Commit Graph

75004 Commits

Author SHA1 Message Date
Linus Torvalds
2b1768f39a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:
 "Several build/bug fixes for sparc, including:

  1) Configuring a mix of static vs.  modular sparc64 crypto modules
     didn't work, remove an ill-conceived attempt to only have to build
     the device match table for these drivers once to fix the problem.

     Reported by Meelis Roos.

  2) Make the montgomery multiple/square and mpmul instructions actually
     usable in 32-bit tasks.  Essentially this involves providing 32-bit
     userspace with a way to use a 64-bit stack when it needs to.

  3) Our sparc64 atomic backoffs don't yield cpu strands properly on
     Niagara chips.  Use pause instruction when available to achieve
     this, otherwise use a benign instruction we know blocks the strand
     for some time.

  4) Wire up kcmp

  5) Fix the build of various drivers by removing the unnecessary
     blocking of OF_GPIO when SPARC.

  6) Fix unintended regression wherein of_address_to_resource stopped
     being provided.  Fix from Andreas Larsson.

  7) Fix NULL dereference in leon_handle_ext_irq(), also from Andreas
     Larsson."

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix build with mix of modular vs. non-modular crypto drivers.
  sparc: Support atomic64_dec_if_positive properly.
  of/address: sparc: Declare of_address_to_resource() as an extern function for sparc again
  sparc32, leon: Check for existent irq_map entry in leon_handle_ext_irq
  sparc: Add sparc support for platform_get_irq()
  sparc: Allow OF_GPIO on sparc.
  qlogicpti: Fix build warning.
  sparc: Wire up sys_kcmp.
  sparc64: Improvde documentation and readability of atomic backoff code.
  sparc64: Use pause instruction when available.
  sparc64: Fix cpu strand yielding.
  sparc64: Make montmul/montsqr/mpmul usable in 32-bit threads.
2012-11-10 21:58:34 +01:00
Linus Torvalds
487bda54d7 AArch64 kernel fixes:
- correct argument type (pgprot_t) when calling __ioremap()
 - PCI_IOBASE virtual address change
 - use architected event for CPU cycle counter
 - fix ELF core dumping
 - select CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
 - missing completion for secondary CPU boot
 - booting on systems with all memory beyond 4GB
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Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 fixes from Catalin Marinas:
 - correct argument type (pgprot_t) when calling __ioremap()
 - PCI_IOBASE virtual address change
 - use architected event for CPU cycle counter
 - fix ELF core dumping
 - select CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
 - missing completion for secondary CPU boot
 - booting on systems with all memory beyond 4GB

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: mm: fix booting on systems with no memory below 4GB
  arm64: smp: add missing completion for secondary boot
  arm64: compat: select CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
  arm64: elf: fix core dumping definitions for GP and FP registers
  arm64: perf: use architected event for CPU cycle counter
  arm64: Move PCI_IOBASE closer to MODULES_VADDR
  arm64: Use pgprot_t as the last argument when invoking __ioremap()
2012-11-10 06:58:20 +01:00
Linus Torvalds
0020dd0b8c Bug-fixes:
* Fix compile issues on ARM.
  * Fix hypercall fallback code for old hypervisors.
  * Print out which HVM parameter failed if it fails.
  * Fix idle notifier call after irq_enter.
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Merge tag 'stable/for-linus-3.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen fixes from Konrad Rzeszutek Wilk:
 "There are three ARM compile fixes (we forgot to export certain
  functions and if the drivers are built as an module - we go belly-up).

  There is also an mismatch of irq_enter() / exit_idle() calls sequence
  which were fixed some time ago in other piece of codes, but failed to
  appear in the Xen code.

  Lastly a fix for to help in the field with troubleshooting in case we
  cannot get the appropriate parameter and also fallback code when
  working with very old hypervisors."

Bug-fixes:
 - Fix compile issues on ARM.
 - Fix hypercall fallback code for old hypervisors.
 - Print out which HVM parameter failed if it fails.
 - Fix idle notifier call after irq_enter.

* tag 'stable/for-linus-3.7-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/arm: Fix compile errors when drivers are compiled as modules (export more).
  xen/arm: Fix compile errors when drivers are compiled as modules.
  xen/generic: Disable fallback build on ARM.
  xen/events: fix RCU warning, or Call idle notifier after irq_enter()
  xen/hvm: If we fail to fetch an HVM parameter print out which flag it is.
  xen/hypercall: fix hypercall fallback code for very old hypervisors
2012-11-10 06:56:21 +01:00
David S. Miller
226f7cea94 sparc64: Fix build with mix of modular vs. non-modular crypto drivers.
We tried linking in a single built object to hold the device table,
but only works if all of the sparc64 crypto modules get built the same
way (modular vs. non-modular).

Just include the device ID stub into each driver source file so that
the table gets compiled into the correct result in all cases.

Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-09 20:55:16 -08:00
David S. Miller
193d2aadc0 sparc: Support atomic64_dec_if_positive properly.
Sparc32 already supported it, as a consequence of using the
generic atomic64 implementation.  And the sparc64 implementation
is rather trivial.

This allows us to set ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE for all
of sparc, and avoid the annoying warning from lib/atomic64_test.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-09 19:37:59 -08:00
Andreas Larsson
0bce04be44 of/address: sparc: Declare of_address_to_resource() as an extern function for sparc again
This bug-fix makes sure that of_address_to_resource is defined extern for sparc
so that the sparc-specific implementation of of_address_to_resource() is once
again used when including include/linux/of_address.h in a sparc context. A
number of drivers in mainline relies on this function working for sparc.

The bug was introduced in a850a75544, "of/address:
add empty static inlines for !CONFIG_OF". Contrary to that commit title, the
static inlines are added for !CONFIG_OF_ADDRESS, and CONFIG_OF_ADDRESS is never
defined for sparc. This is good behavior for the other functions in
include/linux/of_address.h, as the extern functions defined in
drivers/of/address.c only gets linked when OF_ADDRESS is configured. However,
for of_address_to_resource there exists a sparc-specific implementation in
arch/sparc/arch/sparc/kernel/of_device_common.c

Solution suggested by: Sam Ravnborg <sam@ravnborg.org>

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-09 16:30:50 -08:00
Andreas Larsson
20424d85f8 sparc32, leon: Check for existent irq_map entry in leon_handle_ext_irq
If an irq is being unlinked concurrently with leon_handle_ext_irq,
irq_map[eirq] might be null in leon_handle_ext_irq. Make sure that
this is not dereferenced.

Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-09 16:30:50 -08:00
Stefano Stabellini
ab277bbf66 xen/arm: Fix compile errors when drivers are compiled as modules (export more).
The commit 911dec0db4
"xen/arm: Fix compile errors when drivers are compiled as modules." exports
the neccessary functions. But to guard ourselves against out-of-tree modules
and future drivers hitting this, lets export all of the relevant
hypercalls.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-09 07:48:22 -05:00
Linus Torvalds
4ad48bb72c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Martin Schwidefsky:
 "A couple of bug fixes.  I keep the fingers crossed that we now got
  transparent huge pages ready for prime time."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/cio: fix length calculation in idset.c
  s390/sclp: fix addressing mode clobber
  s390: Move css limits from drivers/s390/cio/ to include/asm/.
  s390/thp: respect page protection in pmd_none() and pmd_present()
  s390/mm: use pmd_large() instead of pmd_huge()
  s390/cio: suppress 2nd path verification during resume
2012-11-09 06:57:56 +01:00
Linus Torvalds
ce6d841e9c Merge branch 'akpm' (Fixes from Andrew)
Merge misc fixes from Andrew Morton:
 "Five fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (5 patches)
  h8300: add missing L1_CACHE_SHIFT
  mm: bugfix: set current->reclaim_state to NULL while returning from kswapd()
  fanotify: fix missing break
  revert "epoll: support for disabling items, and a self-test app"
  checkpatch: improve network block comment style checking
2012-11-09 06:53:02 +01:00
Fengguang Wu
6893f5675f h8300: add missing L1_CACHE_SHIFT
Fix the build error

  lib/atomic64.c: In function 'lock_addr':
  lib/atomic64.c:40:11: error: 'L1_CACHE_SHIFT' undeclared (first use in this function)
  lib/atomic64.c:40:11: note: each undeclared identifier is reported only once for each function it appears in

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-09 06:41:47 +01:00
Will Deacon
f483a853b0 arm64: mm: fix booting on systems with no memory below 4GB
Booting on a system with all of its memory above the 4GB boundary breaks
for two reasons:

	(1) We still try to create a non-empty DMA32 zone
	(2) no-bootmem limits allocations to 0xffffffff

This patch fixes these issues for ARM64.

Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-11-08 16:06:21 +00:00
Will Deacon
b3770b3252 arm64: smp: add missing completion for secondary boot
Commit 149c24151e ("ARM: SMP: use a timing out completion for cpu
hotplug") modified arm's CPU up path to use completions. It seems that
we only got half of this patch for arm64, so add the missing call to
complete.

Reported-by: Jon Brawn <jon.brawn@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-11-08 16:06:21 +00:00
Will Deacon
6212a51224 arm64: compat: select CONFIG_ARCH_WANT_COMPAT_IPC_PARSE_VERSION
Commit c1d7e01d78 ("ipc: use Kconfig options for
__ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION") replaced the
__ARCH_WANT_COMPAT_IPC_PARSE_VERSION token with a corresponding Kconfig
option instead.

This patch updates arm64 to use the latter, rather than #define an
unused token.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-11-08 16:06:20 +00:00
Will Deacon
6ba1bc826d arm64: elf: fix core dumping definitions for GP and FP registers
struct user_fp does not exist for arm64, so use struct user_fpsimd_state
instead for the ELF core dumping definitions. Furthermore, since we use
regset-based core dumping, we do not need definitions for dump_task_regs
and dump_fpu.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-11-08 16:06:20 +00:00
Will Deacon
f46f979fda arm64: perf: use architected event for CPU cycle counter
We currently use a fake event encoding (0xFF) to indicate CPU cycles so
that we don't waste an event counter and can target the hardware cycle
counter instead.

The problem with this approach is that the event space defined by the
architecture permits an implementation to allocate 0xFF for some other
event.

This patch uses the architected cycle counter encoding (0x11) so that
we avoid potentially clashing with event encodings on future CPU
implementations.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2012-11-08 16:06:19 +00:00
Konrad Rzeszutek Wilk
911dec0db4 xen/arm: Fix compile errors when drivers are compiled as modules.
We end up with:

ERROR: "HYPERVISOR_event_channel_op" [drivers/xen/xen-gntdev.ko] undefined!
ERROR: "privcmd_call" [drivers/xen/xen-privcmd.ko] undefined!
ERROR: "HYPERVISOR_grant_table_op" [drivers/net/xen-netback/xen-netback.ko] undefined!

and this patch exports said function (which is implemented in hypercall.S).

Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-07 10:46:19 -05:00
Linus Torvalds
3cc5a2ee7f Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm
Pull arm fixes from Russell King:
 "Not much here again.

  The two most notable things here are the sched_clock() fix, which was
  causing problems with the scheduling of threaded IRQs after a suspend
  event, and the vfp fix, which afaik has only been seen on some older
  OMAP boards.  Nevertheless, both are fairly important fixes."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7569/1: mm: uninitialized warning corrections
  ARM: 7567/1: io: avoid GCC's offsettable addressing modes for halfword accesses
  ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set
  ARM: 7565/1: sched: stop sched_clock() during suspend
2012-11-07 04:14:45 +01:00
Heiko Carstens
99e639b791 s390/sclp: fix addressing mode clobber
The early mini sclp driver may be called in zArch mode either in
31 or 64 bit addressing mode.
If called in 31 bit addressing mode the new external interrupt psw
however would switch to 64 bit addressing mode. This would cause an
addressing exception within the interrupt handler, since the code
didn't expect the zArch/31 bit addressing mode combination.

Fix this by setting the new psw addressing mode bits so they fit
the current addressing mode.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-06 22:39:51 +01:00
Cornelia Huck
619506d5da s390: Move css limits from drivers/s390/cio/ to include/asm/.
There's no need to keep __MAX_SUBCHANNEL and __MAX_SSID private to the
common I/O layer when __MAX_CSSID is usable by everybody.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-06 22:39:49 +01:00
Catalin Marinas
3fd9396af8 Linux 3.7-rc4
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Merge tag 'v3.7-rc4' into upstream-master

Linux 3.7-rc4
2012-11-05 14:58:32 +00:00
Jan Beulich
cf47a83fb0 xen/hypercall: fix hypercall fallback code for very old hypervisors
While copying the argument structures in HYPERVISOR_event_channel_op()
and HYPERVISOR_physdev_op() into the local variable is sufficiently
safe even if the actual structure is smaller than the container one,
copying back eventual output values the same way isn't: This may
collide with on-stack variables (particularly "rc") which may change
between the first and second memcpy() (i.e. the second memcpy() could
discard that change).

Move the fallback code into out-of-line functions, and handle all of
the operations known by this old a hypervisor individually: Some don't
require copying back anything at all, and for the rest use the
individual argument structures' sizes rather than the container's.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
[v2: Reduce #define/#undef usage in HYPERVISOR_physdev_op_compat().]
[v3: Fix compile errors when modules use said hypercalls]
[v4: Add xen_ prefix to the HYPERCALL_..]
[v5: Alter the name and only EXPORT_SYMBOL_GPL one of them]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-11-04 10:40:42 -05:00
viresh kumar
6404f0b71c ARM: 7569/1: mm: uninitialized warning corrections
The variables here are really not used uninitialized.

arch/arm/mm/alignment.c: In function 'do_alignment':
arch/arm/mm/alignment.c:327:15: warning: 'offset.un' may be used uninitialized in this function [-Wmaybe-uninitialized]
arch/arm/mm/alignment.c:748:21: note: 'offset.un' was declared here

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-11-04 10:32:40 +00:00
Linus Torvalds
b987a834f6 FRV fixes for 3.7
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Merge tag 'frv-fixes-20121102' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-frv

Pull FRV fixes from David Howells:
 "A collection of small fixes for the FRV architecture."

* tag 'frv-fixes-20121102' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-frv:
  frv: fix the broken preempt
  frv: switch to saner kernel_execve() semantics
  FRV: Fix the new-style kernel_thread() stuff
  FRV: Fix the preemption handling
  FRV: gcc-4.1.2 also inlines weak functions
  FRV: Don't objcopy the GNU build_id note
  FRV: Add missing linux/export.h #inclusions
2012-11-02 13:27:01 -07:00
Linus Torvalds
66b6a0c979 Bug-fixes:
* Use appropriate macros instead of hand-rolling our own (ARM).
  * Fixes if FB/KBD closed unexpectedly.
  * Fix memory leak in /dev/gntdev ioctl calls.
  * Fix overflow check in xenbus_file_write.
  * Document cleanup.
  * Performance optimization when migrating guests.
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Merge tag 'stable/for-linus-3.7-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen bugfixes from Konrad Rzeszutek Wilk:
 - Use appropriate macros instead of hand-rolling our own (ARM).
 - Fixes if FB/KBD closed unexpectedly.
 - Fix memory leak in /dev/gntdev ioctl calls.
 - Fix overflow check in xenbus_file_write.
 - Document cleanup.
 - Performance optimization when migrating guests.

* tag 'stable/for-linus-3.7-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/mmu: Use Xen specific TLB flush instead of the generic one.
  xen/arm: use the __HVC macro
  xen/xenbus: fix overflow check in xenbus_file_write()
  xen-kbdfront: handle backend CLOSED without CLOSING
  xen-fbfront: handle backend CLOSED without CLOSING
  xen/gntdev: don't leak memory from IOCTL_GNTDEV_MAP_GRANT_REF
  x86: remove obsolete comment from asm/xen/hypervisor.h
2012-11-02 13:26:11 -07:00
Al Viro
1d72d9f83d frv: fix the broken preempt
Just get %icc2 into the state we would have after local_irq_disable()
and physical IRQ having happened since then.  Then we can simply
use preempt_schedule_irq() and be done with the whole mess.

Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-02 12:08:25 -04:00
Al Viro
7b7ade1179 frv: switch to saner kernel_execve() semantics
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-02 12:05:04 -04:00
David Howells
e7aa51b2e5 FRV: Fix the new-style kernel_thread() stuff
The kernel_thread() changes for FRV don't work, and FRV fails to boot,
starting with:

	commit 02ce496f15
	Author: Al Viro <viro@zeniv.linux.org.uk>
	Date:   Tue Sep 18 22:18:51 2012 -0400
	Subject: frv: split ret_from_fork, simplify kernel_thread() a lot

The problem is that the userspace registers are completely cleared when a
kernel thread is created and all subsequent user threads are then copied from
that.  Unfortunately, however, the TBR and PSR registers are restored from the
pt_regs and the values they should be set to are clobbered by the memset.

Instead, copy across the old user registers as normal, and then merely alter
GR8 and GR9 in it if we're going to execute a kernel thread.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-11-02 13:20:43 +00:00
David Howells
1ee6f5669a FRV: Fix the preemption handling
Fix the preemption handling in FRV code where the PREEMPT_ACTIVE value is
incorrectly loaded into the threadinfo flags rather than the threadinfo
preemption count.

Unfortunately, the code cannot be simply converted to use
preempt_schedule_irq() as is because FRV uses virtual interrupt disablement to
cut down on the cost of actually disabling interrupts and thus
local_irq_enable() doesn't actually enable interrupts.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Al Viro <viro@ZenIV.linux.org.uk>
2012-11-02 13:20:42 +00:00
David Howells
5f0231d97b FRV: Don't objcopy the GNU build_id note
Don't let objcopy transfer the GNU build_id note into the loadable image as it
is located at address 0 and the image ends up >3G in size.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-11-02 13:20:42 +00:00
David Howells
a5788caa26 FRV: Add missing linux/export.h #inclusions
Add missing linux/export.h #inclusions to the FRV arch.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-11-02 13:20:42 +00:00
Linus Torvalds
c660b8f944 Xtensa patchset for 3.7-rc4
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Merge tag 'xtensa-next-20121101' of git://github.com/czankel/xtensa-linux

Pull Xtensa fixes from Chris Zankel:
 "Some important bug fixes.

  With the change to uapi, there was a bug introduced that results in an
  empty syscall table (mult-inclusion bug).  Switching to the generic
  thread/execve allowed us to fix a bug we had in vfork()."

* tag 'xtensa-next-20121101' of git://github.com/czankel/xtensa-linux:
  xtensa: switch to generic sys_execve()
  xtensa: switch to generic kernel_execve()
  xtensa: switch to generic kernel_thread()
  xtensa: reset windowbase/windowstart when cloning the VM
  xtensa: use physical addresses for bus addresses
  xtensa: allow multi-inclusion for uapi/unistd.h
2012-11-01 17:48:19 -07:00
Xiao Guangrong
87da7e66a4 KVM: x86: fix vcpu->mmio_fragments overflow
After commit b3356bf0db (KVM: emulator: optimize "rep ins" handling),
the pieces of io data can be collected and write them to the guest memory
or MMIO together

Unfortunately, kvm splits the mmio access into 8 bytes and store them to
vcpu->mmio_fragments. If the guest uses "rep ins" to move large data, it
will cause vcpu->mmio_fragments overflow

The bug can be exposed by isapc (-M isapc):

[23154.818733] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
[ ......]
[23154.858083] Call Trace:
[23154.859874]  [<ffffffffa04f0e17>] kvm_get_cr8+0x1d/0x28 [kvm]
[23154.861677]  [<ffffffffa04fa6d4>] kvm_arch_vcpu_ioctl_run+0xcda/0xe45 [kvm]
[23154.863604]  [<ffffffffa04f5a1a>] ? kvm_arch_vcpu_load+0x17b/0x180 [kvm]

Actually, we can use one mmio_fragment to store a large mmio access then
split it when we pass the mmio-exit-info to userspace. After that, we only
need two entries to store mmio info for the cross-mmio pages access

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-10-31 20:36:30 -02:00
Konrad Rzeszutek Wilk
95a7d76897 xen/mmu: Use Xen specific TLB flush instead of the generic one.
As Mukesh explained it, the MMUEXT_TLB_FLUSH_ALL allows the
hypervisor to do a TLB flush on all active vCPUs. If instead
we were using the generic one (which ends up being xen_flush_tlb)
we end up making the MMUEXT_TLB_FLUSH_LOCAL hypercall. But
before we make that hypercall the kernel will IPI all of the
vCPUs (even those that were asleep from the hypervisor
perspective). The end result is that we needlessly wake them
up and do a TLB flush when we can just let the hypervisor
do it correctly.

This patch gives around 50% speed improvement when migrating
idle guest's from one host to another.

Oracle-bug: 14630170

CC: stable@vger.kernel.org
Tested-by:  Jingjie Jiang <jingjie.jiang@oracle.com>
Suggested-by:  Mukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-31 12:38:31 -04:00
Stefano Stabellini
c8d258a7b2 xen/arm: use the __HVC macro
Use the new __HVC macro in hypercall.S.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30 10:41:19 -04:00
Olaf Hering
b6514633bd x86: remove obsolete comment from asm/xen/hypervisor.h
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-10-30 09:27:32 -04:00
Will Deacon
7629a9f661 ARM: 7567/1: io: avoid GCC's offsettable addressing modes for halfword accesses
Using the 'o' memory constraint in inline assembly can result in GCC
generating invalid immediate offsets for memory access instructions with
reduced addressing capabilities (i.e. smaller than 12-bit immediate
offsets):

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54983

As there is no constraint to specify the exact addressing mode we need,
fallback to using 'Q' exclusively for halfword I/O accesses. This may
emit an additional add instruction (using an extra register) in order
to construct the address but it will always be accepted by GAS.

Reported-by: Bastian Hecht <hechtb@googlemail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-29 10:04:27 +00:00
Paul Walmsley
39141ddfb6 ARM: 7566/1: vfp: fix save and restore when running on pre-VFPv3 and CONFIG_VFPv3 set
After commit 846a136881 ("ARM: vfp: fix
saving d16-d31 vfp registers on v6+ kernels"), the OMAP 2430SDP board
started crashing during boot with omap2plus_defconfig:

[    3.875122] mmcblk0: mmc0:e624 SD04G 3.69 GiB
[    3.915954]  mmcblk0: p1
[    4.086639] Internal error: Oops - undefined instruction: 0 [#1] SMP ARM
[    4.093719] Modules linked in:
[    4.096954] CPU: 0    Not tainted  (3.6.0-02232-g759e00b #570)
[    4.103149] PC is at vfp_reload_hw+0x1c/0x44
[    4.107666] LR is at __und_usr_fault_32+0x0/0x8

It turns out that the context save/restore fix unmasked a latent bug
in commit 5aaf254409 ("ARM: 6203/1: Make
VFPv3 usable on ARMv6").  When CONFIG_VFPv3 is set, but the kernel is
booted on a pre-VFPv3 core, the code attempts to save and restore the
d16-d31 VFP registers.  These are only present on non-D16 VFPv3+, so
this results in an undefined instruction exception.  The code didn't
crash before commit 846a136 because the save and restore code was
only touching d0-d15, present on all VFP.

Fix by implementing a request from Russell King to add a new HWCAP
flag that affirmatively indicates the presence of the d16-d31
registers:

   http://marc.info/?l=linux-arm-kernel&m=135013547905283&w=2

and some feedback from Måns to clarify the name of the HWCAP flag.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Martin <dave.martin@linaro.org>
Cc: Måns Rullgård <mans.rullgard@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-29 10:04:05 +00:00
Felipe Balbi 2
6a4dae5e13 ARM: 7565/1: sched: stop sched_clock() during suspend
The scheduler imposes a requirement to sched_clock()
which is to stop the clock during suspend, if we don't
do that any RT thread will be rescheduled in the future
which might cause any sort of problems.

This became an issue on OMAP when we converted omap-i2c.c
to use threaded IRQs, it turned out that depending on how
much time we spent on suspend, the I2C IRQ thread would
end up being rescheduled so far in the future that I2C
transfers would timeout and, because omap_hsmmc depends
on an I2C-connected device to detect if an MMC card is
inserted in the slot, our rootfs would just vanish.

arch/arm/kernel/sched_clock.c already had an optional
implementation (sched_clock_needs_suspend()) which would
handle scheduler's requirement properly, what this patch
does is simply to make that implementation non-optional.

Note that this has the side-effect that printk timings
won't reflect the actual time spent on suspend so other
methods to measure that will have to be used.

This has been tested with beagleboard XM (OMAP3630) and
pandaboard rev A3 (OMAP4430). Suspend to RAM is now working
after this patch.

Thanks to Kevin Hilman for helping out with debugging.

Acked-by: Kevin Hilman <khilman@ti.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-10-29 10:02:49 +00:00
David S. Miller
1df35f80f9 sparc: Wire up sys_kcmp.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-28 13:15:09 -07:00
David S. Miller
187818cd6a sparc64: Improvde documentation and readability of atomic backoff code.
Document what's going on in asm/backoff.h with a large and descriptive
comment.  Refer to it above the cpu_relax() definition in
asm/processor_64.h

Rename the pause patching section to have "3insn" in it's name like
the other patching sections do.

Based upon feedback from Sam Ravnborg.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-28 13:04:47 -07:00
Linus Torvalds
065c8012b2 arm-soc: fixes for v3.7-rc3
Bug fixes for a number of ARM platforms, mostly OMAP, imx and at91.
 These come a little later than I had hoped but unfortunately we
 had a few of these patches cause regressions themselves and had to
 work out how to deal with those in the meantime.
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Merge tag 'fixes-for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull arm-soc fixes from Arnd Bergmann:
 "Bug fixes for a number of ARM platforms, mostly OMAP, imx and at91.

  These come a little later than I had hoped but unfortunately we had a
  few of these patches cause regressions themselves and had to work out
  how to deal with those in the meantime."

* tag 'fixes-for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (38 commits)
  Revert "ARM i.MX25: Fix PWM per clock lookups"
  ARM: versatile: fix versatile_defconfig
  ARM: mvebu: update defconfig with 3.7 changes
  ARM: at91: fix at91x40 build
  ARM: socfpga: Fix socfpga compilation with early_printk() enabled
  ARM: SPEAr: Remove unused empty files
  MAINTAINERS: Add arm-soc tree entry
  ARM: dts: mxs: add the "clock-names" for gpmi-nand
  ARM: ux500: Correct SDI5 address and add some format changes
  ARM: ux500: Specify AMBA Primecell IDs for Nomadik I2C in DT
  ARM: ux500: Fix build error relating to IRQCHIP_SKIP_SET_WAKE
  ARM: at91: drop duplicated config SOC_AT91SAM9 entry
  ARM: at91/i2c: change id to let i2c-at91 work
  ARM: at91/i2c: change id to let i2c-gpio work
  ARM: at91/dts: at91sam9g20ek_common: Fix typos in buttons labels.
  ARM: at91: fix external interrupt specification in board code
  ARM: at91: fix external interrupts in non-DT case
  ARM: at91: at91sam9g10: fix SOC type detection
  ARM: at91/tc: fix typo in the DT document
  ARM: AM33XX: Fix configuration of dmtimer parent clock by dmtimer driverDate:Wed, 17 Oct 2012 13:55:55 -0500
  ...
2012-10-28 11:12:38 -07:00
David S. Miller
e9b9eb59ff sparc64: Use pause instruction when available.
In atomic backoff and cpu_relax(), use the pause instruction
found on SPARC-T4 and later.

It makes the cpu strand unselectable for the given number of
cycles, unless an intervening disrupting trap occurs.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-27 23:00:41 -07:00
David S. Miller
270c10e00a sparc64: Fix cpu strand yielding.
For atomic backoff, we just loop over an exponentially backed off
counter.  This is extremely ineffective as it doesn't actually yield
the cpu strand so that other competing strands can use the cpu core.

In cpus previous to SPARC-T4 we have to do this in a slightly hackish
way, by doing an operation with no side effects that also happens to
mark the strand as unavailable.

The mechanism we choose for this is three reads of the %ccr
(condition-code) register into %g0 (the zero register).

SPARC-T4 has an explicit "pause" instruction, and we'll make use of
that in a subsequent commit.

Yield strands also in cpu_relax().  We really should have done this a
very long time ago.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-27 18:35:27 -07:00
Arnd Bergmann
943bb48755 Revert "ARM i.MX25: Fix PWM per clock lookups"
This reverts commit 92063cee11, it
was applied prematurely, causing this build error for
imx_v4_v5_defconfig:

arch/arm/mach-imx/clk-imx25.c: In function 'mx25_clocks_init':
arch/arm/mach-imx/clk-imx25.c:206:26: error: 'pwm_ipg_per' undeclared (first use in this function)
arch/arm/mach-imx/clk-imx25.c:206:26: note: each undeclared identifier is reported only once for each function it appears in

Sascha Hauer explains:
> There are several gates missing in clk-imx25.c. I have a patch which
> adds support for them and I seem to have missed that the above depends
> on it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-10-27 17:46:56 +02:00
Arnd Bergmann
5b627ba0f5 ARM: versatile: fix versatile_defconfig
With the introduction of CONFIG_ARCH_MULTIPLATFORM, versatile is
no longer the default platform, so we need to enable
CONFIG_ARCH_VERSATILE explicitly in order for that to be selected
rather than the multiplatform configuration.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-10-27 17:46:56 +02:00
Thomas Petazzoni
e09348c757 ARM: mvebu: update defconfig with 3.7 changes
The split of 370 and XP into two Kconfig options and the multiplatform
kernel support has changed a few Kconfig symbols, so let's update the
mvebu_defconfig file with the latest changes.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2012-10-27 17:46:55 +02:00
Arnd Bergmann
0654f4ab2b ARM: at91: fix at91x40 build
patch 738a0fd7 "ARM: at91: fix external interrupts in non-DT case"
fixed a run-time error on some at91 platforms but did not apply
the same change to at91x40, which now doesn't build.

This changes at91x40 in the same way that the other platforms
were changed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
2012-10-27 17:46:48 +02:00
David S. Miller
517ffce4e1 sparc64: Make montmul/montsqr/mpmul usable in 32-bit threads.
The Montgomery Multiply, Montgomery Square, and Multiple-Precision
Multiply instructions work by loading a combination of the floating
point and multiple register windows worth of integer registers
with the inputs.

These values are 64-bit.  But for 32-bit userland processes we only
save the low 32-bits of each integer register during a register spill.
This is because the register window save area is in the user stack and
has a fixed layout.

Therefore, the only way to use these instruction in 32-bit mode is to
perform the following sequence:

1) Load the top-32bits of a choosen integer register with a sentinel,
   say "-1".  This will be in the outer-most register window.

   The idea is that we're trying to see if the outer-most register
   window gets spilled, and thus the 64-bit values were truncated.

2) Load all the inputs for the montmul/montsqr/mpmul instruction,
   down to the inner-most register window.

3) Execute the opcode.

4) Traverse back up to the outer-most register window.

5) Check the sentinel, if it's still "-1" store the results.
   Otherwise retry the entire sequence.

This retry is extremely troublesome.  If you're just unlucky and an
interrupt or other trap happens, it'll push that outer-most window to
the stack and clear the sentinel when we restore it.

We could retry forever and never make forward progress if interrupts
arrive at a fast enough rate (consider perf events as one example).
So we have do limited retries and fallback to software which is
extremely non-deterministic.

Luckily it's very straightforward to provide a mechanism to let
32-bit applications use a 64-bit stack.  Stacks in 64-bit mode are
biased by 2047 bytes, which means that the lowest bit is set in the
actual %sp register value.

So if we see bit zero set in a 32-bit application's stack we treat
it like a 64-bit stack.

Runtime detection of such a facility is tricky, and cumbersome at
best.  For example, just trying to use a biased stack and seeing if it
works is hard to recover from (the signal handler will need to use an
alt stack, plus something along the lines of longjmp).  Therefore, we
add a system call to report a bitmask of arch specific features like
this in a cheap and less hairy way.

With help from Andy Polyakov.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-26 15:18:37 -07:00
Linus Torvalds
6ad2c73d11 Serial fix for 3.7-rc3
Here is one patch, a revert of a omap serial driver patch that was causing
 problems, for your 3.7-rc tree.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull serial fix from Greg Kroah-Hartman:
 "Here is one patch, a revert of a omap serial driver patch that was
  causing problems, for your 3.7-rc tree.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'tty-3.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: omap: fix software flow control"
2012-10-26 10:26:08 -07:00