Commit Graph

111802 Commits

Author SHA1 Message Date
Linus Torvalds
eb63b34bdf Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS bug fixes from Ralf Baechle:
 "Two more fixes for 4.2.

  One fixes a build issue with the LLVM assembler - LLVM assembler macro
  names are case sensitive, GNU as macro names are insensitive; the
  other corrects a license string (GPL v2, not GPLv2) such that the
  module loader will recognice the license correctly"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  FIRMWARE: bcm47xx_nvram: Fix module license.
  MIPS: Fix LLVM build issue.
2015-08-23 07:23:09 -07:00
Linus Torvalds
b7dec838b5 Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
 "Another couple of small ARM fixes.

  A patch from Masahiro Yamada who noticed that "make -jN all zImage"
  would end up generating bad images where N > 1, and a patch from
  Nicolas to fix the Marvell CPU user access optimisation code when page
  faults are disabled"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8418/1: add boot image dependencies to not generate invalid images
  ARM: 8414/1: __copy_to_user_memcpy: fix mmap semaphore usage
2015-08-22 15:48:04 -07:00
Linus Torvalds
d0b89bd548 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Various low level fixes: fix more fallout from the FPU rework and the
  asm entry code rework, plus an MSI rework fix, and an idle-tracing fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu/math-emu: Fix crash in fork()
  x86/fpu/math-emu: Fix math-emu boot crash
  x86/idle: Restore trace_cpu_idle to mwait_idle() calls
  x86/irq: Build correct vector mapping for multiple MSI interrupts
  Revert "sched/x86_64: Don't save flags on context switch"
2015-08-22 08:15:36 -07:00
Linus Torvalds
84f3fe4608 Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "A series of small fixlets for a regression visible on OMAP devices
  caused by the conversion of the OMAP interrupt chips to hierarchical
  interrupt domains.  Mostly one liners on the driver side plus a small
  helper function in the core to avoid open coded mess in the drivers"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/crossbar: Restore set_wake functionality
  irqchip/crossbar: Restore the mask on suspend behaviour
  ARM: OMAP: wakeupgen: Restore the irq_set_type() mechanism
  irqchip/crossbar: Restore the irq_set_type() mechanism
  genirq: Introduce irq_chip_set_type_parent() helper
  genirq: Don't return ENOSYS in irq_chip_retrigger_hierarchy
2015-08-22 07:45:36 -07:00
Ingo Molnar
827409b2f5 x86/fpu/math-emu: Fix crash in fork()
During later stages of math-emu bootup the following crash triggers:

	 math_emulate: 0060:c100d0a8
	 Kernel panic - not syncing: Math emulation needed in kernel
	 CPU: 0 PID: 1511 Comm: login Not tainted 4.2.0-rc7+ #1012
	 [...]
	 Call Trace:
	  [<c181d50d>] dump_stack+0x41/0x52
	  [<c181c918>] panic+0x77/0x189
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c164c2d7>] math_emulate+0xba7/0xbd0
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c1109c3c>] ? __alloc_pages_nodemask+0x12c/0x870
	  [<c136ac20>] ? proc_clear_tty+0x40/0x70
	  [<c136ac6e>] ? session_clear_tty+0x1e/0x30
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c1003575>] do_device_not_available+0x45/0x70
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c18258e6>] error_code+0x5a/0x60
	  [<c1003530>] ? math_error+0x140/0x140
	  [<c100d0a8>] ? fpu__copy+0x138/0x1c0
	  [<c100c205>] arch_dup_task_struct+0x25/0x30
	  [<c1048cea>] copy_process.part.51+0xea/0x1480
	  [<c115a8e5>] ? dput+0x175/0x200
	  [<c136af70>] ? no_tty+0x30/0x30
	  [<c1157242>] ? do_vfs_ioctl+0x322/0x540
	  [<c104a21a>] _do_fork+0xca/0x340
	  [<c1057b06>] ? SyS_rt_sigaction+0x66/0x90
	  [<c104a557>] SyS_clone+0x27/0x30
	  [<c1824a80>] sysenter_do_call+0x12/0x12

The reason is the incorrect assumption in fpu_copy(), that FNSAVE
can be executed from math-emu kernels as well.

Don't try to copy the registers, the soft state will be copied
by fork anyway, so the child task inherits the parent task's
soft math state.

With this fix applied math-emu kernels boot up fine on modern
hardware and the 'no387 nofxsr' boot options.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-22 10:23:03 +02:00
Ingo Molnar
5fc960380e x86/fpu/math-emu: Fix math-emu boot crash
On a math-emu bootup the following crash occurs:

	Initializing CPU#0
	------------[ cut here ]------------
	kernel BUG at arch/x86/kernel/traps.c:779!
	invalid opcode: 0000 [#1] SMP
	[...]
	EIP is at do_device_not_available+0xe/0x70
	[...]
	Call Trace:
	 [<c18238e6>] error_code+0x5a/0x60
	 [<c1002bd0>] ? math_error+0x140/0x140
	 [<c100bbd9>] ? fpu__init_cpu+0x59/0xa0
	 [<c1012322>] cpu_init+0x202/0x330
	 [<c104509f>] ? __native_set_fixmap+0x1f/0x30
	 [<c1b56ab0>] trap_init+0x305/0x346
	 [<c1b548af>] start_kernel+0x1a5/0x35d
	 [<c1b542b4>] i386_start_kernel+0x82/0x86

The reason is that in the following commit:

  b1276c48e9 ("x86/fpu: Initialize fpregs in fpu__init_cpu_generic()")

I failed to consider math-emu's limitation that it cannot execute the
FNINIT instruction in kernel mode.

The long term fix might be to allow math-emu to execute (certain) kernel
mode FPU instructions, but for now apply the safe (albeit somewhat ugly)
fix: initialize the emulation state explicitly without trapping out to
the FPU emulator.

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-22 10:02:04 +02:00
Jisheng Zhang
e43d0189ac x86/idle: Restore trace_cpu_idle to mwait_idle() calls
Commit b253149b84 ("sched/idle/x86: Restore mwait_idle() to fix boot
hangs, to improve power savings and to improve performance") restores
mwait_idle(), but the trace_cpu_idle related calls are missing. This
causes powertop on my old desktop powered by Intel Core2 E6550 to
report zero wakeups and zero events.

Add them back to restore the proper behaviour.

Fixes: b253149b84 ("sched/idle/x86: Restore mwait_idle() to ...")
Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
Cc: <len.brown@intel.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1440046479-4262-1-git-send-email-jszhang@marvell.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-20 21:37:45 +02:00
Linus Torvalds
3d3e66ba2c xen: build fix for 4.2-rc7
- Fix i386 build with an (uncommon) configuration
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Merge tag 'for-linus-4.2-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen build fix from David Vrabel:
 "Fix i386 build with an (uncommon) configuration"

* tag 'for-linus-4.2-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC
2015-08-20 12:21:26 -07:00
David Vrabel
87ffd2b9bb x86/xen: make CONFIG_XEN depend on CONFIG_X86_LOCAL_APIC
Since commit feb44f1f7a (x86/xen:
Provide a "Xen PV" APIC driver to support >255 VCPUs) Xen guests need
a full APIC driver and thus should depend on X86_LOCAL_APIC.

This fixes an i386 build failure with !SMP && !CONFIG_X86_UP_APIC by
disabling Xen support in this configuration.

Users needing Xen support in a non-SMP i386 kernel will need to enable
CONFIG_X86_UP_APIC.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
2015-08-20 11:45:43 +01:00
Grygorii Strashko
63059a2723 ARM: OMAP: wakeupgen: Restore the irq_set_type() mechanism
The conversion of the wakeupgen irqchip to hierarchical irq domains
failed to provide a mechanism to properly set the trigger type of an
interrupt.

The wakeupgen irq chip itself has no mechanism and therefor no
irq_set_type() callback. The code before the conversion relayed the
trigger configuration directly to the underlying GIC.

Restore the correct behaviour by setting the wakeupgen irq_set_type
callback to irq_chip_set_type_parent(). This propagates the
set_trigger() call to the underlying GIC irqchip.

[ tglx: Massaged changelog ]

Fixes: 7136d457f3 ('ARM: omap: convert wakeupgen to stacked domains')
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: <linux@arm.linux.org.uk>
Cc: <nsekhar@ti.com>
Cc: <jason@lakedaemon.net>
Cc: <balbi@ti.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1439554830-19502-5-git-send-email-grygorii.strashko@ti.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-20 00:25:25 +02:00
Ingo Molnar
b5be5b7fff Merge branch 'x86/asm/urgent' to pick up an entry code fix
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-19 09:05:15 +02:00
Jiang Liu
527f0a91e9 x86/irq: Build correct vector mapping for multiple MSI interrupts
Alex Deucher, Mark Rustad and Alexander Holler reported a regression
with the latest v4.2-rc4 kernel, which breaks some SATA controllers.
With multi-MSI capable SATA controllers, only the first port works,
all other ports time out when executing SATA commands.

This happens because the first argument to assign_irq_vector_policy()
is always the base linux irq number of the multi MSI interrupt block,
so all subsequent vector assignments operate on the base linux irq
number, so all MSI irqs are handled as the first irq number. Therefor
the other MSI irqs of a device are never set up correctly and never
fire.

Add the loop iterator to the base irq number so all vectors are
assigned correctly.

Fixes: b5dc8e6c21 "x86/irq: Use hierarchical irqdomain to manage CPU interrupt vectors"
Reported-and-tested-by: Alex Deucher <alexdeucher@gmail.com>
Reported-and-tested-by: Mark Rustad <mrustad@gmail.com>
Reported-and-tested-by: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/1439911228-9880-1-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-08-18 18:18:55 +02:00
Masahiro Yamada
3939f33450 ARM: 8418/1: add boot image dependencies to not generate invalid images
U-Boot is often used to boot the kernel on ARM boards, but uImage
is not built by "make all", so we are often inclined to do
"make all uImage" to generate DTBs, modules and uImage in a single
command, but we should notice a pitfall behind it.  In fact,
"make all uImage" could generate an invalid uImage if it is run with
the parallel option (-j).

You can reproduce this problem with the following procedure:

[1] First, build "all" and "uImage" separately.
    You will get a valid uImage

  $ git clean -f -x -d
  $ export CROSS_COMPILE=<your-tools-prefix>
  $ make -s -j8 ARCH=arm multi_v7_defconfig
  $ make -s -j8 ARCH=arm all
  $ make -j8 ARCH=arm UIMAGE_LOADADDR=0x80208000 uImage
    CHK     include/config/kernel.release
    CHK     include/generated/uapi/linux/version.h
    CHK     include/generated/utsrelease.h
  make[1]: `include/generated/mach-types.h' is up to date.
    CHK     include/generated/timeconst.h
    CHK     include/generated/bounds.h
    CHK     include/generated/asm-offsets.h
    CALL    scripts/checksyscalls.sh
    CHK     include/generated/compile.h
    Kernel: arch/arm/boot/Image is ready
    Kernel: arch/arm/boot/zImage is ready
    UIMAGE  arch/arm/boot/uImage
  Image Name:   Linux-4.2.0-rc5-00156-gdd2384a-d
  Created:      Sat Aug  8 23:21:35 2015
  Image Type:   ARM Linux Kernel Image (uncompressed)
  Data Size:    6138648 Bytes = 5994.77 kB = 5.85 MB
  Load Address: 80208000
  Entry Point:  80208000
    Image arch/arm/boot/uImage is ready
  $ ls -l arch/arm/boot/*Image
  -rwxrwxr-x 1 masahiro masahiro 13766656 Aug  8 23:20 arch/arm/boot/Image
  -rw-rw-r-- 1 masahiro masahiro  6138712 Aug  8 23:21 arch/arm/boot/uImage
  -rwxrwxr-x 1 masahiro masahiro  6138648 Aug  8 23:20 arch/arm/boot/zImage

[2] Update some source file(s)

  $ touch init/main.c

[3] Then, re-build "all" and "uImage" simultaneously.
    You will get an invalid uImage at random.

  $ make -j8 ARCH=arm UIMAGE_LOADADDR=0x80208000 all uImage
    CHK     include/config/kernel.release
    CHK     include/generated/uapi/linux/version.h
    CHK     include/generated/utsrelease.h
  make[1]: `include/generated/mach-types.h' is up to date.
    CHK     include/generated/timeconst.h
    CHK     include/generated/bounds.h
    CHK     include/generated/asm-offsets.h
    CALL    scripts/checksyscalls.sh
    CC      init/main.o
    CHK     include/generated/compile.h
    LD      init/built-in.o
    LINK    vmlinux
    LD      vmlinux.o
    MODPOST vmlinux.o
    GEN     .version
    CHK     include/generated/compile.h
    UPD     include/generated/compile.h
    CC      init/version.o
    LD      init/built-in.o
    KSYM    .tmp_kallsyms1.o
    KSYM    .tmp_kallsyms2.o
    LD      vmlinux
    SORTEX  vmlinux
    SYSMAP  System.map
    OBJCOPY arch/arm/boot/Image
    Building modules, stage 2.
    Kernel: arch/arm/boot/Image is ready
    GZIP    arch/arm/boot/compressed/piggy.gzip
    AS      arch/arm/boot/compressed/piggy.gzip.o
    Kernel: arch/arm/boot/Image is ready
    LD      arch/arm/boot/compressed/vmlinux
    GZIP    arch/arm/boot/compressed/piggy.gzip
    OBJCOPY arch/arm/boot/zImage
    Kernel: arch/arm/boot/zImage is ready
    UIMAGE  arch/arm/boot/uImage
  Image Name:   Linux-4.2.0-rc5-00156-gdd2384a-d
  Created:      Sat Aug  8 23:23:14 2015
  Image Type:   ARM Linux Kernel Image (uncompressed)
  Data Size:    26472 Bytes = 25.85 kB = 0.03 MB
  Load Address: 80208000
  Entry Point:  80208000
    Image arch/arm/boot/uImage is ready
    MODPOST 192 modules
    AS      arch/arm/boot/compressed/piggy.gzip.o
    LD      arch/arm/boot/compressed/vmlinux
    OBJCOPY arch/arm/boot/zImage
    Kernel: arch/arm/boot/zImage is ready
  $ ls -l arch/arm/boot/*Image
  -rwxrwxr-x 1 masahiro masahiro 13766656 Aug  8 23:23 arch/arm/boot/Image
  -rw-rw-r-- 1 masahiro masahiro    26536 Aug  8 23:23 arch/arm/boot/uImage
  -rwxrwxr-x 1 masahiro masahiro  6138648 Aug  8 23:23 arch/arm/boot/zImage

Please notice the uImage is extremely small when this issue is
encountered.  Besides, "Kernel: arch/arm/boot/zImage is ready" is
displayed twice, before and after the uImage log.

The root cause of this is the race condition between zImage and
uImage.  Actually, uImage depends on zImage, but the dependency
between the two is only described in arch/arm/boot/Makefile.
Because arch/arm/boot/Makefile is not included from the top-level
Makefile, it cannot know the dependency between zImage and uImage.

Consequently, when we run make with the parallel option, Kbuild
updates vmlinux first, and then two different threads descends into
the arch/arm/boot/Makefile almost at the same time, one for updating
zImage and the other for uImage.  While one thread is re-generating
zImage, the other also tries to update zImage before creating uImage
on top of that.  zImage is overwritten by the slower thread and then
uImage is created based on the half-written zImage.

This is the reason why "Kernel: arch/arm/boot/zImage is ready" is
displayed twice, and a broken uImage is created.

The same problem could happen on bootpImage.

This commit adds dependencies among Image, zImage, uImage, and
bootpImage to arch/arm/Makefile, which is included from the
top-level Makefile.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-18 13:59:59 +01:00
Nicolas Pitre
0f64b247e6 ARM: 8414/1: __copy_to_user_memcpy: fix mmap semaphore usage
The mmap semaphore should not be taken when page faults are disabled.
Since pagefault_disable() no longer disables preemption, we now need
to use faulthandler_disabled() in place of in_atomic().

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-18 13:59:59 +01:00
Ralf Baechle
158d3b2ad1 MIPS: Fix LLVM build issue.
Matthew Fortune <Matthew.Fortune@imgtec.com> reports:

The genex.S file appears to mix the case of a macro between its definition and
use. A cut down example of this is below. The macro __build_clear_none has
lower case 'build' but ends up being instantiated with upper case BUILD. Can
this be fixed on master. It has been picked up by the LLVM integrated assembler
which is currently case sensitive. We are likely to fix the assembler as well
but the code is currently inconsistent in the kernel.

 .macro __build_clear_none
 .endm

 .macro __BUILD_HANDLER exception handler clear verbose ext
 .align 5
 .globl handle_\exception; .align 2; .type handle_\exception, @function; .ent
handle_\exception, 0; handle_\exception: .frame $29, 184, $29
 .set noat
 .globl handle_\exception\ext; .type handle_\exception\ext, @function;
handle_\exception\ext:
 __BUILD_clear_\clear
 .endm

 .macro BUILD_HANDLER exception handler clear verbose
 __BUILD_HANDLER \exception \handler \clear \verbose _int
 .endm

BUILD_HANDLER ftlb ftlb none silent

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported-by: Matthew Fortune <Matthew.Fortune@imgtec.com>
2015-08-18 11:40:20 +02:00
Andy Lutomirski
512255a2ad Revert "sched/x86_64: Don't save flags on context switch"
This reverts commit:

  2c7577a758 ("sched/x86_64: Don't save flags on context switch")

It was a nice speedup.  It's also not quite correct: SYSENTER
enables interrupts too early.

We can re-add this optimization once the SYSENTER code is beaten
into shape, which should happen in 4.3 or 4.4.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # v3.19
Link: http://lkml.kernel.org/r/85f56651f59f76624e80785a8fd3bdfdd089a818.1439838962.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-18 09:39:26 +02:00
Linus Torvalds
8916e0b03e ARM: SoC fixes
A smallish batch of fixes, a little more than expected this late, but
 all fixes are contained to their platforms and seem reasonably low risk:
 
 - A somewhat large SMP fix for ux500 that still seemed warranted to include here
 - OMAP DT fixes for pbias regulator specification that broke due to some DT
   reshuffling
 - PCIe IRQ routing bugfix for i.MX
 - Networking fixes for keystone
 - Runtime PM for OMAP GPMC
 - A couple of error path bug fixes for exynos
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Merge tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC fixes from Olof Johansson:
 "A smallish batch of fixes, a little more than expected this late, but
  all fixes are contained to their platforms and seem reasonably low
  risk:

   - a somewhat large SMP fix for ux500 that still seemed warranted to
     include here
   - OMAP DT fixes for pbias regulator specification that broke due to
     some DT reshuffling
   - PCIe IRQ routing bugfix for i.MX
   - networking fixes for keystone
   - runtime PM for OMAP GPMC
   - a couple of error path bug fixes for exynos"

* tag 'armsoc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file
  ARM: dts: keystone: fix the clock node for mdio
  memory: omap-gpmc: Don't try to save uninitialized GPMC context
  ARM: imx6: correct i.MX6 PCIe interrupt routing
  ARM: ux500: add an SMP enablement type and move cpu nodes
  ARM: dts: dra7: Fix broken pbias device creation
  ARM: dts: OMAP5: Fix broken pbias device creation
  ARM: dts: OMAP4: Fix broken pbias device creation
  ARM: dts: omap243x: Fix broken pbias device creation
  ARM: EXYNOS: fix double of_node_put() on error path
  ARM: EXYNOS: Fix potentian kfree() of ro memory
2015-08-16 15:44:33 -07:00
Linus Torvalds
0f405bf75f Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS bugfix from Ralf Baechle:
 "Only a single MIPS fix - the math when invoking syscall_trace_enter
  was wrong"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Fix seccomp syscall argument for MIPS64
2015-08-16 15:39:31 -07:00
Linus Torvalds
01565479e9 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Merge x86 fixes from Ingo Molnar:
 "Two followup fixes related to the previous LDT fix"

Also applied a further FPU emulation fix from Andy Lutomirski to the
branch before actually merging it.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
  x86/ldt: Further fix FPU emulation
  x86/ldt: Correct FPU emulation access to LDT
  x86/ldt: Correct LDT access in single stepping logic
2015-08-16 15:11:25 -07:00
Andy Lutomirski
12e244f4b5 x86/ldt: Further fix FPU emulation
The previous fix confused a selector with a segment prefix.  Fix it.

Compile-tested only.

Cc: stable@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes: 4809146b86 ("x86/ldt: Correct FPU emulation access to LDT")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-16 15:11:05 -07:00
Olof Johansson
02149517ac ARM: Couple of Keysyone MDIO DTS fixes for 4.2-rc6+
These are necessary to get the NIC card working on all Keystone
 EVMs. Couple of boards are nroken without these two fixes.
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Merge tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone into fixes

ARM: Couple of Keysyone MDIO DTS fixes for 4.2-rc6+

These are necessary to get the NIC card working on all Keystone
EVMs. Couple of boards are broken without these two fixes.

* tag 'keystone-dts-late-fixes-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/ssantosh/linux-keystone:
  ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file
  ARM: dts: keystone: fix the clock node for mdio

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-08-16 21:29:57 +02:00
Markos Chandras
9f161439e4 MIPS: Fix seccomp syscall argument for MIPS64
Commit 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls (o32)")
fixed indirect system calls on O32 but it also introduced a bug for MIPS64
where it erroneously modified the v0 (syscall) register with the assumption
that the sycall offset hasn't been taken into consideration. This breaks
seccomp on MIPS64 n64 and n32 ABIs. We fix this by replacing the addition
with a move instruction.

Fixes: 4c21b8fd8f ("MIPS: seccomp: Handle indirect system calls (o32)")
Cc: <stable@vger.kernel.org> # 3.15+
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10951/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-08-16 15:00:59 +02:00
Linus Torvalds
45e38cff4f Just two very small & simple patches.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "Just two very small & simple patches"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST
  KVM: x86: zero IDT limit on entry to SMM
2015-08-14 17:27:52 -07:00
Linus Torvalds
b25c6cee55 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "Misc fixes: PMU driver corner cases, tooling fixes, and an 'AUX'
  (Intel PT) race related core fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler
  perf/x86/intel: Fix memory leak on hot-plug allocation fail
  perf: Fix PERF_EVENT_IOC_PERIOD migration race
  perf: Fix double-free of the AUX buffer
  perf: Fix fasync handling on inherited events
  perf tools: Fix test build error when bindir contains double slash
  perf stat: Fix transaction lenght metrics
  perf: Fix running time accounting
2015-08-14 10:57:16 -07:00
Linus Torvalds
7ddab73346 Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
 "Another few small ARM fixes, mostly addressing some VDSO issues"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8410/1: VDSO: fix coarse clock monotonicity regression
  ARM: 8409/1: Mark ret_fast_syscall as a function
  ARM: 8408/1: Fix the secondary_startup function in Big Endian case
  ARM: 8405/1: VDSO: fix regression with toolchains lacking ld.bfd executable
2015-08-13 16:34:56 -07:00
Linus Torvalds
cd88ec2317 x86: fix error handling for 32-bit compat out-of-range system call numbers
Commit 3f5159a922 ("x86/asm/entry/32: Update -ENOSYS handling to match
the 64-bit logic") broke the ENOSYS handling for the 32-bit compat case.
The proper error return value was never loaded into %rax, except if
things just happened to go through the audit paths, which ended up
reloading the return value.

This moves the loading or %rax into the normal system call path, just to
make sure the error case triggers it.  It's kind of sad, since it adds a
useless instruction to reload the register to the fast path, but it's
not like that single load from the stack is going to be noticeable.

Reported-by: David Drysdale <drysdale@google.com>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-13 16:19:44 -07:00
Linus Torvalds
6b476e1140 xen: bug fixes for 4.2-rc6
- Revert a fix from 4.2-rc5 that was causing lots of WARNING spam.
 - Fix a memory leak affecting backends in HVM guests.
 - Fix PV domU hang with certain configurations.
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Merge tag 'for-linus-4.2-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel:

 - revert a fix from 4.2-rc5 that was causing lots of WARNING spam.

 - fix a memory leak affecting backends in HVM guests.

 - fix PV domU hang with certain configurations.

* tag 'for-linus-4.2-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/xenbus: Don't leak memory when unmapping the ring on HVM backend
  Revert "xen/events/fifo: Handle linked events when closing a port"
  x86/xen: build "Xen PV" APIC driver for domU as well
2015-08-13 13:36:22 -07:00
Linus Torvalds
ed596cde94 Revert x86 sigcontext cleanups
This reverts commits 9a036b93a3 ("x86/signal/64: Remove 'fs' and 'gs'
from sigcontext") and c6f2062935 ("x86/signal/64: Fix SS handling for
signals delivered to 64-bit programs").

They were cleanups, but they break dosemu by changing the signal return
behavior (and removing 'fs' and 'gs' from the sigcontext struct - while
not actually changing any behavior - causes build problems).

Reported-and-tested-by: Stas Sergeev <stsp@list.ru>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-13 12:42:22 -07:00
Murali Karicheri
85ad3deea4 ARM: dts: keystone: Fix the mdio bindings by moving it to soc specific file
Currently mdio bindings are defined in keystone.dtsi and this results
in incorrect unit address for the node on K2E and K2L SoCs. Fix this
by moving them to SoC specific DTS file.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
2015-08-13 10:01:29 -07:00
Murali Karicheri
e61eee7cf8 ARM: dts: keystone: fix the clock node for mdio
Currently the MDIO clock is pointing to clkpa instead of clkcpgmac.
MDIO is part of the ethss and the clock should be clkcpgmac.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
2015-08-13 10:01:29 -07:00
Olof Johansson
db55350599 The i.MX fixes for 4.2, 3rd round:
- Fix i.MX6 PCIe interrupt routing which gets missed from stacked IRQ
    domain conversion.  The PCIe wakeup support is currently broken
    because of this.
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Merge tag 'imx-fixes-4.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux into fixes

The i.MX fixes for 4.2, 3rd round:
 - Fix i.MX6 PCIe interrupt routing which gets missed from stacked IRQ
   domain conversion.  The PCIe wakeup support is currently broken
   because of this.

* tag 'imx-fixes-4.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux:
  ARM: imx6: correct i.MX6 PCIe interrupt routing

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-08-13 12:24:55 +02:00
Olof Johansson
07616f013b Two fixes for bugs in Exynos power domain error exit path:
1. kfree() of read-only memory (name of power domain returned
    by kstrdup_const()),
 2. Doubled of_node_put() leading to invalid ref count for OF node.
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Merge tag 'samsung-mach-fixes-4.2' of https://github.com/krzk/linux into fixes

Two fixes for bugs in Exynos power domain error exit path:
1. kfree() of read-only memory (name of power domain returned
   by kstrdup_const()),
2. Doubled of_node_put() leading to invalid ref count for OF node.

* tag 'samsung-mach-fixes-4.2' of https://github.com/krzk/linux:
  ARM: EXYNOS: fix double of_node_put() on error path
  ARM: EXYNOS: Fix potentian kfree() of ro memory

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-08-13 12:18:45 +02:00
Matt Fleming
d7a702f0b1 perf/x86/intel/cqm: Do not access cpu_data() from CPU_UP_PREPARE handler
Tony reports that booting his 144-cpu machine with maxcpus=10 triggers
the following WARN_ON():

[   21.045727] WARNING: CPU: 8 PID: 647 at arch/x86/kernel/cpu/perf_event_intel_cqm.c:1267 intel_cqm_cpu_prepare+0x75/0x90()
[   21.045744] CPU: 8 PID: 647 Comm: systemd-udevd Not tainted 4.2.0-rc4 #1
[   21.045745] Hardware name: Intel Corporation BRICKLAND/BRICKLAND, BIOS BRHSXSD1.86B.0066.R00.1506021730 06/02/2015
[   21.045747]  0000000000000000 0000000082771b09 ffff880856333ba8 ffffffff81669b67
[   21.045748]  0000000000000000 0000000000000000 ffff880856333be8 ffffffff8107b02a
[   21.045750]  ffff88085b789800 ffff88085f68a020 ffffffff819e2470 000000000000000a
[   21.045750] Call Trace:
[   21.045757]  [<ffffffff81669b67>] dump_stack+0x45/0x57
[   21.045759]  [<ffffffff8107b02a>] warn_slowpath_common+0x8a/0xc0
[   21.045761]  [<ffffffff8107b15a>] warn_slowpath_null+0x1a/0x20
[   21.045762]  [<ffffffff81036725>] intel_cqm_cpu_prepare+0x75/0x90
[   21.045764]  [<ffffffff81036872>] intel_cqm_cpu_notifier+0x42/0x160
[   21.045767]  [<ffffffff8109a33d>] notifier_call_chain+0x4d/0x80
[   21.045769]  [<ffffffff8109a44e>] __raw_notifier_call_chain+0xe/0x10
[   21.045770]  [<ffffffff8107b538>] _cpu_up+0xe8/0x190
[   21.045771]  [<ffffffff8107b65a>] cpu_up+0x7a/0xa0
[   21.045774]  [<ffffffff8165e920>] cpu_subsys_online+0x40/0x90
[   21.045777]  [<ffffffff81433b37>] device_online+0x67/0x90
[   21.045778]  [<ffffffff81433bea>] online_store+0x8a/0xa0
[   21.045782]  [<ffffffff81430e78>] dev_attr_store+0x18/0x30
[   21.045785]  [<ffffffff8126b6ba>] sysfs_kf_write+0x3a/0x50
[   21.045786]  [<ffffffff8126ad40>] kernfs_fop_write+0x120/0x170
[   21.045789]  [<ffffffff811f0b77>] __vfs_write+0x37/0x100
[   21.045791]  [<ffffffff811f38b8>] ? __sb_start_write+0x58/0x110
[   21.045795]  [<ffffffff81296d2d>] ? security_file_permission+0x3d/0xc0
[   21.045796]  [<ffffffff811f1279>] vfs_write+0xa9/0x190
[   21.045797]  [<ffffffff811f2075>] SyS_write+0x55/0xc0
[   21.045800]  [<ffffffff81067300>] ? do_page_fault+0x30/0x80
[   21.045804]  [<ffffffff816709ae>] entry_SYSCALL_64_fastpath+0x12/0x71
[   21.045805] ---[ end trace fe228b836d8af405 ]---

The root cause is that CPU_UP_PREPARE is completely the wrong notifier
action from which to access cpu_data(), because smp_store_cpu_info()
won't have been executed by the target CPU at that point, which in turn
means that ->x86_cache_max_rmid and ->x86_cache_occ_scale haven't been
filled out.

Instead let's invoke our handler from CPU_STARTING and rename it
appropriately.

Reported-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vikas Shivappa <vikas.shivappa@intel.com>
Link: http://lkml.kernel.org/r/1438863163-14083-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:37:23 +02:00
Peter Zijlstra
dbc72b7a0c perf/x86/intel: Fix memory leak on hot-plug allocation fail
We fail to free the shared_regs allocation if the constraint_list
allocation fails.

Cure this and be more consistent in NULL-ing the pointers after free.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-12 11:37:22 +02:00
Olof Johansson
e2e927c823 Few trivial omap MMC regression fixes for card voltages where
the syscon areas for PBIAS regulator were missing "simple-bus"
 that prevents probing of the children in the mapped region.
 
 This probably was not noticed earlier as the bootloader has
 already configured the regulator for the card in the slot.
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Merge tag 'omap-for-v4.2/fixes-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

Few trivial omap MMC regression fixes for card voltages where
the syscon areas for PBIAS regulator were missing "simple-bus"
that prevents probing of the children in the mapped region.

This probably was not noticed earlier as the bootloader has
already configured the regulator for the card in the slot.

* tag 'omap-for-v4.2/fixes-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: dts: dra7: Fix broken pbias device creation
  ARM: dts: OMAP5: Fix broken pbias device creation
  ARM: dts: OMAP4: Fix broken pbias device creation
  ARM: dts: omap243x: Fix broken pbias device creation

Signed-off-by: Olof Johansson <olof@lixom.net>
2015-08-11 15:22:10 +02:00
Nathan Lynch
09edea4f8f ARM: 8410/1: VDSO: fix coarse clock monotonicity regression
Since 906c55579a ("timekeeping: Copy the shadow-timekeeper over the
real timekeeper last") it has become possible on ARM to:

- Obtain a CLOCK_MONOTONIC_COARSE or CLOCK_REALTIME_COARSE timestamp
  via syscall.
- Subsequently obtain a timestamp for the same clock ID via VDSO which
  predates the first timestamp (by one jiffy).

This is because ARM's update_vsyscall is deriving the coarse time
using the __current_kernel_time interface, when it should really be
using the timekeeper object provided to it by the timekeeping core.
It happened to work before only because __current_kernel_time would
access the same timekeeper object which had been passed to
update_vsyscall.  This is no longer the case.

Cc: stable@vger.kernel.org
Fixes: 906c55579a ("timekeeping: Copy the shadow-timekeeper over the real timekeeper last")
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-11 13:42:44 +01:00
Nathan Lynch
878854a374 arm64: VDSO: fix coarse clock monotonicity regression
Since 906c55579a ("timekeeping: Copy the shadow-timekeeper over the
real timekeeper last") it has become possible on arm64 to:

- Obtain a CLOCK_MONOTONIC_COARSE or CLOCK_REALTIME_COARSE timestamp
  via syscall.
- Subsequently obtain a timestamp for the same clock ID via VDSO which
  predates the first timestamp (by one jiffy).

This is because arm64's update_vsyscall is deriving the coarse time
using the __current_kernel_time interface, when it should really be
using the timekeeper object provided to it by the timekeeping core.
It happened to work before only because __current_kernel_time would
access the same timekeeper object which had been passed to
update_vsyscall.  This is no longer the case.

Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-08-10 15:37:45 +01:00
Jason A. Donenfeld
fc5fee86bd x86/xen: build "Xen PV" APIC driver for domU as well
It turns out that a PV domU also requires the "Xen PV" APIC
driver. Otherwise, the flat driver is used and we get stuck in busy
loops that never exit, such as in this stack trace:

(gdb) target remote localhost:9999
Remote debugging using localhost:9999
__xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
56              while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
(gdb) bt
 #0  __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
 #1  __default_send_IPI_shortcut (shortcut=<optimized out>,
dest=<optimized out>, vector=<optimized out>) at
./arch/x86/include/asm/ipi.h:75
 #2  apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54
 #3  0xffffffff81011336 in arch_irq_work_raise () at
arch/x86/kernel/irq_work.c:47
 #4  0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at
kernel/irq_work.c:100
 #5  0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633
 #6  0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized
out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>,
fmt=<optimized out>, args=<optimized out>)
    at kernel/printk/printk.c:1778
 #7  0xffffffff816010c8 in printk (fmt=<optimized out>) at
kernel/printk/printk.c:1868
 #8  0xffffffffc00013ea in ?? ()
 #9  0x0000000000000000 in ?? ()

Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-10 15:33:10 +01:00
Linus Torvalds
3fbdc37956 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS fixes from Ralf Baechle:
 "Another round of MIPS fixes for 4.2.  No area does particularly stand
  out but we have a two unpleasant ones:

   - Kernel ptes are marked with a global bit which allows the kernel to
     share kernel TLB entries between all processes.  For this to work
     both entries of an adjacent even/odd pte pair need to have the
     global bit set.  There has been a subtle race in setting the other
     entry's global bit since ~ 2000 but it take particularly
     pathological workloads that essentially do mostly vmalloc/vfree to
     trigger this.

     This pull request fixes the 64-bit case but leaves the case of 32
     bit CPUs with 64 bit ptes unsolved for now.  The unfixed cases
     affect hardware that is not available in the field yet.

   - Instruction emulation requires loading instructions from user space
     but the current fast but simplistic approach will fail on pages
     that are PROT_EXEC but !PROT_READ.  For this reason we temporarily
     do not permit this permission and will map pages with PROT_EXEC |
     PROT_READ.

  The remainder of this pull request is more or less across the field
  and the short log explains them well"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Make set_pte() SMP safe.
  MIPS: Replace add and sub instructions in relocate_kernel.S with addiu
  MIPS: Flush RPS on kernel entry with EVA
  Revert "MIPS: BCM63xx: Provide a plat_post_dma_flush hook"
  MIPS: BMIPS: Delete unused Kconfig symbol
  MIPS: Export get_c0_perfcount_int()
  MIPS: show_stack: Fix stack trace with EVA
  MIPS: do_mcheck: Fix kernel code dump with EVA
  MIPS: SMP: Don't increment irq_count multiple times for call function IPIs
  MIPS: Partially disable RIXI support.
  MIPS: Handle page faults of executable but unreadable pages correctly.
  MIPS: Malta: Don't reinitialise RTC
  MIPS: unaligned: Fix build error on big endian R6 kernels
  MIPS: Fix sched_getaffinity with MT FPAFF enabled
  MIPS: Fix build with CONFIG_OF=y for non OF-enabled targets
  CPUFREQ: Loongson2: Fix broken build due to incorrect include.
2015-08-09 05:59:21 +03:00
Juergen Gross
4809146b86 x86/ldt: Correct FPU emulation access to LDT
Commit 37868fe113 ("x86/ldt: Make modify_ldt synchronous")
introduced a new struct ldt_struct anchored at mm->context.ldt.

Adapt the x86 fpu emulation code to use that new structure.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: <stable@vger.kernel.org> # On top of: 37868fe113: x86/ldt: Make modify_ldt synchronous
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: billm@melbpc.org.au
Link: http://lkml.kernel.org/r/1438883674-1240-1-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-08 10:20:45 +02:00
Juergen Gross
136d9d83c0 x86/ldt: Correct LDT access in single stepping logic
Commit 37868fe113 ("x86/ldt: Make modify_ldt synchronous")
introduced a new struct ldt_struct anchored at mm->context.ldt.

convert_ip_to_linear() was changed to reflect this, but indexing
into the ldt has to be changed as the pointer is no longer void *.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: <stable@vger.kernel.org> # On top of: 37868fe113: x86/ldt: Make modify_ldt synchronous
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Link: http://lkml.kernel.org/r/1438848278-12906-1-git-send-email-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-08-08 10:20:45 +02:00
Linus Torvalds
dd2384a75d Enabling a reduced config of HS38 (w/o div-rem, ll64...)
Adding software workaround for LLOCK/SCOND livelock
 Fallout of a recent pt_regs update
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Merge tag 'arc-v4.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

Pull ARC fixes from Vineet Gupta:
 "Here's a late pull request for accumulated ARC fixes which came out of
  extended testing of the new ARCv2 port with LTP etc.  llock/scond
  livelock workaround has been reviewed by PeterZ.  The changes look a
  lot but I've crafted them into finer grained patches for better
  tracking later.

  I have some more fixes (ARC Futex backend) ready to go but those will
  have to wait for tglx to return from vacation.

  Summary:
   - Enable a reduced config of HS38 (w/o div-rem, ll64...)
   - Add software workaround for LLOCK/SCOND livelock
   - Fallout of a recent pt_regs update"

* tag 'arc-v4.2-rc6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential backoff
  ARC: Make pt_regs regs unsigned
  ARCv2: spinlock/rwlock: Reset retry delay when starting a new spin-wait cycle
  ARCv2: spinlock/rwlock/atomics: Delayed retry of failed SCOND with exponential backoff
  ARC: LLOCK/SCOND based rwlock
  ARC: LLOCK/SCOND based spin_lock
  ARC: refactor atomic inline asm operands with symbolic names
  Revert "ARCv2: STAR 9000837815 workaround hardware exclusive transactions livelock"
  ARCv2: [axs103_smp] Reduce clk for Quad FPGA configs
  ARCv2: Fix the peripheral address space detection
  ARCv2: allow selection of page size for MMUv4
  ARCv2: lib: memset: Don't assume 64-bit load/stores
  ARCv2: lib: memcpy: Missing PREFETCHW
  ARCv2: add knob for DIV_REV in Kconfig
  ARC/time: Migrate to new 'set-state' interface
2015-08-08 04:38:00 +03:00
Linus Torvalds
d5a8ab400b USB fixes for 4.2-rc6
Here are some USB and PHY fixes for 4.2-rc6 that resolve some reported
 issues.
 
 All of these have been in the linux-next tree for a while, full details
 on the patches are in the shortlog below.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are some USB and PHY fixes for 4.2-rc6 that resolve some reported
  issues.

  All of these have been in the linux-next tree for a while, full
  details on the patches are in the shortlog below"

* tag 'usb-4.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  ARM: dts: dra7: Add syscon-pllreset syscon to SATA PHY
  drivers/usb: Delete XHCI command timer if necessary
  xhci: fix off by one error in TRB DMA address boundary check
  usb: udc: core: add device_del() call to error pathway
  phy: ti-pipe3: i783 workaround for SATA lockup after dpll unlock/relock
  phy-sun4i-usb: Add missing EXPORT_SYMBOL_GPL for sun4i_usb_phy_set_squelch_detect
  USB: sierra: add 1199:68AB device ID
  usb: gadget: f_printer: actually limit the number of instances
  usb: gadget: f_hid: actually limit the number of instances
  usb: gadget: f_uac2: fix calculation of uac2->p_interval
  usb: gadget: bdc: fix a driver crash on disconnect
  usb: chipidea: ehci_init_driver is intended to call one time
  USB: qcserial: Add support for Dell Wireless 5809e 4G Modem
  USB: qcserial/option: make AT URCs work for Sierra Wireless MC7305/MC7355
2015-08-08 04:27:51 +03:00
Drew Richardson
e83dd37700 ARM: 8409/1: Mark ret_fast_syscall as a function
ret_fast_syscall runs when user space makes a syscall. However it
needs to be marked as such so the ELF information is correct. Before
it was:

   101: 8000f300     0 NOTYPE  LOCAL  DEFAULT    2 ret_fast_syscall

But with this change it correctly shows as:

   101: 8000f300    96 FUNC    LOCAL  DEFAULT    2 ret_fast_syscall

I see this function when using perf to unwind call stacks from kernel
space to user space. Without this change I would need to add some
special case logic when using the vmlinux ELF information.

Signed-off-by: Drew Richardson <drew.richardson@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-07 19:57:02 +01:00
Gregory CLEMENT
998ef5d81c ARM: 8408/1: Fix the secondary_startup function in Big Endian case
Since the commit "b2c3e38a5471 ARM: redo TTBR setup code for LPAE",
the setup code had been reworked. As a result the secondary CPUs
failed to come online in Big Endian.

As explained by Russell, the new code expected the value in r4/r5 to
be the least significant 32bits in r4 and the most significant 32bits
in r5. However, in the secondary code, we load this using ldrd, which
on BE reverses that.

This patch swap r4/r5 after the ldrd. It is done using the xor
instructions in order to not use a temporary register.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-08-07 19:57:02 +01:00
Haozhong Zhang
d7add05458 KVM: x86: Use adjustment in guest cycles when handling MSR_IA32_TSC_ADJUST
When kvm_set_msr_common() handles a guest's write to
MSR_IA32_TSC_ADJUST, it will calcuate an adjustment based on the data
written by guest and then use it to adjust TSC offset by calling a
call-back adjust_tsc_offset(). The 3rd parameter of adjust_tsc_offset()
indicates whether the adjustment is in host TSC cycles or in guest TSC
cycles. If SVM TSC scaling is enabled, adjust_tsc_offset()
[i.e. svm_adjust_tsc_offset()] will first scale the adjustment;
otherwise, it will just use the unscaled one. As the MSR write here
comes from the guest, the adjustment is in guest TSC cycles. However,
the current kvm_set_msr_common() uses it as a value in host TSC
cycles (by using true as the 3rd parameter of adjust_tsc_offset()),
which can result in an incorrect adjustment of TSC offset if SVM TSC
scaling is enabled. This patch fixes this problem.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Cc: stable@vger.linux.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-07 13:28:03 +02:00
Paolo Bonzini
18c3626e3d KVM: x86: zero IDT limit on entry to SMM
The recent BlackHat 2015 presentation "The Memory Sinkhole"
mentions that the IDT limit is zeroed on entry to SMM.

This is not documented, and must have changed some time after 2010
(see http://www.ssi.gouv.fr/uploads/IMG/pdf/IT_Defense_2010_final.pdf).
KVM was not doing it, but the fix is easy.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-07 12:46:32 +02:00
Vineet Gupta
1097163870 ARCv2: spinlock/rwlock/atomics: reduce 1 instruction in exponential backoff
The increment of delay counter was 2 instructions:
Arithmatic Shfit Left (ASL) + set to 1 on overflow

This can be done in 1 using ROtate Left (ROL)

Suggested-by: Nigel Topham <ntopham@synopsys.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-08-07 13:56:16 +05:30
Linus Torvalds
49d7c6559b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fix from David Miller:
 "FPU register corruption bug fix"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Fix userspace FPU register corruptions.
2015-08-07 05:28:24 +03:00
David S. Miller
44922150d8 sparc64: Fix userspace FPU register corruptions.
If we have a series of events from userpsace, with %fprs=FPRS_FEF,
like follows:

ETRAP
	ETRAP
		VIS_ENTRY(fprs=0x4)
		VIS_EXIT
		RTRAP (kernel FPU restore with fpu_saved=0x4)
	RTRAP

We will not restore the user registers that were clobbered by the FPU
using kernel code in the inner-most trap.

Traps allocate FPU save slots in the thread struct, and FPU using
sequences save the "dirty" FPU registers only.

This works at the initial trap level because all of the registers
get recorded into the top-level FPU save area, and we'll return
to userspace with the FPU disabled so that any FPU use by the user
will take an FPU disabled trap wherein we'll load the registers
back up properly.

But this is not how trap returns from kernel to kernel operate.

The simplest fix for this bug is to always save all FPU register state
for anything other than the top-most FPU save area.

Getting rid of the optimized inner-slot FPU saving code ends up
making VISEntryHalf degenerate into plain VISEntry.

Longer term we need to do something smarter to reinstate the partial
save optimizations.  Perhaps the fundament error is having trap entry
and exit allocate FPU save slots and restore register state.  Instead,
the VISEntry et al. calls should be doing that work.

This bug is about two decades old.

Reported-by: James Y Knight <jyknight@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06 19:13:25 -07:00