<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/acpi, branch v3.18.136</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ACPI: power: Skip duplicate power resource references in _PRx</title>
<updated>2019-01-26T08:44:24+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2018-12-30T17:25:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fe19dc973bbd10a4e710b316b358d95df32f8d8d'/>
<id>fe19dc973bbd10a4e710b316b358d95df32f8d8d</id>
<content type='text'>
commit 7d7b467cb95bf29597b417d4990160d4ea6d69b9 upstream.

Some ACPI tables contain duplicate power resource references like this:

        Name (_PR0, Package (0x04)  // _PR0: Power Resources for D0
        {
            P28P,
            P18P,
            P18P,
            CLK4
        })

This causes a WARN_ON in sysfs_add_link_to_group() because we end up
adding a link to the same acpi_device twice:

sysfs: cannot create duplicate filename '/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/808622C1:00/OVTI2680:00/power_resources_D0/LNXPOWER:0a'
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.12-301.fc29.x86_64 #1
Hardware name: Insyde CherryTrail/Type2 - Board Product Name, BIOS jumperx.T87.KFBNEEA02 04/13/2016
Call Trace:
 dump_stack+0x5c/0x80
 sysfs_warn_dup.cold.3+0x17/0x2a
 sysfs_do_create_link_sd.isra.2+0xa9/0xb0
 sysfs_add_link_to_group+0x30/0x50
 acpi_power_expose_list+0x74/0xa0
 acpi_power_add_remove_device+0x50/0xa0
 acpi_add_single_object+0x26b/0x5f0
 acpi_bus_check_add+0xc4/0x250
 ...

To address this issue, make acpi_extract_power_resources() check for
duplicates and simply skip them when found.

Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
[ rjw: Subject &amp; changelog, comments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@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 7d7b467cb95bf29597b417d4990160d4ea6d69b9 upstream.

Some ACPI tables contain duplicate power resource references like this:

        Name (_PR0, Package (0x04)  // _PR0: Power Resources for D0
        {
            P28P,
            P18P,
            P18P,
            CLK4
        })

This causes a WARN_ON in sysfs_add_link_to_group() because we end up
adding a link to the same acpi_device twice:

sysfs: cannot create duplicate filename '/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/808622C1:00/OVTI2680:00/power_resources_D0/LNXPOWER:0a'
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.12-301.fc29.x86_64 #1
Hardware name: Insyde CherryTrail/Type2 - Board Product Name, BIOS jumperx.T87.KFBNEEA02 04/13/2016
Call Trace:
 dump_stack+0x5c/0x80
 sysfs_warn_dup.cold.3+0x17/0x2a
 sysfs_do_create_link_sd.isra.2+0xa9/0xb0
 sysfs_add_link_to_group+0x30/0x50
 acpi_power_expose_list+0x74/0xa0
 acpi_power_add_remove_device+0x50/0xa0
 acpi_add_single_object+0x26b/0x5f0
 acpi_bus_check_add+0xc4/0x250
 ...

To address this issue, make acpi_extract_power_resources() check for
duplicates and simply skip them when found.

Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
[ rjw: Subject &amp; changelog, comments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI / platform: Add SMB0001 HID to forbidden_id_list</title>
<updated>2018-11-27T15:05:37+00:00</updated>
<author>
<name>Hans de Goede</name>
<email>hdegoede@redhat.com</email>
</author>
<published>2018-11-19T18:06:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4c235447701f24884b55f38d771ca2ae643a135f'/>
<id>4c235447701f24884b55f38d771ca2ae643a135f</id>
<content type='text'>
commit 2bbb5fa37475d7aa5fa62f34db1623f3da2dfdfa upstream.

Many HP AMD based laptops contain an SMB0001 device like this:

Device (SMBD)
{
    Name (_HID, "SMB0001")  // _HID: Hardware ID
    Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
    {
        IO (Decode16,
            0x0B20,             // Range Minimum
            0x0B20,             // Range Maximum
            0x20,               // Alignment
            0x20,               // Length
            )
        IRQ (Level, ActiveLow, Shared, )
            {7}
    })
}

The legacy style IRQ resource here causes acpi_dev_get_irqresource() to
be called with legacy=true and this message to show in dmesg:
ACPI: IRQ 7 override to edge, high

This causes issues when later on the AMD0030 GPIO device gets enumerated:

Device (GPIO)
{
    Name (_HID, "AMDI0030")  // _HID: Hardware ID
    Name (_CID, "AMDI0030")  // _CID: Compatible ID
    Name (_UID, Zero)  // _UID: Unique ID
    Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
    {
	Name (RBUF, ResourceTemplate ()
	{
	    Interrupt (ResourceConsumer, Level, ActiveLow, Shared, ,, )
	    {
		0x00000007,
	    }
	    Memory32Fixed (ReadWrite,
		0xFED81500,         // Address Base
		0x00000400,         // Address Length
		)
	})
	Return (RBUF) /* \_SB_.GPIO._CRS.RBUF */
    }
}

Now acpi_dev_get_irqresource() gets called with legacy=false, but because
of the earlier override of the trigger-type acpi_register_gsi() returns
-EBUSY (because we try to register the same interrupt with a different
trigger-type) and we end up setting IORESOURCE_DISABLED in the flags.

The setting of IORESOURCE_DISABLED causes platform_get_irq() to call
acpi_irq_get() which is not implemented on x86 and returns -EINVAL.
resulting in the following in dmesg:

amd_gpio AMDI0030:00: Failed to get gpio IRQ: -22
amd_gpio: probe of AMDI0030:00 failed with error -22

The SMB0001 is a "virtual" device in the sense that the only way the OS
interacts with it is through calling a couple of methods to do SMBus
transfers. As such it is weird that it has IO and IRQ resources at all,
because the driver for it is not expected to ever access the hardware
directly.

The Linux driver for the SMB0001 device directly binds to the acpi_device
through the acpi_bus, so we do not need to instantiate a platform_device
for this ACPI device. This commit adds the SMB0001 HID to the
forbidden_id_list, avoiding the instantiating of a platform_device for it.
Not instantiating a platform_device means we will no longer call
acpi_dev_get_irqresource() for the legacy IRQ resource fixing the probe of
the AMDI0030 device failing.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1644013
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198715
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199523
Reported-by: Lukas Kahnert &lt;openproggerfreak@gmail.com&gt;
Tested-by: Marc &lt;suaefar@googlemail.com&gt;
Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@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 2bbb5fa37475d7aa5fa62f34db1623f3da2dfdfa upstream.

Many HP AMD based laptops contain an SMB0001 device like this:

Device (SMBD)
{
    Name (_HID, "SMB0001")  // _HID: Hardware ID
    Name (_CRS, ResourceTemplate ()  // _CRS: Current Resource Settings
    {
        IO (Decode16,
            0x0B20,             // Range Minimum
            0x0B20,             // Range Maximum
            0x20,               // Alignment
            0x20,               // Length
            )
        IRQ (Level, ActiveLow, Shared, )
            {7}
    })
}

The legacy style IRQ resource here causes acpi_dev_get_irqresource() to
be called with legacy=true and this message to show in dmesg:
ACPI: IRQ 7 override to edge, high

This causes issues when later on the AMD0030 GPIO device gets enumerated:

Device (GPIO)
{
    Name (_HID, "AMDI0030")  // _HID: Hardware ID
    Name (_CID, "AMDI0030")  // _CID: Compatible ID
    Name (_UID, Zero)  // _UID: Unique ID
    Method (_CRS, 0, NotSerialized)  // _CRS: Current Resource Settings
    {
	Name (RBUF, ResourceTemplate ()
	{
	    Interrupt (ResourceConsumer, Level, ActiveLow, Shared, ,, )
	    {
		0x00000007,
	    }
	    Memory32Fixed (ReadWrite,
		0xFED81500,         // Address Base
		0x00000400,         // Address Length
		)
	})
	Return (RBUF) /* \_SB_.GPIO._CRS.RBUF */
    }
}

Now acpi_dev_get_irqresource() gets called with legacy=false, but because
of the earlier override of the trigger-type acpi_register_gsi() returns
-EBUSY (because we try to register the same interrupt with a different
trigger-type) and we end up setting IORESOURCE_DISABLED in the flags.

The setting of IORESOURCE_DISABLED causes platform_get_irq() to call
acpi_irq_get() which is not implemented on x86 and returns -EINVAL.
resulting in the following in dmesg:

amd_gpio AMDI0030:00: Failed to get gpio IRQ: -22
amd_gpio: probe of AMDI0030:00 failed with error -22

The SMB0001 is a "virtual" device in the sense that the only way the OS
interacts with it is through calling a couple of methods to do SMBus
transfers. As such it is weird that it has IO and IRQ resources at all,
because the driver for it is not expected to ever access the hardware
directly.

The Linux driver for the SMB0001 device directly binds to the acpi_device
through the acpi_bus, so we do not need to instantiate a platform_device
for this ACPI device. This commit adds the SMB0001 HID to the
forbidden_id_list, avoiding the instantiating of a platform_device for it.
Not instantiating a platform_device means we will no longer call
acpi_dev_get_irqresource() for the legacy IRQ resource fixing the probe of
the AMDI0030 device failing.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1644013
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=198715
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=199523
Reported-by: Lukas Kahnert &lt;openproggerfreak@gmail.com&gt;
Tested-by: Marc &lt;suaefar@googlemail.com&gt;
Cc: All applicable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Hans de Goede &lt;hdegoede@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>PCI: pciehp: Request control of native hotplug only if supported</title>
<updated>2018-08-09T10:20:28+00:00</updated>
<author>
<name>Mika Westerberg</name>
<email>mika.westerberg@linux.intel.com</email>
</author>
<published>2018-05-23T22:19:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6af19d06df562a5393e8d5a2c6d5b7739caf313e'/>
<id>6af19d06df562a5393e8d5a2c6d5b7739caf313e</id>
<content type='text'>
[ Upstream commit 408fec36a1ab3d14273c2116b449ef1e9be3cb8b ]

Currently we request control of native PCIe hotplug unconditionally.
Native PCIe hotplug events are handled by the pciehp driver, and if it is
not enabled those events will be lost.

Request control of native PCIe hotplug only if the pciehp driver is
enabled, so we will actually handle native PCIe hotplug events.

Suggested-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit 408fec36a1ab3d14273c2116b449ef1e9be3cb8b ]

Currently we request control of native PCIe hotplug unconditionally.
Native PCIe hotplug events are handled by the pciehp driver, and if it is
not enabled those events will be lost.

Request control of native PCIe hotplug only if the pciehp driver is
enabled, so we will actually handle native PCIe hotplug events.

Suggested-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Signed-off-by: Mika Westerberg &lt;mika.westerberg@linux.intel.com&gt;
Signed-off-by: Bjorn Helgaas &lt;bhelgaas@google.com&gt;
Reviewed-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: acpi: acpica: fix acpi operand cache leak in nseval.c</title>
<updated>2018-05-30T05:47:41+00:00</updated>
<author>
<name>Seunghun Han</name>
<email>kkamagui@gmail.com</email>
</author>
<published>2018-03-14T23:12:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c81492260a2202dcea658087b5dd1b319f59bbf0'/>
<id>c81492260a2202dcea658087b5dd1b319f59bbf0</id>
<content type='text'>
[ Upstream commit 97f3c0a4b0579b646b6b10ae5a3d59f0441cc12c ]

I found an ACPI cache leak in ACPI early termination and boot continuing case.

When early termination occurs due to malicious ACPI table, Linux kernel
terminates ACPI function and continues to boot process. While kernel terminates
ACPI function, kmem_cache_destroy() reports Acpi-Operand cache leak.

Boot log of ACPI operand cache leak is as follows:
&gt;[    0.464168] ACPI: Added _OSI(Module Device)
&gt;[    0.467022] ACPI: Added _OSI(Processor Device)
&gt;[    0.469376] ACPI: Added _OSI(3.0 _SCP Extensions)
&gt;[    0.471647] ACPI: Added _OSI(Processor Aggregator Device)
&gt;[    0.477997] ACPI Error: Null stack entry at ffff880215c0aad8 (20170303/exresop-174)
&gt;[    0.482706] ACPI Exception: AE_AML_INTERNAL, While resolving operands for [opcode_name unavailable] (20170303/dswexec-461)
&gt;[    0.487503] ACPI Error: Method parse/execution failed [\DBG] (Node ffff88021710ab40), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.492136] ACPI Error: Method parse/execution failed [\_SB._INI] (Node ffff88021710a618), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.497683] ACPI: Interpreter enabled
&gt;[    0.499385] ACPI: (supports S0)
&gt;[    0.501151] ACPI: Using IOAPIC for interrupt routing
&gt;[    0.503342] ACPI Error: Null stack entry at ffff880215c0aad8 (20170303/exresop-174)
&gt;[    0.506522] ACPI Exception: AE_AML_INTERNAL, While resolving operands for [opcode_name unavailable] (20170303/dswexec-461)
&gt;[    0.510463] ACPI Error: Method parse/execution failed [\DBG] (Node ffff88021710ab40), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.514477] ACPI Error: Method parse/execution failed [\_PIC] (Node ffff88021710ab18), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.518867] ACPI Exception: AE_AML_INTERNAL, Evaluating _PIC (20170303/bus-991)
&gt;[    0.522384] kmem_cache_destroy Acpi-Operand: Slab cache still has objects
&gt;[    0.524597] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc5 #26
&gt;[    0.526795] Hardware name: innotek gmb_h virtual_box/virtual_box, BIOS virtual_box 12/01/2006
&gt;[    0.529668] Call Trace:
&gt;[    0.530811]  ? dump_stack+0x5c/0x81
&gt;[    0.532240]  ? kmem_cache_destroy+0x1aa/0x1c0
&gt;[    0.533905]  ? acpi_os_delete_cache+0xa/0x10
&gt;[    0.535497]  ? acpi_ut_delete_caches+0x3f/0x7b
&gt;[    0.537237]  ? acpi_terminate+0xa/0x14
&gt;[    0.538701]  ? acpi_init+0x2af/0x34f
&gt;[    0.540008]  ? acpi_sleep_proc_init+0x27/0x27
&gt;[    0.541593]  ? do_one_initcall+0x4e/0x1a0
&gt;[    0.543008]  ? kernel_init_freeable+0x19e/0x21f
&gt;[    0.546202]  ? rest_init+0x80/0x80
&gt;[    0.547513]  ? kernel_init+0xa/0x100
&gt;[    0.548817]  ? ret_from_fork+0x25/0x30
&gt;[    0.550587] vgaarb: loaded
&gt;[    0.551716] EDAC MC: Ver: 3.0.0
&gt;[    0.553744] PCI: Probing PCI hardware
&gt;[    0.555038] PCI host bridge to bus 0000:00
&gt; ... Continue to boot and log is omitted ...

I analyzed this memory leak in detail and found acpi_ns_evaluate() function
only removes Info-&gt;return_object in AE_CTRL_RETURN_VALUE case. But, when errors
occur, the status value is not AE_CTRL_RETURN_VALUE, and Info-&gt;return_object is
also not null. Therefore, this causes acpi operand memory leak.

This cache leak causes a security threat because an old kernel (&lt;= 4.9) shows
memory locations of kernel functions in stack dump. Some malicious users
could use this information to neutralize kernel ASLR.

I made a patch to fix ACPI operand cache leak.

Signed-off-by: Seunghun Han &lt;kkamagui@gmail.com&gt;
Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit 97f3c0a4b0579b646b6b10ae5a3d59f0441cc12c ]

I found an ACPI cache leak in ACPI early termination and boot continuing case.

When early termination occurs due to malicious ACPI table, Linux kernel
terminates ACPI function and continues to boot process. While kernel terminates
ACPI function, kmem_cache_destroy() reports Acpi-Operand cache leak.

Boot log of ACPI operand cache leak is as follows:
&gt;[    0.464168] ACPI: Added _OSI(Module Device)
&gt;[    0.467022] ACPI: Added _OSI(Processor Device)
&gt;[    0.469376] ACPI: Added _OSI(3.0 _SCP Extensions)
&gt;[    0.471647] ACPI: Added _OSI(Processor Aggregator Device)
&gt;[    0.477997] ACPI Error: Null stack entry at ffff880215c0aad8 (20170303/exresop-174)
&gt;[    0.482706] ACPI Exception: AE_AML_INTERNAL, While resolving operands for [opcode_name unavailable] (20170303/dswexec-461)
&gt;[    0.487503] ACPI Error: Method parse/execution failed [\DBG] (Node ffff88021710ab40), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.492136] ACPI Error: Method parse/execution failed [\_SB._INI] (Node ffff88021710a618), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.497683] ACPI: Interpreter enabled
&gt;[    0.499385] ACPI: (supports S0)
&gt;[    0.501151] ACPI: Using IOAPIC for interrupt routing
&gt;[    0.503342] ACPI Error: Null stack entry at ffff880215c0aad8 (20170303/exresop-174)
&gt;[    0.506522] ACPI Exception: AE_AML_INTERNAL, While resolving operands for [opcode_name unavailable] (20170303/dswexec-461)
&gt;[    0.510463] ACPI Error: Method parse/execution failed [\DBG] (Node ffff88021710ab40), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.514477] ACPI Error: Method parse/execution failed [\_PIC] (Node ffff88021710ab18), AE_AML_INTERNAL (20170303/psparse-543)
&gt;[    0.518867] ACPI Exception: AE_AML_INTERNAL, Evaluating _PIC (20170303/bus-991)
&gt;[    0.522384] kmem_cache_destroy Acpi-Operand: Slab cache still has objects
&gt;[    0.524597] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.12.0-rc5 #26
&gt;[    0.526795] Hardware name: innotek gmb_h virtual_box/virtual_box, BIOS virtual_box 12/01/2006
&gt;[    0.529668] Call Trace:
&gt;[    0.530811]  ? dump_stack+0x5c/0x81
&gt;[    0.532240]  ? kmem_cache_destroy+0x1aa/0x1c0
&gt;[    0.533905]  ? acpi_os_delete_cache+0xa/0x10
&gt;[    0.535497]  ? acpi_ut_delete_caches+0x3f/0x7b
&gt;[    0.537237]  ? acpi_terminate+0xa/0x14
&gt;[    0.538701]  ? acpi_init+0x2af/0x34f
&gt;[    0.540008]  ? acpi_sleep_proc_init+0x27/0x27
&gt;[    0.541593]  ? do_one_initcall+0x4e/0x1a0
&gt;[    0.543008]  ? kernel_init_freeable+0x19e/0x21f
&gt;[    0.546202]  ? rest_init+0x80/0x80
&gt;[    0.547513]  ? kernel_init+0xa/0x100
&gt;[    0.548817]  ? ret_from_fork+0x25/0x30
&gt;[    0.550587] vgaarb: loaded
&gt;[    0.551716] EDAC MC: Ver: 3.0.0
&gt;[    0.553744] PCI: Probing PCI hardware
&gt;[    0.555038] PCI host bridge to bus 0000:00
&gt; ... Continue to boot and log is omitted ...

I analyzed this memory leak in detail and found acpi_ns_evaluate() function
only removes Info-&gt;return_object in AE_CTRL_RETURN_VALUE case. But, when errors
occur, the status value is not AE_CTRL_RETURN_VALUE, and Info-&gt;return_object is
also not null. Therefore, this causes acpi operand memory leak.

This cache leak causes a security threat because an old kernel (&lt;= 4.9) shows
memory locations of kernel functions in stack dump. Some malicious users
could use this information to neutralize kernel ASLR.

I made a patch to fix ACPI operand cache leak.

Signed-off-by: Seunghun Han &lt;kkamagui@gmail.com&gt;
Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Events: add a return on failure from acpi_hw_register_read</title>
<updated>2018-05-30T05:47:41+00:00</updated>
<author>
<name>Erik Schmauss</name>
<email>erik.schmauss@intel.com</email>
</author>
<published>2018-03-14T23:13:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=43f9785ba5eb5100f879cdcfd7bb5dccd6057d2d'/>
<id>43f9785ba5eb5100f879cdcfd7bb5dccd6057d2d</id>
<content type='text'>
[ Upstream commit b4c0de312613ca676db5bd7e696a44b56795612a ]

This ensures that acpi_ev_fixed_event_detect() does not use fixed_status
and and fixed_enable as uninitialized variables.

Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit b4c0de312613ca676db5bd7e696a44b56795612a ]

This ensures that acpi_ev_fixed_event_detect() does not use fixed_status
and and fixed_enable as uninitialized variables.

Signed-off-by: Erik Schmauss &lt;erik.schmauss@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: acpi_pad: Fix memory leak in power saving threads</title>
<updated>2018-05-30T05:47:40+00:00</updated>
<author>
<name>Lenny Szubowicz</name>
<email>lszubowi@redhat.com</email>
</author>
<published>2018-03-27T13:56:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c893df8b44bb2c18f6875c918f3d3b778c195fe3'/>
<id>c893df8b44bb2c18f6875c918f3d3b778c195fe3</id>
<content type='text'>
[ Upstream commit 8b29d29abc484d638213dd79a18a95ae7e5bb402 ]

Fix once per second (round_robin_time) memory leak of about 1 KB in
each acpi_pad kernel idling thread that is activated.

Found by testing with kmemleak.

Signed-off-by: Lenny Szubowicz &lt;lszubowi@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit 8b29d29abc484d638213dd79a18a95ae7e5bb402 ]

Fix once per second (round_robin_time) memory leak of about 1 KB in
each acpi_pad kernel idling thread that is activated.

Found by testing with kmemleak.

Signed-off-by: Lenny Szubowicz &lt;lszubowi@redhat.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI: processor_perflib: Do not send _PPC change notification if not ready</title>
<updated>2018-05-30T05:47:32+00:00</updated>
<author>
<name>Chen Yu</name>
<email>yu.c.chen@intel.com</email>
</author>
<published>2018-01-29T02:26:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4c53640915f20c4372239348d89d4338b55da2f4'/>
<id>4c53640915f20c4372239348d89d4338b55da2f4</id>
<content type='text'>
[ Upstream commit ba1edb9a5125a617d612f98eead14b9b84e75c3a ]

The following warning was triggered after resumed from S3 -
if all the nonboot CPUs were put offline before suspend:

[ 1840.329515] unchecked MSR access error: RDMSR from 0x771 at rIP: 0xffffffff86061e3a (native_read_msr+0xa/0x30)
[ 1840.329516] Call Trace:
[ 1840.329521]  __rdmsr_on_cpu+0x33/0x50
[ 1840.329525]  generic_exec_single+0x81/0xb0
[ 1840.329527]  smp_call_function_single+0xd2/0x100
[ 1840.329530]  ? acpi_ds_result_pop+0xdd/0xf2
[ 1840.329532]  ? acpi_ds_create_operand+0x215/0x23c
[ 1840.329534]  rdmsrl_on_cpu+0x57/0x80
[ 1840.329536]  ? cpumask_next+0x1b/0x20
[ 1840.329538]  ? rdmsrl_on_cpu+0x57/0x80
[ 1840.329541]  intel_pstate_update_perf_limits+0xf3/0x220
[ 1840.329544]  ? notifier_call_chain+0x4a/0x70
[ 1840.329546]  intel_pstate_set_policy+0x4e/0x150
[ 1840.329548]  cpufreq_set_policy+0xcd/0x2f0
[ 1840.329550]  cpufreq_update_policy+0xb2/0x130
[ 1840.329552]  ? cpufreq_update_policy+0x130/0x130
[ 1840.329556]  acpi_processor_ppc_has_changed+0x65/0x80
[ 1840.329558]  acpi_processor_notify+0x80/0x100
[ 1840.329561]  acpi_ev_notify_dispatch+0x44/0x5c
[ 1840.329563]  acpi_os_execute_deferred+0x14/0x20
[ 1840.329565]  process_one_work+0x193/0x3c0
[ 1840.329567]  worker_thread+0x35/0x3b0
[ 1840.329569]  kthread+0x125/0x140
[ 1840.329571]  ? process_one_work+0x3c0/0x3c0
[ 1840.329572]  ? kthread_park+0x60/0x60
[ 1840.329575]  ? do_syscall_64+0x67/0x180
[ 1840.329577]  ret_from_fork+0x25/0x30
[ 1840.329585] unchecked MSR access error: WRMSR to 0x774 (tried to write 0x0000000000000000) at rIP: 0xffffffff86061f78 (native_write_msr+0x8/0x30)
[ 1840.329586] Call Trace:
[ 1840.329587]  __wrmsr_on_cpu+0x37/0x40
[ 1840.329589]  generic_exec_single+0x81/0xb0
[ 1840.329592]  smp_call_function_single+0xd2/0x100
[ 1840.329594]  ? acpi_ds_create_operand+0x215/0x23c
[ 1840.329595]  ? cpumask_next+0x1b/0x20
[ 1840.329597]  wrmsrl_on_cpu+0x57/0x70
[ 1840.329598]  ? rdmsrl_on_cpu+0x57/0x80
[ 1840.329599]  ? wrmsrl_on_cpu+0x57/0x70
[ 1840.329602]  intel_pstate_hwp_set+0xd3/0x150
[ 1840.329604]  intel_pstate_set_policy+0x119/0x150
[ 1840.329606]  cpufreq_set_policy+0xcd/0x2f0
[ 1840.329607]  cpufreq_update_policy+0xb2/0x130
[ 1840.329610]  ? cpufreq_update_policy+0x130/0x130
[ 1840.329613]  acpi_processor_ppc_has_changed+0x65/0x80
[ 1840.329615]  acpi_processor_notify+0x80/0x100
[ 1840.329617]  acpi_ev_notify_dispatch+0x44/0x5c
[ 1840.329619]  acpi_os_execute_deferred+0x14/0x20
[ 1840.329620]  process_one_work+0x193/0x3c0
[ 1840.329622]  worker_thread+0x35/0x3b0
[ 1840.329624]  kthread+0x125/0x140
[ 1840.329625]  ? process_one_work+0x3c0/0x3c0
[ 1840.329626]  ? kthread_park+0x60/0x60
[ 1840.329628]  ? do_syscall_64+0x67/0x180
[ 1840.329631]  ret_from_fork+0x25/0x30

This is because if there's only one online CPU, the MSR_PM_ENABLE
(package wide)can not be enabled after resumed, due to
intel_pstate_hwp_enable() will only be invoked on AP's online
process after resumed - if there's no AP online, the HWP remains
disabled after resumed (BIOS has disabled it in S3). Then if
there comes a _PPC change notification which touches HWP register
during this stage, the warning is triggered.

Since we don't call acpi_processor_register_performance() when
HWP is enabled, the pr-&gt;performance will be NULL. When this is
NULL we don't need to do _PPC change notification.

Reported-by: Doug Smythies &lt;dsmythies@telus.net&gt;
Suggested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Yu Chen &lt;yu.c.chen@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit ba1edb9a5125a617d612f98eead14b9b84e75c3a ]

The following warning was triggered after resumed from S3 -
if all the nonboot CPUs were put offline before suspend:

[ 1840.329515] unchecked MSR access error: RDMSR from 0x771 at rIP: 0xffffffff86061e3a (native_read_msr+0xa/0x30)
[ 1840.329516] Call Trace:
[ 1840.329521]  __rdmsr_on_cpu+0x33/0x50
[ 1840.329525]  generic_exec_single+0x81/0xb0
[ 1840.329527]  smp_call_function_single+0xd2/0x100
[ 1840.329530]  ? acpi_ds_result_pop+0xdd/0xf2
[ 1840.329532]  ? acpi_ds_create_operand+0x215/0x23c
[ 1840.329534]  rdmsrl_on_cpu+0x57/0x80
[ 1840.329536]  ? cpumask_next+0x1b/0x20
[ 1840.329538]  ? rdmsrl_on_cpu+0x57/0x80
[ 1840.329541]  intel_pstate_update_perf_limits+0xf3/0x220
[ 1840.329544]  ? notifier_call_chain+0x4a/0x70
[ 1840.329546]  intel_pstate_set_policy+0x4e/0x150
[ 1840.329548]  cpufreq_set_policy+0xcd/0x2f0
[ 1840.329550]  cpufreq_update_policy+0xb2/0x130
[ 1840.329552]  ? cpufreq_update_policy+0x130/0x130
[ 1840.329556]  acpi_processor_ppc_has_changed+0x65/0x80
[ 1840.329558]  acpi_processor_notify+0x80/0x100
[ 1840.329561]  acpi_ev_notify_dispatch+0x44/0x5c
[ 1840.329563]  acpi_os_execute_deferred+0x14/0x20
[ 1840.329565]  process_one_work+0x193/0x3c0
[ 1840.329567]  worker_thread+0x35/0x3b0
[ 1840.329569]  kthread+0x125/0x140
[ 1840.329571]  ? process_one_work+0x3c0/0x3c0
[ 1840.329572]  ? kthread_park+0x60/0x60
[ 1840.329575]  ? do_syscall_64+0x67/0x180
[ 1840.329577]  ret_from_fork+0x25/0x30
[ 1840.329585] unchecked MSR access error: WRMSR to 0x774 (tried to write 0x0000000000000000) at rIP: 0xffffffff86061f78 (native_write_msr+0x8/0x30)
[ 1840.329586] Call Trace:
[ 1840.329587]  __wrmsr_on_cpu+0x37/0x40
[ 1840.329589]  generic_exec_single+0x81/0xb0
[ 1840.329592]  smp_call_function_single+0xd2/0x100
[ 1840.329594]  ? acpi_ds_create_operand+0x215/0x23c
[ 1840.329595]  ? cpumask_next+0x1b/0x20
[ 1840.329597]  wrmsrl_on_cpu+0x57/0x70
[ 1840.329598]  ? rdmsrl_on_cpu+0x57/0x80
[ 1840.329599]  ? wrmsrl_on_cpu+0x57/0x70
[ 1840.329602]  intel_pstate_hwp_set+0xd3/0x150
[ 1840.329604]  intel_pstate_set_policy+0x119/0x150
[ 1840.329606]  cpufreq_set_policy+0xcd/0x2f0
[ 1840.329607]  cpufreq_update_policy+0xb2/0x130
[ 1840.329610]  ? cpufreq_update_policy+0x130/0x130
[ 1840.329613]  acpi_processor_ppc_has_changed+0x65/0x80
[ 1840.329615]  acpi_processor_notify+0x80/0x100
[ 1840.329617]  acpi_ev_notify_dispatch+0x44/0x5c
[ 1840.329619]  acpi_os_execute_deferred+0x14/0x20
[ 1840.329620]  process_one_work+0x193/0x3c0
[ 1840.329622]  worker_thread+0x35/0x3b0
[ 1840.329624]  kthread+0x125/0x140
[ 1840.329625]  ? process_one_work+0x3c0/0x3c0
[ 1840.329626]  ? kthread_park+0x60/0x60
[ 1840.329628]  ? do_syscall_64+0x67/0x180
[ 1840.329631]  ret_from_fork+0x25/0x30

This is because if there's only one online CPU, the MSR_PM_ENABLE
(package wide)can not be enabled after resumed, due to
intel_pstate_hwp_enable() will only be invoked on AP's online
process after resumed - if there's no AP online, the HWP remains
disabled after resumed (BIOS has disabled it in S3). Then if
there comes a _PPC change notification which touches HWP register
during this stage, the warning is triggered.

Since we don't call acpi_processor_register_performance() when
HWP is enabled, the pr-&gt;performance will be NULL. When this is
NULL we don't need to do _PPC change notification.

Reported-by: Doug Smythies &lt;dsmythies@telus.net&gt;
Suggested-by: Srinivas Pandruvada &lt;srinivas.pandruvada@linux.intel.com&gt;
Signed-off-by: Yu Chen &lt;yu.c.chen@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Disassembler: Abort on an invalid/unknown AML opcode</title>
<updated>2018-04-13T17:52:21+00:00</updated>
<author>
<name>Bob Moore</name>
<email>robert.moore@intel.com</email>
</author>
<published>2017-06-05T08:40:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b51f16e3172b61434cf7e818a223318dc185f40c'/>
<id>b51f16e3172b61434cf7e818a223318dc185f40c</id>
<content type='text'>
[ Upstream commit 6f0527b77d9e0129dd8e50945b0d610ed943d6b2 ]

ACPICA commit ed0389cb11a61e63c568ac1f67948fc6a7bd1aeb

An invalid opcode indicates something seriously wrong with the
input AML file. The AML parser is immediately confused and lost,
causing the resulting parse tree to be ill-formed. The actual
disassembly can then cause numerous unrelated errors and faults.

This change aborts the disassembly upon discovery of such an
opcode during the AML parse phase.

Link: https://github.com/acpica/acpica/commit/ed0389cb
Signed-off-by: Bob Moore &lt;robert.moore@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;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit 6f0527b77d9e0129dd8e50945b0d610ed943d6b2 ]

ACPICA commit ed0389cb11a61e63c568ac1f67948fc6a7bd1aeb

An invalid opcode indicates something seriously wrong with the
input AML file. The AML parser is immediately confused and lost,
causing the resulting parse tree to be ill-formed. The actual
disassembly can then cause numerous unrelated errors and faults.

This change aborts the disassembly upon discovery of such an
opcode during the AML parse phase.

Link: https://github.com/acpica/acpica/commit/ed0389cb
Signed-off-by: Bob Moore &lt;robert.moore@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;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPICA: Events: Add runtime stub support for event APIs</title>
<updated>2018-04-13T17:52:21+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2017-06-05T08:40:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=525e1c229280d8f1b983339a06824e18961d1cc2'/>
<id>525e1c229280d8f1b983339a06824e18961d1cc2</id>
<content type='text'>
[ Upstream commit 861ba6351c520328e94a78c923b415faa9116287 ]

ACPICA commit 99bc3beca92c6574ea1d69de42e54f872e6373ce

It is reported that on Linux, RTC driver complains wrong errors on
hardware reduced platform:
  [    4.085420] ACPI Warning: Could not enable fixed event - real_time_clock (4) (20160422/evxface-654)

This patch fixes this by correctly adding runtime reduced hardware check.
Reported by Chandan Tagore, fixed by Lv Zheng.

Link: https://github.com/acpica/acpica/commit/99bc3bec
Tested-by: Chandan Tagore &lt;tagore.chandan@gmail.com&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.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>
[ Upstream commit 861ba6351c520328e94a78c923b415faa9116287 ]

ACPICA commit 99bc3beca92c6574ea1d69de42e54f872e6373ce

It is reported that on Linux, RTC driver complains wrong errors on
hardware reduced platform:
  [    4.085420] ACPI Warning: Could not enable fixed event - real_time_clock (4) (20160422/evxface-654)

This patch fixes this by correctly adding runtime reduced hardware check.
Reported by Chandan Tagore, fixed by Lv Zheng.

Link: https://github.com/acpica/acpica/commit/99bc3bec
Tested-by: Chandan Tagore &lt;tagore.chandan@gmail.com&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Bob Moore &lt;robert.moore@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ACPI/processor: Replace racy task affinity logic</title>
<updated>2018-03-24T09:57:32+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2017-04-12T20:07:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2d2cfeb58d8c120a95150006bc39063db2b7ac54'/>
<id>2d2cfeb58d8c120a95150006bc39063db2b7ac54</id>
<content type='text'>
[ Upstream commit 8153f9ac43897f9f4786b30badc134fcc1a4fb11 ]

acpi_processor_get_throttling() requires to invoke the getter function on
the target CPU. This is achieved by temporarily setting the affinity of the
calling user space thread to the requested CPU and reset it to the original
affinity afterwards.

That's racy vs. CPU hotplug and concurrent affinity settings for that
thread resulting in code executing on the wrong CPU and overwriting the
new affinity setting.

acpi_processor_get_throttling() is invoked in two ways:

1) The CPU online callback, which is already running on the target CPU and
   obviously protected against hotplug and not affected by affinity
   settings.

2) The ACPI driver probe function, which is not protected against hotplug
   during modprobe.

Switch it over to work_on_cpu() and protect the probe function against CPU
hotplug.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Lai Jiangshan &lt;jiangshanlai@gmail.com&gt;
Cc: linux-acpi@vger.kernel.org
Cc: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Len Brown &lt;lenb@kernel.org&gt;
Link: http://lkml.kernel.org/r/20170412201042.785920903@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
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[ Upstream commit 8153f9ac43897f9f4786b30badc134fcc1a4fb11 ]

acpi_processor_get_throttling() requires to invoke the getter function on
the target CPU. This is achieved by temporarily setting the affinity of the
calling user space thread to the requested CPU and reset it to the original
affinity afterwards.

That's racy vs. CPU hotplug and concurrent affinity settings for that
thread resulting in code executing on the wrong CPU and overwriting the
new affinity setting.

acpi_processor_get_throttling() is invoked in two ways:

1) The CPU online callback, which is already running on the target CPU and
   obviously protected against hotplug and not affected by affinity
   settings.

2) The ACPI driver probe function, which is not protected against hotplug
   during modprobe.

Switch it over to work_on_cpu() and protect the probe function against CPU
hotplug.

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Fenghua Yu &lt;fenghua.yu@intel.com&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: "Rafael J. Wysocki" &lt;rjw@rjwysocki.net&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Lai Jiangshan &lt;jiangshanlai@gmail.com&gt;
Cc: linux-acpi@vger.kernel.org
Cc: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: "David S. Miller" &lt;davem@davemloft.net&gt;
Cc: Len Brown &lt;lenb@kernel.org&gt;
Link: http://lkml.kernel.org/r/20170412201042.785920903@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Sasha Levin &lt;alexander.levin@microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
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