mirror of
https://github.com/torvalds/linux.git
synced 2026-05-26 16:12:59 +02:00
6ec982b5a2
Use u8 instead of uint8_t to make the KVM selftests code more concise and more similar to the kernel (since selftests are primarily developed by kernel developers). This commit was generated with the following command: git ls-files tools/testing/selftests/kvm | xargs sed -i 's/uint8_t/u8/g' Then by manually adjusting whitespace to make checkpatch.pl happy. No functional change intended. Signed-off-by: David Matlack <dmatlack@google.com> Link: https://patch.msgid.link/20260420212004.3938325-11-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com>
112 lines
2.8 KiB
C
112 lines
2.8 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Test shared zeropage handling (with/without storage keys)
|
|
*
|
|
* Copyright (C) 2024, Red Hat, Inc.
|
|
*/
|
|
#include <sys/mman.h>
|
|
|
|
#include <linux/fs.h>
|
|
|
|
#include "test_util.h"
|
|
#include "kvm_util.h"
|
|
#include "kselftest.h"
|
|
#include "ucall_common.h"
|
|
|
|
static void set_storage_key(void *addr, u8 skey)
|
|
{
|
|
asm volatile("sske %0,%1" : : "d" (skey), "a" (addr));
|
|
}
|
|
|
|
static void guest_code(void)
|
|
{
|
|
/* Issue some storage key instruction. */
|
|
set_storage_key((void *)0, 0x98);
|
|
GUEST_DONE();
|
|
}
|
|
|
|
/*
|
|
* Returns 1 if the shared zeropage is mapped, 0 if something else is mapped.
|
|
* Returns < 0 on error or if nothing is mapped.
|
|
*/
|
|
static int maps_shared_zeropage(int pagemap_fd, void *addr)
|
|
{
|
|
struct page_region region;
|
|
struct pm_scan_arg arg = {
|
|
.start = (uintptr_t)addr,
|
|
.end = (uintptr_t)addr + 4096,
|
|
.vec = (uintptr_t)®ion,
|
|
.vec_len = 1,
|
|
.size = sizeof(struct pm_scan_arg),
|
|
.category_mask = PAGE_IS_PFNZERO,
|
|
.category_anyof_mask = PAGE_IS_PRESENT,
|
|
.return_mask = PAGE_IS_PFNZERO,
|
|
};
|
|
return ioctl(pagemap_fd, PAGEMAP_SCAN, &arg);
|
|
}
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
char *mem, *page0, *page1, *page2, tmp;
|
|
const size_t pagesize = getpagesize();
|
|
struct kvm_vcpu *vcpu;
|
|
struct kvm_vm *vm;
|
|
struct ucall uc;
|
|
int pagemap_fd;
|
|
|
|
ksft_print_header();
|
|
ksft_set_plan(3);
|
|
|
|
/*
|
|
* We'll use memory that is not mapped into the VM for simplicity.
|
|
* Shared zeropages are enabled/disabled per-process.
|
|
*/
|
|
mem = mmap(0, 3 * pagesize, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0);
|
|
TEST_ASSERT(mem != MAP_FAILED, "mmap() failed");
|
|
|
|
/* Disable THP. Ignore errors on older kernels. */
|
|
madvise(mem, 3 * pagesize, MADV_NOHUGEPAGE);
|
|
|
|
page0 = mem;
|
|
page1 = page0 + pagesize;
|
|
page2 = page1 + pagesize;
|
|
|
|
/* Can we even detect shared zeropages? */
|
|
pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
|
|
TEST_REQUIRE(pagemap_fd >= 0);
|
|
|
|
tmp = *page0;
|
|
asm volatile("" : "+r" (tmp));
|
|
TEST_REQUIRE(maps_shared_zeropage(pagemap_fd, page0) == 1);
|
|
|
|
vm = vm_create_with_one_vcpu(&vcpu, guest_code);
|
|
|
|
/* Verify that we get the shared zeropage after VM creation. */
|
|
tmp = *page1;
|
|
asm volatile("" : "+r" (tmp));
|
|
ksft_test_result(maps_shared_zeropage(pagemap_fd, page1) == 1,
|
|
"Shared zeropages should be enabled\n");
|
|
|
|
/*
|
|
* Let our VM execute a storage key instruction that should
|
|
* unshare all shared zeropages.
|
|
*/
|
|
vcpu_run(vcpu);
|
|
get_ucall(vcpu, &uc);
|
|
TEST_ASSERT_EQ(uc.cmd, UCALL_DONE);
|
|
|
|
/* Verify that we don't have a shared zeropage anymore. */
|
|
ksft_test_result(!maps_shared_zeropage(pagemap_fd, page1),
|
|
"Shared zeropage should be gone\n");
|
|
|
|
/* Verify that we don't get any new shared zeropages. */
|
|
tmp = *page2;
|
|
asm volatile("" : "+r" (tmp));
|
|
ksft_test_result(!maps_shared_zeropage(pagemap_fd, page2),
|
|
"Shared zeropages should be disabled\n");
|
|
|
|
kvm_vm_free(vm);
|
|
|
|
ksft_finished();
|
|
}
|