| Message ID | 1651947548-4055-5-git-send-email-olekstysh@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | virtio: Solution to restrict memory access under Xen using xen-grant DMA-mapping layer | expand |
On Sat, 7 May 2022, Oleksandr Tyshchenko wrote: > From: Juergen Gross <jgross@suse.com> > > In order to support virtio in Xen guests add a config option XEN_VIRTIO > enabling the user to specify whether in all Xen guests virtio should > be able to access memory via Xen grant mappings only on the host side. > > Also set PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS feature from the guest > initialization code on Arm and x86 if CONFIG_XEN_VIRTIO is enabled. > > Signed-off-by: Juergen Gross <jgross@suse.com> > Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> The patch looks OK to me Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> > --- > Changes V1 -> V2: > - new patch, split required changes from commit: > "[PATCH V1 3/6] xen/virtio: Add option to restrict memory access under Xen" > - rework according to new platform_has() infrastructure > --- > arch/arm/xen/enlighten.c | 2 ++ > arch/x86/xen/enlighten_hvm.c | 2 ++ > arch/x86/xen/enlighten_pv.c | 2 ++ > drivers/xen/Kconfig | 11 +++++++++++ > include/xen/xen.h | 8 ++++++++ > 5 files changed, 25 insertions(+) > > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > index 07eb69f..1f9c3ba 100644 > --- a/arch/arm/xen/enlighten.c > +++ b/arch/arm/xen/enlighten.c > @@ -443,6 +443,8 @@ static int __init xen_guest_init(void) > if (!xen_domain()) > return 0; > > + xen_set_restricted_virtio_memory_access(); > + > if (!acpi_disabled) > xen_acpi_guest_init(); > else > diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c > index 517a9d8..8b71b1d 100644 > --- a/arch/x86/xen/enlighten_hvm.c > +++ b/arch/x86/xen/enlighten_hvm.c > @@ -195,6 +195,8 @@ static void __init xen_hvm_guest_init(void) > if (xen_pv_domain()) > return; > > + xen_set_restricted_virtio_memory_access(); > + > init_hvm_pv_info(); > > reserve_shared_info(); > diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c > index 5038edb..fcd5d5d 100644 > --- a/arch/x86/xen/enlighten_pv.c > +++ b/arch/x86/xen/enlighten_pv.c > @@ -109,6 +109,8 @@ static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc); > > static void __init xen_pv_init_platform(void) > { > + xen_set_restricted_virtio_memory_access(); > + > populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP)); > > set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_start_info->shared_info); > diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig > index 313a9127..a7bd8ce 100644 > --- a/drivers/xen/Kconfig > +++ b/drivers/xen/Kconfig > @@ -339,4 +339,15 @@ config XEN_GRANT_DMA_OPS > bool > select DMA_OPS > > +config XEN_VIRTIO > + bool "Xen virtio support" > + depends on VIRTIO > + select XEN_GRANT_DMA_OPS > + help > + Enable virtio support for running as Xen guest. Depending on the > + guest type this will require special support on the backend side > + (qemu or kernel, depending on the virtio device types used). > + > + If in doubt, say n. > + > endmenu > diff --git a/include/xen/xen.h b/include/xen/xen.h > index a99bab8..0780a81 100644 > --- a/include/xen/xen.h > +++ b/include/xen/xen.h > @@ -52,6 +52,14 @@ bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, > extern u64 xen_saved_max_mem_size; > #endif > > +#include <linux/platform-feature.h> > + > +static inline void xen_set_restricted_virtio_memory_access(void) > +{ > + if (IS_ENABLED(CONFIG_XEN_VIRTIO) && xen_domain()) > + platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); > +} > + > #ifdef CONFIG_XEN_UNPOPULATED_ALLOC > int xen_alloc_unpopulated_pages(unsigned int nr_pages, struct page **pages); > void xen_free_unpopulated_pages(unsigned int nr_pages, struct page **pages);
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 07eb69f..1f9c3ba 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -443,6 +443,8 @@ static int __init xen_guest_init(void) if (!xen_domain()) return 0; + xen_set_restricted_virtio_memory_access(); + if (!acpi_disabled) xen_acpi_guest_init(); else diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c index 517a9d8..8b71b1d 100644 --- a/arch/x86/xen/enlighten_hvm.c +++ b/arch/x86/xen/enlighten_hvm.c @@ -195,6 +195,8 @@ static void __init xen_hvm_guest_init(void) if (xen_pv_domain()) return; + xen_set_restricted_virtio_memory_access(); + init_hvm_pv_info(); reserve_shared_info(); diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 5038edb..fcd5d5d 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -109,6 +109,8 @@ static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc); static void __init xen_pv_init_platform(void) { + xen_set_restricted_virtio_memory_access(); + populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP)); set_fixmap(FIX_PARAVIRT_BOOTMAP, xen_start_info->shared_info); diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 313a9127..a7bd8ce 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -339,4 +339,15 @@ config XEN_GRANT_DMA_OPS bool select DMA_OPS +config XEN_VIRTIO + bool "Xen virtio support" + depends on VIRTIO + select XEN_GRANT_DMA_OPS + help + Enable virtio support for running as Xen guest. Depending on the + guest type this will require special support on the backend side + (qemu or kernel, depending on the virtio device types used). + + If in doubt, say n. + endmenu diff --git a/include/xen/xen.h b/include/xen/xen.h index a99bab8..0780a81 100644 --- a/include/xen/xen.h +++ b/include/xen/xen.h @@ -52,6 +52,14 @@ bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, extern u64 xen_saved_max_mem_size; #endif +#include <linux/platform-feature.h> + +static inline void xen_set_restricted_virtio_memory_access(void) +{ + if (IS_ENABLED(CONFIG_XEN_VIRTIO) && xen_domain()) + platform_set(PLATFORM_VIRTIO_RESTRICTED_MEM_ACCESS); +} + #ifdef CONFIG_XEN_UNPOPULATED_ALLOC int xen_alloc_unpopulated_pages(unsigned int nr_pages, struct page **pages); void xen_free_unpopulated_pages(unsigned int nr_pages, struct page **pages);