On Tue, Feb 05, 2019 at 12:05:35PM +0000, Alexandru Elisei wrote:
> On 2/4/19 2:39 PM, Andrew Jones wrote:
> > On Mon, Feb 04, 2019 at 01:44:07PM +0000, Alexandru Elisei wrote:
> >> kvm-unit-tests is designed to be run with QEMU as the virtual machine
> >> monitor. It relies on devices emulated by QEMU (like isa-debug-exit or
> >> testdev) and it makes certain assumptions based on the implicit QEMU
> >> virtual environment configuration (like the serial base address).
> >>
> >> kvmtool [1] is a lightweight virtual machine monitor for running KVM
> >> guests. kvmtool has reduced complexity compared to QEMU and is easily
> >> hackable.
> >>
> >> This patch series aims to make it possible to run kvm-unit-tests using
> >> kvmtool on the arm and arm64 architectures, with two caveats:
> >>
> >> (1) When terminating a test, the userspace process won't exit with an exit
> >> code that signals the success or failure of the test. Output from the test
> >> can still be parsed to determine the outcome of the test.
> >>
> >> (2) kvmtool has been designed to work with a linux guest and it
> >> automatically generates the command line arguments for a Linux kernel. The
> >> arm/arm64 selftest and gic tests will fail if unexpected command line
> >> arguments are found. To get around this limitation, the test binary needs
> >> to be loaded using the --firmware option introduced by kvmtool in commit
> >> 5e4b563d75b9 ("arm: Allow command line for firmware"). This option
> >> suppresses the automatic kernel command line and can be used to run all
> >> tests, not just the tests that require specific arguments.
> >>
> >> The run scripts haven't been modified. To run a test under kvmtool, one
> >> needs to launch kvmtool manually. For example, to run the timer test the
> >> following command can be used:
> >>
> >> lkvm run --cpus 1 --console serial --firmware timer.flat.
> >>
> >> To run the gicv3-ipi test:
> >>
> >> lkvm run --cpus 8 --console serial --params "ipi" --irqchip gicv3 \
> >> --firmware gic.flat
> > This looks good to me. I tested with lkvm and saw that all tests were able
> > to run and pass, except pci-test since lkvm doesn't have pci-testdev. The
> > only other issue was selftest.vectors-user which ends in user mode and
> > thus can't make the PSCI call to exit. The following patch can get that
> > to work if lkvm users want it
> >
> > diff --git a/arm/selftest.c b/arm/selftest.c
> > index ea5101ef7217..7ba3f02a9b9d 100644
> > --- a/arm/selftest.c
> > +++ b/arm/selftest.c
> > @@ -272,10 +272,18 @@ static bool check_svc(void)
> > }
> > #endif
> >
> > +static void user_psci_off(struct pt_regs *regs, unsigned int esr)
> > +{
> > + psci_system_off();
> I was wondering if it's worth checking that the cause for the unknown exception
> was actually the instruction hvc #0 from user space. Getting the function id
> from x0/r0 is trivial, and we could also check the opcode from the memory
> location pointed to by the pc.
> > + halt();
> > +}
> > +
> > static void check_vectors(void *arg __unused)
> > {
> > report("und", check_und());
> > report("svc", check_svc());
> > + if (is_user())
> > + install_exception_handler(EL0_SYNC_64, ESR_EL1_EC_UNKNOWN, user_psci_off);
> > exit(report_summary());
> > }
>
> Thank you for posting this, when I started playing with kvm-unit-tests I noticed
> that selftest-vectors-user isn't working, but I totally forgot about it. I am
> interested in the patch, do you want to write the patch yourself? If not, I can
> pick it up and submit it.
I'll post it as 6/5 of this series. Have you reviewed/tested it? I.e. any
tags you'd like me to add to the posting?
Thanks,
drew
>
> >
> >
> > Anyway, thanks for submitting these patches to enable another user of
> > kvm-unit-tests.
> >
> > drew
> >
> >
> >> Changes in v3:
> >> * Updated cover letter with information about the kvmtool --firmware
> >> option.
> >> * Gathered Reviewed-by tags.
> >> * Renamed the config.h define UART_EARLY_BASE to CONFIG_UART_EARLY_BASE and
> >> made the necessary casts in lib/arm/io.c
> >>
> >> Changes in v2:
> >> * Generate lib/config.h when configuring kvm-unit-tests; arm/arm64 uses it
> >> to get the UART address.
> >> * Added --vmm configure option for arm/arm64 which will set the UART
> >> address in lib/config.h when the tests are run under QEMU or kvmtool.
> >> * Renamed psci_sys_reset() to psci_system_reset().
> >> * Dropped patches that allowed a test to ignore unexpected command line
> >> arguments.
> >>
> >> Summary:
> >> * Patches 1, 2 and 3 add support for configuring kvm-unit-tests on arm and
> >> arm64 to use the ns16550a UART emulated by kvmtool.
> >> * Patches 4 and 5 provide an alternative mechanism for terminating the
> >> virtual machine by using PSCI.
> >>
> >> [1] https://git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/
> >> [2] https://www.spinics.net/lists/kvm-arm/msg34352.html
> >>
> >> Alexandru Elisei (5):
> >> lib: arm: Use UART address from generated config.h
> >> configure: arm/arm64: Add --vmm option with no effect
> >> lib: arm: Use ns16550a UART when --vmm=kvmtool
> >> lib: arm: Implement PSCI SYSTEM_OFF in psci_system_off()
> >> lib: arm: Fallback to psci_system_off() in exit()
> >>
> >> configure | 32 ++++++++++++++++++++++++++++++++
> >> Makefile | 2 +-
> >> lib/arm/asm/psci.h | 3 ++-
> >> lib/arm/io.c | 41 ++++++++++++++++++++++++++---------------
> >> lib/arm/psci.c | 8 +++++++-
> >> .gitignore | 1 +
> >> 6 files changed, 69 insertions(+), 18 deletions(-)
> >>
> >> --
> >> 2.17.0
> >>
