target/i386: only include bits in pg_mode if they are not ignored

LA57/PKE/PKS is only relevant in 64-bit mode, and NXE is only relevant if
PAE is in use.  Since there is code that checks PG_MODE_LA57 to determine
the canonicality of addresses, make sure that the bit is not set by
mistake in 32-bit mode.  While it would not be a problem because 32-bit
addresses by definition fit in both 48-bit and 57-bit address spaces,
it is nicer if get_pg_mode() actually returns whether a feature is enabled,
and it allows a few simplifications in the page table walker.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2022-02-25 15:42:06 +01:00
parent def4c5570c
commit 991ec97625
1 changed files with 17 additions and 17 deletions

View File

@ -25,32 +25,35 @@
int get_pg_mode(CPUX86State *env)
{
int pg_mode = 0;
if (!(env->cr[0] & CR0_PG_MASK)) {
return 0;
}
if (env->cr[0] & CR0_WP_MASK) {
pg_mode |= PG_MODE_WP;
}
if (env->cr[4] & CR4_PAE_MASK) {
pg_mode |= PG_MODE_PAE;
if (env->efer & MSR_EFER_NXE) {
pg_mode |= PG_MODE_NXE;
}
}
if (env->cr[4] & CR4_PSE_MASK) {
pg_mode |= PG_MODE_PSE;
}
if (env->cr[4] & CR4_PKE_MASK) {
pg_mode |= PG_MODE_PKE;
}
if (env->cr[4] & CR4_PKS_MASK) {
pg_mode |= PG_MODE_PKS;
}
if (env->cr[4] & CR4_SMEP_MASK) {
pg_mode |= PG_MODE_SMEP;
}
if (env->cr[4] & CR4_LA57_MASK) {
pg_mode |= PG_MODE_LA57;
}
if (env->hflags & HF_LMA_MASK) {
pg_mode |= PG_MODE_LMA;
}
if (env->efer & MSR_EFER_NXE) {
pg_mode |= PG_MODE_NXE;
if (env->cr[4] & CR4_PKE_MASK) {
pg_mode |= PG_MODE_PKE;
}
if (env->cr[4] & CR4_PKS_MASK) {
pg_mode |= PG_MODE_PKS;
}
if (env->cr[4] & CR4_LA57_MASK) {
pg_mode |= PG_MODE_LA57;
}
}
return pg_mode;
}
@ -279,9 +282,7 @@ do_check_protect_pse36:
*prot |= PAGE_EXEC;
}
if (!(pg_mode & PG_MODE_LMA)) {
pkr = 0;
} else if (ptep & PG_USER_MASK) {
if (ptep & PG_USER_MASK) {
pkr = pg_mode & PG_MODE_PKE ? env->pkru : 0;
} else {
pkr = pg_mode & PG_MODE_PKS ? env->pkrs : 0;
@ -344,8 +345,7 @@ do_check_protect_pse36:
if (is_user)
error_code |= PG_ERROR_U_MASK;
if (is_write1 == 2 &&
(((pg_mode & PG_MODE_NXE) && (pg_mode & PG_MODE_PAE)) ||
(pg_mode & PG_MODE_SMEP)))
((pg_mode & PG_MODE_NXE) || (pg_mode & PG_MODE_SMEP)))
error_code |= PG_ERROR_I_D_MASK;
return error_code;
}