From bfec6c83077cd784fb049abbe2c5ff32629a7498 Mon Sep 17 00:00:00 2001 From: Rikard Falkeborn Date: Fri, 11 Sep 2020 22:35:07 +0200 Subject: virtio-balloon: Constify id_table id_table is not modified, so make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn Link: https://lore.kernel.org/r/20200911203509.26505-2-rikard.falkeborn@gmail.com Signed-off-by: Michael S. Tsirkin Acked-by: David Hildenbrand --- drivers/virtio/virtio_balloon.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 31cc97f2f515..481611c09dae 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -128,7 +128,7 @@ struct virtio_balloon { struct page_reporting_dev_info pr_dev_info; }; -static struct virtio_device_id id_table[] = { +static const struct virtio_device_id id_table[] = { { VIRTIO_ID_BALLOON, VIRTIO_DEV_ANY_ID }, { 0 }, }; -- cgit v1.2.3 From 7f90611693f08f6b29209bd8d704ee17cbe003a0 Mon Sep 17 00:00:00 2001 From: Rikard Falkeborn Date: Fri, 11 Sep 2020 22:35:08 +0200 Subject: virtio_input: Constify id_table id_table is not modified, so make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn Link: https://lore.kernel.org/r/20200911203509.26505-3-rikard.falkeborn@gmail.com Signed-off-by: Michael S. Tsirkin Reviewed-by: David Hildenbrand --- drivers/virtio/virtio_input.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c index 877b2ea3ed05..f1f6208edcf5 100644 --- a/drivers/virtio/virtio_input.c +++ b/drivers/virtio/virtio_input.c @@ -363,7 +363,7 @@ static int virtinput_restore(struct virtio_device *vdev) static unsigned int features[] = { /* none */ }; -static struct virtio_device_id id_table[] = { +static const struct virtio_device_id id_table[] = { { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID }, { 0 }, }; -- cgit v1.2.3 From 7ab4de60028e0e9669b72a5f69f2080f98069b04 Mon Sep 17 00:00:00 2001 From: Rikard Falkeborn Date: Fri, 11 Sep 2020 22:35:09 +0200 Subject: virtio-mem: Constify mem_id_table mem_id_table is not modified, so make it const to allow the compiler to put it in read-only memory. Signed-off-by: Rikard Falkeborn Link: https://lore.kernel.org/r/20200911203509.26505-4-rikard.falkeborn@gmail.com Signed-off-by: Michael S. Tsirkin Acked-by: David Hildenbrand --- drivers/virtio/virtio_mem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/virtio') diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c index c08512fcea90..8b6059dbc743 100644 --- a/drivers/virtio/virtio_mem.c +++ b/drivers/virtio/virtio_mem.c @@ -1957,7 +1957,7 @@ static unsigned int virtio_mem_features[] = { #endif }; -static struct virtio_device_id virtio_mem_id_table[] = { +static const struct virtio_device_id virtio_mem_id_table[] = { { VIRTIO_ID_MEM, VIRTIO_DEV_ANY_ID }, { 0 }, }; -- cgit v1.2.3 From 0afa15e1a5294754066343cad24af5ec8edae96d Mon Sep 17 00:00:00 2001 From: Pierre Morel Date: Thu, 10 Sep 2020 10:53:49 +0200 Subject: virtio: let arch advertise guest's memory access restrictions An architecture may restrict host access to guest memory, e.g. IBM s390 Secure Execution or AMD SEV. Provide a new Kconfig entry the architecture can select, CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS, when it provides the arch_has_restricted_virtio_memory_access callback to advertise to VIRTIO common code when the architecture restricts memory access from the host. The common code can then fail the probe for any device where VIRTIO_F_ACCESS_PLATFORM is required, but not set. Signed-off-by: Pierre Morel Reviewed-by: Cornelia Huck Reviewed-by: Halil Pasic Link: https://lore.kernel.org/r/1599728030-17085-2-git-send-email-pmorel@linux.ibm.com Signed-off-by: Michael S. Tsirkin Acked-by: Christian Borntraeger --- drivers/virtio/Kconfig | 6 ++++++ drivers/virtio/virtio.c | 15 +++++++++++++++ include/linux/virtio_config.h | 10 ++++++++++ 3 files changed, 31 insertions(+) (limited to 'drivers/virtio') diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig index 5c92e4a50882..ef2d49430800 100644 --- a/drivers/virtio/Kconfig +++ b/drivers/virtio/Kconfig @@ -6,6 +6,12 @@ config VIRTIO bus, such as CONFIG_VIRTIO_PCI, CONFIG_VIRTIO_MMIO, CONFIG_RPMSG or CONFIG_S390_GUEST. +config ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS + bool + help + This option is selected if the architecture may need to enforce + VIRTIO_F_ACCESS_PLATFORM + menuconfig VIRTIO_MENU bool "Virtio drivers" default y diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index a977e32a88f2..a2b3f12e10a2 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -176,6 +176,21 @@ int virtio_finalize_features(struct virtio_device *dev) if (ret) return ret; + ret = arch_has_restricted_virtio_memory_access(); + if (ret) { + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { + dev_warn(&dev->dev, + "device must provide VIRTIO_F_VERSION_1\n"); + return -ENODEV; + } + + if (!virtio_has_feature(dev, VIRTIO_F_ACCESS_PLATFORM)) { + dev_warn(&dev->dev, + "device must provide VIRTIO_F_ACCESS_PLATFORM\n"); + return -ENODEV; + } + } + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) return 0; diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index 8fe857e27ef3..3f697c8c8205 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -540,4 +540,14 @@ static inline void virtio_cwrite64(struct virtio_device *vdev, virtio_cread_le((vdev), structname, member, ptr); \ _r; \ }) + +#ifdef CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS +int arch_has_restricted_virtio_memory_access(void); +#else +static inline int arch_has_restricted_virtio_memory_access(void) +{ + return 0; +} +#endif /* CONFIG_ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS */ + #endif /* _LINUX_VIRTIO_CONFIG_H */ -- cgit v1.2.3