The used_vsr flag is set if process has used VSX registers, not Altivec
registers. But the comment says otherwise, correct the comment.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull x86 protection key support from Ingo Molnar:
"This tree adds support for a new memory protection hardware feature
that is available in upcoming Intel CPUs: 'protection keys' (pkeys).
There's a background article at LWN.net:
https://lwn.net/Articles/643797/
The gist is that protection keys allow the encoding of
user-controllable permission masks in the pte. So instead of having a
fixed protection mask in the pte (which needs a system call to change
and works on a per page basis), the user can map a (handful of)
protection mask variants and can change the masks runtime relatively
cheaply, without having to change every single page in the affected
virtual memory range.
This allows the dynamic switching of the protection bits of large
amounts of virtual memory, via user-space instructions. It also
allows more precise control of MMU permission bits: for example the
executable bit is separate from the read bit (see more about that
below).
This tree adds the MM infrastructure and low level x86 glue needed for
that, plus it adds a high level API to make use of protection keys -
if a user-space application calls:
mmap(..., PROT_EXEC);
or
mprotect(ptr, sz, PROT_EXEC);
(note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
this special case, and will set a special protection key on this
memory range. It also sets the appropriate bits in the Protection
Keys User Rights (PKRU) register so that the memory becomes unreadable
and unwritable.
So using protection keys the kernel is able to implement 'true'
PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
PROT_READ as well. Unreadable executable mappings have security
advantages: they cannot be read via information leaks to figure out
ASLR details, nor can they be scanned for ROP gadgets - and they
cannot be used by exploits for data purposes either.
We know about no user-space code that relies on pure PROT_EXEC
mappings today, but binary loaders could start making use of this new
feature to map binaries and libraries in a more secure fashion.
There is other pending pkeys work that offers more high level system
call APIs to manage protection keys - but those are not part of this
pull request.
Right now there's a Kconfig that controls this feature
(CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
(like most x86 CPU feature enablement code that has no runtime
overhead), but it's not user-configurable at the moment. If there's
any serious problem with this then we can make it configurable and/or
flip the default"
* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
mm/core, x86/mm/pkeys: Add execute-only protection keys support
x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
x86/mm/pkeys: Allow kernel to modify user pkey rights register
x86/fpu: Allow setting of XSAVE state
x86/mm: Factor out LDT init from context init
mm/core, x86/mm/pkeys: Add arch_validate_pkey()
mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
x86/mm/pkeys: Add Kconfig prompt to existing config option
x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
x86/mm/pkeys: Dump PKRU with other kernel registers
mm/core, x86/mm/pkeys: Differentiate instruction fetches
x86/mm/pkeys: Optimize fault handling in access_error()
mm/core: Do not enforce PKEY permissions on remote mm access
um, pkeys: Add UML arch_*_access_permitted() methods
mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
x86/mm/gup: Simplify get_user_pages() PTE bit handling
...
Highlights:
- Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras
- Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V
- Add POWER9 cputable entry from Michael Neuling
- FPU/Altivec/VSX save/restore optimisations from Cyril Bur
- Add support for new ftrace ABI on ppc64le from Torsten Duwe
Various cleanups & minor fixes from:
- Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril
Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey,
Sukadev Bhattiprolu, Suraj Jitindar Singh.
General:
- atomics: Allow architectures to define their own __atomic_op_* helpers from
Boqun Feng
- Implement atomic{, 64}_*_return_* variants and acquire/release/relaxed
variants for (cmp)xchg from Boqun Feng
- Add powernv_defconfig from Jeremy Kerr
- Fix BUG_ON() reporting in real mode from Balbir Singh
- Add xmon command to dump OPAL msglog from Andrew Donnellan
- Add xmon command to dump process/task similar to ps(1) from Douglas Miller
- Clean up memory hotplug failure paths from David Gibson
pci/eeh:
- Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei
Yang.
- EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
- PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
- PCI: Add pcibios_bus_add_device() weak function from Wei Yang
- MAINTAINERS: Update EEH details and maintainership from Russell Currey
cxl:
- Support added to the CXL driver for running on both bare-metal and
hypervisor systems, from Christophe Lombard and Frederic Barrat.
- Ignore probes for virtual afu pci devices from Vaibhav Jain
perf:
- Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu
- hv-24x7: Fix usage with chip events, display change in counter values,
display domain indices in sysfs, eliminate domain suffix in event names,
from Sukadev Bhattiprolu
Freescale:
- Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum
optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and
other dt bits, and minor fixes/cleanup."
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Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"This was delayed a day or two by some build-breakage on old toolchains
which we've now fixed.
There's two PCI commits both acked by Bjorn.
There's one commit to mm/hugepage.c which is (co)authored by Kirill.
Highlights:
- Restructure Linux PTE on Book3S/64 to Radix format from Paul
Mackerras
- Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh
Kumar K.V
- Add POWER9 cputable entry from Michael Neuling
- FPU/Altivec/VSX save/restore optimisations from Cyril Bur
- Add support for new ftrace ABI on ppc64le from Torsten Duwe
Various cleanups & minor fixes from:
- Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy,
Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell
Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh.
General:
- atomics: Allow architectures to define their own __atomic_op_*
helpers from Boqun Feng
- Implement atomic{, 64}_*_return_* variants and acquire/release/
relaxed variants for (cmp)xchg from Boqun Feng
- Add powernv_defconfig from Jeremy Kerr
- Fix BUG_ON() reporting in real mode from Balbir Singh
- Add xmon command to dump OPAL msglog from Andrew Donnellan
- Add xmon command to dump process/task similar to ps(1) from Douglas
Miller
- Clean up memory hotplug failure paths from David Gibson
pci/eeh:
- Redesign SR-IOV on PowerNV to give absolute isolation between VFs
from Wei Yang.
- EEH Support for SRIOV VFs from Wei Yang and Gavin Shan.
- PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang
- PCI: Add pcibios_bus_add_device() weak function from Wei Yang
- MAINTAINERS: Update EEH details and maintainership from Russell
Currey
cxl:
- Support added to the CXL driver for running on both bare-metal and
hypervisor systems, from Christophe Lombard and Frederic Barrat.
- Ignore probes for virtual afu pci devices from Vaibhav Jain
perf:
- Export Power8 generic and cache events to sysfs from Sukadev
Bhattiprolu
- hv-24x7: Fix usage with chip events, display change in counter
values, display domain indices in sysfs, eliminate domain suffix in
event names, from Sukadev Bhattiprolu
Freescale:
- Updates from Scott: "Highlights include 8xx optimizations, 32-bit
checksum optimizations, 86xx consolidation, e5500/e6500 cpu
hotplug, more fman and other dt bits, and minor fixes/cleanup"
* tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits)
powerpc: Fix unrecoverable SLB miss during restore_math()
powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers
powerpc/rcpm: Fix build break when SMP=n
powerpc/book3e-64: Use hardcoded mttmr opcode
powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible
powerpc/T104xRDB: add tdm riser card node to device tree
powerpc32: PAGE_EXEC required for inittext
powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree
powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)
powerpc/86xx: Introduce and use common dtsi
powerpc/86xx: Update device tree
powerpc/86xx: Move dts files to fsl directory
powerpc/86xx: Switch to kconfig fragments approach
powerpc/86xx: Update defconfigs
powerpc/86xx: Consolidate common platform code
powerpc32: Remove one insn in mulhdu
powerpc32: small optimisation in flush_icache_range()
powerpc: Simplify test in __dma_sync()
powerpc32: move xxxxx_dcache_range() functions inline
powerpc32: Remove clear_pages() and define clear_page() inline
...
Pull networking updates from David Miller:
"Highlights:
1) Support more Realtek wireless chips, from Jes Sorenson.
2) New BPF types for per-cpu hash and arrap maps, from Alexei
Starovoitov.
3) Make several TCP sysctls per-namespace, from Nikolay Borisov.
4) Allow the use of SO_REUSEPORT in order to do per-thread processing
of incoming TCP/UDP connections. The muxing can be done using a
BPF program which hashes the incoming packet. From Craig Gallek.
5) Add a multiplexer for TCP streams, to provide a messaged based
interface. BPF programs can be used to determine the message
boundaries. From Tom Herbert.
6) Add 802.1AE MACSEC support, from Sabrina Dubroca.
7) Avoid factorial complexity when taking down an inetdev interface
with lots of configured addresses. We were doing things like
traversing the entire address less for each address removed, and
flushing the entire netfilter conntrack table for every address as
well.
8) Add and use SKB bulk free infrastructure, from Jesper Brouer.
9) Allow offloading u32 classifiers to hardware, and implement for
ixgbe, from John Fastabend.
10) Allow configuring IRQ coalescing parameters on a per-queue basis,
from Kan Liang.
11) Extend ethtool so that larger link mode masks can be supported.
From David Decotigny.
12) Introduce devlink, which can be used to configure port link types
(ethernet vs Infiniband, etc.), port splitting, and switch device
level attributes as a whole. From Jiri Pirko.
13) Hardware offload support for flower classifiers, from Amir Vadai.
14) Add "Local Checksum Offload". Basically, for a tunneled packet
the checksum of the outer header is 'constant' (because with the
checksum field filled into the inner protocol header, the payload
of the outer frame checksums to 'zero'), and we can take advantage
of that in various ways. From Edward Cree"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
bonding: fix bond_get_stats()
net: bcmgenet: fix dma api length mismatch
net/mlx4_core: Fix backward compatibility on VFs
phy: mdio-thunder: Fix some Kconfig typos
lan78xx: add ndo_get_stats64
lan78xx: handle statistics counter rollover
RDS: TCP: Remove unused constant
RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
net: smc911x: convert pxa dma to dmaengine
team: remove duplicate set of flag IFF_MULTICAST
bonding: remove duplicate set of flag IFF_MULTICAST
net: fix a comment typo
ethernet: micrel: fix some error codes
ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
bpf, dst: add and use dst_tclassid helper
bpf: make skb->tc_classid also readable
net: mvneta: bm: clarify dependencies
cls_bpf: reset class and reuse major in da
ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
ldmvsw: Add ldmvsw.c driver code
...
Core changes:
- The gpio_chip is now a *real device*. Until now the gpio chips
were just piggybacking the parent device or (gasp) floating in
space outside of the device model. We now finally make GPIO chips
devices. The gpio_chip will create a gpio_device which contains
a struct device, and this gpio_device struct is kept private.
Anything that needs to be kept private from the rest of the kernel
will gradually be moved over to the gpio_device.
- As a result of making the gpio_device a real device, we have added
resource management, so devm_gpiochip_add_data() will cut down on
overhead and reduce code lines. A huge slew of patches convert
almost all drivers in the subsystem to use this.
- Building on making the GPIO a real device, we add the first step
of a new userspace ABI: the GPIO character device. We take small
steps here, so we first add a pure *information* ABI and the tool
"lsgpio" that will list all GPIO devices on the system and all
lines on these devices. We can now discover GPIOs properly from
userspace. We still have not come up with a way to actually *use*
GPIOs from userspace.
- To encourage people to use the character device for the future,
we have it always-enabled when using GPIO. The old sysfs ABI is
still opt-in (and can be used in parallel), but is marked as
deprecated. We will keep it around for the foreseeable future,
but it will not be extended to cover ever more use cases.
Cleanup:
- Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
includes. This dates back to when GPIO was an opt-in feature and
no shared library even existed: just a header file with proper
prototypes was provided and all semantics were up to the arch to
implement. These patches make the GPIO chip even more a proper
device and cleans out leftovers of the old in-kernel API here
and there. Still some cruft is left but it's very little now.
- There is still some clamping of return values for .get() going
on, but we now return sane values in the vast majority of drivers
and the errorpath is sanitized. Some patches for powerpc, blackfin
and unicore still drop in.
- We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
implementations to use gpiochip_add_data() and cut down on code
lines.
- MPC8xxx is converted to use the generic GPIO helpers.
- ATH79 is converted to use the generic GPIO helpers.
New drivers:
- WinSystems WS16C48
- Acces 104-DIO-48E
- F81866 (a F7188x variant)
- Qoric (a MPC8xxx variant)
- TS-4800
- SPI serializers (pisosr): simple 74xx shift registers connected
to SPI to obtain a dirt-cheap output-only GPIO expander.
- Texas Instruments TPIC2810
- Texas Instruments TPS65218
- Texas Instruments TPS65912
- X-Gene (ARM64) standby GPIO controller
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Merge tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Linus Walleij:
"This is the bulk of GPIO changes for kernel v4.6. There is quite a
lot of interesting stuff going on.
The patches to other subsystems and arch-wide are ACKed as far as
possible, though I consider things like per-arch <asm/gpio.h> as
essentially a part of the GPIO subsystem so it should not be needed.
Core changes:
- The gpio_chip is now a *real device*. Until now the gpio chips
were just piggybacking the parent device or (gasp) floating in
space outside of the device model.
We now finally make GPIO chips devices. The gpio_chip will create
a gpio_device which contains a struct device, and this gpio_device
struct is kept private. Anything that needs to be kept private
from the rest of the kernel will gradually be moved over to the
gpio_device.
- As a result of making the gpio_device a real device, we have added
resource management, so devm_gpiochip_add_data() will cut down on
overhead and reduce code lines. A huge slew of patches convert
almost all drivers in the subsystem to use this.
- Building on making the GPIO a real device, we add the first step of
a new userspace ABI: the GPIO character device. We take small
steps here, so we first add a pure *information* ABI and the tool
"lsgpio" that will list all GPIO devices on the system and all
lines on these devices.
We can now discover GPIOs properly from userspace. We still have
not come up with a way to actually *use* GPIOs from userspace.
- To encourage people to use the character device for the future, we
have it always-enabled when using GPIO. The old sysfs ABI is still
opt-in (and can be used in parallel), but is marked as deprecated.
We will keep it around for the foreseeable future, but it will not
be extended to cover ever more use cases.
Cleanup:
- Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
includes.
This dates back to when GPIO was an opt-in feature and no shared
library even existed: just a header file with proper prototypes was
provided and all semantics were up to the arch to implement. These
patches make the GPIO chip even more a proper device and cleans out
leftovers of the old in-kernel API here and there.
Still some cruft is left but it's very little now.
- There is still some clamping of return values for .get() going on,
but we now return sane values in the vast majority of drivers and
the errorpath is sanitized. Some patches for powerpc, blackfin and
unicore still drop in.
- We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
implementations to use gpiochip_add_data() and cut down on code
lines.
- MPC8xxx is converted to use the generic GPIO helpers.
- ATH79 is converted to use the generic GPIO helpers.
New drivers:
- WinSystems WS16C48
- Acces 104-DIO-48E
- F81866 (a F7188x variant)
- Qoric (a MPC8xxx variant)
- TS-4800
- SPI serializers (pisosr): simple 74xx shift registers connected to
SPI to obtain a dirt-cheap output-only GPIO expander.
- Texas Instruments TPIC2810
- Texas Instruments TPS65218
- Texas Instruments TPS65912
- X-Gene (ARM64) standby GPIO controller"
* tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (194 commits)
Revert "Share upstreaming patches"
gpio: mcp23s08: Fix clearing of interrupt.
gpiolib: Fix comment referring to gpio_*() in gpiod_*()
gpio: pca953x: Fix pca953x_gpio_set_multiple() on 64-bit
gpio: xgene: Fix kconfig for standby GIPO contoller
gpio: Add generic serializer DT binding
gpio: uapi: use 0xB4 as ioctl() major
gpio: tps65912: fix bad merge
Revert "gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free"
gpio: omap: drop dev field from gpio_bank structure
gpio: mpc8xxx: Slightly update the code for better readability
gpio: mpc8xxx: Remove *read_reg and *write_reg from struct mpc8xxx_gpio_chip
gpio: mpc8xxx: Fixup setting gpio direction output
gpio: mcp23s08: Add support for mcp23s18
dt-bindings: gpio: altera: Fix altr,interrupt-type property
gpio: add driver for MEN 16Z127 GPIO controller
gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free
gpio: timberdale: Switch to devm_ioremap_resource()
gpio: ts4800: Add IMX51 dependency
gpiolib: rewrite gpiodev_add_to_list
...
but lots of architecture-specific changes.
* ARM:
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- various optimizations to the vgic save/restore code.
* PPC:
- enabled KVM-VFIO integration ("VFIO device")
- optimizations to speed up IPIs between vcpus
- in-kernel handling of IOMMU hypercalls
- support for dynamic DMA windows (DDW).
* s390:
- provide the floating point registers via sync regs;
- separated instruction vs. data accesses
- dirty log improvements for huge guests
- bugfixes and documentation improvements.
* x86:
- Hyper-V VMBus hypercall userspace exit
- alternative implementation of lowest-priority interrupts using vector
hashing (for better VT-d posted interrupt support)
- fixed guest debugging with nested virtualizations
- improved interrupt tracking in the in-kernel IOAPIC
- generic infrastructure for tracking writes to guest memory---currently
its only use is to speedup the legacy shadow paging (pre-EPT) case, but
in the future it will be used for virtual GPUs as well
- much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"One of the largest releases for KVM... Hardly any generic
changes, but lots of architecture-specific updates.
ARM:
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- various optimizations to the vgic save/restore code.
PPC:
- enabled KVM-VFIO integration ("VFIO device")
- optimizations to speed up IPIs between vcpus
- in-kernel handling of IOMMU hypercalls
- support for dynamic DMA windows (DDW).
s390:
- provide the floating point registers via sync regs;
- separated instruction vs. data accesses
- dirty log improvements for huge guests
- bugfixes and documentation improvements.
x86:
- Hyper-V VMBus hypercall userspace exit
- alternative implementation of lowest-priority interrupts using
vector hashing (for better VT-d posted interrupt support)
- fixed guest debugging with nested virtualizations
- improved interrupt tracking in the in-kernel IOAPIC
- generic infrastructure for tracking writes to guest
memory - currently its only use is to speedup the legacy shadow
paging (pre-EPT) case, but in the future it will be used for
virtual GPUs as well
- much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
KVM: x86: disable MPX if host did not enable MPX XSAVE features
arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
arm64: KVM: vgic-v3: Reset LRs at boot time
arm64: KVM: vgic-v3: Do not save an LR known to be empty
arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
arm64: KVM: vgic-v3: Avoid accessing ICH registers
KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
KVM: arm/arm64: vgic-v2: Reset LRs at boot time
KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
KVM: s390: allocate only one DMA page per VM
KVM: s390: enable STFLE interpretation only if enabled for the guest
KVM: s390: wake up when the VCPU cpu timer expires
KVM: s390: step the VCPU timer while in enabled wait
KVM: s390: protect VCPU cpu timer with a seqcount
KVM: s390: step VCPU cpu timer during kvm_run ioctl
...
GCC < 4.9 is unable to build this, saying:
arch/powerpc/mm/8xx_mmu.c:139:2: error: memory input 1 is not directly addressable
Change the one-element array into a simple variable to avoid this.
Fixes: 1458dd951f ("powerpc/8xx: Handle CPU6 ERRATA directly in mtspr() macro")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Freescale updates from Scott:
"Highlights include 8xx optimizations, 32-bit checksum optimizations,
86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt
bits, and minor fixes/cleanup."
flush/clean/invalidate _dcache_range() functions are all very
similar and are quite short. They are mainly used in __dma_sync()
perf_event locate them in the top 3 consumming functions during
heavy ethernet activity
They are good candidate for inlining, as __dma_sync() does
almost nothing but calling them
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
clear_pages() is never used expect by clear_page, and PPC32 is the
only architecture (still) having this function. Neither PPC64 nor
any other architecture has it.
This patch removes clear_pages() and moves clear_page() function
inline (same as PPC64) as it only is a few isns
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
This patch adds inline functions to use dcbz, dcbi, dcbf, dcbst
from C functions
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
CPU6 ERRATA is now handled directly in mtspr(), so we can use the
standard set_dec() fonction in all cases.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
MPC8xx has an ERRATA on the use of mtspr() for some registers
This patch includes the ERRATA handling directly into mtspr() macro
so that mtspr() users don't need to bother about that errata
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
Add missing SPRN defines into reg_8xx.h
Some of them are defined in mmu-8xx.h, so we include mmu-8xx.h in
reg_8xx.h, for that we remove references to PAGE_SHIFT in mmu-8xx.h
to have it self sufficient, as includers of reg_8xx.h don't all
include asm/page.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
ioremap_base is not initialised and is nowhere used so remove it
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
The fixmap related functions try to map kernel pages that are
already mapped through Large TLBs. pte_offset_kernel() has to
return NULL for LTLBs, otherwise the caller will try to access
level 2 table which doesn't exist
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
Merge the ftrace changes to support -mprofile-kernel on ppc64le. This is
a prerequisite for live patching, the support for which will be merged
via the livepatch tree based on this topic branch.
Power8 supports a large number of events in each susbystem so when a
user runs:
perf stat -e branch-instructions sleep 1
perf stat -e L1-dcache-loads sleep 1
it is not clear as to which PMU events were monitored.
Export the generic hardware and cache perf events for Power8 to sysfs,
so users can precisely determine the PMU event monitored by the generic
event.
Eg:
cat /sys/bus/event_source/devices/cpu/events/branch-instructions
event=0x10068
$ cat /sys/bus/event_source/devices/cpu/events/L1-dcache-loads
event=0x100ee
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We used the PME_ prefix earlier to avoid some macro/variable name
collisions. We have since changed the way we define/use the event
macros so we no longer need the prefix.
By dropping the prefix, we keep the the event macros consistent with
their official names.
Reported-by: Michael Ellerman <ellerman@au1.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
csum_partial is often called for small fixed length packets
for which it is suboptimal to use the generic csum_partial()
function.
For instance, in my configuration, I got:
* One place calling it with constant len 4
* Seven places calling it with constant len 8
* Three places calling it with constant len 14
* One place calling it with constant len 20
* One place calling it with constant len 24
* One place calling it with constant len 32
This patch renames csum_partial() to __csum_partial() and
implements csum_partial() as a wrapper inline function which
* uses csum_add() for small 16bits multiple constant length
* uses ip_fast_csum() for other 32bits multiple constant
* uses __csum_partial() in all other cases
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- Various optimizations to the vgic save/restore code
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Merge tag 'kvm-arm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/ARM updates for 4.6
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- Various optimizations to the vgic save/restore code
Conflicts:
include/uapi/linux/kvm.h
The hcalls introduced for cxl use a possible new value:
H_STATE (invalid state).
Co-authored-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PFs are enumerated on PCI bus, while VFs are created by PF's driver.
In EEH recovery, it has two cases:
1. Device and driver is EEH aware, error handlers are called.
2. Device and driver is not EEH aware, un-plug the device and plug it again
by enumerating it.
The special thing happens on the second case. For a PF, we could use the
original pci core to enumerate the bus, while for VF we need to record the
VFs which aer un-plugged then plug it again.
Also The patch caches the VF index in pci_dn, which can be used to
calculate VF's bus, device and function number. Those information helps to
locate the VF's PCI device instance when doing hotplug during EEH recovery
if necessary.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
After PE reset, OPAL API opal_pci_reinit() is called on all devices
contained in the PE to reinitialize them. While skiboot is not aware of
VFs, we have to implement the function in kernel to reinitialize VFs after
reset on PE for VFs.
In this patch, two functions pnv_pci_fixup_vf_mps() and
pnv_eeh_restore_vf_config() both manipulate the MPS of the VF, since for a
VF it has three cases.
1. Normal creation for a VF
In this case, pnv_pci_fixup_vf_mps() is called to make the MPS a proper
value compared with its parent.
2. EEH recovery without VF removed
In this case, MPS is stored in pci_dn and pnv_eeh_restore_vf_config() is
called to restore it and reinitialize other part.
3. EEH recovery with VF removed
In this case, VF will be removed then re-created. Both functions are
called. First pnv_pci_fixup_vf_mps() is called to store the proper MPS
to pci_dn and then pnv_eeh_restore_vf_config() is called to do proper
thing.
This introduces two functions: pnv_pci_fixup_vf_mps() to fixup the VF's
MPS to make sure it is equal to parent's and store this value in pci_dn
for future use. pnv_eeh_restore_vf_config() to re-initialize on VF by
restoring MPS, disabling completion timeout, enabling SERR, etc.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
PEs for VFs don't have primary bus. So they have to have their own reset
backend, which is used during EEH recovery. The patch implements the reset
backend for VF's PE by issuing FLR or AF FLR to the VFs, which are contained
in the PE.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This creates PEs for VFs in the weak function pcibios_bus_add_device().
Those PEs for VFs are identified with newly introduced flag EEH_PE_VF
so that we treat them differently during EEH recovery.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
VFs and their corresponding pdn are created and released dynamically
when their PF's SRIOV capability is enabled and disabled. This creates
and releases EEH devices for VFs when creating and releasing their pdn
instances, which means EEH devices and pdn instances have same life
cycle. Also, VF's EEH device is identified by (struct eeh_dev::physfn).
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Acked-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
For a long time all architectures implement the pci_dma_* functions using
the generic DMA API, and they all use the same header to do so.
Move this header, pci-dma-compat.h, to include/linux and include it from
the generic pci.h instead of having each arch duplicate this include.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The gcc switch -mprofile-kernel defines a new ABI for calling _mcount()
very early in the function with minimal overhead.
Although mprofile-kernel has been available since GCC 3.4, there were
bugs which were only fixed recently. Currently it is known to work in
GCC 4.9, 5 and 6.
Additionally there are two possible code sequences generated by the
flag, the first uses mflr/std/bl and the second is optimised to omit the
std. Currently only gcc 6 has the optimised sequence. This patch
supports both sequences.
Initial work started by Vojtech Pavlik, used with permission.
Key changes:
- rework _mcount() to work for both the old and new ABIs.
- implement new versions of ftrace_caller() and ftrace_graph_caller()
which deal with the new ABI.
- updates to __ftrace_make_nop() to recognise the new mcount calling
sequence.
- updates to __ftrace_make_call() to recognise the nop'ed sequence.
- implement ftrace_modify_call().
- updates to the module loader to surpress the toc save in the module
stub when calling mcount with the new ABI.
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When a module is loaded, calls out to the kernel go via a stub which is
generated at runtime. One of these stubs is used to call _mcount(),
which is the default target of tracing calls generated by the compiler
with -pg.
If dynamic ftrace is enabled (which it typically is), another stub is
used to call ftrace_caller(), which is the target of tracing calls when
ftrace is actually active.
ftrace then wants to disable the calls to _mcount() at module startup,
and enable/disable the calls to ftrace_caller() when enabling/disabling
tracing - all of these it does by patching the code.
As part of that code patching, the ftrace code wants to confirm that the
branch it is about to modify, is in fact a call to a module stub which
calls _mcount() or ftrace_caller().
Currently it does that by inspecting the instructions and confirming
they are what it expects. Although that works, the code to do it is
pretty intricate because it requires lots of knowledge about the exact
format of the stub.
We can make that process easier by marking the generated stubs with a
magic value, and then looking for that magic value. Altough this is not
as rigorous as the current method, I believe it is sufficient in
practice.
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently we generate the module stub for ftrace_caller() at the bottom
of apply_relocate_add(). However apply_relocate_add() is potentially
called more than once per module, which means we will try to generate
the ftrace_caller() stub multiple times.
Although the current code deals with that correctly, ie. it only
generates a stub the first time, it would be clearer to only try to
generate the stub once.
Note also on first reading it may appear that we generate a different
stub for each section that requires relocation, but that is not the
case. The code in stub_for_addr() that searches for an existing stub
uses sechdrs[me->arch.stubs_section], ie. the single stub section for
this module.
A cleaner approach is to only generate the ftrace_caller() stub once,
from module_finalize(). Although the original code didn't check to see
if the stub was actually generated correctly, it seems prudent to add a
check, so do that. And an additional benefit is we can clean the ifdefs
up a little.
Finally we must propagate the const'ness of some of the pointers passed
to module_finalize(), but that is also an improvement.
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move the logic to work out the kernel toc pointer into a header. This is
a good cleanup, and also means we can use it elsewhere in future.
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Support Freescale E6500 core-based platforms, like t4240.
Support disabling/enabling individual CPU thread dynamically.
Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Freescale E500MC and E5500 core-based platforms, like P4080, T1040,
support disabling/enabling CPU dynamically.
This patch adds this feature on those platforms.
Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Tang Yuantian <Yuantian.Tang@feescale.com>
[scottwood: removed unused pr_fmt]
Signed-off-by: Scott Wood <oss@buserror.net>
There is a RCPM (Run Control/Power Management) in Freescale QorIQ
series processors. The device performs tasks associated with device
run control and power management.
The driver implements some features: mask/unmask irq, enter/exit low
power states, freeze time base, etc.
Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Tang Yuantian <Yuantian.Tang@freescale.com>
[scottwood: remove __KERNEL__ ifdef]
Signed-off-by: Scott Wood <oss@buserror.net>
Various e500 core have different cache architecture, so they
need different cache flush operations. Therefore, add a callback
function cpu_flush_caches to the struct cpu_spec. The cache flush
operation for the specific kind of e500 is selected at init time.
The callback function will flush all caches inside the current cpu.
Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Tang Yuantian <Yuantian.Tang@feescale.com>
Signed-off-by: Scott Wood <oss@buserror.net>
On e6500, in the case of cpu hotplug, either thread in one core
may be the first thread initilzing the TLB1. The subsequent threads
must not setup it again.
The code is derived from the comment of Scott Wood.
Signed-off-by: Chenhui Zhao <chenhui.zhao@freescale.com>
Signed-off-by: Scott Wood <oss@buserror.net>
Simplify csum_add(a, b) in case a or b is constant 0
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
In several architectures, ip_fast_csum() is inlined
There are functions like ip_send_check() which do nothing
much more than calling ip_fast_csum().
Inlining ip_fast_csum() allows the compiler to optimise better
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[scottwood: whitespace and cast fixes]
Signed-off-by: Scott Wood <oss@buserror.net>
The powerpc64 checksum wrapper functions adds csum_and_copy_to_user()
which otherwise is implemented in include/net/checksum.h by using
csum_partial() then copy_to_user()
Those two wrapper fonctions are also applicable to powerpc32 as it is
based on the use of csum_partial_copy_generic() which also
exists on powerpc32
This patch renames arch/powerpc/lib/checksum_wrappers_64.c to
arch/powerpc/lib/checksum_wrappers.c and
makes it non-conditional to CONFIG_WORD_SIZE
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
addc uses carry so xer is clobbered in csum_add()
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
This is needed so that we can support both hash and radix page table
using single kernel. Radix kernel uses a 4 level table.
We now use physical address in upper page table tree levels. Even though
they are aligned to their size, for the masked bits we use the
bit positions as per PowerISA 3.0.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We remove real_pte_t out of STRICT_MM_TYPESCHECK.
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We move the page table accessors into a separate header. We will
later add a big endian variant of the table which is needed for radix.
No functionality change only code movement.
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds the ability to be able to save the VSX registers to the
thread struct without giving up (disabling the facility) next time the
process returns to userspace.
This patch builds on a previous optimisation for the FPU and VEC registers
in the thread copy path to avoid a possibly pointless reload of VSX state.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds the ability to be able to save the VEC registers to the
thread struct without giving up (disabling the facility) next time the
process returns to userspace.
This patch builds on a previous optimisation for the FPU registers in the
thread copy path to avoid a possibly pointless reload of VEC state.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Simon Guo