Ping, any chance of a review?
I'm happy to rework this or merge it with existing tests if required.
On Wednesday, 2020-11-18 at 12:11:29 GMT, David Edmondson wrote:
> Verify that the clflushopt instruction succeeds when applied to an
> MMIO address at both cpl0 and cpl3.
>
> Suggested-by: Joao Martins <joao.m.martins@xxxxxxxxxx>
> Signed-off-by: David Edmondson <david.edmondson@xxxxxxxxxx>
> ---
> x86/Makefile.common | 3 ++-
> x86/clflushopt_mmio.c | 45 +++++++++++++++++++++++++++++++++++++++++++
> x86/unittests.cfg | 5 +++++
> 3 files changed, 52 insertions(+), 1 deletion(-)
> create mode 100644 x86/clflushopt_mmio.c
>
> diff --git a/x86/Makefile.common b/x86/Makefile.common
> index b942086..e11666a 100644
> --- a/x86/Makefile.common
> +++ b/x86/Makefile.common
> @@ -62,7 +62,8 @@ tests-common = $(TEST_DIR)/vmexit.flat $(TEST_DIR)/tsc.flat \
> $(TEST_DIR)/init.flat $(TEST_DIR)/smap.flat \
> $(TEST_DIR)/hyperv_synic.flat $(TEST_DIR)/hyperv_stimer.flat \
> $(TEST_DIR)/hyperv_connections.flat \
> - $(TEST_DIR)/umip.flat $(TEST_DIR)/tsx-ctrl.flat
> + $(TEST_DIR)/umip.flat $(TEST_DIR)/tsx-ctrl.flat \
> + $(TEST_DIR)/clflushopt_mmio.flat
>
> test_cases: $(tests-common) $(tests)
>
> diff --git a/x86/clflushopt_mmio.c b/x86/clflushopt_mmio.c
> new file mode 100644
> index 0000000..f048f58
> --- /dev/null
> +++ b/x86/clflushopt_mmio.c
> @@ -0,0 +1,45 @@
> +#include "libcflat.h"
> +#include "usermode.h"
> +#include "pci.h"
> +#include "x86/asm/pci.h"
> +
> +static volatile int ud;
> +static void *memaddr = (void *)0xfed00000; /* HPET */
> +
> +static void handle_ud(struct ex_regs *regs)
> +{
> + ud = 1;
> + regs->rip += 4;
> +}
> +
> +static void try_clflushopt(const char *comment)
> +{
> + int expected = !this_cpu_has(X86_FEATURE_CLFLUSHOPT);
> +
> + ud = 0;
> + /* clflushopt (%rbx): */
> + asm volatile(".byte 0x66, 0x0f, 0xae, 0x3b" : : "b" (memaddr));
> +
> + report(ud == expected, comment, expected ? "ABSENT" : "present");
> +}
> +
> +static uint64_t user_clflushopt(void)
> +{
> + try_clflushopt("clflushopt-mmio@cpl3 (%s)");
> +
> + return 0;
> +}
> +
> +int main(int ac, char **av)
> +{
> + bool raised;
> +
> + setup_vm();
> +
> + handle_exception(UD_VECTOR, handle_ud);
> +
> + (void) run_in_user(user_clflushopt, false, 0, 0, 0, 0, &raised);
> + try_clflushopt("clflushopt-mmio@cpl0 (%s)");
> +
> + return report_summary();
> +}
> diff --git a/x86/unittests.cfg b/x86/unittests.cfg
> index 872d679..35bedf8 100644
> --- a/x86/unittests.cfg
> +++ b/x86/unittests.cfg
> @@ -359,3 +359,8 @@ extra_params = -M q35,kernel-irqchip=split -device intel-iommu,intremap=on,eim=o
> file = tsx-ctrl.flat
> extra_params = -cpu host
> groups = tsx-ctrl
> +
> +[clflushopt_mmio]
> +file = clflushopt_mmio.flat
> +extra_params = -cpu host
> +arch = x86_64
> --
> 2.29.2
dme.
--
It's alright, we told you what to dream.
