diff options
| -rw-r--r-- | target-i386/machine.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/target-i386/machine.c b/target-i386/machine.c index af4c167f84..f9ec581faa 100644 --- a/target-i386/machine.c +++ b/target-i386/machine.c @@ -252,6 +252,24 @@ static void cpu_pre_save(void *opaque) } env->fpregs_format_vmstate = 0; + + /* + * Real mode guest segments register DPL should be zero. + * Older KVM version were setting it wrongly. + * Fixing it will allow live migration to host with unrestricted guest + * support (otherwise the migration will fail with invalid guest state + * error). + */ + if (!(env->cr[0] & CR0_PE_MASK) && + (env->segs[R_CS].flags >> DESC_DPL_SHIFT & 3) != 0) { + env->segs[R_CS].flags &= ~(env->segs[R_CS].flags & DESC_DPL_MASK); + env->segs[R_DS].flags &= ~(env->segs[R_DS].flags & DESC_DPL_MASK); + env->segs[R_ES].flags &= ~(env->segs[R_ES].flags & DESC_DPL_MASK); + env->segs[R_FS].flags &= ~(env->segs[R_FS].flags & DESC_DPL_MASK); + env->segs[R_GS].flags &= ~(env->segs[R_GS].flags & DESC_DPL_MASK); + env->segs[R_SS].flags &= ~(env->segs[R_SS].flags & DESC_DPL_MASK); + } + } static int cpu_post_load(void *opaque, int version_id) |