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Commit Graph

86067 Commits

Author SHA1 Message Date
Linus Torvalds
1ccfd5eaf8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull first batch of s390 updates from Martin Schwidefsky:
 "The most interesting change is that Martin converted s390 to generic
  hardirqs.  Which means that all current architectures have been
  converted and that CONFIG_GENERIC_HARDIRQS can be removed.  Martin
  prepared a patch for that already (see genirq branch), but the best
  time to merge that is probably at the end of the merge window / begin
  of -rc1.

  Another patch converts s390 to software referenced bits instead of
  relying on the reference bit in the storage key.  Therefore s390
  doesn't use storage keys anymore, except for kvm.

  Besides that we have improvements, cleanups and fixes in PCI, DASD and
  all over the place."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (32 commits)
  s390/pci: use virtual memory for iommu bitmap
  s390/cio: fix unlocked access of global bitmap
  s390/pci: update function handle after resume from hibernate
  s390/pci: try harder to modify a function
  s390/pci: split lpf
  s390/hibernate: add early resume function
  s390/pci: add recover sysfs knob
  s390/pci: use claim_resource
  s390/pci/hotplug: convert to be builtin only
  s390/mm: implement software referenced bits
  s390/dasd: fix statistics for recovered requests
  s390/tx: allow program interruption filtering in user space
  s390/pgtable: fix mprotect for single-threaded KVM guests
  s390/time: return with irqs disabled from psw_idle
  s390/kprobes: add support for compare and branch instructions
  s390/switch_to: fix save_access_regs() / restore_access_regs()
  s390/bitops: fix inline assembly constraints
  s390/dasd: enable raw_track_access reads without direct I/O
  s390/mm: introduce ptep_flush_lazy helper
  s390/time: clock comparator revalidation
  ...
2013-09-03 10:46:26 -07:00
Linus Torvalds
ea98af133f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
Pull m68k updates from Geert Uytterhoeven:
 "Summary:
   - Kill harmless warning messages when running a multi-platform kernel
     on Atari
   - Correct virt/phys mixups that didn't actually hurt due to identity
     mappings"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
  m68k/atari: ARAnyM - Always use physical addresses in NatFeat calls
  m68k: Ignore disabled HSYNC interrupt on Atari for irqs_disabled()
2013-09-03 10:45:29 -07:00
Linus Torvalds
fc6d0b0376 Merge branch 'lockref' (locked reference counts)
Merge lockref infrastructure code by me and Waiman Long.

I already merged some of the preparatory patches that didn't actually do
any semantic changes earlier, but this merges the actual _reason_ for
those preparatory patches.

The "lockref" structure is a combination "spinlock and reference count"
that allows optimized reference count accesses.  In particular, it
guarantees that the reference count will be updated AS IF the spinlock
was held, but using atomic accesses that cover both the reference count
and the spinlock words, we can often do the update without actually
having to take the lock.

This allows us to avoid the nastiest cases of spinlock contention on
large machines under heavy pathname lookup loads.  When updating the
dentry reference counts on a large system, we'll still end up with the
cache line bouncing around, but that's much less noticeable than
actually having to spin waiting for the lock.

* lockref:
  lockref: implement lockless reference count updates using cmpxchg()
  lockref: uninline lockref helper functions
  vfs: reimplement d_rcu_to_refcount() using lockref_get_or_lock()
  vfs: use lockref_get_not_zero() for optimistic lockless dget_parent()
  lockref: add 'lockref_get_or_lock() helper
2013-09-03 08:08:21 -07:00
Linus Torvalds
bc08b449ee lockref: implement lockless reference count updates using cmpxchg()
Instead of taking the spinlock, the lockless versions atomically check
that the lock is not taken, and do the reference count update using a
cmpxchg() loop.  This is semantically identical to doing the reference
count update protected by the lock, but avoids the "wait for lock"
contention that you get when accesses to the reference count are
contended.

Note that a "lockref" is absolutely _not_ equivalent to an atomic_t.
Even when the lockref reference counts are updated atomically with
cmpxchg, the fact that they also verify the state of the spinlock means
that the lockless updates can never happen while somebody else holds the
spinlock.

So while "lockref_put_or_lock()" looks a lot like just another name for
"atomic_dec_and_lock()", and both optimize to lockless updates, they are
fundamentally different: the decrement done by atomic_dec_and_lock() is
truly independent of any lock (as long as it doesn't decrement to zero),
so a locked region can still see the count change.

The lockref structure, in contrast, really is a *locked* reference
count.  If you hold the spinlock, the reference count will be stable and
you can modify the reference count without using atomics, because even
the lockless updates will see and respect the state of the lock.

In order to enable the cmpxchg lockless code, the architecture needs to
do three things:

 (1) Make sure that the "arch_spinlock_t" and an "unsigned int" can fit
     in an aligned u64, and have a "cmpxchg()" implementation that works
     on such a u64 data type.

 (2) define a helper function to test for a spinlock being unlocked
     ("arch_spin_value_unlocked()")

 (3) select the "ARCH_USE_CMPXCHG_LOCKREF" config variable in its
     Kconfig file.

This enables it for x86-64 (but not 32-bit, we'd need to make sure
cmpxchg() turns into the proper cmpxchg8b in order to enable it for
32-bit mode).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-02 12:12:15 -07:00
Linus Torvalds
e09a1fa9be Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot fix from Peter Anvin:
 "A single very small boot fix for very large memory systems (> 0.5T)"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix boot crash with DEBUG_PAGE_ALLOC=y and more than 512G RAM
2013-09-02 09:55:14 -07:00
Linus Torvalds
d9eda0fae1 ARM: SoC fixes for 3.11
Two straggling fixes that I had missed as they were posted a couple of
 weeks ago, causing problems with interrupts (breaking them completely)
 on the CSR SiRF platforms.
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Olof Johansson:
 "Two straggling fixes that I had missed as they were posted a couple of
  weeks ago, causing problems with interrupts (breaking them completely)
  on the CSR SiRF platforms"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  arm: prima2: drop nr_irqs in mach as we moved to linear irqdomain
  irqchip: sirf: move from legacy mode to linear irqdomain
2013-08-30 16:18:59 -07:00
Sebastian Ott
2245932155 s390/pci: use virtual memory for iommu bitmap
The bitmap used to mark dma mappings can be quite large on systems
with huge amounts of memory. Use virtual memory for this bitmap.

Suggested-by: Alexander Schmidt <alexschm@de.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:24 +02:00
Sebastian Ott
57b5918c33 s390/pci: update function handle after resume from hibernate
Function handles may change while the system was in hibernation
use list pci functions and update the function handles.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:20 +02:00
Sebastian Ott
d03abe5882 s390/pci: try harder to modify a function
In rare situations a PCI function can report a busy condition
when we issue the modify pci function command. A temporary busy
condition can exceed 1 second but not 2 seconds. Increase the
time until we report an error to 2 seconds. Also increase the
time we sleep between the retries to reduce the load in this
case.

Suggested-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:18 +02:00
Sebastian Ott
1d57896638 s390/pci: split lpf
List pci functions is used to query and iterate over pci functions.
This function currently has 2 users - initial device discovery and
rescan after a machine check. Instead of having a multipurpose
function pass a callback which gets called for each pci function.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:17 +02:00
Sebastian Ott
77e844b964 s390/hibernate: add early resume function
Some functions that do arch specific resume actions are called
directly from swsusp_asm64.S . Before we add another function call
provide a generic s390_early_resume function which can be used
for this purpose.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:15 +02:00
Sebastian Ott
0ff70ec88b s390/pci: add recover sysfs knob
Add an arch specific attribute to recover a pci function from an
error state or config space blockage.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:12 +02:00
Sebastian Ott
cb80918287 s390/pci: use claim_resource
Use pci_claim_resource to find and request bus ressources in
pcibios_add_device. Also move some (de)initialization stuff to
pcibios_enable_device/pcibios_disable_device.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:10 +02:00
Sebastian Ott
67f43f38ee s390/pci/hotplug: convert to be builtin only
Convert s390' pci hotplug to be builtin only, with no module option.

Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-30 08:57:07 +02:00
Barry Song
f8ab658b5d arm: prima2: drop nr_irqs in mach as we moved to linear irqdomain
we don't need nr_irqs in machine any more after we move to
linear irqdomain for sirfsoc irqchip, so drop them.

Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-29 09:48:36 -07:00
Martin Schwidefsky
0944fe3f4a s390/mm: implement software referenced bits
The last remaining use for the storage key of the s390 architecture
is reference counting. The alternative is to make page table entries
invalid while they are old. On access the fault handler marks the
pte/pmd as young which makes the pte/pmd valid if the access rights
allow read access. The pte/pmd invalidations required for software
managed reference bits cost a bit of performance, on the other hand
the RRBE/RRBM instructions to read and reset the referenced bits are
quite expensive as well.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-29 13:20:11 +02:00
Martin Schwidefsky
0628a5fbe1 s390/tx: allow program interruption filtering in user space
A user space program using the transactional execution facility
should be allowed to do program interrupt filtering. Do not set the
transactional-execution program-interruption-filtering override (PIFO)
bit in CR0.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-28 09:19:30 +02:00
Martin Schwidefsky
0196c642f7 s390/pgtable: fix mprotect for single-threaded KVM guests
For a single-threaded KVM guest ptep_modify_prot_start will not use
IPTE, the invalid bit will therefore not be set. If DEBUG_VM is set
pgste_set_key called by ptep_modify_prot_commit will complain about
the missing invalid bit. ptep_modify_prot_start should set the
invalid bit in all cases.

Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-28 09:19:28 +02:00
Martin Schwidefsky
0587d409ec s390/time: return with irqs disabled from psw_idle
Modify the psw_idle waiting logic in entry[64].S to return with
interrupts disabled. This avoids potential issues with udelay
and interrupt loops as interrupts are not reenabled after
clock comparator interrupts.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-28 09:19:23 +02:00
Linus Torvalds
0c6b5c5b45 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
Pull powerpc fixes from Ben Herrenschmidt:
 "Here are 3 bug fixes that should probably go into 3.11 since I'm also
  tagging them for stable.

  Once fixes our old /proc/powerpc/lparcfg file which provides partition
  informations when running under our hypervisor and also acts as a
  user-triggerable Oops when hot :-(

  The other two respectively are a one liner to fix a HVSI protocol
  handshake problem causing the console to fail to show up on a bunch of
  machines until we reach userspace, which I deem annoying enough to
  warrant going to stable, and a nasty gcc miscompile causing us to pass
  virtual instead of physical addresses to the firmware under some
  circumstances"

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc/hvsi: Increase handshake timeout from 200ms to 400ms.
  powerpc: Work around gcc miscompilation of __pa() on 64-bit
  powerpc: Don't Oops when accessing /proc/powerpc/lparcfg without hypervisor
2013-08-27 10:09:22 -07:00
Paul Mackerras
bdbc29c19b powerpc: Work around gcc miscompilation of __pa() on 64-bit
On 64-bit, __pa(&static_var) gets miscompiled by recent versions of
gcc as something like:

        addis 3,2,.LANCHOR1+4611686018427387904@toc@ha
        addi 3,3,.LANCHOR1+4611686018427387904@toc@l

This ends up effectively ignoring the offset, since its bottom 32 bits
are zero, and means that the result of __pa() still has 0xC in the top
nibble.  This happens with gcc 4.8.1, at least.

To work around this, for 64-bit we make __pa() use an AND operator,
and for symmetry, we make __va() use an OR operator.  Using an AND
operator rather than a subtraction ends up with slightly shorter code
since it can be done with a single clrldi instruction, whereas it
takes three instructions to form the constant (-PAGE_OFFSET) and add
it on.  (Note that MEMORY_START is always 0 on 64-bit.)

CC: <stable@vger.kernel.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-27 16:59:30 +10:00
Benjamin Herrenschmidt
f5f6cbb616 powerpc: Don't Oops when accessing /proc/powerpc/lparcfg without hypervisor
/proc/powerpc/lparcfg is an ancient facility (though still actively used)
which allows access to some informations relative to the partition when
running underneath a PAPR compliant hypervisor.

It makes no sense on non-pseries machines. However, currently, not only
can it be created on these if the kernel has pseries support, but accessing
it on such a machine will crash due to trying to do hypervisor calls.

In fact, it should also not do HV calls on older pseries that didn't have
an hypervisor either.

Finally, it has the plumbing to be a module but is a "bool" Kconfig option.

This fixes the whole lot by turning it into a machine_device_initcall
that is only created on pseries, and adding the necessary hypervisor
check before calling the H_GET_EM_PARMS hypercall

CC: <stable@vger.kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-27 16:38:33 +10:00
Linus Torvalds
1b4757ee6f Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM fixes from Russell King:
 "This round of fixes is smaller than previous: a couple more updates
  for the security fixes, and a one-liner kexec fix"

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7816/1: CONFIG_KUSER_HELPERS: fix help text
  ARM: 7815/1: kexec: offline non panic CPUs on Kdump panic
  ARM: 7819/1: fiq: Cast the first argument of flush_icache_range()
2013-08-25 12:41:37 -07:00
Joern Rennecke
b0f55f2a1a ARC: [lib] strchr breakage in Big-endian configuration
For a search buffer, 2 byte aligned, strchr() was returning pointer
outside of buffer (buf - 1)

------------->8----------------
    // Input buffer (default 4 byte aigned)
    char *buffer = "1AA_";

    // actual search start (to mimick 2 byte alignment)
    char *current_line = &(buffer[2]);

    // Character to search for
    char c = 'A';

    char *c_pos = strchr(current_line, c);

    printf("%s\n", c_pos) --> 'AA_' as oppose to 'A_'
------------->8----------------

Reported-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Debugged-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Cc: <stable@vger.kernel.org> # [3.9 and 3.10]
Cc: Noam Camus <noamc@ezchip.com>
Signed-off-by: Joern Rennecke  <joern.rennecke@embecosm.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-24 11:24:53 -07:00
Geert Uytterhoeven
55490050df m68k/atari: ARAnyM - Always use physical addresses in NatFeat calls
Pointers passed to ARAnyM NatFeat calls should be physical addresses,
not virtual addresses. This worked before because on Atari, physical and
virtual kernel addresses are the same, as long as normal kernel memory
is concerned.

Correct the few remaining places where virtual addresses were used.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2013-08-23 12:49:01 +02:00
Geert Uytterhoeven
3c776a0791 m68k: Ignore disabled HSYNC interrupt on Atari for irqs_disabled()
When running a multi-platform kernel on Atari, warning messages like
the following may be printed:

    WARNING: at /root/linux-3.10.1/init/main.c:698 do_one_initcall+0x12e/0x13a()
    initcall param_sysfs_init+0x0/0x1a4 returned with disabled interrupts

This is caused by the different definitions of ALLOWINT for Atari and
other platforms:

    #if defined(MACH_ATARI_ONLY)
    #define ALLOWINT        (~0x500)
    #else
    #define ALLOWINT        (~0x700)
    #endif

On Atari, we want to disable the high-frequency HSYNC interrupt:
  - On Atari-only kernels, this is handled completely through ALLOWINT,
  - On multi-platform kernels, this is handled by disabling the HSYNC
    interrupt from the interrupt handler.

However, as in the latter case arch_irqs_disabled_flags() didn't ignore the
disabling of the HSYNC interrupt, irqs_disabled() would detect false
positives.

Ignore the HSYNC interrupt when running on Atari to fix this.
For single-platform kernels this test is optimized away by the compiler.

Reported-by: Thorsten Glaser <tg@debian.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Thorsten Glaser <tg@debian.org>
2013-08-23 12:49:01 +02:00
Linus Torvalds
1f8b76656b ARM: SoC fixes for 3.11-rc
A handful of fixes for 3.11 are still trickling in. These are:
 - A couple of fixes for older OMAP platforms
 - Another few fixes for at91 (lateish due to European summer vacations)
 - A late-found problem with USB on Tegra, fix is to keep VBUS regulator
   on at all times
 - One fix for Exynos 5440 dealing with CPU detection
 - One MAINTAINERS update
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Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Olof Johansson:
 "A handful of fixes for 3.11 are still trickling in.  These are:
   - A couple of fixes for older OMAP platforms
   - Another few fixes for at91 (lateish due to European summer
     vacations)
   - A late-found problem with USB on Tegra, fix is to keep VBUS
     regulator on at all times
   - One fix for Exynos 5440 dealing with CPU detection
   - One MAINTAINERS update"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: tegra: always enable USB VBUS regulators
  ARM: davinci: nand: specify ecc strength
  ARM: OMAP: rx51: change musb mode to OTG
  ARM: OMAP2: fix musb usage for n8x0
  MAINTAINERS: Update email address for Benoit Cousson
  ARM: at91/DT: fix at91sam9n12ek memory node
  ARM: at91: add missing uart clocks DT entries
  ARM: SAMSUNG: fix to support for missing cpu specific map_io
  ARM: at91/DT: at91sam9x5ek: fix USB host property to enable port C
2013-08-22 10:44:44 -07:00
Radu Caragea
41aacc1eea x86 get_unmapped_area: Access mmap_legacy_base through mm_struct member
This is the updated version of df54d6fa54 ("x86 get_unmapped_area():
use proper mmap base for bottom-up direction") that only randomizes the
mmap base address once.

Signed-off-by: Radu Caragea <sinaelgl@gmail.com>
Reported-and-tested-by: Jeff Shorey <shoreyjeff@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Adrian Sendroiu <molecula2788@gmail.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-22 10:19:35 -07:00
Linus Torvalds
5ea80f76a5 Revert "x86 get_unmapped_area(): use proper mmap base for bottom-up direction"
This reverts commit df54d6fa54.

The commit isn't necessarily wrong, but because it recalculates the
random mmap_base every time, it seems to confuse user memory allocators
that expect contiguous mmap allocations even when the mmap address isn't
specified.

In particular, the MATLAB Java runtime seems to be unhappy. See

  https://bugzilla.kernel.org/show_bug.cgi?id=60774

So we'll want to apply the random offset only once, and Radu has a patch
for that.  Revert this older commit in order to apply the other one.

Reported-by: Jeff Shorey <shoreyjeff@gmail.com>
Cc: Radu Caragea <sinaelgl@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-22 10:18:44 -07:00
Heiko Carstens
6b169ac9b4 s390/kprobes: add support for compare and branch instructions
The compare and branch instructions (not relative) all need special
handling when kprobed:
- if a branch was taken, the instruction pointer should be left alone
- if a branch was not taken, the instruction pointer must be adjusted

The compare and branch instructions family was introduced with the general
instruction extension facility (z10).

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:12 +02:00
Heiko Carstens
bee5c2863e s390/switch_to: fix save_access_regs() / restore_access_regs()
Fix broken contraints for both save_access_regs() and restore_access_regs().
The constraints are incorrect since they tell the compiler that the inline
assemblies only access the first element of an array of 16 elements.
Therefore the compiler could generate incorrect code.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:11 +02:00
Heiko Carstens
02aff3aa17 s390/bitops: fix inline assembly constraints
Fix inline assembly contraints for non atomic bitops functions.

This is broken since 2.6.34 987bcdac "[S390] use inline assembly
contraints available with gcc 3.3.3".

Reported-by: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Reported-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:10 +02:00
Martin Schwidefsky
5c474a1e22 s390/mm: introduce ptep_flush_lazy helper
Isolate the logic of IDTE vs. IPTE flushing of ptes in two functions,
ptep_flush_lazy and __tlb_flush_mm_lazy.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:09 +02:00
Martin Schwidefsky
b6bed093f4 s390/time: clock comparator revalidation
Always use the S390_lowcore.clock_comparator field to revalidate
the clock comparator CPU register after a machine check. This avoids
an unnecssary external interrupt after a machine check if no timer
is pending.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:08 +02:00
Martin Schwidefsky
d56c893d36 s390/pgtable: add pgste_get helper
ptep_modify_prot_start uses the pgste_set helper to store the pgste,
while ptep_modify_prot_commit uses its own pointer magic to retrieve
the value again. Add the pgste_get help function to keep things
symmetrical and improve readability.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:07 +02:00
Martin Schwidefsky
a055f66a3a s390/pgtable: skip pgste updates on full flush
On process exit there is no more need for the pgste information.
Skip the expensive storage key operations which should speed up
termination of KVM processes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:06 +02:00
Martin Schwidefsky
e509861105 s390/mm: cleanup page table definitions
Improve the encoding of the different pte types and the naming of the
page, segment table and region table bits. Due to the different pte
encoding the hugetlbfs primitives need to be adapted as well. To improve
compatability with common code make the huge ptes use the encoding of
normal ptes. The conversion between the pte and pmd encoding for a huge
pte is done with set_huge_pte_at and huge_ptep_get.
Overall the code is now easier to understand.

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:06 +02:00
Heiko Carstens
416fd0ffb1 s390/mm: remove dead pfmf inline assembly
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:05 +02:00
Martin Schwidefsky
1f44a22577 s390: convert interrupt handling to use generic hardirq
With the introduction of PCI it became apparent that s390 should
convert to generic hardirqs as too many drivers do not have the
correct dependency for GENERIC_HARDIRQS. On the architecture
level s390 does not have irq lines. It has external interrupts,
I/O interrupts and adapter interrupts. This patch hard-codes all
external interrupts as irq #1, all I/O interrupts as irq #2 and
all adapter interrupts as irq #3. The additional information from
the lowcore associated with the interrupt is stored in the
pt_regs of the interrupt frame, where the interrupt handler can
pick it up. For PCI/MSI interrupts the adapter interrupt handler
scans the relevant bit fields and calls generic_handle_irq with
the virtual irq number for the MSI interrupt.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:04 +02:00
Martin Schwidefsky
5d0d8f4353 s390/pci: use adapter interrupt vector helpers
Make use of the adapter interrupt helpers in the PCI code. This is
the first step to convert the MSI interrupt code to PCI domains.
The patch removes the limitation of 64 adapter interrupts per
PCI function.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:03 +02:00
Martin Schwidefsky
9389339f28 s390/pci: cleanup function names
Rename s390pci_xyz to zpci_xxz and set_irq_ctrl to zpci_set_irq_ctrl.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:03 +02:00
Martin Schwidefsky
a9a6f0341d s390/airq: introduce adapter interrupt vector helper
The PCI code is the first user of adapter interrupts vectors.
Add a set of helpers to airq.c to separate the adatper interrupt
code from the PCI bits. The helpers allow for adapter interrupt
vectors of any size.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:02 +02:00
Heiko Carstens
958d9072b6 s390: replace remaining strict_strtoul() with kstrtoul()
Replace the last two strict_strtoul() with kstrtoul().

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22 12:20:00 +02:00
Stephen Warren
30ca2226be ARM: tegra: always enable USB VBUS regulators
This fixes a regression exposed during the merge window by commit
9f310de "ARM: tegra: fix VBUS regulator GPIO polarity in DT"; namely that
USB VBUS doesn't get turned on, so USB devices are not detected. This
affects the internal USB port on TrimSlice (i.e. the USB->SATA bridge, to
which the SSD is connected) and the external port(s) on Seaboard/
Springbank and Whistler.

The Tegra DT as written in v3.11 allows two paths to enable USB VBUS:

1) Via the legacy DT binding for the USB controller; it can directly
   acquire a VBUS GPIO and activate it.

2) Via a regulator for VBUS, which is referenced by the new DT binding
   for the USB controller.

Those two methods both use the same GPIO, and hence whichever of the
USB controller and regulator gets probed first ends up owning the GPIO.
In practice, the USB driver only supports path (1) above, since the
patches to support the new USB binding are not present until v3.12:-(

In practice, the regulator ends up being probed first and owning the
GPIO. Since nothing enables the regulator (the USB driver code is not
yet present), the regulator ends up being turned off. This originally
caused no problem, because the polarity in the regulator definition was
incorrect, so attempting to turn off the regulator actually turned it
on, and everything worked:-(

However, when testing the new USB driver code in v3.12, I noticed the
incorrect polarity and fixed it in commit 9f310de "ARM: tegra: fix VBUS
regulator GPIO polarity in DT". In the context of v3.11, this patch then
caused the USB VBUS to actually turn off, which broke USB ports with VBUS
control. I got this patch included in v3.11-rc1 since it fixed a bug in
device tree (incorrect polarity specification), and hence was suitable to
be included early in the rc series. I evidently did not test the patch at
all, or correctly, in the context of v3.11, and hence did not notice the
issue that I have explained above:-(

Fix this by making the USB VBUS regulators always enabled. This way, if
the regulator owns the GPIO, it will always be turned on, even if there
is no USB driver code to request the regulator be turned on. Even
ignoring this bug, this is a reasonable way to configure the HW anyway.

If this patch is applied to v3.11, it will cause a couple pretty trivial
conflicts in tegra20-{trimslice,seaboard}.dts when creating v3.12, since
the context right above the added lines changed in patches destined for
v3.12.

Reported-by: Kyle McMartin <kmcmarti@redhat.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-08-21 21:36:19 -07:00
Linus Torvalds
d936d2d452 Bug-fixes:
- On ARM did not have balanced calls to get/put_cpu.
  - Fix to make tboot + Xen + Linux correctly.
  - Fix events VCPU binding issues.
  - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU.
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Merge tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - On ARM did not have balanced calls to get/put_cpu.
 - Fix to make tboot + Xen + Linux correctly.
 - Fix events VCPU binding issues.
 - Fix a vCPU online race where IPIs are sent to not-yet-online vCPU.

* tag 'stable/for-linus-3.11-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/smp: initialize IPI vectors before marking CPU online
  xen/events: mask events when changing their VCPU binding
  xen/events: initialize local per-cpu mask for all possible events
  x86/xen: do not identity map UNUSABLE regions in the machine E820
  xen/arm: missing put_cpu in xen_percpu_init
2013-08-21 16:38:33 -07:00
Linus Torvalds
0903391acb Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fix from Ralf Baechle:
 "Just a single patch which fixes a special case in the MIPS FPU
  emulator which is always required, even on CPUs with FPU.  There is
  the rare special case that an FPU (or certain other instructions) in a
  branch delay slot is causing an exception and then the branch
  instruction will need to be emulated by the kernel before resuming
  execution.  This is working great except if the branch instruction is
  an Octeon BBIT instruction.

  The boring disclaimer - all MIPS defconfigs build tested and no
  regressions and runtime tested on Octeon, no known issues"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Handle OCTEON BBIT instructions in FPU emulator.
2013-08-21 16:37:14 -07:00
Linus Torvalds
7d06bafc4a Perf backend fixes for arm64 where the user can cause kernel panic
(discovered with Vince's fuzzing tool).
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Merge tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 perf fixes from Catalin Marinas:
 "Perf backend fixes for arm64 where the user can cause kernel panic
  (discovered with Vince's fuzzing tool)"

* tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: perf: fix event validation for software group leaders
  arm64: perf: fix array out of bounds access in armpmu_map_hw_event()
2013-08-21 16:36:32 -07:00
Linus Torvalds
69bbe136a9 Fixes for ARM and aarch64.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Fixes for ARM and aarch64.

  This pull request is coming a bit later than I would have preferred,
  because I and Gleb happened to have holidays around the same weeks of
  August...  sorry about that"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: ARM: Squash len warning
  arm64: KVM: use 'int' instead of 'u32' for variable 'target' in kvm_host.h.
  arm64: KVM: add missing dsb before invalidating Stage-2 TLBs
  arm64: KVM: perform save/restore of PAR_EL1
  arm64: KVM: fix 2-level page tables unmapping
  ARM: KVM: Fix unaligned unmap_range leak
  ARM: KVM: Fix 64-bit coprocessor handling
2013-08-21 16:35:37 -07:00
David Daney
c26d421987 MIPS: Handle OCTEON BBIT instructions in FPU emulator.
The branch emulation needs to handle the OCTEON BBIT instructions,
otherwise we get SIGILL instead of emulation.

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5726/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-08-20 19:17:40 +02:00
Chuck Anderson
fc78d343fa xen/smp: initialize IPI vectors before marking CPU online
An older PVHVM guest (v3.0 based) crashed during vCPU hot-plug with:

	kernel BUG at drivers/xen/events.c:1328!

RCU has detected that a CPU has not entered a quiescent state within the
grace period.  It needs to send the CPU a reschedule IPI if it is not
offline.  rcu_implicit_offline_qs() does this check:

	/*
	 * If the CPU is offline, it is in a quiescent state.  We can
	 * trust its state not to change because interrupts are disabled.
	 */
	if (cpu_is_offline(rdp->cpu)) {
		rdp->offline_fqs++;
		return 1;
	}

	Else the CPU is online.  Send it a reschedule IPI.

The CPU is in the middle of being hot-plugged and has been marked online
(!cpu_is_offline()).  See start_secondary():

	set_cpu_online(smp_processor_id(), true);
	...
	per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;

start_secondary() then waits for the CPU bringing up the hot-plugged CPU to
mark it as active:

	/*
	 * Wait until the cpu which brought this one up marked it
	 * online before enabling interrupts. If we don't do that then
	 * we can end up waking up the softirq thread before this cpu
	 * reached the active state, which makes the scheduler unhappy
	 * and schedule the softirq thread on the wrong cpu. This is
	 * only observable with forced threaded interrupts, but in
	 * theory it could also happen w/o them. It's just way harder
	 * to achieve.
	 */
	while (!cpumask_test_cpu(smp_processor_id(), cpu_active_mask))
		cpu_relax();

	/* enable local interrupts */
	local_irq_enable();

The CPU being hot-plugged will be marked active after it has been fully
initialized by the CPU managing the hot-plug.  In the Xen PVHVM case
xen_smp_intr_init() is called to set up the hot-plugged vCPU's
XEN_RESCHEDULE_VECTOR.

The hot-plugging CPU is marked online, not marked active and does not have
its IPI vectors set up.  rcu_implicit_offline_qs() sees the hot-plugging
cpu is !cpu_is_offline() and tries to send it a reschedule IPI:
This will lead to:

	kernel BUG at drivers/xen/events.c:1328!

	xen_send_IPI_one()
	xen_smp_send_reschedule()
	rcu_implicit_offline_qs()
	rcu_implicit_dynticks_qs()
	force_qs_rnp()
	force_quiescent_state()
	__rcu_process_callbacks()
	rcu_process_callbacks()
	__do_softirq()
	call_softirq()
	do_softirq()
	irq_exit()
	xen_evtchn_do_upcall()

because xen_send_IPI_one() will attempt to use an uninitialized IRQ for
the XEN_RESCHEDULE_VECTOR.

There is at least one other place that has caused the same crash:

	xen_smp_send_reschedule()
	wake_up_idle_cpu()
	add_timer_on()
	clocksource_watchdog()
	call_timer_fn()
	run_timer_softirq()
	__do_softirq()
	call_softirq()
	do_softirq()
	irq_exit()
	xen_evtchn_do_upcall()
	xen_hvm_callback_vector()

clocksource_watchdog() uses cpu_online_mask to pick the next CPU to handle
a watchdog timer:

	/*
	 * Cycle through CPUs to check if the CPUs stay synchronized
	 * to each other.
	 */
	next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask);
	if (next_cpu >= nr_cpu_ids)
		next_cpu = cpumask_first(cpu_online_mask);
	watchdog_timer.expires += WATCHDOG_INTERVAL;
	add_timer_on(&watchdog_timer, next_cpu);

This resulted in an attempt to send an IPI to a hot-plugging CPU that
had not initialized its reschedule vector. One option would be to make
the RCU code check to not check for CPU offline but for CPU active.
As becoming active is done after a CPU is online (in older kernels).

But Srivatsa pointed out that "the cpu_active vs cpu_online ordering has been
completely reworked - in the online path, cpu_active is set *before* cpu_online,
and also, in the cpu offline path, the cpu_active bit is reset in the CPU_DYING
notification instead of CPU_DOWN_PREPARE." Drilling in this the bring-up
path: "[brought up CPU].. send out a CPU_STARTING notification, and in response
to that, the scheduler sets the CPU in the cpu_active_mask. Again, this mask
is better left to the scheduler alone, since it has the intelligence to use it
judiciously."

The conclusion was that:
"
1. At the IPI sender side:

   It is incorrect to send an IPI to an offline CPU (cpu not present in
   the cpu_online_mask). There are numerous places where we check this
   and warn/complain.

2. At the IPI receiver side:

   It is incorrect to let the world know of our presence (by setting
   ourselves in global bitmasks) until our initialization steps are complete
   to such an extent that we can handle the consequences (such as
   receiving interrupts without crashing the sender etc.)
" (from Srivatsa)

As the native code enables the interrupts at some point we need to be
able to service them. In other words a CPU must have valid IPI vectors
if it has been marked online.

It doesn't need to handle the IPI (interrupts may be disabled) but needs
to have valid IPI vectors because another CPU may find it in cpu_online_mask
and attempt to send it an IPI.

This patch will change the order of the Xen vCPU bring-up functions so that
Xen vectors have been set up before start_secondary() is called.
It also will not continue to bring up a Xen vCPU if xen_smp_intr_init() fails
to initialize it.

Orabug 13823853
Signed-off-by Chuck Anderson <chuck.anderson@oracle.com>
Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2013-08-20 10:13:05 -04:00