> +static void svm_l2_nm_test(struct svm_test *svm)
> +{
> + write_cr0(read_cr0() | X86_CR0_TS);
> + asm volatile("fnop");
> +}
> +
> +static void svm_l2_of_test(struct svm_test *svm)
> +{
> + struct far_pointer32 fp = {
> + .offset = (uintptr_t)&&into,
> + .selector = KERNEL_CS32,
> + };
> + uintptr_t rsp;
> +
> + asm volatile ("mov %%rsp, %0" : "=r"(rsp));
> +
> + if (fp.offset != (uintptr_t)&&into) {
> + printf("Codee address too high.\n");
Nit: Code
> + return;
> + }
> +
> + if ((u32)rsp != rsp) {
> + printf("Stack address too high.\n");
> + }
> +
> + asm goto("lcall *%0" : : "m" (fp) : "rax" : into);
> + return;
> +into:
> + asm volatile (".code32;"
> + "movl $0x7fffffff, %eax;"
> + "addl %eax, %eax;"
> + "into;"
> + "lret;"
> + ".code64");
> + __builtin_unreachable();
> +}
> +
> +static void svm_l2_ac_test(struct svm_test *test)
> +{
> + bool hit_ac = false;
> +
> + write_cr0(read_cr0() | X86_CR0_AM);
> + write_rflags(read_rflags() | X86_EFLAGS_AC);
> +
> + run_in_user(usermode_callback, AC_VECTOR, 0, 0, 0, 0, &hit_ac);
> +
> + report(hit_ac, "Usermode #AC handled in L2");
> + vmmcall();
> +}
> +
> +static void svm_ac_init(void)
> +{
> + set_user_mask_all(phys_to_virt(read_cr3()), PAGE_LEVEL);
> +}
> +
> +static void svm_ac_uninit(void)
> +{
> + clear_user_mask_all(phys_to_virt(read_cr3()), PAGE_LEVEL);
> +}
> +
> +struct svm_exception_test {
> + u8 vector;
> + void (*guest_code)(struct svm_test*);
> + void (*init_test)(void);
> + void (*uninit_test)(void);
> +};
> +
> +struct svm_exception_test svm_exception_tests[] = {
> + { GP_VECTOR, svm_l2_gp_test },
> + { UD_VECTOR, svm_l2_ud_test },
> + { DE_VECTOR, svm_l2_de_test },
> + { BP_VECTOR, svm_l2_bp_test },
> + { NM_VECTOR, svm_l2_nm_test },
> + { OF_VECTOR, svm_l2_of_test },
> + { DB_VECTOR, svm_l2_db_test },
> + { AC_VECTOR, svm_l2_ac_test, svm_ac_init, svm_ac_uninit },
> +};
If you set and clear PT_USER_MASK in svm_l2_ac_test() before calling
into userspace you can remove init_test and uninit_test from the
framework all together. That will simplify the code.
Further, it would be nice to then hoist this framework and the one in
vmx into a common x86 file, but looking at this that may be something
to think about in the future. There would have to be wrappers when
interacting with the vmc{s,b} and macros at the very least.
> +
> +static u8 svm_exception_test_vector;
> +
> +static void svm_exception_handler(struct ex_regs *regs)
> +{
> + report(regs->vector == svm_exception_test_vector,
> + "Handling %s in L2's exception handler",
> + exception_mnemonic(svm_exception_test_vector));
> + vmmcall();
> +}
> +
