linux.git/arch/arm, branch v4.3-rc2

Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

2015-09-20T04:05:02+00:00

Pull ARM fixes from Russell King:
 "Three fixes and a resulting cleanup for -rc2:

   - Andre Przywara reported that he was seeing a warning with the new
     cast inside DMA_ERROR_CODE's definition, and fixed the incorrect
     use.

   - Doug Anderson noticed that kgdb causes a "scheduling while atomic"
     bug.

   - OMAP5 folk noticed that their Thumb-2 compiled X servers crashed
     when enabling support to cover ARMv6 CPUs due to a kernel bug
     leaking some conditional context into the signal handler"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8425/1: kgdb: Don't try to stop the machine when setting breakpoints
  ARM: 8437/1: dma-mapping: fix build warning with new DMA_ERROR_CODE definition
  ARM: get rid of needless #if in signal handling code
  ARM: fix Thumb2 signal handling when ARMv6 is enabled

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2015-09-18T16:23:08+00:00

Pull KVM fixes from Paolo Bonzini:
 "Mostly stable material, a lot of ARM fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (22 commits)
  sched: access local runqueue directly in single_task_running
  arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS'
  arm64: KVM: Remove all traces of the ThumbEE registers
  arm: KVM: Disable virtual timer even if the guest is not using it
  arm64: KVM: Disable virtual timer even if the guest is not using it
  arm/arm64: KVM: vgic: Check for !irqchip_in_kernel() when mapping resources
  KVM: s390: Replace incorrect atomic_or with atomic_andnot
  arm: KVM: Fix incorrect device to IPA mapping
  arm64: KVM: Fix user access for debug registers
  KVM: vmx: fix VPID is 0000H in non-root operation
  KVM: add halt_attempted_poll to VCPU stats
  kvm: fix zero length mmio searching
  kvm: fix double free for fast mmio eventfd
  kvm: factor out core eventfd assign/deassign logic
  kvm: don't try to register to KVM_FAST_MMIO_BUS for non mmio eventfd
  KVM: make the declaration of functions within 80 characters
  KVM: arm64: add workaround for Cortex-A57 erratum #852523
  KVM: fix polling for guest halt continued even if disable it
  arm/arm64: KVM: Fix PSCI affinity info return value for non valid cores
  arm64: KVM: set {v,}TCR_EL2 RES1 bits
  ...

Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2015-09-18T15:11:42+00:00

Pull irq updates from Thomas Gleixner:
 "This is a rather large update post rc1 due to the final steps of
  cleanups and API changes which had to wait for the preparatory patches
  to hit your tree.

   - Regression fixes for ARM GIC irqchips

   - Regression fixes and lockdep anotations for renesas irq chips

   - The leftovers of the cleanup and preparatory patches which have
     been ignored by maintainers

   - Final conversions of the newly merged users of obsolete APIs

   - Final removal of obsolete APIs

   - Final removal of ARM artifacts which had been introduced during the
     conversion of ARM to the generic interrupt code.

   - Final split of the irq_data into chip specific and common data to
     reflect the needs of hierarchical irq domains.

   - Treewide removal of the first argument of interrupt flow handlers,
     i.e. the irq number, which is not used by the majority of handlers
     and simple to retrieve from the other argument the irq descriptor.

   - A few comment updates and build warning fixes"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  arm64: Remove ununsed set_irq_flags
  ARM: Remove ununsed set_irq_flags
  sh: Kill off set_irq_flags usage
  irqchip: Kill off set_irq_flags usage
  gpu/drm: Kill off set_irq_flags usage
  genirq: Remove irq argument from irq flow handlers
  genirq: Move field 'msi_desc' from irq_data into irq_common_data
  genirq: Move field 'affinity' from irq_data into irq_common_data
  genirq: Move field 'handler_data' from irq_data into irq_common_data
  genirq: Move field 'node' from irq_data into irq_common_data
  irqchip/gic-v3: Use IRQD_FORWARDED_TO_VCPU flag
  irqchip/gic: Use IRQD_FORWARDED_TO_VCPU flag
  genirq: Provide IRQD_FORWARDED_TO_VCPU status flag
  genirq: Simplify irq_data_to_desc()
  genirq: Remove __irq_set_handler_locked()
  pinctrl/pistachio: Use irq_set_handler_locked
  gpio: vf610: Use irq_set_handler_locked
  powerpc/mpc8xx: Use irq_set_handler_locked()
  powerpc/ipic: Use irq_set_handler_locked()
  powerpc/cpm2: Use irq_set_handler_locked()
  ...

Merge tag 'kvm-arm-for-4.3-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

2015-09-17T14:51:59+00:00

Second set of KVM/ARM changes for 4.3-rc2

- Workaround for a Cortex-A57 erratum
- Bug fix for the debugging infrastructure
- Fix for 32bit guests with more than 4GB of address space
  on a 32bit host
- A number of fixes for the (unusual) case when we don't use
  the in-kernel GIC emulation
- Removal of ThumbEE handling on arm64, since these have been
  dropped from the architecture before anyone actually ever
  built a CPU
- Remove the KVM_ARM_MAX_VCPUS limitation which has become
  fairly pointless

arm/arm64: KVM: Remove 'config KVM_ARM_MAX_VCPUS'

2015-09-17T12:13:27+00:00

This patch removes config option of KVM_ARM_MAX_VCPUS,
and like other ARCHs, just choose the maximum allowed
value from hardware, and follows the reasons:

1) from distribution view, the option has to be
defined as the max allowed value because it need to
meet all kinds of virtulization applications and
need to support most of SoCs;

2) using a bigger value doesn't introduce extra memory
consumption, and the help text in Kconfig isn't accurate
because kvm_vpu structure isn't allocated until request
of creating VCPU is sent from QEMU;

3) the main effect is that the field of vcpus[] in 'struct kvm'
becomes a bit bigger(sizeof(void *) per vcpu) and need more cache
lines to hold the structure, but 'struct kvm' is one generic struct,
and it has worked well on other ARCHs already in this way. Also,
the world switch frequecy is often low, for example, it is ~2000
when running kernel building load in VM from APM xgene KVM host,
so the effect is very small, and the difference can't be observed
in my test at all.

Cc: Dann Frazier 
Signed-off-by: Ming Lei 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier

arm: KVM: Disable virtual timer even if the guest is not using it

2015-09-17T12:11:48+00:00

When running a guest with the architected timer disabled (with QEMU and
the kernel_irqchip=off option, for example), it is important to make
sure the timer gets turned off. Otherwise, the guest may try to
enable it anyway, leading to a screaming HW interrupt.

The fix is to unconditionally turn off the virtual timer on guest
exit.

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier

ARM: 8425/1: kgdb: Don't try to stop the machine when setting breakpoints

2015-09-16T22:58:46+00:00

In (23a4e40 arm: kgdb: Handle read-only text / modules) we moved to
using patch_text() to set breakpoints so that we could handle the case
when we had CONFIG_DEBUG_RODATA.  That patch used patch_text().
Unfortunately, patch_text() assumes that we're not in atomic context
when it runs since it needs to grab a mutex and also wait for other
CPUs to stop (which it does with a completion).

This would result in a stack crawl if you had
CONFIG_DEBUG_ATOMIC_SLEEP and tried to set a breakpoint in kgdb.  The
crawl looked something like:

 BUG: scheduling while atomic: swapper/0/0/0x00010007
 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-rc7-00133-geb63b34 #1073
 Hardware name: Rockchip (Device Tree)
  (unwind_backtrace) from [] (show_stack+0x20/0x24)
  (show_stack) from [] (dump_stack+0x84/0xb8)
  (dump_stack) from [] (__schedule_bug+0x54/0x6c)
  (__schedule_bug) from [] (__schedule+0x80/0x668)
  (__schedule) from [] (schedule+0xb8/0xd4)
  (schedule) from [] (schedule_timeout+0x2c/0x234)
  (schedule_timeout) from [] (wait_for_common+0xf4/0x188)
  (wait_for_common) from [] (wait_for_completion+0x20/0x24)
  (wait_for_completion) from [] (__stop_cpus+0x58/0x70)
  (__stop_cpus) from [] (stop_cpus+0x3c/0x54)
  (stop_cpus) from [] (__stop_machine+0xcc/0xe8)
  (__stop_machine) from [] (stop_machine+0x34/0x44)
  (stop_machine) from [] (patch_text+0x28/0x34)
  (patch_text) from [] (kgdb_arch_set_breakpoint+0x40/0x4c)
  (kgdb_arch_set_breakpoint) from [] (kgdb_validate_break_address+0x2c/0x60)
  (kgdb_validate_break_address) from [] (dbg_set_sw_break+0x1c/0xdc)
  (dbg_set_sw_break) from [] (gdb_serial_stub+0x9c4/0xba4)
  (gdb_serial_stub) from [] (kgdb_cpu_enter+0x1f8/0x60c)
  (kgdb_cpu_enter) from [] (kgdb_handle_exception+0x19c/0x1d0)
  (kgdb_handle_exception) from [] (kgdb_compiled_brk_fn+0x30/0x3c)
  (kgdb_compiled_brk_fn) from [] (do_undefinstr+0x1a4/0x20c)
  (do_undefinstr) from [] (__und_svc_finish+0x0/0x34)

It turns out that when we're in kgdb all the CPUs are stopped anyway
so there's no reason we should be calling patch_text().  We can
instead directly call __patch_text() which assumes that CPUs have
already been stopped.

Fixes: 23a4e4050ba9 ("arm: kgdb: Handle read-only text / modules")
Reported-by: Aapo Vienamo 
Signed-off-by: Douglas Anderson 
Reviewed-by: Stephen Boyd 
Acked-by: Kees Cook 
Signed-off-by: Russell King

ARM: 8437/1: dma-mapping: fix build warning with new DMA_ERROR_CODE definition

2015-09-16T22:58:46+00:00

Commit 96231b2686b5: ("ARM: 8419/1: dma-mapping: harmonize definition
of DMA_ERROR_CODE") changed the definition of DMA_ERROR_CODE to use
dma_addr_t, which makes the compiler barf on assigning this to an
"int" variable on ARM with LPAE enabled:
*************
In file included from /src/linux/include/linux/dma-mapping.h:86:0,
                 from /src/linux/arch/arm/mm/dma-mapping.c:21:
/src/linux/arch/arm/mm/dma-mapping.c: In function '__iommu_create_mapping':
/src/linux/arch/arm/include/asm/dma-mapping.h:16:24: warning:
overflow in implicit constant conversion [-Woverflow]
 #define DMA_ERROR_CODE (~(dma_addr_t)0x0)
                        ^
/src/linux/arch/arm/mm/dma-mapping.c:1252:15: note: in expansion of
macro DMA_ERROR_CODE'
  int i, ret = DMA_ERROR_CODE;
               ^
*************

Remove the actually unneeded initialization of "ret" in
__iommu_create_mapping() and move the variable declaration inside the
for-loop to make the scope of this variable more clear.

Signed-off-by: Andre Przywara 
Signed-off-by: Russell King

ARM: get rid of needless #if in signal handling code

2015-09-16T22:58:46+00:00

Remove the #if statement which caused trouble for kernels that support
both ARMv6 and ARMv7.  Older architectures do not implement these bits,
so it should be safe to always clear them.

Signed-off-by: Russell King

arm/arm64: KVM: vgic: Check for !irqchip_in_kernel() when mapping resources

2015-09-16T17:35:28+00:00

Until b26e5fdac43c ("arm/arm64: KVM: introduce per-VM ops"),
kvm_vgic_map_resources() used to include a check on irqchip_in_kernel(),
and vgic_v2_map_resources() still has it.

But now vm_ops are not initialized until we call kvm_vgic_create().
Therefore kvm_vgic_map_resources() can being called without a VGIC,
and we die because vm_ops.map_resources is NULL.

Fixing this restores QEMU's kernel-irqchip=off option to a working state,
allowing to use GIC emulation in userspace.

Fixes: b26e5fdac43c ("arm/arm64: KVM: introduce per-VM ops")
Cc: stable@vger.kernel.org
Signed-off-by: Pavel Fedin 
[maz: reworked commit message]
Signed-off-by: Marc Zyngier