Hi,
At Linux Plumbers, a few dozen of us gathered together to discuss how
to expose what tests subsystem maintainers would like to run for every
patch submitted or when CI runs tests. We agreed on a mock up of a
yaml template to start gathering info. The yaml file could be
temporarily stored on kernelci.org until a more permanent home could
be found. Attached is a template to start the conversation.
Longer story.
The current problem is CI systems are not unanimous about what tests
they run on submitted patches or git branches. This makes it
difficult to figure out why a test failed or how to reproduce.
Further, it isn't always clear what tests a normal contributor should
run before posting patches.
It has been long communicated that the tests LTP, xfstest and/or
kselftests should be the tests to run. However, not all maintainers
use those tests for their subsystems. I am hoping to either capture
those tests or find ways to convince them to add their tests to the
preferred locations.
The goal is for a given subsystem (defined in MAINTAINERS), define a
set of tests that should be run for any contributions to that
subsystem. The hope is the collective CI results can be triaged
collectively (because they are related) and even have the numerous
flakes waived collectively (same reason) improving the ability to
find and debug new test failures. Because the tests and process are
known, having a human help debug any failures becomes easier.
The plan is to put together a minimal yaml template that gets us going
(even if it is not optimized yet) and aim for about a dozen or so
subsystems. At that point we should have enough feedback to promote
this more seriously and talk optimizations.
Feedback encouraged.
Cheers,
Don
---
# List of tests by subsystem
#
# Tests should adhere to KTAP definitions for results
#
# Description of section entries
#
# maintainer: test maintainer - name <email>
# list: mailing list for discussion
# version: stable version of the test
# dependency: necessary distro package for testing
# test:
# path: internal git path or url to fetch from
# cmd: command to run; ability to run locally
# param: additional param necessary to run test
# hardware: hardware necessary for validation
#
# Subsystems (alphabetical)
KUNIT TEST:
maintainer:
- name: name1
email: email1
- name: name2
email: email2
list:
version:
dependency:
- dep1
- dep2
test:
- path: tools/testing/kunit
cmd:
param:
- path:
cmd:
param:
hardware: none
This series is a follow-up to Joey's Permission Overlay Extension (POE)
series [1] that recently landed on mainline. The goal is to improve the
way we handle the register that governs which pkeys/POIndex are
accessible (POR_EL0) during signal delivery. As things stand, we may
unexpectedly fail to write the signal frame on the stack because POR_EL0
is not reset before the uaccess operations. See patch 3 for more details
and the main changes this series brings.
A similar series landed recently for x86/MPK [2]; the present series
aims at aligning arm64 with x86. Worth noting: once the signal frame is
written, POR_EL0 is still set to POR_EL0_INIT, granting access to pkey 0
only. This means that a program that sets up an alternate signal stack
with a non-zero pkey will need some assembly trampoline to set POR_EL0
before invoking the real signal handler, as discussed here [3]. This is
not ideal, but it makes experimentation with pkeys in signal handlers
possible while waiting for a potential interface to control the pkey
state when delivering a signal. See Pierre's reply [4] for more
information about use-cases and a potential interface.
The x86 series also added kselftests to ensure that no spurious SIGSEGV
occurs during signal delivery regardless of which pkey is accessible at
the point where the signal is delivered. This series adapts those
kselftests to allow running them on arm64 (patch 4-5).
Finally patch 2 is a clean-up following feedback on Joey's series [5].
I have tested this series on arm64 and x86_64 (booting and running the
protection_keys and pkey_sighandler_tests mm kselftests).
v1..v2:
* In setup_rt_frame(), ensured that POR_EL0 is reset to its original
value if we fail to deliver the signal (addresses Catalin's concern [6]).
* Renamed *unpriv_access* to *user_access* in patch 3 (suggestion from
Dave).
* Made what patch 1-2 do explicit in the commit message body (suggestion
from Dave).
- Kevin
[1] https://lore.kernel.org/linux-arm-kernel/20240822151113.1479789-1-joey.goul…
[2] https://lore.kernel.org/lkml/20240802061318.2140081-1-aruna.ramakrishna@ora…
[3] https://lore.kernel.org/lkml/CABi2SkWxNkP2O7ipkP67WKz0-LV33e5brReevTTtba6oK…
[4] https://lore.kernel.org/linux-arm-kernel/87plns8owh.fsf@arm.com/
[5] https://lore.kernel.org/linux-arm-kernel/20241015114116.GA19334@willie-the-…
[6] https://lore.kernel.org/linux-arm-kernel/Zw6D2waVyIwYE7wd@arm.com/
Cc: akpm(a)linux-foundation.org
Cc: anshuman.khandual(a)arm.com
Cc: aruna.ramakrishna(a)oracle.com
Cc: broonie(a)kernel.org
Cc: catalin.marinas(a)arm.com
Cc: dave.hansen(a)linux.intel.com
Cc: dave.martin(a)arm.com
Cc: jeffxu(a)chromium.org
Cc: joey.gouly(a)arm.com
Cc: pierre.langlois(a)arm.com
Cc: shuah(a)kernel.org
Cc: sroettger(a)google.com
Cc: will(a)kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Cc: x86(a)kernel.org
Kevin Brodsky (5):
arm64: signal: Remove unused macro
arm64: signal: Remove unnecessary check when saving POE state
arm64: signal: Improve POR_EL0 handling to avoid uaccess failures
selftests/mm: Use generic pkey register manipulation
selftests/mm: Enable pkey_sighandler_tests on arm64
arch/arm64/kernel/signal.c | 95 +++++++++++++---
tools/testing/selftests/mm/Makefile | 8 +-
tools/testing/selftests/mm/pkey-arm64.h | 1 +
tools/testing/selftests/mm/pkey-x86.h | 2 +
.../selftests/mm/pkey_sighandler_tests.c | 101 +++++++++++++-----
5 files changed, 162 insertions(+), 45 deletions(-)
--
2.43.0
Unmapping virtual machine guest memory from the host kernel's direct map
is a successful mitigation against Spectre-style transient execution
issues: If the kernel page tables do not contain entries pointing to
guest memory, then any attempted speculative read through the direct map
will necessarily be blocked by the MMU before any observable
microarchitectural side-effects happen. This means that Spectre-gadgets
and similar cannot be used to target virtual machine memory. Roughly 60%
of speculative execution issues fall into this category [1, Table 1].
This patch series extends guest_memfd with the ability to remove its
memory from the host kernel's direct map, to be able to attain the above
protection for KVM guests running inside guest_memfd.
=== Changes to v2 ===
- Handle direct map removal for physically contiguous pages in arch code
(Mike R.)
- Track the direct map state in guest_memfd itself instead of at the
folio level, to prepare for huge pages support (Sean C.)
- Allow configuring direct map state of not-yet faulted in memory
(Vishal A.)
- Pay attention to alignment in ftrace structs (Steven R.)
Most significantly, I've reduced the patch series to focus only on
direct map removal for guest_memfd for now, leaving the whole "how to do
non-CoCo VMs in guest_memfd" for later. If this separation is
acceptable, then I think I can drop the RFC tag in the next revision
(I've mainly kept it here because I'm not entirely sure what to do with
patches 3 and 4).
=== Implementation ===
This patch series introduces a new flag to the KVM_CREATE_GUEST_MEMFD
that causes guest_memfd to remove its pages from the host kernel's
direct map immediately after population/preparation. It also adds
infrastructure for tracking the direct map state of all gmem folios
inside the guest_memfd inode. Storing this information in the inode has
the advantage that the code is ready for future hugepages extensions,
where only removing/reinserting direct map entries for sub-ranges of a
huge folio is a valid usecase, and it allows pre-configuring the direct
map state of not-yet faulted in parts of memory (for example, when the
VMM is receiving a RX virtio buffer from the guest).
=== Summary ===
Patch 1 (from Mike Rapoport) adds arch APIs for manipulating the direct
map for ranges of physically contiguous pages, which are used by
guest_memfd in follow up patches. Patch 2 adds the
KVM_GMEM_NO_DIRECT_MAP flag and the logic for configuring direct map
state of freshly prepared folios. Patches 3 and 4 mainly serve an
illustrative purpose, to show how the framework from patch 2 can be
extended with routines for runtime direct map manipulation. Patches 5
and 6 deal with documentation and self-tests respectively.
[1]: https://download.vusec.net/papers/quarantine_raid23.pdf
[RFC v1]: https://lore.kernel.org/kvm/20240709132041.3625501-1-roypat@amazon.co.uk/
[RFC v2]: https://lore.kernel.org/kvm/20240910163038.1298452-1-roypat@amazon.co.uk/
Mike Rapoport (Microsoft) (1):
arch: introduce set_direct_map_valid_noflush()
Patrick Roy (5):
kvm: gmem: add flag to remove memory from kernel direct map
kvm: gmem: implement direct map manipulation routines
kvm: gmem: add trace point for direct map state changes
kvm: document KVM_GMEM_NO_DIRECT_MAP flag
kvm: selftests: run gmem tests with KVM_GMEM_NO_DIRECT_MAP set
Documentation/virt/kvm/api.rst | 14 +
arch/arm64/include/asm/set_memory.h | 1 +
arch/arm64/mm/pageattr.c | 10 +
arch/loongarch/include/asm/set_memory.h | 1 +
arch/loongarch/mm/pageattr.c | 21 ++
arch/riscv/include/asm/set_memory.h | 1 +
arch/riscv/mm/pageattr.c | 15 +
arch/s390/include/asm/set_memory.h | 1 +
arch/s390/mm/pageattr.c | 11 +
arch/x86/include/asm/set_memory.h | 1 +
arch/x86/mm/pat/set_memory.c | 8 +
include/linux/set_memory.h | 6 +
include/trace/events/kvm.h | 22 ++
include/uapi/linux/kvm.h | 2 +
.../testing/selftests/kvm/guest_memfd_test.c | 2 +-
.../kvm/x86_64/private_mem_conversions_test.c | 7 +-
virt/kvm/guest_memfd.c | 280 +++++++++++++++++-
17 files changed, 384 insertions(+), 19 deletions(-)
base-commit: 5cb1659f412041e4780f2e8ee49b2e03728a2ba6
--
2.47.0
xtheadvector is a custom extension that is based upon riscv vector
version 0.7.1 [1]. All of the vector routines have been modified to
support this alternative vector version based upon whether xtheadvector
was determined to be supported at boot.
vlenb is not supported on the existing xtheadvector hardware, so a
devicetree property thead,vlenb is added to provide the vlenb to Linux.
There is a new hwprobe key RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0 that is
used to request which thead vendor extensions are supported on the
current platform. This allows future vendors to allocate hwprobe keys
for their vendor.
Support for xtheadvector is also added to the vector kselftests.
Signed-off-by: Charlie Jenkins <charlie(a)rivosinc.com>
[1] https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361…
---
This series is a continuation of a different series that was fragmented
into two other series in an attempt to get part of it merged in the 6.10
merge window. The split-off series did not get merged due to a NAK on
the series that added the generic riscv,vlenb devicetree entry. This
series has converted riscv,vlenb to thead,vlenb to remedy this issue.
The original series is titled "riscv: Support vendor extensions and
xtheadvector" [3].
The series titled "riscv: Extend cpufeature.c to detect vendor
extensions" is still under development and this series is based on that
series! [4]
I have tested this with an Allwinner Nezha board. I used SkiffOS [1] to
manage building the image, but upgraded the U-Boot version to Samuel
Holland's more up-to-date version [2] and changed out the device tree
used by U-Boot with the device trees that are present in upstream linux
and this series. Thank you Samuel for all of the work you did to make
this task possible.
[1] https://github.com/skiffos/SkiffOS/tree/master/configs/allwinner/nezha
[2] https://github.com/smaeul/u-boot/commit/2e89b706f5c956a70c989cd31665f1429e9…
[3] https://lore.kernel.org/all/20240503-dev-charlie-support_thead_vector_6_9-v…
[4] https://lore.kernel.org/lkml/20240719-support_vendor_extensions-v3-4-0af758…
---
Changes in v10:
- In DT probing disable vector with new function to clear vendor
extension bits for xtheadvector
- Add ghostwrite mitigations for c9xx CPUs. This disables xtheadvector
unless mitigations=off is set as a kernel boot arg
- Link to v9: https://lore.kernel.org/r/20240806-xtheadvector-v9-0-62a56d2da5d0@rivosinc.…
Changes in v9:
- Rebase onto palmer's for-next
- Fix sparse error in arch/riscv/kernel/vendor_extensions/thead.c
- Fix maybe-uninitialized warning in arch/riscv/include/asm/vendor_extensions/vendor_hwprobe.h
- Wrap some long lines
- Link to v8: https://lore.kernel.org/r/20240724-xtheadvector-v8-0-cf043168e137@rivosinc.…
Changes in v8:
- Rebase onto palmer's for-next
- Link to v7: https://lore.kernel.org/r/20240724-xtheadvector-v7-0-b741910ada3e@rivosinc.…
Changes in v7:
- Add defs for has_xtheadvector_no_alternatives() and has_xtheadvector()
when vector disabled. (Palmer)
- Link to v6: https://lore.kernel.org/r/20240722-xtheadvector-v6-0-c9af0130fa00@rivosinc.…
Changes in v6:
- Fix return type of is_vector_supported()/is_xthead_supported() to be bool
- Link to v5: https://lore.kernel.org/r/20240719-xtheadvector-v5-0-4b485fc7d55f@rivosinc.…
Changes in v5:
- Rebase on for-next
- Link to v4: https://lore.kernel.org/r/20240702-xtheadvector-v4-0-2bad6820db11@rivosinc.…
Changes in v4:
- Replace inline asm with C (Samuel)
- Rename VCSRs to CSRs (Samuel)
- Replace .insn directives with .4byte directives
- Link to v3: https://lore.kernel.org/r/20240619-xtheadvector-v3-0-bff39eb9668e@rivosinc.…
Changes in v3:
- Add back Heiko's signed-off-by (Conor)
- Mark RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0 as a bitmask
- Link to v2: https://lore.kernel.org/r/20240610-xtheadvector-v2-0-97a48613ad64@rivosinc.…
Changes in v2:
- Removed extraneous references to "riscv,vlenb" (Jess)
- Moved declaration of "thead,vlenb" into cpus.yaml and added
restriction that it's only applicable to thead cores (Conor)
- Check CONFIG_RISCV_ISA_XTHEADVECTOR instead of CONFIG_RISCV_ISA_V for
thead,vlenb (Jess)
- Fix naming of hwprobe variables (Evan)
- Link to v1: https://lore.kernel.org/r/20240609-xtheadvector-v1-0-3fe591d7f109@rivosinc.…
---
Charlie Jenkins (13):
dt-bindings: riscv: Add xtheadvector ISA extension description
dt-bindings: cpus: add a thead vlen register length property
riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree
riscv: Add thead and xtheadvector as a vendor extension
riscv: vector: Use vlenb from DT for thead
riscv: csr: Add CSR encodings for CSR_VXRM/CSR_VXSAT
riscv: Add xtheadvector instruction definitions
riscv: vector: Support xtheadvector save/restore
riscv: hwprobe: Add thead vendor extension probing
riscv: hwprobe: Document thead vendor extensions and xtheadvector extension
selftests: riscv: Fix vector tests
selftests: riscv: Support xtheadvector in vector tests
riscv: Add ghostwrite vulnerability
Heiko Stuebner (1):
RISC-V: define the elements of the VCSR vector CSR
Documentation/arch/riscv/hwprobe.rst | 10 +
Documentation/devicetree/bindings/riscv/cpus.yaml | 19 ++
.../devicetree/bindings/riscv/extensions.yaml | 10 +
arch/riscv/Kconfig.errata | 11 +
arch/riscv/Kconfig.vendor | 26 ++
arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi | 3 +-
arch/riscv/errata/thead/errata.c | 28 ++
arch/riscv/include/asm/bugs.h | 22 ++
arch/riscv/include/asm/cpufeature.h | 2 +
arch/riscv/include/asm/csr.h | 15 +
arch/riscv/include/asm/errata_list.h | 3 +-
arch/riscv/include/asm/hwprobe.h | 3 +-
arch/riscv/include/asm/switch_to.h | 2 +-
arch/riscv/include/asm/vector.h | 225 +++++++++++----
arch/riscv/include/asm/vendor_extensions/thead.h | 48 ++++
.../include/asm/vendor_extensions/thead_hwprobe.h | 19 ++
.../include/asm/vendor_extensions/vendor_hwprobe.h | 37 +++
arch/riscv/include/uapi/asm/hwprobe.h | 3 +-
arch/riscv/include/uapi/asm/vendor/thead.h | 3 +
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/bugs.c | 55 ++++
arch/riscv/kernel/cpufeature.c | 58 +++-
arch/riscv/kernel/kernel_mode_vector.c | 8 +-
arch/riscv/kernel/process.c | 4 +-
arch/riscv/kernel/signal.c | 6 +-
arch/riscv/kernel/sys_hwprobe.c | 5 +
arch/riscv/kernel/vector.c | 24 +-
arch/riscv/kernel/vendor_extensions.c | 10 +
arch/riscv/kernel/vendor_extensions/Makefile | 2 +
arch/riscv/kernel/vendor_extensions/thead.c | 29 ++
.../riscv/kernel/vendor_extensions/thead_hwprobe.c | 19 ++
drivers/base/cpu.c | 3 +
include/linux/cpu.h | 1 +
tools/testing/selftests/riscv/vector/.gitignore | 3 +-
tools/testing/selftests/riscv/vector/Makefile | 17 +-
.../selftests/riscv/vector/v_exec_initval_nolibc.c | 94 +++++++
tools/testing/selftests/riscv/vector/v_helpers.c | 68 +++++
tools/testing/selftests/riscv/vector/v_helpers.h | 8 +
tools/testing/selftests/riscv/vector/v_initval.c | 22 ++
.../selftests/riscv/vector/v_initval_nolibc.c | 68 -----
.../selftests/riscv/vector/vstate_exec_nolibc.c | 20 +-
.../testing/selftests/riscv/vector/vstate_prctl.c | 305 +++++++++++++--------
42 files changed, 1048 insertions(+), 272 deletions(-)
---
base-commit: 0e3f3649d44bf1b388a7613ade14c29cbdedf075
change-id: 20240530-xtheadvector-833d3d17b423
--
- Charlie
To be able to switch VMware products running on Linux to KVM some minor
changes are required to let KVM run/resume unmodified VMware guests.
First allow enabling of the VMware backdoor via an api. Currently the
setting of the VMware backdoor is limited to kernel boot parameters,
which forces all VM's running on a host to either run with or without
the VMware backdoor. Add a simple cap to allow enabling of the VMware
backdoor on a per VM basis. The default for that setting remains the
kvm.enable_vmware_backdoor boot parameter (which is false by default)
and can be changed on a per-vm basis via the KVM_CAP_X86_VMWARE_BACKDOOR
cap.
Second add a cap to forward hypercalls to userspace. I know that in
general that's frowned upon but VMwre guests send quite a few hypercalls
from userspace and it would be both impractical and largelly impossible
to handle all in the kernel. The change is trivial and I'd be maintaining
this code so I hope it's not a big deal.
The third commit just adds a self-test for the "forward VMware hypercalls
to userspace" functionality.
Cc: Doug Covelli <doug.covelli(a)broadcom.com>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Jonathan Corbet <corbet(a)lwn.net>
Cc: Sean Christopherson <seanjc(a)google.com>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Ingo Molnar <mingo(a)redhat.com>
Cc: Borislav Petkov <bp(a)alien8.de>
Cc: Dave Hansen <dave.hansen(a)linux.intel.com>
Cc: x86(a)kernel.org
Cc: "H. Peter Anvin" <hpa(a)zytor.com>
Cc: Shuah Khan <shuah(a)kernel.org>
Cc: Namhyung Kim <namhyung(a)kernel.org>
Cc: Arnaldo Carvalho de Melo <acme(a)redhat.com>
Cc: Isaku Yamahata <isaku.yamahata(a)intel.com>
Cc: Joel Stanley <joel(a)jms.id.au>
Cc: Zack Rusin <zack.rusin(a)broadcom.com>
Cc: kvm(a)vger.kernel.org
Cc: linux-doc(a)vger.kernel.org
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-kselftest(a)vger.kernel.org
Zack Rusin (3):
KVM: x86: Allow enabling of the vmware backdoor via a cap
KVM: x86: Add support for VMware guest specific hypercalls
KVM: selftests: x86: Add a test for KVM_CAP_X86_VMWARE_HYPERCALL
Documentation/virt/kvm/api.rst | 56 ++++++++-
arch/x86/include/asm/kvm_host.h | 2 +
arch/x86/kvm/emulate.c | 5 +-
arch/x86/kvm/svm/svm.c | 6 +-
arch/x86/kvm/vmx/vmx.c | 4 +-
arch/x86/kvm/x86.c | 47 ++++++++
arch/x86/kvm/x86.h | 7 +-
include/uapi/linux/kvm.h | 2 +
tools/include/uapi/linux/kvm.h | 2 +
tools/testing/selftests/kvm/Makefile | 1 +
.../kvm/x86_64/vmware_hypercall_test.c | 108 ++++++++++++++++++
11 files changed, 227 insertions(+), 13 deletions(-)
create mode 100644 tools/testing/selftests/kvm/x86_64/vmware_hypercall_test.c
--
2.43.0