Use ISTs instead of tasks.
One big remaining difference between 32- and 64-bits is that tasks
on 32-bits take care of saving registers. ISTs do not, only the
stack is affected.
For now, just save/restore caller-save registers in the assembly
wrapper, since there's just one test that uses ISTs. Later we
can extend the existing APIs to register exception handlers, so
that they can use tasks or ISTs too.
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
x86/eventinj.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/x86/eventinj.c b/x86/eventinj.c
index 050bc8c..6547351 100644
--- a/x86/eventinj.c
+++ b/x86/eventinj.c
@@ -55,7 +55,6 @@ static void flush_idt_page()
static volatile unsigned int test_divider;
static volatile int test_count;
-#ifndef __x86_64__
ulong stack_phys;
void *stack_va;
@@ -69,15 +68,24 @@ void do_pf_tss(void)
extern void pf_tss(void);
-asm (
- "pf_tss: \n\t"
+asm ("pf_tss: \n\t"
+#ifdef __x86_64__
+ // no task on x86_64, save/restore caller-save regs
+ "push %rax; push %rcx; push %rdx; push %rsi; push %rdi\n"
+ "push %r8; push %r9; push %r10; push %r11\n"
+#endif
"call do_pf_tss \n\t"
- "add $"S", %"R "sp\n\t" // discard error code
+#ifdef __x86_64__
+ "pop %r11; pop %r10; pop %r9; pop %r8\n"
+ "pop %rdi; pop %rsi; pop %rdx; pop %rcx; pop %rax\n"
+#endif
+ "add $"S", %"R "sp\n\t" // discard error code
"iret"W" \n\t"
"jmp pf_tss\n\t"
);
+#ifndef __x86_64__
static void of_isr(struct ex_regs *r)
{
printf("OF isr running\n");
@@ -356,7 +364,6 @@ int main()
irq_disable();
printf("After NMI to self\n");
report("NMI", test_count == 2);
-#ifndef __x86_64__
stack_phys = (ulong)virt_to_phys(alloc_page());
stack_va = alloc_vpage();
@@ -395,7 +402,6 @@ int main()
restore_stack();
printf("After int33\n");
report("NP PF exceptions", test_count == 2);
-#endif
pt = alloc_page();
cr3 = (void*)read_cr3();
--
1.8.3.1
--
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