* [PATCH v2 0/2] Take away EREMOVE from sgx_free_epc_page()
@ 2021-01-12 23:33 jarkko
2021-01-12 23:33 ` [PATCH v2 1/2] x86/sgx: Remove a warn " jarkko
2021-01-12 23:33 ` [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE " jarkko
0 siblings, 2 replies; 6+ messages in thread
From: jarkko @ 2021-01-12 23:33 UTC (permalink / raw)
To: linux-sgx; +Cc: dave.hansen, kai.huang, haitao.huang, jarkko
From: "jarkko@kernel.org" <jarkko@kernel.org>
Refactor EREMOVE out of sgx_free_epc_page() since it is only used in
one function.
I re-organized my Git a bit in order to keep track of things:
- 'master' bleading edge and 'next' ready PR ready branch
- 'numa' has nearly finished stuff, including the patches I'm
posting now.
jarkko@kernel.org (2):
x86/sgx: Remove a warn from sgx_free_epc_page()
x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
arch/x86/kernel/cpu/sgx/encl.c | 15 ++++++++++++++-
arch/x86/kernel/cpu/sgx/main.c | 12 ++++--------
2 files changed, 18 insertions(+), 9 deletions(-)
--
2.29.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v2 1/2] x86/sgx: Remove a warn from sgx_free_epc_page()
2021-01-12 23:33 [PATCH v2 0/2] Take away EREMOVE from sgx_free_epc_page() jarkko
@ 2021-01-12 23:33 ` jarkko
2021-01-12 23:33 ` [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE " jarkko
1 sibling, 0 replies; 6+ messages in thread
From: jarkko @ 2021-01-12 23:33 UTC (permalink / raw)
To: linux-sgx
Cc: dave.hansen, kai.huang, haitao.huang, jarkko, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, x86, H. Peter Anvin
From: "jarkko@kernel.org" <jarkko@kernel.org>
Remove SGX_EPC_PAGE_RECLAIMER_TRACKED check and warning. This cannot
happen, as enclave pages are freed only at the time when encl->refcount
triggers, i.e. when both VFS and the page reclaimer have given up on
their references.
Signed-off-by: jarkko@kernel.org <jarkko@kernel.org>
---
arch/x86/kernel/cpu/sgx/main.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index 0da510763c47..b2996cb63a8a 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -636,8 +636,6 @@ void sgx_free_epc_page(struct sgx_epc_page *page)
struct sgx_epc_section *section = &sgx_epc_sections[page->section];
int ret;
- WARN_ON_ONCE(page->flags & SGX_EPC_PAGE_RECLAIMER_TRACKED);
-
ret = __eremove(sgx_get_epc_virt_addr(page));
if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret))
return;
--
2.29.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
2021-01-12 23:33 [PATCH v2 0/2] Take away EREMOVE from sgx_free_epc_page() jarkko
2021-01-12 23:33 ` [PATCH v2 1/2] x86/sgx: Remove a warn " jarkko
@ 2021-01-12 23:33 ` jarkko
2021-01-13 1:09 ` Kai Huang
1 sibling, 1 reply; 6+ messages in thread
From: jarkko @ 2021-01-12 23:33 UTC (permalink / raw)
To: linux-sgx
Cc: dave.hansen, kai.huang, haitao.huang, jarkko, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, x86, H. Peter Anvin
From: "jarkko@kernel.org" <jarkko@kernel.org>
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@kernel.org <jarkko@kernel.org>
---
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);
kfree(va_page);
}
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index b2996cb63a8a..89d52fb56d4b 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -629,16 +629,14 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
* sgx_free_epc_page() - Free an EPC page
* @page: an EPC page
*
- * Call EREMOVE for an EPC page and insert it back to the list of free pages.
+ * Put the EPC page back to the list of free pages. It's the callers
+ * responsibility to make sure that the page is in uninitialized state In other
+ * words, do EREMOVE, EWB or whatever operation is necessary before calling
+ * this function.
*/
void sgx_free_epc_page(struct sgx_epc_page *page)
{
struct sgx_epc_section *section = &sgx_epc_sections[page->section];
- int ret;
-
- ret = __eremove(sgx_get_epc_virt_addr(page));
- if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret))
- return;
spin_lock(§ion->lock);
list_add_tail(&page->list, §ion->page_list);
--
2.29.2
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
2021-01-12 23:33 ` [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE " jarkko
@ 2021-01-13 1:09 ` Kai Huang
2021-01-13 21:08 ` Jarkko Sakkinen
0 siblings, 1 reply; 6+ messages in thread
From: Kai Huang @ 2021-01-13 1:09 UTC (permalink / raw)
To: jarkko
Cc: linux-sgx, dave.hansen, haitao.huang, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, x86, H. Peter Anvin
On Wed, 13 Jan 2021 01:33:51 +0200 jarkko@kernel.org wrote:
> From: "jarkko@kernel.org" <jarkko@kernel.org>
>
> 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@kernel.org <jarkko@kernel.org>
> ---
> 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.
> kfree(va_page);
> }
>
> diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
> index b2996cb63a8a..89d52fb56d4b 100644
> --- a/arch/x86/kernel/cpu/sgx/main.c
> +++ b/arch/x86/kernel/cpu/sgx/main.c
> @@ -629,16 +629,14 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
> * sgx_free_epc_page() - Free an EPC page
> * @page: an EPC page
> *
> - * Call EREMOVE for an EPC page and insert it back to the list of free pages.
> + * Put the EPC page back to the list of free pages. It's the callers
> + * responsibility to make sure that the page is in uninitialized state In other
> + * words, do EREMOVE, EWB or whatever operation is necessary before calling
> + * this function.
> */
> void sgx_free_epc_page(struct sgx_epc_page *page)
> {
> struct sgx_epc_section *section = &sgx_epc_sections[page->section];
> - int ret;
> -
> - ret = __eremove(sgx_get_epc_virt_addr(page));
> - if (WARN_ONCE(ret, "EREMOVE returned %d (0x%x)", ret, ret))
> - return;
>
> spin_lock(§ion->lock);
> list_add_tail(&page->list, §ion->page_list);
> --
> 2.29.2
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
2021-01-13 1:09 ` Kai Huang
@ 2021-01-13 21:08 ` Jarkko Sakkinen
2021-01-13 21:40 ` Kai Huang
0 siblings, 1 reply; 6+ messages in thread
From: Jarkko Sakkinen @ 2021-01-13 21:08 UTC (permalink / raw)
To: Kai Huang
Cc: linux-sgx, dave.hansen, haitao.huang, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, x86, H. Peter Anvin
On Wed, Jan 13, 2021 at 02:09:17PM +1300, Kai Huang wrote:
> On Wed, 13 Jan 2021 01:33:51 +0200 jarkko@kernel.org wrote:
> > From: "jarkko@kernel.org" <jarkko@kernel.org>
> >
> > 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@kernel.org <jarkko@kernel.org>
> > ---
> > 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.
/Jarkko
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE from sgx_free_epc_page()
2021-01-13 21:08 ` Jarkko Sakkinen
@ 2021-01-13 21:40 ` Kai Huang
0 siblings, 0 replies; 6+ messages in thread
From: Kai Huang @ 2021-01-13 21:40 UTC (permalink / raw)
To: Jarkko Sakkinen
Cc: linux-sgx, dave.hansen, haitao.huang, Thomas Gleixner,
Ingo Molnar, Borislav Petkov, x86, H. Peter Anvin
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@kernel.org wrote:
> > > From: "jarkko@kernel.org" <jarkko@kernel.org>
> > >
> > > 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@kernel.org <jarkko@kernel.org>
> > > ---
> > > 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.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-01-14 2:18 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2021-01-12 23:33 [PATCH v2 0/2] Take away EREMOVE from sgx_free_epc_page() jarkko
2021-01-12 23:33 ` [PATCH v2 1/2] x86/sgx: Remove a warn " jarkko
2021-01-12 23:33 ` [PATCH v2 2/2] x86/sgx: Wipe out EREMOVE " jarkko
2021-01-13 1:09 ` Kai Huang
2021-01-13 21:08 ` Jarkko Sakkinen
2021-01-13 21:40 ` Kai Huang
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