A bus lock is acquired through either split locked access to writeback
(WB) memory or any locked access to non-WB memory. It is typically >1000
cycles slower than an atomic operation within a cache and can also
disrupts performance on other cores.
Virtual Machines can exploit bus locks to degrade the performance of
system. To address this kind of performance DOS attack coming from the
VMs, bus lock VM exit is introduced in KVM and it can report the bus
locks detected in guest. If enabled in KVM, it would exit to the
userspace to let the user enforce throttling policies once bus locks
acquired in VMs.
The availability of bus lock VM exit can be detected through the
KVM_CAP_X86_BUS_LOCK_EXIT. The returned bitmap contains the potential
policies supported by KVM. The field KVM_BUS_LOCK_DETECTION_EXIT in
bitmap is the only supported strategy at present. It indicates that KVM
will exit to userspace to handle the bus locks.
This patch adds a ratelimit on the bus locks acquired in guest as a
mitigation policy.
Introduce a new field "bus_lock_ratelimit" to record the limited speed
of bus locks in the target VM. The user can specify it through the
"bus-lock-ratelimit" as a machine property. In current implementation,
the default value of the speed is 0 per second, which means no
restrictions on the bus locks.
As for ratelimit on detected bus locks, simply set the ratelimit
interval to 1s and restrict the quota of bus lock occurence to the value
of "bus_lock_ratelimit". A potential alternative is to introduce the
time slice as a property which can help the user achieve more precise
control.
The detail of bus lock VM exit can be found in spec:
https://software.intel.com/content/www/us/en/develop/download/intel-architecture-instruction-set-extensions-programming-reference.html
Signed-off-by: Chenyi Qiang <chenyi.qiang@intel.com>
Message-Id: <20210521043820.29678-1-chenyi.qiang@intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Change to -std=gnu11.
Replace QEMU_GENERIC with _Generic.
Remove configure detect of _Static_assert.
# gpg: Signature made Wed 16 Jun 2021 02:32:32 BST
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A 05C0 64DF 38E8 AF7E 215F
* remotes/rth-gitlab/tags/pull-c11-20210615:
configure: Remove probe for _Static_assert
qemu/compiler: Remove QEMU_GENERIC
include/qemu/lockable: Use _Generic instead of QEMU_GENERIC
util: Use unique type for QemuRecMutex in thread-posix.h
util: Pass file+line to qemu_rec_mutex_unlock_impl
util: Use real functions for thread-posix QemuRecMutex
softfloat: Use _Generic instead of QEMU_GENERIC
configure: Use -std=gnu11
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Currently the ARM SVE helper code defines locally some utility
functions for swapping 16-bit halfwords within 32-bit or 64-bit
values and for swapping 32-bit words within 64-bit values,
parallel to the byte-swapping bswap16/32/64 functions.
We want these also for the ARM MVE code, and they're potentially
generally useful for other targets, so move them to bitops.h.
(We don't put them in bswap.h with the bswap* functions because
they are implemented in terms of the rotate operations also
defined in bitops.h, and including bitops.h from bswap.h seems
better avoided.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210614151007.4545-17-peter.maydell@linaro.org
This is both more and less complicated than our expansion
using __builtin_choose_expr and __builtin_types_compatible_p.
The expansion through QEMU_MAKE_LOCKABLE_ doesn't work because
we're not emumerating all of the types within the same _Generic,
which results in errors about unhandled cases. We must also
handle void* explicitly, so that the NULL constant can be used.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210614233143.1221879-7-richard.henderson@linaro.org>
At some point during the development of tcg_constant_*, I changed
my mind about whether such temps should be able to be passed to
tcg_temp_free_*. The final version committed allows this, but the
commentary was not updated to match.
Fixes: c0522136ad
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These variables belong to the jit side, not the user side.
Since tcg_init_ctx is no longer used outside of tcg/, move
the declaration to tcg-internal.h.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Suggested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Shortly, the full code_gen_buffer will only be visible
to region.c, so move in_code_gen_buffer out-of-line.
Move the debugging versions of tcg_splitwx_to_{rx,rw}
to region.c as well, so that the compiler gets to see
the implementation of in_code_gen_buffer.
This leaves exactly one use of in_code_gen_buffer outside
of region.c, in cpu_restore_state. Which, being on the
exception path, is not performance critical.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Start removing the include of hw/boards.h from tcg/.
Pass down the max_cpus value from tcg_init_machine,
where we have the MachineState already.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Buffer management is integral to tcg. Do not leave the allocation
to code outside of tcg/. This is code movement, with further
cleanups to follow.
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This patch implements the vq notification mapping support for
vhost-vDPA. This is simply done by using mmap()/munmap() for the
vhost-vDPA fd during device start/stop. For the device without
notification mapping support, we fall back to eventfd based
notification gracefully.
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Second RISC-V PR for QEMU 6.1
- Update the PLIC and CLINT DT bindings
- Improve documentation for RISC-V machines
- Support direct kernel boot for microchip_pfsoc
- Fix WFI exception behaviour
- Improve CSR printing
- Initial support for the experimental Bit Manip extension
# gpg: Signature made Tue 08 Jun 2021 01:28:27 BST
# gpg: using RSA key F6C4AC46D4934868D3B8CE8F21E10D29DF977054
# gpg: Good signature from "Alistair Francis <alistair@alistair23.me>" [full]
# Primary key fingerprint: F6C4 AC46 D493 4868 D3B8 CE8F 21E1 0D29 DF97 7054
* remotes/alistair/tags/pull-riscv-to-apply-20210608-1: (32 commits)
target/riscv: rvb: add b-ext version cpu option
target/riscv: rvb: support and turn on B-extension from command line
target/riscv: rvb: add/shift with prefix zero-extend
target/riscv: rvb: address calculation
target/riscv: rvb: generalized or-combine
target/riscv: rvb: generalized reverse
target/riscv: rvb: rotate (left/right)
target/riscv: rvb: shift ones
target/riscv: rvb: single-bit instructions
target/riscv: add gen_shifti() and gen_shiftiw() helper functions
target/riscv: rvb: sign-extend instructions
target/riscv: rvb: min/max instructions
target/riscv: rvb: pack two words into one register
target/riscv: rvb: logic-with-negate
target/riscv: rvb: count bits set
target/riscv: rvb: count leading/trailing zeros
target/riscv: reformat @sh format encoding for B-extension
target/riscv: Pass the same value to oprsz and maxsz.
target/riscv/pmp: Add assert for ePMP operations
target/riscv: Dump CSR mscratch/sscratch/satp
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Long story short, we need a space here for the reference to work
correctly.
Longer story:
Without the space, kerneldoc generates a line like this:
one of :c:type:`MemoryListener.region_add\(\) <MemoryListener>`,:c:type:`MemoryListener.region_del\(\)
Sphinx does not process the role information correctly, so we get this
(my pseudo-notation) construct:
<text>,:c:type:</text>
<reference target="MemoryListener">MemoryListener.region_del()</reference>
which does not reference the desired entity, and leaves some extra junk
in the rendered output. See
https://qemu-project.gitlab.io/qemu/devel/memory.html#c.MemoryListener
member log_start for an example of the broken output as it looks today.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210511192950.2061326-1-jsnow@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
# gpg: Signature made Fri 04 Jun 2021 08:26:16 BST
# gpg: using RSA key EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F 3562 EF04 965B 398D 6211
* remotes/jasowang/tags/net-pull-request:
MAINTAINERS: Added eBPF maintainers information.
docs: Added eBPF documentation.
virtio-net: Added eBPF RSS to virtio-net.
ebpf: Added eBPF RSS loader.
ebpf: Added eBPF RSS program.
net: Added SetSteeringEBPF method for NetClientState.
net/tap: Added TUNSETSTEERINGEBPF code.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Change the parser to put the values into a QDict and pass them
to a callback. qemu_config_parse's QemuOpts creation is
itself turned into a callback function.
This is useful for -readconfig to support keyval-based options;
getting a QDict from the parser removes a roundtrip from
QDict to QemuOpts and then back to QDict.
Unfortunately there is a disadvantage in that semantic errors will
point to the last line of the group, because the entries of the QDict
do not have a location attached.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210524105752.3318299-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When RSS is enabled the device tries to load the eBPF program
to select RX virtqueue in the TUN. If eBPF can be loaded
the RSS will function also with vhost (works with kernel 5.8 and later).
Software RSS is used as a fallback with vhost=off when eBPF can't be loaded
or when hash population requested by the guest.
Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
For now, that method supported only by Linux TAP.
Linux TAP uses TUNSETSTEERINGEBPF ioctl.
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Rename to parts$N_modrem. This was the last use of a lot
of the legacy infrastructure, so remove it as required.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The float128 implementation is straight-forward.
Unfortuantely, we don't have any tests we can simply adjust/unlock.
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210517142739.38597-24-david@redhat.com>
[rth: Update for changed parts_minmax return value]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch splits the vcpu init and destroy functions into a generic and
an architecture specific portion. This also allows us to move the generic
functions into the generic hvf code, removing exported functions.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-8-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves a few internal struct and constant defines over.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-5-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves CPU and memory operations over. While at it, make sure
the code is consumable on non-i386 systems.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-4-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Until now, Hypervisor.framework has only been available on x86_64 systems.
With Apple Silicon shipping now, it extends its reach to aarch64. To
prepare for support for multiple architectures, let's start moving common
code out into its own accel directory.
This patch moves assert_hvf_ok() and introduces generic build infrastructure.
Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210519202253.76782-2-agraf@csgraf.de
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The official punctuation for Arm CPU names uses a hyphen, like
"Cortex-A9". We mostly follow this, but in a few places usage
without the hyphen has crept in. Fix those so we consistently
use the same way of writing the CPU name.
This commit was created with:
git grep -z -l 'Cortex ' | xargs -0 sed -i 's/Cortex /Cortex-/'
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20210527095152.10968-1-peter.maydell@linaro.org
Currently we allow board models to specify the initial value of the
Secure VTOR register, using an init-svtor property on the TYPE_ARMV7M
object which is plumbed through to the CPU. Allow board models to
also specify the initial value of the Non-secure VTOR via a similar
init-nsvtor property.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210520152840.24453-10-peter.maydell@linaro.org
