Re: [Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
On Mon, Aug 19, 2019 at 06:57:06PM -0700, Roman Shaposhnik wrote:
> On Mon, Jul 22, 2019 at 8:33 AM Roger Pau Monne wrote:
> >
> > The current usage of need_iommu_pt_sync in p2m for non-translated
> > guests is wrong because it doesn't correctly handle a relaxed PV
> > hardware domain, that has need_sync set to false, but still need
> > entries to be added from calls to {set/clear}_identity_p2m_entry.
> >
> > Adjust the code in guest_physmap_add_page to also check whether the
> > domain has an iommu instead of whether it needs syncing or not in
> > order to take a reference to a page to be mapped.
> >
> > Signed-off-by: Roger Pau Monné
> > ---
> > Cc: George Dunlap
> > Cc: Jan Beulich
> > Cc: Andrew Cooper
> > Cc: Wei Liu
> > Cc: Paul Durrant
>
> Tested-by: Roman Shaposhnik
There's a v2 of the patch, but I guess your TB also applies to it.
Thanks, Roger.
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
On Mon, Jul 22, 2019 at 8:33 AM Roger Pau Monne wrote:
>
> The current usage of need_iommu_pt_sync in p2m for non-translated
> guests is wrong because it doesn't correctly handle a relaxed PV
> hardware domain, that has need_sync set to false, but still need
> entries to be added from calls to {set/clear}_identity_p2m_entry.
>
> Adjust the code in guest_physmap_add_page to also check whether the
> domain has an iommu instead of whether it needs syncing or not in
> order to take a reference to a page to be mapped.
>
> Signed-off-by: Roger Pau Monné
> ---
> Cc: George Dunlap
> Cc: Jan Beulich
> Cc: Andrew Cooper
> Cc: Wei Liu
> Cc: Paul Durrant
Tested-by: Roman Shaposhnik
> ---
> xen/arch/x86/mm/p2m.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
> index fef97c82f6..88a2430c8c 100644
> --- a/xen/arch/x86/mm/p2m.c
> +++ b/xen/arch/x86/mm/p2m.c
> @@ -836,7 +836,7 @@ guest_physmap_add_page(struct domain *d, gfn_t gfn, mfn_t
> mfn,
> */
> for ( i = 0; i < (1UL << page_order); ++i, ++page )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> /* nothing */;
> else if ( get_page_and_type(page, d, PGT_writable_page) )
> put_page_and_type(page);
> @@ -1341,7 +1341,7 @@ int set_identity_p2m_entry(struct domain *d, unsigned
> long gfn_l,
>
> if ( !paging_mode_translate(p2m->domain) )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> return 0;
> return iommu_legacy_map(d, _dfn(gfn_l), _mfn(gfn_l), PAGE_ORDER_4K,
> IOMMUF_readable | IOMMUF_writable);
> @@ -1432,7 +1432,7 @@ int clear_identity_p2m_entry(struct domain *d, unsigned
> long gfn_l)
>
> if ( !paging_mode_translate(d) )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> return 0;
> return iommu_legacy_unmap(d, _dfn(gfn_l), PAGE_ORDER_4K);
> }
> --
> 2.20.1 (Apple Git-117)
>
>
> ___
> Xen-devel mailing list
> Xen-devel@lists.xenproject.org
> https://lists.xenproject.org/mailman/listinfo/xen-devel
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
On Tue, Jul 23, 2019 at 10:32:41AM +, Jan Beulich wrote:
> On 22.07.2019 17:32, Roger Pau Monne wrote:
> > The current usage of need_iommu_pt_sync in p2m for non-translated
> > guests is wrong because it doesn't correctly handle a relaxed PV
> > hardware domain, that has need_sync set to false, but still need
> > entries to be added from calls to {set/clear}_identity_p2m_entry.
> >
> > Adjust the code in guest_physmap_add_page to also check whether the
> > domain has an iommu instead of whether it needs syncing or not in
> > order to take a reference to a page to be mapped.
>
> Why this seemingly unrelated change? I ask because ...
>
> > --- a/xen/arch/x86/mm/p2m.c
> > +++ b/xen/arch/x86/mm/p2m.c
> > @@ -836,7 +836,7 @@ guest_physmap_add_page(struct domain *d, gfn_t gfn,
> > mfn_t mfn,
> >*/
> > for ( i = 0; i < (1UL << page_order); ++i, ++page )
> > {
> > -if ( !need_iommu_pt_sync(d) )
> > +if ( !has_iommu_pt(d) )
> > /* nothing */;
> > else if ( get_page_and_type(page, d, PGT_writable_page) )
> > put_page_and_type(page);
>
> ... this parallels the code in iommu_hwdom_init(), which similarly
> uses need_iommu_pt_sync() (and during the prior discussion you did
> agree with Paul that it shouldn't be changed). IOW the patch for
> now can have my R-b only with this change and the respective part
> of the description dropped.
OK, this is again not needed for a relaxed PV hardware domain because
all RAM is already mapped on the iommu page tables.
Let me update the commit and resend.
Thanks, Roger.
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
On 22.07.2019 17:32, Roger Pau Monne wrote:
> The current usage of need_iommu_pt_sync in p2m for non-translated
> guests is wrong because it doesn't correctly handle a relaxed PV
> hardware domain, that has need_sync set to false, but still need
> entries to be added from calls to {set/clear}_identity_p2m_entry.
>
> Adjust the code in guest_physmap_add_page to also check whether the
> domain has an iommu instead of whether it needs syncing or not in
> order to take a reference to a page to be mapped.
Why this seemingly unrelated change? I ask because ...
> --- a/xen/arch/x86/mm/p2m.c
> +++ b/xen/arch/x86/mm/p2m.c
> @@ -836,7 +836,7 @@ guest_physmap_add_page(struct domain *d, gfn_t gfn, mfn_t
> mfn,
>*/
> for ( i = 0; i < (1UL << page_order); ++i, ++page )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> /* nothing */;
> else if ( get_page_and_type(page, d, PGT_writable_page) )
> put_page_and_type(page);
... this parallels the code in iommu_hwdom_init(), which similarly
uses need_iommu_pt_sync() (and during the prior discussion you did
agree with Paul that it shouldn't be changed). IOW the patch for
now can have my R-b only with this change and the respective part
of the description dropped.
Jan
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
> -Original Message-
> From: Roger Pau Monne
> Sent: 22 July 2019 16:32
> To: xen-devel@lists.xenproject.org
> Cc: Roger Pau Monne ; George Dunlap
> ; Jan Beulich
> ; Andrew Cooper ; Wei Liu
> ; Paul Durrant
>
> Subject: [PATCH] x86/p2m: fix non-translated handling of iommu mappings
>
> The current usage of need_iommu_pt_sync in p2m for non-translated
> guests is wrong because it doesn't correctly handle a relaxed PV
> hardware domain, that has need_sync set to false, but still need
> entries to be added from calls to {set/clear}_identity_p2m_entry.
>
> Adjust the code in guest_physmap_add_page to also check whether the
> domain has an iommu instead of whether it needs syncing or not in
> order to take a reference to a page to be mapped.
>
> Signed-off-by: Roger Pau Monné
> ---
> Cc: George Dunlap
> Cc: Jan Beulich
> Cc: Andrew Cooper
> Cc: Wei Liu
> Cc: Paul Durrant
Reviewed-by: Paul Durrant
> ---
> xen/arch/x86/mm/p2m.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
> index fef97c82f6..88a2430c8c 100644
> --- a/xen/arch/x86/mm/p2m.c
> +++ b/xen/arch/x86/mm/p2m.c
> @@ -836,7 +836,7 @@ guest_physmap_add_page(struct domain *d, gfn_t gfn, mfn_t
> mfn,
> */
> for ( i = 0; i < (1UL << page_order); ++i, ++page )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> /* nothing */;
> else if ( get_page_and_type(page, d, PGT_writable_page) )
> put_page_and_type(page);
> @@ -1341,7 +1341,7 @@ int set_identity_p2m_entry(struct domain *d, unsigned
> long gfn_l,
>
> if ( !paging_mode_translate(p2m->domain) )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> return 0;
> return iommu_legacy_map(d, _dfn(gfn_l), _mfn(gfn_l), PAGE_ORDER_4K,
> IOMMUF_readable | IOMMUF_writable);
> @@ -1432,7 +1432,7 @@ int clear_identity_p2m_entry(struct domain *d, unsigned
> long gfn_l)
>
> if ( !paging_mode_translate(d) )
> {
> -if ( !need_iommu_pt_sync(d) )
> +if ( !has_iommu_pt(d) )
> return 0;
> return iommu_legacy_unmap(d, _dfn(gfn_l), PAGE_ORDER_4K);
> }
> --
> 2.20.1 (Apple Git-117)
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
[Xen-devel] [PATCH] x86/p2m: fix non-translated handling of iommu mappings
The current usage of need_iommu_pt_sync in p2m for non-translated
guests is wrong because it doesn't correctly handle a relaxed PV
hardware domain, that has need_sync set to false, but still need
entries to be added from calls to {set/clear}_identity_p2m_entry.
Adjust the code in guest_physmap_add_page to also check whether the
domain has an iommu instead of whether it needs syncing or not in
order to take a reference to a page to be mapped.
Signed-off-by: Roger Pau Monné
---
Cc: George Dunlap
Cc: Jan Beulich
Cc: Andrew Cooper
Cc: Wei Liu
Cc: Paul Durrant
---
xen/arch/x86/mm/p2m.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index fef97c82f6..88a2430c8c 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -836,7 +836,7 @@ guest_physmap_add_page(struct domain *d, gfn_t gfn, mfn_t
mfn,
*/
for ( i = 0; i < (1UL << page_order); ++i, ++page )
{
-if ( !need_iommu_pt_sync(d) )
+if ( !has_iommu_pt(d) )
/* nothing */;
else if ( get_page_and_type(page, d, PGT_writable_page) )
put_page_and_type(page);
@@ -1341,7 +1341,7 @@ int set_identity_p2m_entry(struct domain *d, unsigned
long gfn_l,
if ( !paging_mode_translate(p2m->domain) )
{
-if ( !need_iommu_pt_sync(d) )
+if ( !has_iommu_pt(d) )
return 0;
return iommu_legacy_map(d, _dfn(gfn_l), _mfn(gfn_l), PAGE_ORDER_4K,
IOMMUF_readable | IOMMUF_writable);
@@ -1432,7 +1432,7 @@ int clear_identity_p2m_entry(struct domain *d, unsigned
long gfn_l)
if ( !paging_mode_translate(d) )
{
-if ( !need_iommu_pt_sync(d) )
+if ( !has_iommu_pt(d) )
return 0;
return iommu_legacy_unmap(d, _dfn(gfn_l), PAGE_ORDER_4K);
}
--
2.20.1 (Apple Git-117)
___
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
