Change two functions (test_mmx_movq_mf and test_movabs) using
unified trap_emulator.
Signed-off-by: Arthur Chunqi Li <yzt356@xxxxxxxxx>
---
x86/emulator.c | 70 ++++++++++++--------------------------------------------
1 file changed, 15 insertions(+), 55 deletions(-)
diff --git a/x86/emulator.c b/x86/emulator.c
index b3626fa..16d63e0 100644
--- a/x86/emulator.c
+++ b/x86/emulator.c
@@ -772,38 +772,19 @@ static void advance_rip_by_3_and_note_exception(struct ex_regs *regs)
static void test_mmx_movq_mf(uint64_t *mem, uint8_t *insn_page,
uint8_t *alt_insn_page, void *insn_ram)
{
- uint16_t fcw = 0; // all exceptions unmasked
- ulong *cr3 = (ulong *)read_cr3();
-
- write_cr0(read_cr0() & ~6); // TS, EM
- // Place a trapping instruction in the page to trigger a VMEXIT
- insn_page[0] = 0x89; // mov %eax, (%rax)
- insn_page[1] = 0x00;
- insn_page[2] = 0x90; // nop
- insn_page[3] = 0xc3; // ret
- // Place the instruction we want the hypervisor to see in the alternate page
- alt_insn_page[0] = 0x0f; // movq %mm0, (%rax)
- alt_insn_page[1] = 0x7f;
- alt_insn_page[2] = 0x00;
- alt_insn_page[3] = 0xc3; // ret
+ uint16_t fcw = 0; /* all exceptions unmasked */
+ u8 alt_insn[] = {0x0f, 0x7f, 0x00}; /* movq %mm0, (%rax) */
+ void *stack = alloc_page();
+ write_cr0(read_cr0() & ~6); /* TS, EM */
exceptions = 0;
handle_exception(MF_VECTOR, advance_rip_by_3_and_note_exception);
-
- // Load the code TLB with insn_page, but point the page tables at
- // alt_insn_page (and keep the data TLB clear, for AMD decode assist).
- // This will make the CPU trap on the insn_page instruction but the
- // hypervisor will see alt_insn_page.
- install_page(cr3, virt_to_phys(insn_page), insn_ram);
asm volatile("fninit; fldcw %0" : : "m"(fcw));
- asm volatile("fldz; fldz; fdivp"); // generate exception
- invlpg(insn_ram);
- // Load code TLB
- asm volatile("call *%0" : : "r"(insn_ram + 3));
- install_page(cr3, virt_to_phys(alt_insn_page), insn_ram);
- // Trap, let hypervisor emulate at alt_insn_page
- asm volatile("call *%0" : : "r"(insn_ram), "a"(mem));
- // exit MMX mode
+ asm volatile("fldz; fldz; fdivp"); /* generate exception */
+
+ inregs = (struct regs){ .rsp=(u64)stack+1024 };
+ trap_emulator(mem, alt_insn, 3);
+ /* exit MMX mode */
asm volatile("fnclex; emms");
report("movq mmx generates #MF", exceptions == 1);
handle_exception(MF_VECTOR, 0);
@@ -812,33 +793,12 @@ static void test_mmx_movq_mf(uint64_t *mem, uint8_t *insn_page,
static void test_movabs(uint64_t *mem, uint8_t *insn_page,
uint8_t *alt_insn_page, void *insn_ram)
{
- uint64_t val = 0;
- ulong *cr3 = (ulong *)read_cr3();
-
- // Pad with RET instructions
- memset(insn_page, 0xc3, 4096);
- memset(alt_insn_page, 0xc3, 4096);
- // Place a trapping instruction in the page to trigger a VMEXIT
- insn_page[0] = 0x89; // mov %eax, (%rax)
- insn_page[1] = 0x00;
- // Place the instruction we want the hypervisor to see in the alternate
- // page. A buggy hypervisor will fetch a 32-bit immediate and return
- // 0xffffffffc3c3c3c3.
- alt_insn_page[0] = 0x48; // mov $0xc3c3c3c3c3c3c3c3, %rcx
- alt_insn_page[1] = 0xb9;
-
- // Load the code TLB with insn_page, but point the page tables at
- // alt_insn_page (and keep the data TLB clear, for AMD decode assist).
- // This will make the CPU trap on the insn_page instruction but the
- // hypervisor will see alt_insn_page.
- install_page(cr3, virt_to_phys(insn_page), insn_ram);
- // Load code TLB
- invlpg(insn_ram);
- asm volatile("call *%0" : : "r"(insn_ram + 3));
- // Trap, let hypervisor emulate at alt_insn_page
- install_page(cr3, virt_to_phys(alt_insn_page), insn_ram);
- asm volatile("call *%1" : "=c"(val) : "r"(insn_ram), "a"(mem), "c"(0));
- report("64-bit mov imm", val == 0xc3c3c3c3c3c3c3c3);
+ /* mov $0x9090909090909090, %rcx */
+ uint8_t alt_insn[] = {0x48, 0xb9, 0x90, 0x90, 0x90,
+ 0x90, 0x90, 0x90, 0x90, 0x90};
+ inregs = (struct regs){ 0 };
+ trap_emulator(mem, alt_insn, 10);
+ report("64-bit mov imm2", outregs.rcx == 0x9090909090909090);
}
static void test_crosspage_mmio(volatile uint8_t *mem)
--
1.7.9.5
--
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