<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/tile/include/asm/uaccess.h, branch v4.4.156</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>Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile</title>
<updated>2015-07-01T04:47:12+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-07-01T04:47:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=05a8256c586ab75bcd6b793737b2022a1a98cb1e'/>
<id>05a8256c586ab75bcd6b793737b2022a1a98cb1e</id>
<content type='text'>
Pull arch/tile updates from Chris Metcalf:
 "These are a grab bag of changes to improve debugging and respond to a
  variety of issues raised on LKML over the last couple of months"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: avoid a "label not used" warning in do_page_fault()
  tile: vdso: use raw_read_seqcount_begin() in vdso
  tile: force CONFIG_TILEGX if ARCH != tilepro
  tile: improve stack backtrace
  tile: fix "odd fault" warning for stack backtraces
  tile: set up initial stack top to honor STACK_TOP_DELTA
  tile: support delivering NMIs for multicore backtrace
  drivers/tty/hvc/hvc_tile.c: properly return -EAGAIN
  tile: add &lt;asm/word-at-a-time.h&gt; and enable support functions
  tile: use READ_ONCE() in arch_spin_is_locked()
  tile: modify arch_spin_unlock_wait() semantics
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull arch/tile updates from Chris Metcalf:
 "These are a grab bag of changes to improve debugging and respond to a
  variety of issues raised on LKML over the last couple of months"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: avoid a "label not used" warning in do_page_fault()
  tile: vdso: use raw_read_seqcount_begin() in vdso
  tile: force CONFIG_TILEGX if ARCH != tilepro
  tile: improve stack backtrace
  tile: fix "odd fault" warning for stack backtraces
  tile: set up initial stack top to honor STACK_TOP_DELTA
  tile: support delivering NMIs for multicore backtrace
  drivers/tty/hvc/hvc_tile.c: properly return -EAGAIN
  tile: add &lt;asm/word-at-a-time.h&gt; and enable support functions
  tile: use READ_ONCE() in arch_spin_is_locked()
  tile: modify arch_spin_unlock_wait() semantics
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/uaccess, mm/fault: Clarify that uaccess may only sleep if pagefaults are enabled</title>
<updated>2015-05-19T06:39:14+00:00</updated>
<author>
<name>David Hildenbrand</name>
<email>dahi@linux.vnet.ibm.com</email>
</author>
<published>2015-05-11T15:52:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b3c395ef5556a6c60f4426cc060f5b7bdcf82d5b'/>
<id>b3c395ef5556a6c60f4426cc060f5b7bdcf82d5b</id>
<content type='text'>
In general, non-atomic variants of user access functions must not sleep
if pagefaults are disabled.

Let's update all relevant comments in uaccess code. This also reflects
the might_sleep() checks in might_fault().

Reviewed-and-tested-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: David Hildenbrand &lt;dahi@linux.vnet.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-4-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In general, non-atomic variants of user access functions must not sleep
if pagefaults are disabled.

Let's update all relevant comments in uaccess code. This also reflects
the might_sleep() checks in might_fault().

Reviewed-and-tested-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: David Hildenbrand &lt;dahi@linux.vnet.ibm.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: airlied@linux.ie
Cc: akpm@linux-foundation.org
Cc: benh@kernel.crashing.org
Cc: bigeasy@linutronix.de
Cc: borntraeger@de.ibm.com
Cc: daniel.vetter@intel.com
Cc: heiko.carstens@de.ibm.com
Cc: herbert@gondor.apana.org.au
Cc: hocko@suse.cz
Cc: hughd@google.com
Cc: mst@redhat.com
Cc: paulus@samba.org
Cc: ralf@linux-mips.org
Cc: schwidefsky@de.ibm.com
Cc: yang.shi@windriver.com
Link: http://lkml.kernel.org/r/1431359540-32227-4-git-send-email-dahi@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: add &lt;asm/word-at-a-time.h&gt; and enable support functions</title>
<updated>2015-04-30T19:23:37+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@ezchip.com</email>
</author>
<published>2015-04-30T19:12:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=5bf6c07a1843813d0065feaaecba622d49148d7e'/>
<id>5bf6c07a1843813d0065feaaecba622d49148d7e</id>
<content type='text'>
This change enables the generic strncpy_from_user() and strnlen_user()
using word-at-a-time.h.  The tile implementation is trivial since
both tilepro and tilegx have SIMD operations that do byte-wise
comparisons against immediate zero for each byte, and return an
0x01 byte in each position where there is a 0x00 byte.

Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This change enables the generic strncpy_from_user() and strnlen_user()
using word-at-a-time.h.  The tile implementation is trivial since
both tilepro and tilegx have SIMD operations that do byte-wise
comparisons against immediate zero for each byte, and return an
0x01 byte in each position where there is a 0x00 byte.

Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: enable sparse checks for get/put_user</title>
<updated>2015-01-13T23:44:34+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@ezchip.com</email>
</author>
<published>2015-01-13T19:41:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b9f705758a4faaf86532bddf6ea3c50d6778ba42'/>
<id>b9f705758a4faaf86532bddf6ea3c50d6778ba42</id>
<content type='text'>
Add an extra intermediate variable to __get_user and __put_user
to give sparse an opportunity to detect mismatches.

Reviewed-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add an extra intermediate variable to __get_user and __put_user
to give sparse an opportunity to detect mismatches.

Reviewed-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: fix put_user sparse errors</title>
<updated>2015-01-13T23:44:17+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@ezchip.com</email>
</author>
<published>2015-01-13T19:39:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f3c927125fa49a42d596434d1ed454195c0d4530'/>
<id>f3c927125fa49a42d596434d1ed454195c0d4530</id>
<content type='text'>
Use x86's __inttype macro instead of using the typeof(x-x) trick to
generate a suitable integer size type.  This avoids a sparse warning
when examining the x-x type with a bitwise type.

Reviewed-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Use x86's __inttype macro instead of using the typeof(x-x) trick to
generate a suitable integer size type.  This avoids a sparse warning
when examining the x-x type with a bitwise type.

Reviewed-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: use proper .align directives on __ex_table sections</title>
<updated>2013-08-30T15:56:11+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@tilera.com</email>
</author>
<published>2013-08-09T19:38:43+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d4d9eab4ade468b6a97b6853fdd72e8f21474324'/>
<id>d4d9eab4ade468b6a97b6853fdd72e8f21474324</id>
<content type='text'>
This may fix a reported bug where an R_TILEGX_64 in a module was not
pointing to an aligned address.

Reported-by: Simon Marchi &lt;simon.marchi@polymtl.ca&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This may fix a reported bug where an R_TILEGX_64 in a module was not
pointing to an aligned address.

Reported-by: Simon Marchi &lt;simon.marchi@polymtl.ca&gt;
Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: convert uses of "inv" to "finv"</title>
<updated>2013-07-31T15:51:19+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@tilera.com</email>
</author>
<published>2013-07-23T21:32:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=dd78bc11fb2050b6a3990d0421feca4c68ca4335'/>
<id>dd78bc11fb2050b6a3990d0421feca4c68ca4335</id>
<content type='text'>
The "inv" (invalidate) instruction is generally less safe than "finv"
(flush and invalidate), as it will drop dirty data from the cache.
It turns out we have almost no need for "inv" (other than for the
older 32-bit architecture in some limited cases), so convert to
"finv" where possible and delete the extra "inv" infrastructure.

Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The "inv" (invalidate) instruction is generally less safe than "finv"
(flush and invalidate), as it will drop dirty data from the cache.
It turns out we have almost no need for "inv" (other than for the
older 32-bit architecture in some limited cases), so convert to
"finv" where possible and delete the extra "inv" infrastructure.

Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: uaccess s/might_sleep/might_fault/</title>
<updated>2013-05-28T07:41:09+00:00</updated>
<author>
<name>Michael S. Tsirkin</name>
<email>mst@redhat.com</email>
</author>
<published>2013-05-26T14:31:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f8abe86cc4fbd4ba083fd151b88e02fb3ce88b9c'/>
<id>f8abe86cc4fbd4ba083fd151b88e02fb3ce88b9c</id>
<content type='text'>
The only reason uaccess routines might sleep
is if they fault. Make this explicit.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Acked-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1369577426-26721-8-git-send-email-mst@redhat.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The only reason uaccess routines might sleep
is if they fault. Make this explicit.

Signed-off-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Acked-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;a.p.zijlstra@chello.nl&gt;
Link: http://lkml.kernel.org/r/1369577426-26721-8-git-send-email-mst@redhat.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Kconfig: consolidate CONFIG_DEBUG_STRICT_USER_COPY_CHECKS</title>
<updated>2013-05-01T00:04:09+00:00</updated>
<author>
<name>Stephen Boyd</name>
<email>sboyd@codeaurora.org</email>
</author>
<published>2013-04-30T22:28:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=446f24d1199e8a546ba7c97da3fbb9a505a94795'/>
<id>446f24d1199e8a546ba7c97da3fbb9a505a94795</id>
<content type='text'>
The help text for this config is duplicated across the x86, parisc, and
s390 Kconfig.debug files.  Arnd Bergman noted that the help text was
slightly misleading and should be fixed to state that enabling this
option isn't a problem when using pre 4.4 gcc.

To simplify the rewording, consolidate the text into lib/Kconfig.debug
and modify it there to be more explicit about when you should say N to
this config.

Also, make the text a bit more generic by stating that this option
enables compile time checks so we can cover architectures which emit
warnings vs.  ones which emit errors.  The details of how an
architecture decided to implement the checks isn't as important as the
concept of compile time checking of copy_from_user() calls.

While we're doing this, remove all the copy_from_user_overflow() code
that's duplicated many times and place it into lib/ so that any
architecture supporting this option can get the function for free.

Signed-off-by: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Acked-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Acked-by: Helge Deller &lt;deller@gmx.de&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Chris Metcalf &lt;cmetcalf@tilera.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>
The help text for this config is duplicated across the x86, parisc, and
s390 Kconfig.debug files.  Arnd Bergman noted that the help text was
slightly misleading and should be fixed to state that enabling this
option isn't a problem when using pre 4.4 gcc.

To simplify the rewording, consolidate the text into lib/Kconfig.debug
and modify it there to be more explicit about when you should say N to
this config.

Also, make the text a bit more generic by stating that this option
enables compile time checks so we can cover architectures which emit
warnings vs.  ones which emit errors.  The details of how an
architecture decided to implement the checks isn't as important as the
concept of compile time checking of copy_from_user() calls.

While we're doing this, remove all the copy_from_user_overflow() code
that's duplicated many times and place it into lib/ so that any
architecture supporting this option can get the function for free.

Signed-off-by: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Acked-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Acked-by: Helge Deller &lt;deller@gmx.de&gt;
Cc: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Cc: Stephen Rothwell &lt;sfr@canb.auug.org.au&gt;
Cc: Chris Metcalf &lt;cmetcalf@tilera.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>tile: fix bug in get_user() for 4-byte values</title>
<updated>2012-06-16T20:56:13+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@tilera.com</email>
</author>
<published>2012-06-16T20:53:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6699c8cda36f296e315068ed9bbe4f03e6ed4044'/>
<id>6699c8cda36f296e315068ed9bbe4f03e6ed4044</id>
<content type='text'>
The definition of 32-bit values in the 64-bit tilegx architecture is that
they should be sign-extended regardless of whether they are considered
signed or unsigned by the compiler.  Accordingly, we need to use an
"ld4s" rather than "ld4u" to load and sign-extend for get_user().

This fixes glibc bug 14238 (see http://sourceware.org/bugzilla),
introduced during the 3.5 merge window.

Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The definition of 32-bit values in the 64-bit tilegx architecture is that
they should be sign-extended regardless of whether they are considered
signed or unsigned by the compiler.  Accordingly, we need to use an
"ld4s" rather than "ld4u" to load and sign-extend for get_user().

This fixes glibc bug 14238 (see http://sourceware.org/bugzilla),
introduced during the 3.5 merge window.

Signed-off-by: Chris Metcalf &lt;cmetcalf@tilera.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
