Current implementation of cpu_{suspend}/cpu_{resume} relies on the MPIDR
to index the array of pointers where the context is saved and restored.
The current approach works as long as the MPIDR can be considered a
linear index, so that the pointers array can simply be dereferenced by
using the MPIDR[7:0] value.
On ARM multi-cluster systems, where the MPIDR may not be a linear index,
to properly dereference the stack pointer array, a mapping function should
be applied to it so that it can be used for arrays look-ups.
This patch adds code in the cpu_{suspend}/cpu_{resume} implementation
that relies on shifting and ORing hashing method to map a MPIDR value to a
set of buckets precomputed at boot to have a collision free mapping from
MPIDR to context pointers.
The hashing algorithm must be simple, fast, and implementable with few
instructions since in the cpu_resume path the mapping is carried out with
the MMU off and the I-cache off, hence code and data are fetched from DRAM
with no-caching available. Simplicity is counterbalanced with a little
increase of memory (allocated dynamically) for stack pointers buckets, that
should be anyway fairly limited on most systems.
Memory for context pointers is allocated in a early_initcall with
size precomputed and stashed previously in kernel data structures.
Memory for context pointers is allocated through kmalloc; this
guarantees contiguous physical addresses for the allocated memory which
is fundamental to the correct functioning of the resume mechanism that
relies on the context pointer array to be a chunk of contiguous physical
memory. Virtual to physical address conversion for the context pointer
array base is carried out at boot to avoid fiddling with virt_to_phys
conversions in the cpu_resume path which is quite fragile and should be
optimized to execute as few instructions as possible.
Virtual and physical context pointer base array addresses are stashed in a
struct that is accessible from assembly using values generated through the
asm-offsets.c mechanism.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Colin Cross <ccross@android.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
On ARM SMP systems, cores are identified by their MPIDR register.
The MPIDR guidelines in the ARM ARM do not provide strict enforcement of
MPIDR layout, only recommendations that, if followed, split the MPIDR
on ARM 32 bit platforms in three affinity levels. In multi-cluster
systems like big.LITTLE, if the affinity guidelines are followed, the
MPIDR can not be considered an index anymore. This means that the
association between logical CPU in the kernel and the HW CPU identifier
becomes somewhat more complicated requiring methods like hashing to
associate a given MPIDR to a CPU logical index, in order for the look-up
to be carried out in an efficient and scalable way.
This patch provides a function in the kernel that starting from the
cpu_logical_map, implement collision-free hashing of MPIDR values by checking
all significative bits of MPIDR affinity level bitfields. The hashing
can then be carried out through bits shifting and ORing; the resulting
hash algorithm is a collision-free though not minimal hash that can be
executed with few assembly instructions. The mpidr is filtered through a
mpidr mask that is built by checking all bits that toggle in the set of
MPIDRs corresponding to possible CPUs. Bits that do not toggle do not carry
information so they do not contribute to the resulting hash.
Pseudo code:
/* check all bits that toggle, so they are required */
for (i = 1, mpidr_mask = 0; i < num_possible_cpus(); i++)
mpidr_mask |= (cpu_logical_map(i) ^ cpu_logical_map(0));
/*
* Build shifts to be applied to aff0, aff1, aff2 values to hash the mpidr
* fls() returns the last bit set in a word, 0 if none
* ffs() returns the first bit set in a word, 0 if none
*/
fs0 = mpidr_mask[7:0] ? ffs(mpidr_mask[7:0]) - 1 : 0;
fs1 = mpidr_mask[15:8] ? ffs(mpidr_mask[15:8]) - 1 : 0;
fs2 = mpidr_mask[23:16] ? ffs(mpidr_mask[23:16]) - 1 : 0;
ls0 = fls(mpidr_mask[7:0]);
ls1 = fls(mpidr_mask[15:8]);
ls2 = fls(mpidr_mask[23:16]);
bits0 = ls0 - fs0;
bits1 = ls1 - fs1;
bits2 = ls2 - fs2;
aff0_shift = fs0;
aff1_shift = 8 + fs1 - bits0;
aff2_shift = 16 + fs2 - (bits0 + bits1);
u32 hash(u32 mpidr) {
u32 l0, l1, l2;
u32 mpidr_masked = mpidr & mpidr_mask;
l0 = mpidr_masked & 0xff;
l1 = mpidr_masked & 0xff00;
l2 = mpidr_masked & 0xff0000;
return (l0 >> aff0_shift | l1 >> aff1_shift | l2 >> aff2_shift);
}
The hashing algorithm relies on the inherent properties set in the ARM ARM
recommendations for the MPIDR. Exotic configurations, where for instance the
MPIDR values at a given affinity level have large holes, can end up requiring
big hash tables since the compression of values that can be achieved through
shifting is somewhat crippled when holes are present. Kernel warns if
the number of buckets of the resulting hash table exceeds the number of
possible CPUs by a factor of 4, which is a symptom of a very sparse HW
MPIDR configuration.
The hash algorithm is quite simple and can easily be implemented in assembly
code, to be used in code paths where the kernel virtual address space is
not set-up (ie cpu_resume) and instruction and data fetches are strongly
ordered so code must be compact and must carry out few data accesses.
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Colin Cross <ccross@android.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Stephen Warren <swarren@wwwdotorg.org>
From Shawn Guo:
imx soc changes for 3.11:
* New SoCs i.MX6 Sololite and Vybrid VF610 support
* imx5 and imx6 clock fixes and additions
* Update clock driver to use of_clk_init() function
* Refactor restart routine mxc_restart() to get it work for DT boot
as well
* Clean up mxc specific ulpi access ops
* imx defconfig updates
* tag 'imx-soc-3.11' of git://git.linaro.org/people/shawnguo/linux-2.6: (29 commits)
ARM: imx_v6_v7_defconfig: Enable Vybrid VF610
ARM: imx_v6_v7_defconfig: Enable imx-wm8962 by default
ARM: clk-imx6qdl: Add clko1 configuration for imx6qdl-sabresd
ARM: imx_v6_v7_defconfig: Enable PWM and backlight options
ARM: imx: Remove mxc specific ulpi access ops
ARM: imx: add initial support for VF610
ARM: imx: add VF610 clock support
ARM: imx_v6_v7_defconfig: enable parallel display
ARM: imx: clk: No need to initialize phandle struct
ARM: imx: irq-common: Include header to avoid sparse warning
ARM: imx: Enable mx6 solo-lite support
ARM: imx6: use common of_clk_init() call to initialize clocks
ARM: imx6q: call of_clk_init() to register fixed rate clocks
ARM: imx: imx_v6_v7_defconfig: Select CONFIG_DRM_IMX_TVE
ARM: i.MX6: clk: add different DualLite MLB clock config
ARM i.MX5: Add S/PDIF clocks
ARM i.MX53: Add SATA clock
ARM: imx6q: clk: add the eim_slow clock
ARM: imx: remove MLB PLL from pllv3
ARM: imx: disable pll8_mlb in mx6q_clks
...
Conflicts:
arch/arm/Kconfig.debug (simple add/add conflict)
Includes an update to 3.10-rc6
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
From Linus Walleij:
This is a patch series that:
- Pulls the Integrator/AP PCI bridge driver into one file
- Adds full device tree support for it
- Keeps ATAG support around for the time being
* tag 'integrator-pci-for-arm-soc' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-integrator:
ARM: integrator: basic PCIv3 device tree support
ARM: integrator: move static ioremapping into PCIv3 driver
ARM: integrator: move VGA base assignment
ARM: integrator: remap PCIv3 base dynamically
ARM: integrator: move V3 register definitions into driver
ARM: integrator: move PCI base address grab to probe
ARM: integrator: grab PCI error IRQ in probe()
ARM: integrator: convert PCIv3 bridge to platform device
ARM: integrator: merge PCIv3 driver into one file
ARM: pci: create pci_common_init_dev()
Documentation/devicetree: add a small note on PCI
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Conflicts:
arch/arm/kernel/smp.c
Please pull these miscellaneous LPAE fixes I've been collecting for a while
now for 3.11. They've been tested and reviewed by quite a few people, and most
of the patches are pretty trivial. -- Will Deacon.
These changes bring both HugeTLB support and Transparent HugePage
(THP) support to ARM. Only long descriptors (LPAE) are supported
in this series.
The code has been tested on an Arndale board (Exynos 5250).
Add comments to machine_shutdown()/halt()/power_off()/restart() that
describe their purpose and/or requirements re: CPUs being active/not.
In machine_shutdown(), replace the call to smp_send_stop() with a call to
disable_nonboot_cpus(). This completely disables all but one CPU, thus
satisfying the requirement that only a single CPU be active for kexec.
Adjust Kconfig dependencies for this change.
In machine_halt()/power_off()/restart(), call smp_send_stop() directly,
rather than via machine_shutdown(); these functions don't need to
completely de-activate all CPUs using hotplug, but rather just quiesce
them.
Remove smp_kill_cpus(), and its call from smp_send_stop().
smp_kill_cpus() was indirectly calling smp_ops.cpu_kill() without calling
smp_ops.cpu_die() on the target CPUs first. At least some implementations
of smp_ops had issues with this; it caused cpu_kill() to hang on Tegra,
for example. Since smp_send_stop() is only used for shutdown, halt, and
power-off, there is no need to attempt any kind of CPU hotplug here.
Adjust Kconfig to reflect that machine_shutdown() (and hence kexec)
relies upon disable_nonboot_cpus(). However, this alone doesn't guarantee
that hotplug will work, or even that hotplug is implemented for a
particular piece of HW that a multi-platform zImage runs on. Hence, add
error-checking to machine_kexec() to determine whether it did work.
Suggested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Zhangfei Gao <zhangfei.gao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This includes the following series sent earlier to the list:
- nommu-fixes
- R7 Support
- MPU support
I've left out the ARCH_MULTIPLATFORM/!MMU stuff that Arnd and I were
discussing today until we've reached a conclusion/that's had some more
review.
This is rebased (and re-tested) on your devel-stable branch because
otherwise there were going to be conflicts with Uwe's V7M work now that
you've merged that. I've included the fix for limiting MPU to CPU_V7.
Without an MMU it is possible for userspace programs to start executing code
in places that they have no business executing. The MPU allows some level of
protection against this.
This patch protects the vectors page from access by userspace processes.
Userspace tasks that dereference a null pointer are already protected by an
svc at 0x0 that kills them. However when tasks use an offset from a null
pointer (eg a function in a null struct) they miss this carefully placed svc
and enter the exception vectors in user mode, ending up in the kernel.
This patch causes programs that do this to receive a SEGV instead of happily
entering the kernel in user-mode, and hence avoid a 'Bad Mode' panic.
As part of this change it is necessary to make sigreturn happen via the
stack when there is not an sa_restorer function. This change is invisible to
userspace, and irrelevant to code compiled using a uClibc toolchain, which
always uses an sa_restorer function.
Because we don't get to remap the vectors in !MMU kuser_helpers are not
in a defined location, and hence aren't usable. This means we don't need to
worry about keeping them accessible from PL0
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CC: Nicolas Pitre <nico@linaro.org>
CC: Catalin Marinas <catalin.marinas@arm.com>
Running an OABI_COMPAT kernel on an SMP platform can lead to fun and
games with page aging.
If one CPU issues a swi instruction immediately before another CPU
decides to mkold the page containing the swi instruction, then we will
fault attempting to load the instruction during the vector_swi handler
in order to retrieve its immediate field. Since this fault is not
currently dealt with by our exception tables, this results in a panic:
Unable to handle kernel paging request at virtual address 4020841c
pgd = c490c000
[4020841c] *pgd=84451831, *pte=bf05859d, *ppte=00000000
Internal error: Oops: 17 [#1] PREEMPT SMP ARM
Modules linked in: hid_sony(O)
CPU: 1 Tainted: G W O (3.4.0-perf-gf496dca-01162-gcbcc62b #1)
PC is at vector_swi+0x28/0x88
LR is at 0x40208420
This patch wraps all of the swi instruction loads with the USER macro
and provides a shared exception table entry which simply rewinds the
saved user PC and returns from the system call (without setting tbl, so
there's no worries with tracing or syscall restarting). Returning to
userspace will re-enter the page fault handler, from where we will
probably send SIGSEGV to the current task.
Reported-by: Wang, Yalin <yalin.wang@sonymobile.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Nothing about the sched_clock implementation in the ARM port is
specific to the architecture. Generalize the code so that other
architectures can use it by selecting GENERIC_SCHED_CLOCK.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[jstultz: Merge minor collisions with other patches in my tree]
Signed-off-by: John Stultz <john.stultz@linaro.org>
If we're suspended and sched_clock() is called we're going to
read the hardware one more time and throw away that value and
return back the cached value we saved during the suspend
callback. This is wasteful. Let's short circuit all that and
return the cached value as early as possible if we're suspended.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The needs_suspend member is unused now that we always do the
suspend/resume handling (see 6a4dae5 (ARM: 7565/1: sched: stop
sched_clock() during suspend, 2012-10-23)).
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
The MPU initialisation on the primary core is performed in two stages, one
minimal stage to ensure the CPU can boot and a second one after
sanity_check_meminfo. As the memory configuration is known by the time we
boot secondary cores only a single step is necessary, provided the values
for DRSR are passed to secondaries.
This patch implements this arrangement. The configuration generated for the
MPU regions is made available to the secondary core, which can then use the
asm MPU intialisation code to program a complete region configuration.
This is necessary for SMP configurations without an MMU, as the MPU
initialisation is the only way to ensure that memory is specified as
'shared'.
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CC: Nicolas Pitre <nico@linaro.org>
This patch adds initial support for using the MPU, which is necessary for
SMP operation on PMSAv7 processors because it is the only way to ensure
memory is shared. This is an initial patch and full SMP support is added
later in this series.
The setup of the MPU is performed in a way analagous to that for the MMU:
Very early initialisation before the C environment is brought up, followed
by a sanity check and more complete initialisation in C.
This patch provides the simplest possible memory region configuration:
MPU_PROBE_REGION: Reserved for probing MPU details, not enabled
MPU_BG_REGION: A 'background' region that specifies all memory strongly ordered
MPU_RAM_REGION: A single shared, cacheable, normal region for the valid RAM.
In this early initialisation code we simply map the whole of the address
space with the BG_REGION and (at least) the kernel with the RAM_REGION. The
MPU has region alignment constraints that require us to round past the end
of the kernel.
As region 2 has a higher priority than region 1, it overrides the strongly-
ordered behaviour for RAM only.
Subsequent patches will add more complete initialisation from the C-world
and support for bringing up secondary CPUs.
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
CC: Hyok S. Choi <hyok.choi@samsung.com>
Without an MMU we don't need to do any TLB maintenance. Until the addition
of 93dc68876b (ARM: 7684/1: errata: Workaround for Cortex-A15 erratum 798181
(TLBI/DSB operations)) building the tlb maintenance ops in smp_tlb.c worked,
though none of the contents were used.
Since that commit, however, SMP NOMMU has not been able to build. This patch
restores that ability by making the building of smp_tlb.c dependent on MMU.
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
CC: Will Deacon <will.deacon@arm.com>
The ARM CPU suspend code can be selected even for a !CONFIG_MMU
configuration. The resulting kernel will not compile and, even if it did,
would access undefined co-processor registers when executing.
This patch fixes the v6 and v7 CPU suspend code for the nommu case.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Tested-by: Jonathan Austin <jonathan.austin@arm.com>
CC: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> (commit_signer:1/3=33%)
CC: Santosh Shilimkar <santosh.shilimkar@ti.com> (commit_signer:1/3=33%)
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
nommu systems do not require any page tables, so don't try to initialise
them when bringing up secondary cores.
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch adds a secondary_startup entry point to head-nommu.S so that
we can boot secondary CPUs on an SMP nommu configuration.
Signed-off-by: Will Deacon <will.deacon@arm.com>
CC: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
CC: Nicolas Pitre <nico@linaro.org>
When booting the kernel, a bootloader could have left the virtual
timer ticking away, potentially generating interrupts. This could
be troublesome if the user of the virtual timer is not careful
when enabling the interrupt.
In order to avoid any surprise, stop the virtual timer from
interrupting us when booted in HYP mode, as we'll use the physical
timer in this case.
Reported-by: Giridhar Maruthy <giridhar.m@samsung.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Dave Martin <dave.martin@linaro.org>
The cpu_topology symbol is required by any driver using the topology
interfaces, which leads to a couple of build errors:
ERROR: "cpu_topology" [drivers/net/ethernet/sfc/sfc.ko] undefined!
ERROR: "cpu_topology" [drivers/cpufreq/arm_big_little.ko] undefined!
ERROR: "cpu_topology" [drivers/block/mtip32xx/mtip32xx.ko] undefined!
The obvious solution is to export this symbol.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
When working with device tree support for PCI on ARM you run
into a problem when mapping IRQs from the device tree irqmaps:
doing this the code in drivers/of/of_pci_irq.c will try to
find the OF node on the root bridge and this fails, because
bus->dev.of_node is NULL, and that in turn boils down to
the fact that pci_set_bus_of_node() has called
pcibios_get_phb_of_node() from drivers/pci/of.c to obtain
the OF node of the bridge or its parent and none is set
and thus NULL is returned.
Fix this by adding an additional parent argument API for
registering PCI bridges on the ARM architecture called
pci_common_init_dev(), and pass along this parent to
pci_scan_root_bus() called from pcibios_init_hw() in
bios32.c and voila: the IRQ mappings start working:
the OF node can be retrieved from the parent.
Create the old pci_common_init() as a wrapper around
the new call.
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmitt <benh@kernel.crashing.org>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Pulling in base dependencies from rmk's devel-stable branch needed by the
CCI patches for vexpress.
Signed-off-by: Olof Johansson <olof@lixom.net>
* depends/rmk-devel-stable:
ARM: Enable selection of SMP operations at boot time
arm: introduce psci_smp_ops
ARM: ARMv7-M: implement read_cpuid_ext
ARM: ARMv7-M: Allow the building of new kernel port
ARM: ARMv7-M: Add support for exception handling
ARM: Add base support for ARMv7-M
CPUs implementing LPAE have atomic ldrd/strd instructions, meaning that
userspace software can avoid having to use the exclusive variants of
these instructions if they wish.
This patch advertises the atomicity of these instructions via the
hwcaps, so userspace can detect this CPU feature.
Reported-by: Vladimir Danushevsky <vladimir.danushevsky@oracle.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch redefines the early boot time use of the R4 register to steal a few
low order bits (ARCH_PGD_SHIFT bits) on LPAE systems. This allows for up to
38-bit physical addresses.
Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Subash Patel <subash.rp@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Pull ARM fixes from Russell King:
"Just three this time, all really quite small"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7729/1: vfp: ensure VFP_arch is non-zero when VFP is not supported
ARM: 7727/1: remove the .vm_mm value from gate_vma
ARM: 7723/1: crypto: sha1-armv4-large.S: fix SP handling
If one reads /proc/$PID/smaps, the mmap_sem belonging to the
address space of the task being examined is locked for reading.
All the pages of the vmas belonging to the task's address space
are then walked with this lock held.
If a gate_vma is present in the architecture, it too is examined
by the fs/proc/task_mmu.c code. As gate_vma doesn't belong to the
address space of the task though, its pages are not walked.
A recent cleanup (commit f6604efe) of the gate_vma initialisation
code set the vm_mm value to &init_mm. Unfortunately a non-NULL
vm_mm value in the gate_vma will cause the task_mmu code to attempt
to walk the pages of the gate_vma (with no mmap-sem lock held). If
one enables Transparent Huge Page support and vm debugging, this
will then cause OOPses as pmd_trans_huge_lock is called without
mmap_sem being locked.
This patch removes the .vm_mm value from gate_vma, restoring the
original behaviour of the task_mmu code.
Signed-off-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull psci_smp_ops support from Stefano Stabellini:
It contains the generic PSCI patch and the smp_init patch that we
discussed so much about. I think it would be helpful for other
people if you could create a stable branch with these patches so
that SoC devs can base their work on it.
Pull ARM-v7M support from Uwe Kleine-König:
"All but the last patch were in next since next-20130418 without issues.
The last patch fixes a problem in combination with
8164f7a (ARM: 7680/1: Detect support for SDIV/UDIV from ISAR0 register)
which triggers a WARN_ON without an implemented read_cpuid_ext.
The branch merges fine into v3.10-rc1 and I'd be happy if you pulled it
for 3.11-rc1. The only missing piece to be able to run a Cortex-M3 is
the irqchip driver that will go in via Thomas Gleixner and platform
specific stuff."
Before f7b861b7a6 ("arm: Use generic idle loop") ARM would kill the
CPU within the rcu idle section. Now that the rcu_idle_enter()/exit()
pair have been pushed lower down in the idle loop this is no longer true
and so using RCU_NONIDLE here is no longer necessary and also harmful
because RCU is not actually idle at this point.
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new 'smp_init' hook to machine_desc so platforms can specify a
function to be used to setup smp ops instead of having a statically
defined value. The hook must return true when smp_ops are initialized.
If false the static mdesc->smp_ops will be used by default.
Add the definition of "bool" by including the linux/types.h file to
asm/mach/arch.h and make it self-contained.
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Rename virt_smp_ops to psci_smp_ops and move them to arch/arm/kernel/psci_smp.c.
Remove mach-virt/platsmp.c, now unused.
Compile psci_smp if CONFIG_ARM_PSCI and CONFIG_SMP.
Add a cpu_die smp_op based on psci_ops.cpu_off.
Initialize PSCI before setting smp_ops in setup_arch.
If PSCI is available on the platform, prefer psci_smp_ops over the
platform smp_ops.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Will Deacon <will.deacon@arm.com>
CC: arnd@arndb.de
CC: marc.zyngier@arm.com
CC: linux@arm.linux.org.uk
CC: nico@linaro.org
CC: rob.herring@calxeda.com
Commit 14318efb(ARM: 7587/1: implement optimized percpu variable access)
introduces arm's __my_cpu_offset to optimize percpu vaiable access,
which really works well on hackbench, but will cause __my_cpu_offset
to return garbage value before it is initialized in cpu_init() called
by setup_arch, so accessing percpu variable before setup_arch may cause
kernel hang. But generic __my_cpu_offset always returns zero before
percpu area is brought up, and won't hang kernel.
So the patch tries to clear __my_cpu_offset on boot CPU early
to avoid boot hang.
At least now percpu variable is accessed by lockdep before
setup_arch(), and enabling CONFIG_LOCK_STAT or CONFIG_DEBUG_LOCKDEP
can trigger kernel hang.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* late/fixes:
ARM: OMAP2+: Fix unmet direct dependencies for SERIAL_OMAP
ARM: ux500: always select ABX500_CORE
ARM: SIRF: select SMP_ON_UP only on SMP builds
ARM: SPEAr: conditionalize l2x0 support
ARM: imx: build CPU suspend code only when needed
ARM: OMAP: build SMP code only for OMAP4/5
ARM: tegra: Tegra114 needs CPU_FREQ_TABLE
ARM: default machine descriptor for multiplatform
Signed-off-by: Olof Johansson <olof@lixom.net>
Pull ARM SoC late cleanups from Arnd Bergmann:
"These are cleanups and smaller changes that either depend on earlier
feature branches or came in late during the development cycle. We
normally try to get all cleanups early, so these are the exceptions:
- A follow-up on the clocksource reworks, hopefully the last time we
need to merge clocksource subsystem changes through arm-soc.
A first set of patches was part of the original 3.10 arm-soc
cleanup series because of interdependencies with timer drivers now
moved out of arch/arm.
- Migrating the SPEAr13xx platform away from using auxdata for DMA
channel descriptions towards using information in device tree,
based on the earlier SPEAr multiplatform series
- A few follow-ups on the Atmel SAMA5 support and other changes for
Atmel at91 based on the larger at91 reworks.
- Moving the armada irqchip implementation to drivers/irqchip
- Several OMAP cleanups following up on the larger series already
merged in 3.10."
* tag 'cleanup-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (50 commits)
ARM: OMAP4: change the device names in usb_bind_phy
ARM: OMAP2+: Fix mismerge for timer.c between ff931c82 and da4a686a
ARM: SPEAr: conditionalize SMP code
ARM: arch_timer: Silence debug preempt warnings
ARM: OMAP: remove unused variable
serial: amba-pl011: fix !CONFIG_DMA_ENGINE case
ata: arasan: remove the need for platform_data
ARM: at91/sama5d34ek.dts: remove not needed compatibility string
ARM: at91: dts: add MCI DMA support
ARM: at91: dts: add i2c dma support
ARM: at91: dts: set #dma-cells to the correct value
ARM: at91: suspend both memory controllers on at91sam9263
irqchip: armada-370-xp: slightly cleanup irq controller driver
irqchip: armada-370-xp: move IRQ handler to avoid forward declaration
irqchip: move IRQ driver for Armada 370/XP
ARM: mvebu: move L2 cache initialization in init_early()
devtree: add binding documentation for sp804
ARM: integrator-cp: convert use CLKSRC_OF for timer init
ARM: versatile: use OF init for sp804 timer
ARM: versatile: add versatile dtbs to dtbs target
...
There is no reason to keep the clksrc cleanups separate from the
other cleanups, and this resolves some merge conflicts.
Conflicts:
arch/arm/mach-spear/spear13xx.c
drivers/irqchip/Makefile
Pull kvm updates from Gleb Natapov:
"Highlights of the updates are:
general:
- new emulated device API
- legacy device assignment is now optional
- irqfd interface is more generic and can be shared between arches
x86:
- VMCS shadow support and other nested VMX improvements
- APIC virtualization and Posted Interrupt hardware support
- Optimize mmio spte zapping
ppc:
- BookE: in-kernel MPIC emulation with irqfd support
- Book3S: in-kernel XICS emulation (incomplete)
- Book3S: HV: migration fixes
- BookE: more debug support preparation
- BookE: e6500 support
ARM:
- reworking of Hyp idmaps
s390:
- ioeventfd for virtio-ccw
And many other bug fixes, cleanups and improvements"
* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
kvm: Add compat_ioctl for device control API
KVM: x86: Account for failing enable_irq_window for NMI window request
KVM: PPC: Book3S: Add API for in-kernel XICS emulation
kvm/ppc/mpic: fix missing unlock in set_base_addr()
kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
kvm/ppc/mpic: remove users
kvm/ppc/mpic: fix mmio region lists when multiple guests used
kvm/ppc/mpic: remove default routes from documentation
kvm: KVM_CAP_IOMMU only available with device assignment
ARM: KVM: iterate over all CPUs for CPU compatibility check
KVM: ARM: Fix spelling in error message
ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
KVM: ARM: Fix API documentation for ONE_REG encoding
ARM: KVM: promote vfp_host pointer to generic host cpu context
ARM: KVM: add architecture specific hook for capabilities
ARM: KVM: perform HYP initilization for hotplugged CPUs
ARM: KVM: switch to a dual-step HYP init code
ARM: KVM: rework HYP page table freeing
ARM: KVM: enforce maximum size for identity mapped code
ARM: KVM: move to a KVM provided HYP idmap
...
Pull ARM updates from Russell King:
"The major items included in here are:
- MCPM, multi-cluster power management, part of the infrastructure
required for ARMs big.LITTLE support.
- A rework of the ARM KVM code to allow re-use by ARM64.
- Error handling cleanups of the IS_ERR_OR_NULL() madness and fixes
of that stuff for arch/arm
- Preparatory patches for Cortex-M3 support from Uwe Kleine-König.
There is also a set of three patches in here from Hugh/Catalin to
address freeing of inappropriate page tables on LPAE. You already
have these from akpm, but they were already part of my tree at the
time he sent them, so unfortunately they'll end up with duplicate
commits"
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits)
ARM: EXYNOS: remove unnecessary use of IS_ERR_VALUE()
ARM: IMX: remove unnecessary use of IS_ERR_VALUE()
ARM: OMAP: use consistent error checking
ARM: cleanup: OMAP hwmod error checking
ARM: 7709/1: mcpm: Add explicit AFLAGS to support v6/v7 multiplatform kernels
ARM: 7700/2: Make cpu_init() notrace
ARM: 7702/1: Set the page table freeing ceiling to TASK_SIZE
ARM: 7701/1: mm: Allow arch code to control the user page table ceiling
ARM: 7703/1: Disable preemption in broadcast_tlb*_a15_erratum()
ARM: mcpm: provide an interface to set the SMP ops at run time
ARM: mcpm: generic SMP secondary bringup and hotplug support
ARM: mcpm_head.S: vlock-based first man election
ARM: mcpm: Add baremetal voting mutexes
ARM: mcpm: introduce helpers for platform coherency exit/setup
ARM: mcpm: introduce the CPU/cluster power API
ARM: multi-cluster PM: secondary kernel entry code
ARM: cacheflush: add synchronization helpers for mixed cache state accesses
ARM: cpu hotplug: remove majority of cache flushing from platforms
ARM: smp: flush L1 cache in cpu_die()
ARM: tegra: remove tegra specific cpu_disable()
...
Pull ARM SoC cleanup from Olof Johansson:
"Here is a collection of cleanup patches. Among the pieces that stand
out are:
- The deletion of h720x platforms
- Split of at91 non-dt platforms to their own Kconfig file to keep
them separate
- General cleanups and refactoring of i.MX and MXS platforms
- Some restructuring of clock tables for OMAP
- Convertion of PMC driver for Tegra to dt-only
- Some renames of sunxi -> sun4i (Allwinner A10)
- ... plus a bunch of other stuff that I haven't mentioned"
* tag 'cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (119 commits)
ARM: i.MX: remove unused ARCH_* configs
ARM i.MX53: remove platform ahci support
ARM: sunxi: Rework the restart code
irqchip: sunxi: Rename sunxi to sun4i
irqchip: sunxi: Make use of the IRQCHIP_DECLARE macro
clocksource: sunxi: Rename sunxi to sun4i
clocksource: sunxi: make use of CLKSRC_OF
clocksource: sunxi: Cleanup the timer code
ARM: at91: remove trailing semicolon from macros
ARM: at91/setup: fix trivial typos
ARM: EXYNOS: remove "config EXYNOS_DEV_DRM"
ARM: EXYNOS: change the name of USB ohci header
ARM: SAMSUNG: Remove unnecessary code for dma
ARM: S3C24XX: Remove unused GPIO drive strength register definitions
ARM: OMAP4+: PM: Restore CPU power state to ON with clockdomain force wakeup method
ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2412
ARM: S3C24XX: Removed unneeded dependency on CPU_S3C2410
ARM: S3C24XX: Removed unneeded dependency on ARCH_S3C24XX for boards
ARM: SAMSUNG: Fix typo "CONFIG_SAMSUNG_DEV_RTC"
ARM: S5P64X0: Fix typo "CONFIG_S5P64X0_SETUP_SDHCI"
...
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Currently help message of /proc/sysrq-trigger highlights its
upper-case characters, like below:
SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E)
memory-full-oom-kill(F) kill-all-tasks(I) ...
this would confuse user trigger sysrq by upper-case character, which is
inconsistent with the real lower-case character registed key.
This inconsistent help message will also lead more confused when
26 upper-case letters put into use in future.
This patch fix arm etm sysrq key: "etm-buffer-dump(v)"
(This patch also add "-" to separate each sysrq key help word,
instead of spaces)
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms. This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.
show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.
* Archs which didn't print debug info now do.
alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
um, xtensa
* Already prints debug info. Replaced with show_regs_print_info().
The printed information is superset of what used to be there.
arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86
* s390 is special in that it used to print arch-specific information
along with generic debug info. Heiko and Martin think that the
arch-specific extra isn't worth keeping s390 specfic implementation.
Converted to use the generic version.
Note that now all archs print the debug info before actual register
dumps.
An example BUG() dump follows.
kernel BUG at /work/os/work/kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[<ffffffff81000312>] do_one_initcall+0x122/0x170
[<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
[<ffffffff81c47760>] ? rest_init+0x140/0x140
[<ffffffff81c4776e>] kernel_init+0xe/0xf0
[<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
[<ffffffff81c47760>] ? rest_init+0x140/0x140
...
v2: Typo fix in x86-32.
v3: CPU number dropped from show_regs_print_info() as
dump_stack_print_info() has been updated to print it. s390
specific implementation dropped as requested by s390 maintainers.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
