| Message ID | 20220810125625.45295-5-imbrenda@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: s390: pv: implement lazy destroy for reboot | expand |
On 8/10/22 14:56, Claudio Imbrenda wrote: > If the appropriate UV feature bit is set, there is no need to perform > an export before import. > > Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com> > Reviewed-by: Nico Boehr <nrb@linux.ibm.com> > --- > arch/s390/kernel/uv.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c > index f9810d2a267c..b455646c8d74 100644 > --- a/arch/s390/kernel/uv.c > +++ b/arch/s390/kernel/uv.c > @@ -255,6 +255,8 @@ static int make_secure_pte(pte_t *ptep, unsigned long addr, > */ > static bool should_export_before_import(struct uv_cb_header *uvcb, struct mm_struct *mm) > { The misc feature indicates that the UV will automatically transfer ownership from one protected VM to another when importing a shared page. Other than that: Reviewed-by: Janosch Frank <frankja@linux.ibm.com> > + if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications)) > + return false; > if (uvcb->cmd == UVC_CMD_UNPIN_PAGE_SHARED) > return false; > return atomic_read(&mm->context.protected_count) > 1;
diff --git a/arch/s390/kernel/uv.c b/arch/s390/kernel/uv.c index f9810d2a267c..b455646c8d74 100644 --- a/arch/s390/kernel/uv.c +++ b/arch/s390/kernel/uv.c @@ -255,6 +255,8 @@ static int make_secure_pte(pte_t *ptep, unsigned long addr, */ static bool should_export_before_import(struct uv_cb_header *uvcb, struct mm_struct *mm) { + if (test_bit_inv(BIT_UV_FEAT_MISC, &uv_info.uv_feature_indications)) + return false; if (uvcb->cmd == UVC_CMD_UNPIN_PAGE_SHARED) return false; return atomic_read(&mm->context.protected_count) > 1;