This is how the steps are ordered in the manual. EFLAGS.NT is
overwritten after the fact in the saved image.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
target/i386/tcg/seg_helper.c | 85 +++++++++++++++++++-----------------
1 file changed, 45 insertions(+), 40 deletions(-)
diff --git a/target/i386/tcg/seg_helper.c b/target/i386/tcg/seg_helper.c
index 77f2c65c3cf..7663e653e84 100644
--- a/target/i386/tcg/seg_helper.c
+++ b/target/i386/tcg/seg_helper.c
@@ -325,6 +325,42 @@ static int switch_tss_ra(CPUX86State *env, int
tss_selector,
access_prepare_mmu(&new, env, tss_base, tss_limit,
MMU_DATA_LOAD, cpu_mmu_index_kernel(env), retaddr);
+ /* save the current state in the old TSS */
+ old_eflags = cpu_compute_eflags(env);
+ if (old_type & 8) {
+ /* 32 bit */
+ access_stl(&old, env->tr.base + 0x20, next_eip);
+ access_stl(&old, env->tr.base + 0x24, old_eflags);
+ access_stl(&old, env->tr.base + (0x28 + 0 * 4), env->regs[R_EAX]);
+ access_stl(&old, env->tr.base + (0x28 + 1 * 4), env->regs[R_ECX]);
+ access_stl(&old, env->tr.base + (0x28 + 2 * 4), env->regs[R_EDX]);
+ access_stl(&old, env->tr.base + (0x28 + 3 * 4), env->regs[R_EBX]);
+ access_stl(&old, env->tr.base + (0x28 + 4 * 4), env->regs[R_ESP]);
+ access_stl(&old, env->tr.base + (0x28 + 5 * 4), env->regs[R_EBP]);
+ access_stl(&old, env->tr.base + (0x28 + 6 * 4), env->regs[R_ESI]);
+ access_stl(&old, env->tr.base + (0x28 + 7 * 4), env->regs[R_EDI]);
+ for (i = 0; i < 6; i++) {
+ access_stw(&old, env->tr.base + (0x48 + i * 4),
+ env->segs[i].selector);
+ }
+ } else {
+ /* 16 bit */
+ access_stw(&old, env->tr.base + 0x0e, next_eip);
+ access_stw(&old, env->tr.base + 0x10, old_eflags);
+ access_stw(&old, env->tr.base + (0x12 + 0 * 2), env->regs[R_EAX]);
+ access_stw(&old, env->tr.base + (0x12 + 1 * 2), env->regs[R_ECX]);
+ access_stw(&old, env->tr.base + (0x12 + 2 * 2), env->regs[R_EDX]);
+ access_stw(&old, env->tr.base + (0x12 + 3 * 2), env->regs[R_EBX]);
+ access_stw(&old, env->tr.base + (0x12 + 4 * 2), env->regs[R_ESP]);
+ access_stw(&old, env->tr.base + (0x12 + 5 * 2), env->regs[R_EBP]);
+ access_stw(&old, env->tr.base + (0x12 + 6 * 2), env->regs[R_ESI]);
+ access_stw(&old, env->tr.base + (0x12 + 7 * 2), env->regs[R_EDI]);
+ for (i = 0; i < 4; i++) {
+ access_stw(&old, env->tr.base + (0x22 + i * 2),
+ env->segs[i].selector);
+ }
+ }
+
/* read all the registers from the new TSS */
if (type & 8) {
/* 32 bit */
@@ -364,49 +400,16 @@ static int switch_tss_ra(CPUX86State *env, int
tss_selector,
if (source == SWITCH_TSS_JMP || source == SWITCH_TSS_IRET) {
tss_set_busy(env, env->tr.selector, 0, retaddr);
}
- old_eflags = cpu_compute_eflags(env);
+
if (source == SWITCH_TSS_IRET) {
old_eflags &= ~NT_MASK;
+ if (old_type & 8) {
+ access_stl(&old, env->tr.base + 0x24, old_eflags);
+ } else {
+ access_stw(&old, env->tr.base + 0x10, old_eflags);
+ }
}
- /* save the current state in the old TSS */
- if (old_type & 8) {
- /* 32 bit */
- access_stl(&old, env->tr.base + 0x20, next_eip);
- access_stl(&old, env->tr.base + 0x24, old_eflags);
- access_stl(&old, env->tr.base + (0x28 + 0 * 4), env->regs[R_EAX]);
- access_stl(&old, env->tr.base + (0x28 + 1 * 4), env->regs[R_ECX]);
- access_stl(&old, env->tr.base + (0x28 + 2 * 4), env->regs[R_EDX]);
- access_stl(&old, env->tr.base + (0x28 + 3 * 4), env->regs[R_EBX]);
- access_stl(&old, env->tr.base + (0x28 + 4 * 4), env->regs[R_ESP]);
- access_stl(&old, env->tr.base + (0x28 + 5 * 4), env->regs[R_EBP]);
- access_stl(&old, env->tr.base + (0x28 + 6 * 4), env->regs[R_ESI]);
- access_stl(&old, env->tr.base + (0x28 + 7 * 4), env->regs[R_EDI]);
- for (i = 0; i < 6; i++) {
- access_stw(&old, env->tr.base + (0x48 + i * 4),
- env->segs[i].selector);
- }
- } else {
- /* 16 bit */
- access_stw(&old, env->tr.base + 0x0e, next_eip);
- access_stw(&old, env->tr.base + 0x10, old_eflags);
- access_stw(&old, env->tr.base + (0x12 + 0 * 2), env->regs[R_EAX]);
- access_stw(&old, env->tr.base + (0x12 + 1 * 2), env->regs[R_ECX]);
- access_stw(&old, env->tr.base + (0x12 + 2 * 2), env->regs[R_EDX]);
- access_stw(&old, env->tr.base + (0x12 + 3 * 2), env->regs[R_EBX]);
- access_stw(&old, env->tr.base + (0x12 + 4 * 2), env->regs[R_ESP]);
- access_stw(&old, env->tr.base + (0x12 + 5 * 2), env->regs[R_EBP]);
- access_stw(&old, env->tr.base + (0x12 + 6 * 2), env->regs[R_ESI]);
- access_stw(&old, env->tr.base + (0x12 + 7 * 2), env->regs[R_EDI]);
- for (i = 0; i < 4; i++) {
- access_stw(&old, env->tr.base + (0x22 + i * 2),
- env->segs[i].selector);
- }
- }
-
- /* now if an exception occurs, it will occurs in the next task
- context */
-
if (source == SWITCH_TSS_CALL) {
cpu_stw_kernel_ra(env, tss_base, env->tr.selector, retaddr);
new_eflags |= NT_MASK;
@@ -418,7 +421,9 @@ static int switch_tss_ra(CPUX86State *env, int tss_selector,
}
/* set the new CPU state */
- /* from this point, any exception which occurs can give problems */
+
+ /* now if an exception occurs, it will occur in the next task context */
+
env->cr[0] |= CR0_TS_MASK;
env->hflags |= HF_TS_MASK;
env->tr.selector = tss_selector;
--
2.45.2
