<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/acpi, branch v4.10.3</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>nfit, libnvdimm: fix interleave set cookie calculation</title>
<updated>2017-03-15T02:20:13+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2017-03-01T02:32:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ea708e9581d87d7896be4760a066f8f6c9759ab4'/>
<id>ea708e9581d87d7896be4760a066f8f6c9759ab4</id>
<content type='text'>
commit 86ef58a4e35e8fa66afb5898cf6dec6a3bb29f67 upstream.

The interleave-set cookie is a sum that sanity checks the composition of
an interleave set has not changed from when the namespace was initially
created.  The checksum is calculated by sorting the DIMMs by their
location in the interleave-set. The comparison for the sort must be
64-bit wide, not byte-by-byte as performed by memcmp() in the broken
case.

Fix the implementation to accept correct cookie values in addition to
the Linux "memcmp" order cookies, but only allow correct cookies to be
generated going forward. It does mean that namespaces created by
third-party-tooling, or created by newer kernels with this fix, will not
validate on older kernels. However, there are a couple mitigating
conditions:

    1/ platforms with namespace-label capable NVDIMMs are not widely
       available.

    2/ interleave-sets with a single-dimm are by definition not affected
       (nothing to sort). This covers the QEMU-KVM NVDIMM emulation case.

The cookie stored in the namespace label will be fixed by any write the
namespace label, the most straightforward way to achieve this is to
write to the "alt_name" attribute of a namespace in sysfs.

Fixes: eaf961536e16 ("libnvdimm, nfit: add interleave-set state-tracking infrastructure")
Reported-by: Nicholas Moulin &lt;nicholas.w.moulin@linux.intel.com&gt;
Tested-by: Nicholas Moulin &lt;nicholas.w.moulin@linux.intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.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 86ef58a4e35e8fa66afb5898cf6dec6a3bb29f67 upstream.

The interleave-set cookie is a sum that sanity checks the composition of
an interleave set has not changed from when the namespace was initially
created.  The checksum is calculated by sorting the DIMMs by their
location in the interleave-set. The comparison for the sort must be
64-bit wide, not byte-by-byte as performed by memcmp() in the broken
case.

Fix the implementation to accept correct cookie values in addition to
the Linux "memcmp" order cookies, but only allow correct cookies to be
generated going forward. It does mean that namespaces created by
third-party-tooling, or created by newer kernels with this fix, will not
validate on older kernels. However, there are a couple mitigating
conditions:

    1/ platforms with namespace-label capable NVDIMMs are not widely
       available.

    2/ interleave-sets with a single-dimm are by definition not affected
       (nothing to sort). This covers the QEMU-KVM NVDIMM emulation case.

The cookie stored in the namespace label will be fixed by any write the
namespace label, the most straightforward way to achieve this is to
write to the "alt_name" attribute of a namespace in sysfs.

Fixes: eaf961536e16 ("libnvdimm, nfit: add interleave-set state-tracking infrastructure")
Reported-by: Nicholas Moulin &lt;nicholas.w.moulin@linux.intel.com&gt;
Tested-by: Nicholas Moulin &lt;nicholas.w.moulin@linux.intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm</title>
<updated>2017-02-07T03:36:04+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-02-07T03:36:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8b1b41ee74f9712c355d66dc105bbea663ae0afd'/>
<id>8b1b41ee74f9712c355d66dc105bbea663ae0afd</id>
<content type='text'>
Pull libnvdimm fixes from Dan Williams:
 "None of these are showstoppers for 4.10 and could wait for 4.11 merge
  window, but they are low enough risk for this late in the cycle and
  the fixes have waiting users . They have received a build success
  notification from the 0day robot, pass the latest ndctl unit tests,
  and appeared in next:

   - Fix a crash that can result when SIGINT is sent to a process that
     is awaiting completion of an address range scrub command. We were
     not properly cleaning up the workqueue after
     wait_event_interruptible().

   - Fix a memory hotplug failure condition that results from not
     reserving enough space out of persistent memory for the memmap. By
     default we align to 2M allocations that the memory hotplug code
     assumes, but if the administrator specifies a non-default
     4K-alignment then we can fail to correctly size the reservation.

   - A one line fix to improve the predictability of libnvdimm block
     device names. A common operation is to reconfigure /dev/pmem0 into
     a different mode. For example, a reconfiguration might set a new
     mode that reserves some of the capacity for a struct page memmap
     array. It surprises users if the device name changes to
     "/dev/pmem0.1" after the mode change and then back to /dev/pmem0
     after a reboot.

   - Add 'const' to some function pointer tables"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm, pfn: fix memmap reservation size versus 4K alignment
  acpi, nfit: fix acpi_nfit_flush_probe() crash
  libnvdimm, namespace: do not delete namespace-id 0
  nvdimm: constify device_type structures
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull libnvdimm fixes from Dan Williams:
 "None of these are showstoppers for 4.10 and could wait for 4.11 merge
  window, but they are low enough risk for this late in the cycle and
  the fixes have waiting users . They have received a build success
  notification from the 0day robot, pass the latest ndctl unit tests,
  and appeared in next:

   - Fix a crash that can result when SIGINT is sent to a process that
     is awaiting completion of an address range scrub command. We were
     not properly cleaning up the workqueue after
     wait_event_interruptible().

   - Fix a memory hotplug failure condition that results from not
     reserving enough space out of persistent memory for the memmap. By
     default we align to 2M allocations that the memory hotplug code
     assumes, but if the administrator specifies a non-default
     4K-alignment then we can fail to correctly size the reservation.

   - A one line fix to improve the predictability of libnvdimm block
     device names. A common operation is to reconfigure /dev/pmem0 into
     a different mode. For example, a reconfiguration might set a new
     mode that reserves some of the capacity for a struct page memmap
     array. It surprises users if the device name changes to
     "/dev/pmem0.1" after the mode change and then back to /dev/pmem0
     after a reboot.

   - Add 'const' to some function pointer tables"

* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm, pfn: fix memmap reservation size versus 4K alignment
  acpi, nfit: fix acpi_nfit_flush_probe() crash
  libnvdimm, namespace: do not delete namespace-id 0
  nvdimm: constify device_type structures
</pre>
</div>
</content>
</entry>
<entry>
<title>acpi, nfit: fix acpi_nfit_flush_probe() crash</title>
<updated>2017-02-03T19:47:36+00:00</updated>
<author>
<name>Dan Williams</name>
<email>dan.j.williams@intel.com</email>
</author>
<published>2017-02-02T18:31:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e471486c13b82b1338d49c798f78bb62b1ed0a9e'/>
<id>e471486c13b82b1338d49c798f78bb62b1ed0a9e</id>
<content type='text'>
We queue an on-stack work item to 'nfit_wq' and wait for it to complete
as part of a 'flush_probe' request. However, if the user cancels the
wait we need to make sure the item is flushed from the queue otherwise
we are leaving an out-of-scope stack address on the work list.

 BUG: unable to handle kernel paging request at ffffbcb3c72f7cd0
 IP: [&lt;ffffffffa9413a7b&gt;] __list_add+0x1b/0xb0
 [..]
 RIP: 0010:[&lt;ffffffffa9413a7b&gt;]  [&lt;ffffffffa9413a7b&gt;] __list_add+0x1b/0xb0
 RSP: 0018:ffffbcb3c7ba7c00  EFLAGS: 00010046
 [..]
 Call Trace:
  [&lt;ffffffffa90bb11a&gt;] insert_work+0x3a/0xc0
  [&lt;ffffffffa927fdda&gt;] ? seq_open+0x5a/0xa0
  [&lt;ffffffffa90bb30a&gt;] __queue_work+0x16a/0x460
  [&lt;ffffffffa90bbb08&gt;] queue_work_on+0x38/0x40
  [&lt;ffffffffc0cf2685&gt;] acpi_nfit_flush_probe+0x95/0xc0 [nfit]
  [&lt;ffffffffc0cf25d0&gt;] ? nfit_visible+0x40/0x40 [nfit]
  [&lt;ffffffffa9571495&gt;] wait_probe_show+0x25/0x60
  [&lt;ffffffffa9546b30&gt;] dev_attr_show+0x20/0x50

Fixes: 7ae0fa439faf ("nfit, libnvdimm: async region scrub workqueue")
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We queue an on-stack work item to 'nfit_wq' and wait for it to complete
as part of a 'flush_probe' request. However, if the user cancels the
wait we need to make sure the item is flushed from the queue otherwise
we are leaving an out-of-scope stack address on the work list.

 BUG: unable to handle kernel paging request at ffffbcb3c72f7cd0
 IP: [&lt;ffffffffa9413a7b&gt;] __list_add+0x1b/0xb0
 [..]
 RIP: 0010:[&lt;ffffffffa9413a7b&gt;]  [&lt;ffffffffa9413a7b&gt;] __list_add+0x1b/0xb0
 RSP: 0018:ffffbcb3c7ba7c00  EFLAGS: 00010046
 [..]
 Call Trace:
  [&lt;ffffffffa90bb11a&gt;] insert_work+0x3a/0xc0
  [&lt;ffffffffa927fdda&gt;] ? seq_open+0x5a/0xa0
  [&lt;ffffffffa90bb30a&gt;] __queue_work+0x16a/0x460
  [&lt;ffffffffa90bbb08&gt;] queue_work_on+0x38/0x40
  [&lt;ffffffffc0cf2685&gt;] acpi_nfit_flush_probe+0x95/0xc0 [nfit]
  [&lt;ffffffffc0cf25d0&gt;] ? nfit_visible+0x40/0x40 [nfit]
  [&lt;ffffffffa9571495&gt;] wait_probe_show+0x25/0x60
  [&lt;ffffffffa9546b30&gt;] dev_attr_show+0x20/0x50

Fixes: 7ae0fa439faf ("nfit, libnvdimm: async region scrub workqueue")
Cc: &lt;stable@vger.kernel.org&gt;
Reviewed-by: Vishal Verma &lt;vishal.l.verma@intel.com&gt;
Signed-off-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'acpi-4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2017-01-27T01:27:00+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-01-27T01:27:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2287a240a6b1c39fd06f94e57b8c0189c497efe5'/>
<id>2287a240a6b1c39fd06f94e57b8c0189c497efe5</id>
<content type='text'>
Pull ACPI fixes from Rafael Wysocki:
 "These fix two regressions introduced recently, one by reverting the
  problematic commit and one by fixing up locking in the ACPICA core.

  Specifics:

   - Revert a recent change that added an ACPI video blacklist entry for
     HP Pavilion dv6 as it turned to introduce backlight handling
     regressions on some systems (Hans de Goede).

   - Fix locking in the ACPICA core to avoid deadlocks related to table
     loading that were exposed by a recent change in that area (Lv
     Zheng)"

* tag 'acpi-4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"
  ACPICA: Tables: Fix hidden logic related to acpi_tb_install_standard_table()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ACPI fixes from Rafael Wysocki:
 "These fix two regressions introduced recently, one by reverting the
  problematic commit and one by fixing up locking in the ACPICA core.

  Specifics:

   - Revert a recent change that added an ACPI video blacklist entry for
     HP Pavilion dv6 as it turned to introduce backlight handling
     regressions on some systems (Hans de Goede).

   - Fix locking in the ACPICA core to avoid deadlocks related to table
     loading that were exposed by a recent change in that area (Lv
     Zheng)"

* tag 'acpi-4.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"
  ACPICA: Tables: Fix hidden logic related to acpi_tb_install_standard_table()
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'acpica' and 'acpi-video'</title>
<updated>2017-01-26T23:39:02+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2017-01-26T23:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0389227dde3abae442521948caf5c173e696cdca'/>
<id>0389227dde3abae442521948caf5c173e696cdca</id>
<content type='text'>
* acpica:
  ACPICA: Tables: Fix hidden logic related to acpi_tb_install_standard_table()

* acpi-video:
  Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* acpica:
  ACPICA: Tables: Fix hidden logic related to acpi_tb_install_standard_table()

* acpi-video:
  Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'pm-sleep' and 'pm-cpufreq'</title>
<updated>2017-01-26T23:08:59+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2017-01-26T23:08:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ff7e593c9cf3ccceaab7ac600cbd52cb9ff4c57a'/>
<id>ff7e593c9cf3ccceaab7ac600cbd52cb9ff4c57a</id>
<content type='text'>
* pm-sleep:
  Revert "PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag"

* pm-cpufreq:
  cpufreq: intel_pstate: Fix sysfs limits enforcement for performance policy
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* pm-sleep:
  Revert "PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag"

* pm-cpufreq:
  cpufreq: intel_pstate: Fix sysfs limits enforcement for performance policy
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"</title>
<updated>2017-01-25T13:04:13+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2017-01-22T12:24:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fd25ea29093e275195d0ae8b2573021a1c98959f'/>
<id>fd25ea29093e275195d0ae8b2573021a1c98959f</id>
<content type='text'>
Revert commit 6276e53fa8c0 (ACPI / video: Add force_native quirk for
HP Pavilion dv6).

In the commit message for the quirk this revert removes I wrote:

"Note that there are quite a few HP Pavilion dv6 variants, some
woth ATI and some with NVIDIA hybrid gfx, both seem to need this
quirk to have working backlight control. There are also some versions
with only Intel integrated gfx, these may not need this quirk, but it
should not hurt there."

Unfortunately that seems wrong, I've already received 2 reports of
this commit causing regressions on some dv6 variants (at least one
of which actually has a nvidia GPU). So it seems that HP has made a
mess here by using the same model-name both in marketing and in the
DMI data for many different variants. Some of which need
acpi_backlight=native for functional backlight control (as the
quirk this commit reverts was doing), where as others are broken by
it. So lets get back to the old sitation so as to avoid regressing
on models which used to work without any kernel cmdline arguments
before.

Fixes: 6276e53fa8c0 (ACPI / video: Add force_native quirk for HP Pavilion dv6)
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Revert commit 6276e53fa8c0 (ACPI / video: Add force_native quirk for
HP Pavilion dv6).

In the commit message for the quirk this revert removes I wrote:

"Note that there are quite a few HP Pavilion dv6 variants, some
woth ATI and some with NVIDIA hybrid gfx, both seem to need this
quirk to have working backlight control. There are also some versions
with only Intel integrated gfx, these may not need this quirk, but it
should not hurt there."

Unfortunately that seems wrong, I've already received 2 reports of
this commit causing regressions on some dv6 variants (at least one
of which actually has a nvidia GPU). So it seems that HP has made a
mess here by using the same model-name both in marketing and in the
DMI data for many different variants. Some of which need
acpi_backlight=native for functional backlight control (as the
quirk this commit reverts was doing), where as others are broken by
it. So lets get back to the old sitation so as to avoid regressing
on models which used to work without any kernel cmdline arguments
before.

Fixes: 6276e53fa8c0 (ACPI / video: Add force_native quirk for HP Pavilion dv6)
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Tables: Fix hidden logic related to acpi_tb_install_standard_table()</title>
<updated>2017-01-20T02:44:58+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2017-01-19T07:21:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7a37052adb5e843bcfff6c98aee9b60bb087b910'/>
<id>7a37052adb5e843bcfff6c98aee9b60bb087b910</id>
<content type='text'>
There is a hidden logic for acpi_tb_install_standard_table() as it can be
invoked from the boot stage and during runtime.

 1. When it is invoked from the OS boot stage, the ACPICA mutex may not have
    been initialized yet and so acpi_ut_acquire_mutex()/acpi_ut_release_mutex()
    are not invoked in these code paths:

   acpi_initialize_tables
     acpi_tb_parse_root_table
       acpi_tb_install_standard_table (4 invocations)
   acpi_install_table
       acpi_tb_install_standard_table

 2. When it is invoked during the runtime, ACPICA mutex is used as
    appropriate:

   acpi_ex_load_op
     acpi_tb_install_and_load_table
       acpi_tb_install_standard_table
   acpi_load_table
     acpi_tb_install_and_load_table
       acpi_tb_install_standard_table

The mutex is now used in acpi_tb_install_and_load_table(), while it actually
should be in acpi_tb_install_standard_table().

This introduces another problem in acpi_tb_install_standard_table() where
acpi_gbl_table_handler is invoked from and the lock contexts are thus not
consistent for the table handlers. This triggers a regression when
acpi_get_table()/acpi_put_table() start to hold table mutex during runtime.

The regression is noticed by LKP as new errors reported by ACPICA mutex
debugging facility.

[    2.043693] ACPI Error: Mutex [ACPI_MTX_Tables] already acquired by this thread [497483776] (20160930/utmutex-254)
[    2.054084] ACPI Error: Mutex [0x2] is not acquired, cannot release (20160930/utmutex-326)

And it triggers a deadlock:

[  247.066214] INFO: task swapper/0:1 blocked for more than 120 seconds.
...
[  247.091271] Call Trace:
...
[  247.121523]  down_timeout+0x47/0x50
[  247.125065]  acpi_os_wait_semaphore+0x47/0x62
[  247.129475]  acpi_ut_acquire_mutex+0x43/0x81
[  247.133798]  acpi_get_table+0x2d/0x84
[  247.137513]  acpi_table_attr_init+0xcd/0x100
[  247.146590]  acpi_sysfs_table_handler+0x5d/0xb8
[  247.151174]  acpi_bus_table_handler+0x23/0x2a
[  247.155583]  acpi_tb_install_standard_table+0xe0/0x213
[  247.164489]  acpi_tb_install_and_load_table+0x3a/0x82
[  247.169592]  acpi_ex_load_op+0x194/0x201
...
[  247.200108]  acpi_ns_evaluate+0x1bb/0x247
[  247.204170]  acpi_evaluate_object+0x178/0x274
[  247.213249]  acpi_processor_set_pdc+0x154/0x17b
...
The table mutex is held in acpi_tb_install_and_load_table() and is re-visited by
acpi_get_table().

Noticing that the early mutex requirement actually belongs to the OSL layer
and has already been handled in acpi_os_wait_semaphore()/acpi_os_signal_semaphore(),
the regression canbe fixed by removing this hidden logic from the ACPICA core
to the OS-specific code.

Fixes: 174cc7187e6f ("ACPICA: Tables: Back port acpi_get_table_with_size() and early_acpi_os_unmap_memory() from Linux kernel")
Reported-and-tested-by: Tomi Sarvela &lt;tomi.p.sarvela@intel.com&gt;
Reported-by: Ye Xiaolong &lt;xiaolong.ye@intel.com&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is a hidden logic for acpi_tb_install_standard_table() as it can be
invoked from the boot stage and during runtime.

 1. When it is invoked from the OS boot stage, the ACPICA mutex may not have
    been initialized yet and so acpi_ut_acquire_mutex()/acpi_ut_release_mutex()
    are not invoked in these code paths:

   acpi_initialize_tables
     acpi_tb_parse_root_table
       acpi_tb_install_standard_table (4 invocations)
   acpi_install_table
       acpi_tb_install_standard_table

 2. When it is invoked during the runtime, ACPICA mutex is used as
    appropriate:

   acpi_ex_load_op
     acpi_tb_install_and_load_table
       acpi_tb_install_standard_table
   acpi_load_table
     acpi_tb_install_and_load_table
       acpi_tb_install_standard_table

The mutex is now used in acpi_tb_install_and_load_table(), while it actually
should be in acpi_tb_install_standard_table().

This introduces another problem in acpi_tb_install_standard_table() where
acpi_gbl_table_handler is invoked from and the lock contexts are thus not
consistent for the table handlers. This triggers a regression when
acpi_get_table()/acpi_put_table() start to hold table mutex during runtime.

The regression is noticed by LKP as new errors reported by ACPICA mutex
debugging facility.

[    2.043693] ACPI Error: Mutex [ACPI_MTX_Tables] already acquired by this thread [497483776] (20160930/utmutex-254)
[    2.054084] ACPI Error: Mutex [0x2] is not acquired, cannot release (20160930/utmutex-326)

And it triggers a deadlock:

[  247.066214] INFO: task swapper/0:1 blocked for more than 120 seconds.
...
[  247.091271] Call Trace:
...
[  247.121523]  down_timeout+0x47/0x50
[  247.125065]  acpi_os_wait_semaphore+0x47/0x62
[  247.129475]  acpi_ut_acquire_mutex+0x43/0x81
[  247.133798]  acpi_get_table+0x2d/0x84
[  247.137513]  acpi_table_attr_init+0xcd/0x100
[  247.146590]  acpi_sysfs_table_handler+0x5d/0xb8
[  247.151174]  acpi_bus_table_handler+0x23/0x2a
[  247.155583]  acpi_tb_install_standard_table+0xe0/0x213
[  247.164489]  acpi_tb_install_and_load_table+0x3a/0x82
[  247.169592]  acpi_ex_load_op+0x194/0x201
...
[  247.200108]  acpi_ns_evaluate+0x1bb/0x247
[  247.204170]  acpi_evaluate_object+0x178/0x274
[  247.213249]  acpi_processor_set_pdc+0x154/0x17b
...
The table mutex is held in acpi_tb_install_and_load_table() and is re-visited by
acpi_get_table().

Noticing that the early mutex requirement actually belongs to the OSL layer
and has already been handled in acpi_os_wait_semaphore()/acpi_os_signal_semaphore(),
the regression canbe fixed by removing this hidden logic from the ACPICA core
to the OS-specific code.

Fixes: 174cc7187e6f ("ACPICA: Tables: Back port acpi_get_table_with_size() and early_acpi_os_unmap_memory() from Linux kernel")
Reported-and-tested-by: Tomi Sarvela &lt;tomi.p.sarvela@intel.com&gt;
Reported-by: Ye Xiaolong &lt;xiaolong.ye@intel.com&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag"</title>
<updated>2017-01-20T02:33:57+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2017-01-20T02:25:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e326ce013a8e851193eb337aafb1aa396c533a61'/>
<id>e326ce013a8e851193eb337aafb1aa396c533a61</id>
<content type='text'>
Revert commit 08b98d329165 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0
flag) as it caused system suspend (in the default configuration) to fail
on Dell XPS13 (9360) with the Kaby Lake processor.

Fixes: 08b98d329165 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag)
Reported-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Revert commit 08b98d329165 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0
flag) as it caused system suspend (in the default configuration) to fail
on Dell XPS13 (9360) with the Kaby Lake processor.

Fixes: 08b98d329165 (PM / sleep / ACPI: Use the ACPI_FADT_LOW_POWER_S0 flag)
Reported-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'acpi-scan', 'acpi-sysfs', 'acpi-wdat' and 'acpi-tables'</title>
<updated>2017-01-06T13:36:30+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2017-01-06T13:36:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f1dabf0b0975f9e71344b5c8c0ab39c4d58d9274'/>
<id>f1dabf0b0975f9e71344b5c8c0ab39c4d58d9274</id>
<content type='text'>
* acpi-scan:
  ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
  ACPI: Drop misplaced acpi_dma_deconfigure() call from acpi_bind_one()

* acpi-sysfs:
  ACPI / sysfs: Provide quirk mechanism to prevent GPE flooding

* acpi-wdat:
  ACPI / watchdog: Print out error number when device creation fails

* acpi-tables:
  ACPI / DMAR: Avoid passing NULL to acpi_put_table()
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* acpi-scan:
  ACPI / scan: Prefer devices without _HID/_CID for _ADR matching
  ACPI: Drop misplaced acpi_dma_deconfigure() call from acpi_bind_one()

* acpi-sysfs:
  ACPI / sysfs: Provide quirk mechanism to prevent GPE flooding

* acpi-wdat:
  ACPI / watchdog: Print out error number when device creation fails

* acpi-tables:
  ACPI / DMAR: Avoid passing NULL to acpi_put_table()
</pre>
</div>
</content>
</entry>
</feed>
