On Wed, 13 Jan 2021 23:08:08 +0200 Jarkko Sakkinen wrote:
> On Wed, Jan 13, 2021 at 02:09:17PM +1300, Kai Huang wrote:
> > On Wed, 13 Jan 2021 01:33:51 +0200 jarkko@xxxxxxxxxx wrote:
> > > From: "jarkko@xxxxxxxxxx" <jarkko@xxxxxxxxxx>
> > >
> > > Encapsulate the snippet in sgx_free_epc_page() concerning EREMOVE to
> > > sgx_reset_epc_page(), which is a static helper function for
> > > sgx_encl_release(). It's the only function existing, which deals with
> > > initialized pages.
> > >
> > > Signed-off-by: jarkko@xxxxxxxxxx <jarkko@xxxxxxxxxx>
> > > ---
> > > v2: Fixed a compilation error s/page/epc_page/ change not amended
> > > to the patches.
> > > arch/x86/kernel/cpu/sgx/encl.c | 15 ++++++++++++++-
> > > arch/x86/kernel/cpu/sgx/main.c | 10 ++++------
> > > 2 files changed, 18 insertions(+), 7 deletions(-)
> > >
> > > diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
> > > index fe7256db6e73..511f4bc70699 100644
> > > --- a/arch/x86/kernel/cpu/sgx/encl.c
> > > +++ b/arch/x86/kernel/cpu/sgx/encl.c
> > > @@ -389,6 +389,16 @@ const struct vm_operations_struct sgx_vm_ops = {
> > > .access = sgx_vma_access,
> > > };
> > >
> > > +
> > > +static void sgx_reset_epc_page(struct sgx_epc_page *epc_page)
> > > +{
> > > + int ret;
> > > +
> > > + ret = __eremove(sgx_get_epc_virt_addr(epc_page));
> > > + if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret))
> > > + return;
> > > +}
> > > +
> > > /**
> > > * sgx_encl_release - Destroy an enclave instance
> > > * @kref: address of a kref inside &sgx_encl
> > > @@ -412,6 +422,7 @@ void sgx_encl_release(struct kref *ref)
> > > if (sgx_unmark_page_reclaimable(entry->epc_page))
> > > continue;
> > >
> > > + sgx_reset_epc_page(entry->epc_page);
> > > sgx_free_epc_page(entry->epc_page);
> > > encl->secs_child_cnt--;
> > > entry->epc_page = NULL;
> > > @@ -423,6 +434,7 @@ void sgx_encl_release(struct kref *ref)
> > > xa_destroy(&encl->page_array);
> > >
> > > if (!encl->secs_child_cnt && encl->secs.epc_page) {
> > > + sgx_reset_epc_page(encl->secs.epc_page);
> > > sgx_free_epc_page(encl->secs.epc_page);
> > > encl->secs.epc_page = NULL;
> > > }
> > > @@ -431,7 +443,8 @@ void sgx_encl_release(struct kref *ref)
> > > va_page = list_first_entry(&encl->va_pages, struct sgx_va_page,
> > > list);
> > > list_del(&va_page->list);
> > > - sgx_free_epc_page(va_page->epc_page);
> > > + sgx_reset_epc_page(entry->epc_page);
> > > + sgx_free_epc_page(entry->epc_page);
> >
> > Reply so that Sean can see, since he just subscribed to linux-sgx list.
> >
> > As Sean pointed out in KVM SGX virtualization thread, entry should be va_page.
>
> Thank, noticed, and responded. I'm sending v3. I think it would be best to
> then include that version to KVM patch set, as there is no such a rush to
> get my patches to upstream. I already dropped them from my bleeding edge
> numa branch.
Sure. I'll take your patch once I see it. Thanks Jarkko.
