<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/s390/mm, branch v3.10.61</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>arch: mm: pass userspace fault flag to generic fault handler</title>
<updated>2014-11-21T17:22:56+00:00</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2013-09-12T22:13:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e2ec2c2b96808afa2f57ec7d7949691146fca341'/>
<id>e2ec2c2b96808afa2f57ec7d7949691146fca341</id>
<content type='text'>
commit 759496ba6407c6994d6a5ce3a5e74937d7816208 upstream.

Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.

Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.

Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Reviewed-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: KAMEZAWA Hiroyuki &lt;kamezawa.hiroyu@jp.fujitsu.com&gt;
Cc: azurIt &lt;azurit@pobox.sk&gt;
Cc: KOSAKI Motohiro &lt;kosaki.motohiro@jp.fujitsu.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 759496ba6407c6994d6a5ce3a5e74937d7816208 upstream.

Unlike global OOM handling, memory cgroup code will invoke the OOM killer
in any OOM situation because it has no way of telling faults occuring in
kernel context - which could be handled more gracefully - from
user-triggered faults.

Pass a flag that identifies faults originating in user space from the
architecture-specific fault handlers to generic code so that memcg OOM
handling can be improved.

Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Reviewed-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: KAMEZAWA Hiroyuki &lt;kamezawa.hiroyu@jp.fujitsu.com&gt;
Cc: azurIt &lt;azurit@pobox.sk&gt;
Cc: KOSAKI Motohiro &lt;kosaki.motohiro@jp.fujitsu.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Cong Wang &lt;xiyou.wangcong@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390/dump: Fix dump memory detection</title>
<updated>2014-02-22T20:41:26+00:00</updated>
<author>
<name>Michael Holzheu</name>
<email>holzheu@linux.vnet.ibm.com</email>
</author>
<published>2014-01-30T15:14:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=312cdf57ee8b7ef9ae1967e243a770dc5557af05'/>
<id>312cdf57ee8b7ef9ae1967e243a770dc5557af05</id>
<content type='text'>
commit d7736ff5be31edaa4fe5ab62810c64529a24b149 upstream.

Dumps created by kdump or zfcpdump can contain invalid memory holes when
dumping z/VM systems that have memory pressure.

For example:

   # zgetdump -i /proc/vmcore.
   Memory map:
   0000000000000000 - 0000000000bfffff (12 MB)
   0000000000e00000 - 00000000014fffff (7 MB)
   000000000bd00000 - 00000000f3bfffff (3711 MB)

The memory detection function find_memory_chunks() issues tprot to
find valid memory chunks. In case of CMM it can happen that pages are
marked as unstable via set_page_unstable() in arch_free_page().
If z/VM has released that pages, tprot returns -EFAULT and indicates
a memory hole.

So fix this and switch off CMM in case of kdump or zfcpdump.

Signed-off-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d7736ff5be31edaa4fe5ab62810c64529a24b149 upstream.

Dumps created by kdump or zfcpdump can contain invalid memory holes when
dumping z/VM systems that have memory pressure.

For example:

   # zgetdump -i /proc/vmcore.
   Memory map:
   0000000000000000 - 0000000000bfffff (12 MB)
   0000000000e00000 - 00000000014fffff (7 MB)
   000000000bd00000 - 00000000f3bfffff (3711 MB)

The memory detection function find_memory_chunks() issues tprot to
find valid memory chunks. In case of CMM it can happen that pages are
marked as unstable via set_page_unstable() in arch_free_page().
If z/VM has released that pages, tprot returns -EFAULT and indicates
a memory hole.

So fix this and switch off CMM in case of kdump or zfcpdump.

Signed-off-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390: add support for IBM zBC12 machine</title>
<updated>2013-08-12T01:35:25+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2013-07-24T08:35:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=72e2729ea923cbbbeda03e5fce14f50b0707f724'/>
<id>72e2729ea923cbbbeda03e5fce14f50b0707f724</id>
<content type='text'>
commit 594712276e737961d30e11eae80d403b2b3815df upstream.

Just add the new model number where appropiate.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 594712276e737961d30e11eae80d403b2b3815df upstream.

Just add the new model number where appropiate.

Signed-off-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390/mem_detect: fix memory hole handling</title>
<updated>2013-06-19T13:36:16+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2013-06-19T07:16:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=35b03aec919c952e67b0b093638e0d79b468f9bc'/>
<id>35b03aec919c952e67b0b093638e0d79b468f9bc</id>
<content type='text'>
With git commit 996b4a7d "s390/mem_detect: remove artificial kdump
memory types" the memory detection code got simplified.
As a side effect the array that describes memory chunks may now
contain empty (zeroed) entries.
All call sites can handle this except for

drivers/s390/char/zcore.c::zcore_memmap_open

which has a really odd user space interface. The easiest fix is to
change the memory hole handling code, so that no empty entries exist
before the last valid entry is reached.

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>
With git commit 996b4a7d "s390/mem_detect: remove artificial kdump
memory types" the memory detection code got simplified.
As a side effect the array that describes memory chunks may now
contain empty (zeroed) entries.
All call sites can handle this except for

drivers/s390/char/zcore.c::zcore_memmap_open

which has a really odd user space interface. The easiest fix is to
change the memory hole handling code, so that no empty entries exist
before the last valid entry is reached.

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>s390/pgtable: Fix gmap notifier address</title>
<updated>2013-05-31T15:23:53+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2013-05-29T11:08:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e86cbd8765bd2e1f9eeb209822449c9b1e5958cf'/>
<id>e86cbd8765bd2e1f9eeb209822449c9b1e5958cf</id>
<content type='text'>
The address of the gmap notifier was broken, resulting in
unhandled validity intercepts in KVM. Fix the rmap-&gt;vmaddr
to be on a segment boundary.

Signed-off-by: Christian Borntraeger &lt;borntraeger@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>
The address of the gmap notifier was broken, resulting in
unhandled validity intercepts in KVM. Fix the rmap-&gt;vmaddr
to be on a segment boundary.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390: fix gmap_ipte_notifier vs. software dirty pages</title>
<updated>2013-05-15T11:09:07+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2013-05-08T13:25:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=bb4b42ce0ca36af8c113587ab64b138b3cf5459c'/>
<id>bb4b42ce0ca36af8c113587ab64b138b3cf5459c</id>
<content type='text'>
On heavy paging load some guest cpus started to loop in gmap_ipte_notify.
This was visible as stalled cpus inside the guest. The gmap_ipte_notifier
tries to map a user page and then made sure that the pte is valid and
writable. Turns out that with the software change bit tracking the pte
can become read-only (and only software writable) if the page is clean.
Since we loop in this code, the page would stay clean and, therefore,
be never writable again.
Let us just use fixup_user_fault, that guarantees to call handle_mm_fault.

Signed-off-by: Christian Borntraeger &lt;borntraeger@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>
On heavy paging load some guest cpus started to loop in gmap_ipte_notify.
This was visible as stalled cpus inside the guest. The gmap_ipte_notifier
tries to map a user page and then made sure that the pte is valid and
writable. Turns out that with the software change bit tracking the pte
can become read-only (and only software writable) if the page is clean.
Since we loop in this code, the page would stay clean and, therefore,
be never writable again.
Let us just use fixup_user_fault, that guarantees to call handle_mm_fault.

Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/mem_detect: remove artificial kdump memory types</title>
<updated>2013-05-03T12:21:15+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2013-04-30T17:19:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=996b4a7d8f4e5dd531369396f2312b97e9400cdc'/>
<id>996b4a7d8f4e5dd531369396f2312b97e9400cdc</id>
<content type='text'>
Simplify the memory detection code a bit by removing the CHUNK_OLDMEM
and CHUNK_CRASHK memory types.
They are not needed. Everything that is needed is a mechanism to
insert holes into the detected memory.

Reviewed-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.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>
Simplify the memory detection code a bit by removing the CHUNK_OLDMEM
and CHUNK_CRASHK memory types.
They are not needed. Everything that is needed is a mechanism to
insert holes into the detected memory.

Reviewed-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.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>s390/mm: add pte invalidation notifier for kvm</title>
<updated>2013-05-03T12:21:12+00:00</updated>
<author>
<name>Martin Schwidefsky</name>
<email>schwidefsky@de.ibm.com</email>
</author>
<published>2013-04-17T08:53:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d3383632d4e8e9ae747f582eaee8c2e79f828ae6'/>
<id>d3383632d4e8e9ae747f582eaee8c2e79f828ae6</id>
<content type='text'>
Add a notifier for kvm to get control before a page table entry is
invalidated. The notifier is only called for ptes of an address space
with pgstes that have been explicitly marked to require notification.
Kvm will use this to get control before prefix pages of virtual CPU
are unmapped.

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add a notifier for kvm to get control before a page table entry is
invalidated. The notifier is only called for ptes of an address space
with pgstes that have been explicitly marked to require notification.
Kvm will use this to get control before prefix pages of virtual CPU
are unmapped.

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>s390/memory hotplug: provide memory_block_size_bytes() function</title>
<updated>2013-05-02T13:50:27+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2013-05-02T07:15:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e5d709bb5fb758281b5a5dbda50823bb68b3a066'/>
<id>e5d709bb5fb758281b5a5dbda50823bb68b3a066</id>
<content type='text'>
Commit 0c2c99b1b "memory hotplug: Allow memory blocks to span
multiple memory sections" introduced a weak memory_block_size_bytes()
function which can be used to set the size of a memory block as
seen in sysfs.
Provide an s390 specific override which makes sure that each
memory block has at least a size of 256MB or the increment size of
of a memory increment, whatever is larger.
This way we can make sure that the number of memory sysfs objects
doesn't explode for very large memory configurations.

Reported-by: Gerald Schaefer &lt;gerald.schaefer@de.ibm.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>
Commit 0c2c99b1b "memory hotplug: Allow memory blocks to span
multiple memory sections" introduced a weak memory_block_size_bytes()
function which can be used to set the size of a memory block as
seen in sysfs.
Provide an s390 specific override which makes sure that each
memory block has at least a size of 256MB or the increment size of
of a memory increment, whatever is larger.
This way we can make sure that the number of memory sysfs objects
doesn't explode for very large memory configurations.

Reported-by: Gerald Schaefer &lt;gerald.schaefer@de.ibm.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>s390/mem_detect: limit memory detection loop to "mem=" parameter</title>
<updated>2013-05-02T13:50:26+00:00</updated>
<author>
<name>Heiko Carstens</name>
<email>heiko.carstens@de.ibm.com</email>
</author>
<published>2013-04-30T08:34:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=df1bd59c5cc247d1d02588ff0a4e86a0cc5f9733'/>
<id>df1bd59c5cc247d1d02588ff0a4e86a0cc5f9733</id>
<content type='text'>
The current memory detection loop will detect all present memory of
a machine. This is true even if the user specified the "mem=" parameter
on the kernel command line.
This can be a problem since the memory detection may cause a fully
populated host page table for the guest, even for those parts of the
memory that the guest will never use afterwards.

So fix this and only detect memory up to a user supplied "mem=" limit
if specified.

Reported-by: Michael Johanssen &lt;johanssn@de.ibm.com&gt;
Reviewed-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.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>
The current memory detection loop will detect all present memory of
a machine. This is true even if the user specified the "mem=" parameter
on the kernel command line.
This can be a problem since the memory detection may cause a fully
populated host page table for the guest, even for those parts of the
memory that the guest will never use afterwards.

So fix this and only detect memory up to a user supplied "mem=" limit
if specified.

Reported-by: Michael Johanssen &lt;johanssn@de.ibm.com&gt;
Reviewed-by: Michael Holzheu &lt;holzheu@linux.vnet.ibm.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>
</feed>
