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<title>BMC/Intel-BMC/linux.git/arch/arm64, branch dev-4.6</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.6</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.6'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/'/>
<updated>2016-06-24T17:22:03+00:00</updated>
<entry>
<title>arm64: mm: always take dirty state from new pte in ptep_set_access_flags</title>
<updated>2016-06-24T17:22:03+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2016-06-07T16:55:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=24ba19ec0ae2add10b8788bfcf6963030ef37dcd'/>
<id>urn:sha1:24ba19ec0ae2add10b8788bfcf6963030ef37dcd</id>
<content type='text'>
commit 0106d456c4cb1770253fefc0ab23c9ca760b43f7 upstream.

Commit 66dbd6e61a52 ("arm64: Implement ptep_set_access_flags() for
hardware AF/DBM") ensured that pte flags are updated atomically in the
face of potential concurrent, hardware-assisted updates. However, Alex
reports that:

 | This patch breaks swapping for me.
 | In the broken case, you'll see either systemd cpu time spike (because
 | it's stuck in a page fault loop) or the system hang (because the
 | application owning the screen is stuck in a page fault loop).

It turns out that this is because the 'dirty' argument to
ptep_set_access_flags is always 0 for read faults, and so we can't use
it to set PTE_RDONLY. The failing sequence is:

  1. We put down a PTE_WRITE | PTE_DIRTY | PTE_AF pte
  2. Memory pressure -&gt; pte_mkold(pte) -&gt; clear PTE_AF
  3. A read faults due to the missing access flag
  4. ptep_set_access_flags is called with dirty = 0, due to the read fault
  5. pte is then made PTE_WRITE | PTE_DIRTY | PTE_AF | PTE_RDONLY (!)
  6. A write faults, but pte_write is true so we get stuck

The solution is to check the new page table entry (as would be done by
the generic, non-atomic definition of ptep_set_access_flags that just
calls set_pte_at) to establish the dirty state.

Fixes: 66dbd6e61a52 ("arm64: Implement ptep_set_access_flags() for hardware AF/DBM")
Reviewed-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Reported-by: Alexander Graf &lt;agraf@suse.de&gt;
Tested-by: Alexander Graf &lt;agraf@suse.de&gt;
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>arm64: Provide "model name" in /proc/cpuinfo for PER_LINUX32 tasks</title>
<updated>2016-06-24T17:22:03+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2016-05-31T14:55:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=60a61375d80d04eacec563807daaee639ba08443'/>
<id>urn:sha1:60a61375d80d04eacec563807daaee639ba08443</id>
<content type='text'>
commit e47b020a323d1b2a7b1e9aac86e99eae19463630 upstream.

This patch brings the PER_LINUX32 /proc/cpuinfo format more in line with
the 32-bit ARM one by providing an additional line:

model name      : ARMv8 Processor rev X (v8l)

Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
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>KVM: arm/arm64: vgic-v3: Clear all dirty LRs</title>
<updated>2016-06-24T17:22:01+00:00</updated>
<author>
<name>Christoffer Dall</name>
<email>christoffer.dall@linaro.org</email>
</author>
<published>2016-05-25T14:26:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=f25ef62ec07b063ec87be042ec0a84be6307d899'/>
<id>urn:sha1:f25ef62ec07b063ec87be042ec0a84be6307d899</id>
<content type='text'>
commit fa89c77e891917b5913f9be080f9131a9457bb3e upstream.

When saving the state of the list registers, it is critical to
reset them zero, as we could otherwise leave unexpected EOI
interrupts pending for virtual level interrupts.

Signed-off-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>kvm: arm64: Fix EC field in inject_abt64</title>
<updated>2016-06-01T19:17:58+00:00</updated>
<author>
<name>Matt Evans</name>
<email>matt.evans@arm.com</email>
</author>
<published>2016-05-16T12:54:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=dbc110f26d44b6bda56c6f9c07429970518adccd'/>
<id>urn:sha1:dbc110f26d44b6bda56c6f9c07429970518adccd</id>
<content type='text'>
commit e4fe9e7dc3828bf6a5714eb3c55aef6260d823a2 upstream.

The EC field of the constructed ESR is conditionally modified by ORing in
ESR_ELx_EC_DABT_LOW for a data abort.  However, ESR_ELx_EC_SHIFT is missing
from this condition.

Signed-off-by: Matt Evans &lt;matt.evans@arm.com&gt;
Acked-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Signed-off-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
</entry>
<entry>
<title>arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str</title>
<updated>2016-06-01T19:17:57+00:00</updated>
<author>
<name>Julien Grall</name>
<email>julien.grall@arm.com</email>
</author>
<published>2016-05-10T14:40:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ebe381c0a4ab69f88b502b3dfd3d489202cd0073'/>
<id>urn:sha1:ebe381c0a4ab69f88b502b3dfd3d489202cd0073</id>
<content type='text'>
commit f228b494e56d949be8d8ea09d4f973d1979201bf upstream.

The loop that browses the array compat_hwcap_str will stop when a NULL
is encountered, however NULL is missing at the end of array. This will
lead to overrun until a NULL is found somewhere in the following memory.
In reality, this works out because the compat_hwcap2_str array tends to
follow immediately in memory, and that *is* terminated correctly.
Furthermore, the unsigned int compat_elf_hwcap is checked before
printing each capability, so we end up doing the right thing because
the size of the two arrays is less than 32. Still, this is an obvious
mistake and should be fixed.

Note for backporting: commit 12d11817eaafa414 ("arm64: Move
/proc/cpuinfo handling code") moved this code in v4.4. Prior to that
commit, the same change should be made in arch/arm64/kernel/setup.c.

Fixes: 44b82b7700d0 "arm64: Fix up /proc/cpuinfo"
Signed-off-by: Julien Grall &lt;julien.grall@arm.com&gt;
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>arm64: Implement pmdp_set_access_flags() for hardware AF/DBM</title>
<updated>2016-06-01T19:17:57+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2016-05-05T09:44:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=b987714532522c6507e1b01a0ffdbf5649fdd64a'/>
<id>urn:sha1:b987714532522c6507e1b01a0ffdbf5649fdd64a</id>
<content type='text'>
commit 282aa7051b0169991b34716f0f22d9c2f59c46c4 upstream.

The update to the accessed or dirty states for block mappings must be
done atomically on hardware with support for automatic AF/DBM. The
ptep_set_access_flags() function has been fixed as part of commit
66dbd6e61a52 ("arm64: Implement ptep_set_access_flags() for hardware
AF/DBM"). This patch brings pmdp_set_access_flags() in line with the pte
counterpart.

Fixes: 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits")
Reviewed-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
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>arm64: Implement ptep_set_access_flags() for hardware AF/DBM</title>
<updated>2016-06-01T19:17:57+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2016-04-13T15:01:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=433dcefb09dea5ca0a419b383d3756052647ac43'/>
<id>urn:sha1:433dcefb09dea5ca0a419b383d3756052647ac43</id>
<content type='text'>
commit 66dbd6e61a526ae7d11a208238ae2c17e5cacb6b upstream.

When hardware updates of the access and dirty states are enabled, the
default ptep_set_access_flags() implementation based on calling
set_pte_at() directly is potentially racy. This triggers the "racy dirty
state clearing" warning in set_pte_at() because an existing writable PTE
is overridden with a clean entry.

There are two main scenarios for this situation:

1. The CPU getting an access fault does not support hardware updates of
   the access/dirty flags. However, a different agent in the system
   (e.g. SMMU) can do this, therefore overriding a writable entry with a
   clean one could potentially lose the automatically updated dirty
   status

2. A more complex situation is possible when all CPUs support hardware
   AF/DBM:

   a) Initial state: shareable + writable vma and pte_none(pte)
   b) Read fault taken by two threads of the same process on different
      CPUs
   c) CPU0 takes the mmap_sem and proceeds to handling the fault. It
      eventually reaches do_set_pte() which sets a writable + clean pte.
      CPU0 releases the mmap_sem
   d) CPU1 acquires the mmap_sem and proceeds to handle_pte_fault(). The
      pte entry it reads is present, writable and clean and it continues
      to pte_mkyoung()
   e) CPU1 calls ptep_set_access_flags()

   If between (d) and (e) the hardware (another CPU) updates the dirty
   state (clears PTE_RDONLY), CPU1 will override the PTR_RDONLY bit
   marking the entry clean again.

This patch implements an arm64-specific ptep_set_access_flags() function
to perform an atomic update of the PTE flags.

Fixes: 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits")
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Reported-by: Ming Lei &lt;tom.leiming@gmail.com&gt;
Tested-by: Julien Grall &lt;julien.grall@arm.com&gt;
Cc: Will Deacon &lt;will.deacon@arm.com&gt;
[will: reworded comment]
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>arm64: Ensure pmd_present() returns false after pmd_mknotpresent()</title>
<updated>2016-06-01T19:17:57+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2016-05-05T09:44:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=790cf8cf5c2f62caed41a93a3508eac91e4d31d0'/>
<id>urn:sha1:790cf8cf5c2f62caed41a93a3508eac91e4d31d0</id>
<content type='text'>
commit 5bb1cc0ff9a6b68871970737e6c4c16919928d8b upstream.

Currently, pmd_present() only checks for a non-zero value, returning
true even after pmd_mknotpresent() (which only clears the type bits).
This patch converts pmd_present() to using pte_present(), similar to the
other pmd_*() checks. As a side effect, it will return true for
PROT_NONE mappings, though they are not yet used by the kernel with
transparent huge pages.

For consistency, also change pmd_mknotpresent() to only clear the
PMD_SECT_VALID bit, even though the PMD_TABLE_BIT is already 0 for block
mappings (no functional change). The unused PMD_SECT_PROT_NONE
definition is removed as transparent huge pages use the pte page prot
values.

Fixes: 9c7e535fcc17 ("arm64: mm: Route pmd thp functions through pte equivalents")
Reviewed-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
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>arm64: Fix typo in the pmdp_huge_get_and_clear() definition</title>
<updated>2016-06-01T19:17:57+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2016-05-05T09:43:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=8f2bc2a8f1bfd36cb4be9ca15ad320259e8f1263'/>
<id>urn:sha1:8f2bc2a8f1bfd36cb4be9ca15ad320259e8f1263</id>
<content type='text'>
commit 911f56eeb87ee378f5e215469268a7a2f68a5a8a upstream.

With hardware AF/DBM support, pmd modifications (transparent huge pages)
should be performed atomically using load/store exclusive. The initial
patches defined the get-and-clear function and __HAVE_ARCH_* macro
without the "huge" word, leaving the pmdp_huge_get_and_clear() to the
default, non-atomic implementation.

Fixes: 2f4b829c625e ("arm64: Add support for hardware updates of the access and dirty pte bits")
Reviewed-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
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>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</title>
<updated>2016-05-14T21:15:06+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-05-14T21:15:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=272911b889f47aa5bc3e004804fc2382f0ac6ce6'/>
<id>urn:sha1:272911b889f47aa5bc3e004804fc2382f0ac6ce6</id>
<content type='text'>
Pull networking fixes from David Miller:

 1) Fix mvneta/bm dependencies, from Arnd Bergmann.

 2) RX completion hw bug workaround in bnxt_en, from Michael Chan.

 3) Kernel pointer leak in nf_conntrack, from Linus.

 4) Hoplimit route attribute limits not enforced properly, from Paolo
    Abeni.

 5) qlcnic driver NULL deref fix from Dan Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  arm64: bpf: jit JMP_JSET_{X,K}
  net/route: enforce hoplimit max value
  nf_conntrack: avoid kernel pointer value leak in slab name
  drivers: net: xgene: fix register offset
  drivers: net: xgene: fix statistics counters race condition
  drivers: net: xgene: fix ununiform latency across queues
  drivers: net: xgene: fix sharing of irqs
  drivers: net: xgene: fix IPv4 forward crash
  xen-netback: fix extra_info handling in xenvif_tx_err()
  net: mvneta: bm: fix dependencies again
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 2)
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 1)
  qlcnic: potential NULL dereference in qlcnic_83xx_get_minidump_template()
</content>
</entry>
</feed>
