x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPU

For non-eager fpu mode, thread's fpu state is allocated during the first
fpu usage (in the context of device not available exception). This
(math_state_restore()) can be a blocking call and hence we enable
interrupts (which were originally disabled when the exception happened),
allocate memory and disable interrupts etc.

But the eager-fpu mode, call's the same math_state_restore() from
kernel_fpu_end(). The assumption being that tsk_used_math() is always
set for the eager-fpu mode and thus avoid the code path of enabling
interrupts, allocating fpu state using blocking call and disable
interrupts etc.

But the below issue was noticed by Maarten Baert, Nate Eldredge and
few others:

If a user process dumps core on an ecrypt fs while aesni-intel is loaded,
we get a BUG() in __find_get_block() complaining that it was called with
interrupts disabled; then all further accesses to our ecrypt fs hang
and we have to reboot.

The aesni-intel code (encrypting the core file that we are writing) needs
the FPU and quite properly wraps its code in kernel_fpu_{begin,end}(),
the latter of which calls math_state_restore(). So after kernel_fpu_end(),
interrupts may be disabled, which nobody seems to expect, and they stay
that way until we eventually get to __find_get_block() which barfs.

For eager fpu, most the time, tsk_used_math() is true. At few instances
during thread exit, signal return handling etc, tsk_used_math() might
be false.

In kernel_fpu_end(), for eager-fpu, call math_state_restore()
only if tsk_used_math() is set. Otherwise, don't bother. Kernel code
path which cleared tsk_used_math() knows what needs to be done
with the fpu state.

Reported-by: Maarten Baert <maarten-baert@hotmail.com>
Reported-by: Nate Eldredge <nate@thatsmathematics.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Suresh Siddha <sbsiddha@gmail.com>
Link: http://lkml.kernel.org/r/1391410583.3801.6.camel@europa
Cc: George Spelvin <linux@horizon.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
PNP / ACPI: proper handling of ACPI IO/Memory resource parsing failures

Before commit b355cee88e3b (ACPI / resources: ignore invalid ACPI
device resources), if acpi_dev_resource_memory()/acpi_dev_resource_io()
returns false, it means the the resource is not a memeory/IO resource.

But after commit b355cee88e3b, those functions return false if the
given memory/IO resource entry is invalid (the length of the resource
is zero).

This breaks pnpacpi_allocated_resource(), because it now recognizes
the invalid memory/io resources as resources of unknown type.  Thus
users see confusing warning messages on machines with zero length
ACPI memory/IO resources.

Fix the problem by rearranging pnpacpi_allocated_resource() so that
it calls acpi_dev_resource_memory() for memory type and IO type
resources only, respectively.

Fixes: b355cee88e3b (ACPI / resources: ignore invalid ACPI device resources)
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Reported-and-tested-by: Julian Wollrath <jwollrath@web.de>
Reported-and-tested-by: Paul Bolle <pebolle@tiscali.nl>
[rjw: Changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
dm cache: fix truncation bug when copying a block to/from >2TB fast device

During demotion or promotion to a cache's >2TB fast device we must not
truncate the cache block's associated sector to 32bits.  The 32bit
temporary result of from_cblock() caused a 32bit multiplication when
calculating the sector of the fast device in issue_copy_real().

Use an intermediate 64bit type to store the 32bit from_cblock() to allow
for proper 64bit multiplication.

Here is an example of how this bug manifests on an ext4 filesystem:

 EXT4-fs error (device dm-0): ext4_mb_generate_buddy:756: group 17136, 32768 clusters in bitmap, 30688 in gd; block bitmap corrupt.
 JBD2: Spotted dirty metadata buffer (dev = dm-0, blocknr = 0). There's a risk of filesystem corruption in case of system crash.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
dm cache: fix access beyond end of origin device

In order to avoid wasting cache space a partial block at the end of the
origin device is not cached.  Unfortunately, the check for such a
partial block at the end of the origin device was flawed.

Fix accesses beyond the end of the origin device that occured due to
attempted promotion of an undetected partial block by:

- initializing the per bio data struct to allow cache_end_io to work properly
- recognizing access to the partial block at the end of the origin device
- avoiding out of bounds access to the discard bitset

Otherwise, users can experience errors like the following:

 attempt to access beyond end of device
 dm-5: rw=0, want=20971520, limit=20971456
 ...
 device-mapper: cache: promotion failed; couldn't copy block

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
cpufreq: Skip current frequency initialization for ->setpolicy drivers

After commit da60ce9f2fac (cpufreq: call cpufreq_driver->get() after
calling ->init()) __cpufreq_add_dev() sometimes fails for CPUs handled
by intel_pstate, because that driver may return 0 from its ->get()
callback if it has not run long enough to collect enough samples on the
given CPU.  That didn't happen before commit da60ce9f2fac which added
policy->cur initialization to __cpufreq_add_dev() to help reduce code
duplication in other cpufreq drivers.

However, the code added by commit da60ce9f2fac need not be executed
for cpufreq drivers having the ->setpolicy callback defined, because
the subsequent invocation of cpufreq_set_policy() will use that
callback to initialize the policy anyway and it doesn't need
policy->cur to be initialized upfront.  The analogous code in
cpufreq_update_policy() is also unnecessary for cpufreq drivers
having ->setpolicy set and may be skipped for them as well.

Since intel_pstate provides ->setpolicy, skipping the upfront
policy->cur initialization for cpufreq drivers with that callback
set will cover intel_pstate and the problem it's been having after
commit da60ce9f2fac will be addressed.

Fixes: da60ce9f2fac (cpufreq: call cpufreq_driver->get() after calling ->init())
References: https://bugzilla.kernel.org/show_bug.cgi?id=71931
Reported-and-tested-by: Patrik Lundquist <patrik.lundquist@gmail.com>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Cc: 3.13+ <stable@vger.kernel.org> # 3.13+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / init: Invoke early ACPI initialization later

Commit 73f7d1ca3263 (ACPI / init: Run acpi_early_init() before
timekeeping_init()) optimistically moved the early ACPI initialization
before timekeeping_init(), but that didn't work, because it broke fast
TSC calibration for Julian Wollrath on Thinkpad x121e (and most likely
for others too).  The reason is that acpi_early_init() enables the SCI
and that interferes with the fast TSC calibration mechanism.

Thus follow the original idea to execute acpi_early_init() before
efi_enter_virtual_mode() to help the EFI people for now and we can
revisit the other problem that commit 73f7d1ca3263 attempted to
address in the future (if really necessary).

Fixes: 73f7d1ca3263 (ACPI / init: Run acpi_early_init() before timekeeping_init())
Reported-by: Julian Wollrath <jwollrath@web.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI / sleep: Add extra checks for HW Reduced ACPI mode sleep states

If the HW Reduced ACPI mode bit is set in the FADT, ACPICA uses
the optional sleep control and sleep status registers for making
the system enter sleep states (including S5), so it is not possible
to use system sleep states or power it off using ACPI if the HW
Reduced ACPI mode bit is set and those registers are not available.

For this reason, add a new function, acpi_sleep_state_supported(),
checking if the HW Reduced ACPI mode bit is set and whether or not
system sleep states are usable in that case in addition to checking
the return value of acpi_get_sleep_type_data() and make the ACPI
sleep setup routines use that function to check the availability of
system sleep states.

Among other things, this prevents the kernel from attempting to
use ACPI for powering off HW Reduced ACPI systems without the sleep
control and sleep status registers, because ACPI power off doesn't
have a chance to work on them.  That allows alternative power off
mechanisms that may actually work to be used on those systems.  The
affected machines include Dell Venue 8 Pro, Asus T100TA, Haswell
Desktop SDP and Ivy Bridge EP Demo depot.

References: https://bugzilla.kernel.org/show_bug.cgi?id=70931
Reported-by: Adam Williamson <awilliam@redhat.com>
Tested-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: 3.4+ <stable@vger.kernel.org> # 3.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge branches 'pnp', 'acpi-init', 'acpi-sleep' and 'pm-cpufreq'

* pnp:
  PNP / ACPI: proper handling of ACPI IO/Memory resource parsing failures

* acpi-init:
  ACPI / init: Invoke early ACPI initialization later

* acpi-sleep:
  ACPI / sleep: Add extra checks for HW Reduced ACPI mode sleep states

* pm-cpufreq:
  cpufreq: Skip current frequency initialization for ->setpolicy drivers
x86/amd/numa: Fix northbridge quirk to assign correct NUMA node

For systems with multiple servers and routed fabric, all
northbridges get assigned to the first server. Fix this by also
using the node reported from the PCI bus. For single-fabric
systems, the northbriges are on PCI bus 0 by definition, which
are on NUMA node 0 by definition, so this is invarient on most
systems.

Tested on fam10h and fam15h single and multi-fabric systems and
candidate for stable.

Signed-off-by: Daniel J Blueman <daniel@numascale.com>
Acked-by: Steffen Persvold <sp@numascale.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/1394710981-3596-1-git-send-email-daniel@numascale.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge tag 'dm-3.14-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device-mapper fixes form Mike Snitzer:
 "Two small fixes for the DM cache target:

   - fix corruption with >2TB fast device due to truncation bug
   - fix access beyond end of origin device due to a partial block"

* tag 'dm-3.14-fixes-4' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm cache: fix access beyond end of origin device
  dm cache: fix truncation bug when copying a block to/from >2TB fast device
Merge tag 'pm+acpi-3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI and power management fixes from Rafael Wysocki:
 "Three of these are regression fixes, for two recent regressions and
  one introduced during the 3.13 cycle, and the fourth one is a working
  version of the fix that had to be reverted last time.

  Specifics:

   - A recent ACPI resources handling fix overlooked the fact that it
     had to update the ACPI PNP subsystem's resources parsing too and
     caused confusing warning messages to be printed during system
     intialization on some systems (with arguably buggy ACPI tables).
     Fix from Zhang Rui.

   - Moving the early ACPI initialization before timekeeping_init()
     earlier in this cycle broke fast TSC calibration on at least one
     system, so it needs to be done later, but still before
     efi_enter_virtual_mode() to allow the EFI initialization to refer
     to ACPI.

   - A change related to code duplication reduction in the cpufreq core
     inadvertently caused cpufreq intialization to fail for some CPUs
     handled by intel_pstate by adding checks that may fail for that
     driver, but aren't even necessary when it is used.  The issue is
     addressed by preventing those checks from run in the configurations
     in which they aren't needed.

   - If the Hardware Reduced ACPI flag is set in the ACPI tables, system
     suspend, hibernation and ACPI power off will only work when special
     sleep control and sleep status registeres are provided (their
     addresses in the ACPI tables are not zero).  If those registers are
     not available, the features in question have no chances to work, so
     they shouldn't even be regarded as supported.  That helps with
     power off in particular, because alternative power off methods may
     be used then and they may actually work"

* tag 'pm+acpi-3.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / sleep: Add extra checks for HW Reduced ACPI mode sleep states
  ACPI / init: Invoke early ACPI initialization later
  cpufreq: Skip current frequency initialization for ->setpolicy drivers
  PNP / ACPI: proper handling of ACPI IO/Memory resource parsing failures
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Peter Anvin:
 "Two x86 fixes: Suresh's eager FPU fix, and a fix to the NUMA quirk for
  AMD northbridges.

  This only includes Suresh's fix patch, not the "mostly a cleanup"
  patch which had __init issues"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd/numa: Fix northbridge quirk to assign correct NUMA node
  x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPU