<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/s390/kernel/compat_linux.c, branch v4.12</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>s390: kernel: Audit and remove any unnecessary uses of module.h</title>
<updated>2017-02-17T06:40:31+00:00</updated>
<author>
<name>Paul Gortmaker</name>
<email>paul.gortmaker@windriver.com</email>
</author>
<published>2017-02-09T20:20:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=3994a52b54569c4d71d43e3e00464eb9127f86a5'/>
<id>3994a52b54569c4d71d43e3e00464eb9127f86a5</id>
<content type='text'>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each change instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends.  That changed
when we forked out support for the latter into the export.h file.

This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig.  The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.

Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each change instance
for the presence of either and replace as needed.  Build testing
revealed some implicit header usage that was fixed up accordingly.

Signed-off-by: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Replace &lt;asm/uaccess.h&gt; with &lt;linux/uaccess.h&gt; globally</title>
<updated>2016-12-24T19:46:01+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-12-24T19:46:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7c0f6ba682b9c7632072ffbedf8d328c8f3c42ba'/>
<id>7c0f6ba682b9c7632072ffbedf8d328c8f3c42ba</id>
<content type='text'>
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*&lt;asm/uaccess.h&gt;'
  sed -i -e "s!$PATT!#include &lt;linux/uaccess.h&gt;!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro &lt;viro@zeniv.linux.org.uk&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>
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*&lt;asm/uaccess.h&gt;'
  sed -i -e "s!$PATT!#include &lt;linux/uaccess.h&gt;!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>cred: simpler, 1D supplementary groups</title>
<updated>2016-10-08T01:46:30+00:00</updated>
<author>
<name>Alexey Dobriyan</name>
<email>adobriyan@gmail.com</email>
</author>
<published>2016-10-08T00:03:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=81243eacfa400f5f7b89f4c2323d0de9982bb0fb'/>
<id>81243eacfa400f5f7b89f4c2323d0de9982bb0fb</id>
<content type='text'>
Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D
array.

If number of gids is &lt;= 32, memory allocation is more or less tolerable
(140/148 bytes).  But if it is not, code allocates full page (!)
regardless and, what's even more fun, doesn't reuse small 32-entry
array.

2D array means dependent shifts, loads and LEAs without possibility to
optimize them (gid is never known at compile time).

All of the above is unnecessary.  Switch to the usual
trailing-zero-len-array scheme.  Memory is allocated with
kmalloc/vmalloc() and only as much as needed.  Accesses become simpler
(LEA 8(gi,idx,4) or even without displacement).

Maximum number of gids is 65536 which translates to 256KB+8 bytes.  I
think kernel can handle such allocation.

On my usual desktop system with whole 9 (nine) aux groups, struct
group_info shrinks from 148 bytes to 44 bytes, yay!

Nice side effects:

 - "gi-&gt;gid[i]" is shorter than "GROUP_AT(gi, i)", less typing,

 - fix little mess in net/ipv4/ping.c
   should have been using GROUP_AT macro but this point becomes moot,

 - aux group allocation is persistent and should be accounted as such.

Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Vasily Kulikov &lt;segoon@openwall.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&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>
Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D
array.

If number of gids is &lt;= 32, memory allocation is more or less tolerable
(140/148 bytes).  But if it is not, code allocates full page (!)
regardless and, what's even more fun, doesn't reuse small 32-entry
array.

2D array means dependent shifts, loads and LEAs without possibility to
optimize them (gid is never known at compile time).

All of the above is unnecessary.  Switch to the usual
trailing-zero-len-array scheme.  Memory is allocated with
kmalloc/vmalloc() and only as much as needed.  Accesses become simpler
(LEA 8(gi,idx,4) or even without displacement).

Maximum number of gids is 65536 which translates to 256KB+8 bytes.  I
think kernel can handle such allocation.

On my usual desktop system with whole 9 (nine) aux groups, struct
group_info shrinks from 148 bytes to 44 bytes, yay!

Nice side effects:

 - "gi-&gt;gid[i]" is shorter than "GROUP_AT(gi, i)", less typing,

 - fix little mess in net/ipv4/ping.c
   should have been using GROUP_AT macro but this point becomes moot,

 - aux group allocation is persistent and should be accounted as such.

Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.by
Signed-off-by: Alexey Dobriyan &lt;adobriyan@gmail.com&gt;
Cc: Vasily Kulikov &lt;segoon@openwall.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>groups: Consolidate the setgroups permission checks</title>
<updated>2014-12-05T23:19:27+00:00</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2014-12-05T23:19:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7ff4d90b4c24a03666f296c3d4878cd39001e81e'/>
<id>7ff4d90b4c24a03666f296c3d4878cd39001e81e</id>
<content type='text'>
Today there are 3 instances of setgroups and due to an oversight their
permission checking has diverged.  Add a common function so that
they may all share the same permission checking code.

This corrects the current oversight in the current permission checks
and adds a helper to avoid this in the future.

A user namespace security fix will update this new helper, shortly.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Today there are 3 instances of setgroups and due to an oversight their
permission checking has diverged.  Add a common function so that
they may all share the same permission checking code.

This corrects the current oversight in the current permission checks
and adds a helper to avoid this in the future.

A user namespace security fix will update this new helper, shortly.

Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: add sync_file_range and fallocate compat syscalls</title>
<updated>2014-03-04T08:05:47+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-03-01T12:09:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c81fc4fb41f589454861bbdb90ffde73840b8f8'/>
<id>2c81fc4fb41f589454861bbdb90ffde73840b8f8</id>
<content type='text'>
The compat syscall wrappers for sync_file_range and fallocate merged 32 bit
parameters into 64 bit parameters. Therefore they did more than just the
usual zero and/or sign extension of system call parameters.

So convert these two wrappers to full s390 specific compat sytem calls.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The compat syscall wrappers for sync_file_range and fallocate merged 32 bit
parameters into 64 bit parameters. Therefore they did more than just the
usual zero and/or sign extension of system call parameters.

So convert these two wrappers to full s390 specific compat sytem calls.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 7</title>
<updated>2014-03-04T08:05:38+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-02-26T13:40:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=5383d2c8b3ee61a762043818d7c07bbc0049b031'/>
<id>5383d2c8b3ee61a762043818d7c07bbc0049b031</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 6</title>
<updated>2014-03-04T08:05:37+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-02-26T13:05:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=a0f8c6da8f3da63283e978ebece03e81d107b1d0'/>
<id>a0f8c6da8f3da63283e978ebece03e81d107b1d0</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 5</title>
<updated>2014-03-04T08:05:36+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-02-26T11:51:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=52a0b536a3addcfe20325303b2dddc2538019476'/>
<id>52a0b536a3addcfe20325303b2dddc2538019476</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 4</title>
<updated>2014-03-04T08:05:36+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-02-26T09:58:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e723e0cc17f8d8573b19a809277d81cecdd6e92b'/>
<id>e723e0cc17f8d8573b19a809277d81cecdd6e92b</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/compat: convert to COMPAT_SYSCALL_DEFINEx part 3</title>
<updated>2014-03-04T08:05:35+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2014-02-25T15:17:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=4ca2ea58c8421784bdad43b05e9939549e4d34e9'/>
<id>4ca2ea58c8421784bdad43b05e9939549e4d34e9</id>
<content type='text'>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
