On 15-06-22, 10:48, Juergen Gross wrote:
> Commit fa1f57421e0b ("xen/virtio: Enable restricted memory access using
> Xen grant mappings") introduced a new requirement for using virtio
> devices: the backend now needs to support the VIRTIO_F_ACCESS_PLATFORM
> feature.
>
> This is an undue requirement for non-PV guests, as those can be operated
> with existing backends without any problem, as long as those backends
> are running in dom0.
>
> Per default allow virtio devices without grant support for non-PV
> guests.
>
> The setting can be overridden by using the new "xen_virtio_grant"
> command line parameter.
>
> Add a new config item to always force use of grants for virtio.
>
> Fixes: fa1f57421e0b ("xen/virtio: Enable restricted memory access using Xen grant mappings")
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---
> .../admin-guide/kernel-parameters.txt | 6 +++++
> drivers/xen/Kconfig | 9 ++++++++
> drivers/xen/grant-dma-ops.c | 22 +++++++++++++++++++
> include/xen/xen.h | 12 +++++-----
> 4 files changed, 42 insertions(+), 7 deletions(-)
Thanks for the quick fix.
With CONFIG_DEBUG_SECTION_MISMATCH=y, this generates a warning.
WARNING: modpost: vmlinux.o(.text+0x7a8270): Section mismatch in reference from the function xen_set_restricted_virtio_memory_access() to the variable .init.data:xen_virtio_grants
The function xen_set_restricted_virtio_memory_access() references
the variable __initdata xen_virtio_grants.
This is often because xen_set_restricted_virtio_memory_access lacks a __initdata
annotation or the annotation of xen_virtio_grants is wrong.
This can be fixed by:
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c
index d1fae789dfad..1099097b4515 100644
--- a/drivers/xen/grant-dma-ops.c
+++ b/drivers/xen/grant-dma-ops.c
@@ -42,7 +42,7 @@ static __init int parse_use_grants(char *arg)
}
early_param("xen_virtio_grant", parse_use_grants);
-void xen_set_restricted_virtio_memory_access(void)
+void __init xen_set_restricted_virtio_memory_access(void)
{
if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_virtio_grants ||
(!xen_virtio_grants_set && xen_pv_domain()))
With that:
Tested-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
--
viresh
