part
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
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Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err &lt; 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL &amp;&amp; \
       unlikely((unsigned long long)(x) &gt;= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Andrzej Hajda &lt;a.hajda@samsung.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla &lt;srinivas.kandagatla@linaro.org&gt; # For nvmem part
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
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