target-i386: SVM: acknowledge interrupt only after it is taken

SVM specifies that the V_IRQ mask is only to be removed, if the
interrupt that is to be delivered actually is delivered.

As of the SVM rewrite, this mask is always unmasked when the main cpu
loop is processed, leaving a corner case where calling the interrupt
handler causes a #PF. In that case (booting Linux / starting gfxboot)
the current implementation tells the VMM the interrupt is taken, even
though it is not.

This patch modifies the VIRQ unmasking to occur after do_interrupt,
making gfxboot work again.

Signed-off-by: Alexander Graf <[email protected]>
Signed-off-by: Aurelien Jarno <[email protected]>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6008 c046a42c-6fe2-441c-8c8c-71466251a162

diff --git a/cpu-exec.c b/cpu-exec.c
index 65435f5415a3212177ca77d2d130a34978154a78..ed1545b5e15064d4f7124c28b75644d5ac20f11b 100644 (file)
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -401,11 +401,11 @@ int cpu_exec(CPUState *env1)
                             int intno;
                             /* FIXME: this should respect TPR */
                             svm_check_intercept(SVM_EXIT_VINTR);
-                            env->interrupt_request &= ~CPU_INTERRUPT_VIRQ;
                             intno = ldl_phys(env->vm_vmcb + offsetof(struct vmcb, control.int_vector));
                             if (loglevel & CPU_LOG_TB_IN_ASM)
                                 fprintf(logfile, "Servicing virtual hardware INT=0x%02x\n", intno);
                             do_interrupt(intno, 0, 0, 0, 1);
+                            env->interrupt_request &= ~CPU_INTERRUPT_VIRQ;
                             next_tb = 0;
 #endif
                         }