diff options
| -rw-r--r-- | MAINTAINERS | 7 | ||||
| -rw-r--r-- | drivers/firmware/qemu_fw_cfg.c | 24 | ||||
| -rw-r--r-- | drivers/virtio/virtio_pci_modern.c | 11 | ||||
| -rw-r--r-- | include/uapi/linux/virtio_config.h | 2 |
4 files changed, 40 insertions, 4 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index 40eb1dbe2ae5..d8c901bbec89 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9142,6 +9142,13 @@ T: git git://github.com/KrasnikovEugene/wcn36xx.git S: Supported F: drivers/net/wireless/ath/wcn36xx/ +QEMU MACHINE EMULATOR AND VIRTUALIZER SUPPORT +M: Gabriel Somlo <somlo@cmu.edu> +M: "Michael S. Tsirkin" <mst@redhat.com> +L: qemu-devel@nongnu.org +S: Maintained +F: drivers/firmware/qemu_fw_cfg.c + RADOS BLOCK DEVICE (RBD) M: Ilya Dryomov <idryomov@gmail.com> M: Sage Weil <sage@redhat.com> diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c index fedbff55a7f3..815c4a5cae54 100644 --- a/drivers/firmware/qemu_fw_cfg.c +++ b/drivers/firmware/qemu_fw_cfg.c @@ -77,12 +77,28 @@ static inline u16 fw_cfg_sel_endianness(u16 key) static inline void fw_cfg_read_blob(u16 key, void *buf, loff_t pos, size_t count) { + u32 glk; + acpi_status status; + + /* If we have ACPI, ensure mutual exclusion against any potential + * device access by the firmware, e.g. via AML methods: + */ + status = acpi_acquire_global_lock(ACPI_WAIT_FOREVER, &glk); + if (ACPI_FAILURE(status) && status != AE_NOT_CONFIGURED) { + /* Should never get here */ + WARN(1, "fw_cfg_read_blob: Failed to lock ACPI!\n"); + memset(buf, 0, count); + return; + } + mutex_lock(&fw_cfg_dev_lock); iowrite16(fw_cfg_sel_endianness(key), fw_cfg_reg_ctrl); while (pos-- > 0) ioread8(fw_cfg_reg_data); ioread8_rep(fw_cfg_reg_data, buf, count); mutex_unlock(&fw_cfg_dev_lock); + + acpi_release_global_lock(glk); } /* clean up fw_cfg device i/o */ @@ -727,12 +743,18 @@ device_param_cb(mmio, &fw_cfg_cmdline_param_ops, NULL, S_IRUSR); static int __init fw_cfg_sysfs_init(void) { + int ret; + /* create /sys/firmware/qemu_fw_cfg/ top level directory */ fw_cfg_top_ko = kobject_create_and_add("qemu_fw_cfg", firmware_kobj); if (!fw_cfg_top_ko) return -ENOMEM; - return platform_driver_register(&fw_cfg_sysfs_driver); + ret = platform_driver_register(&fw_cfg_sysfs_driver); + if (ret) + fw_cfg_kobj_cleanup(fw_cfg_top_ko); + + return ret; } static void __exit fw_cfg_sysfs_exit(void) diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index f6f28cc7eb45..e76bd91a29da 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -17,6 +17,7 @@ * */ +#include <linux/delay.h> #define VIRTIO_PCI_NO_LEGACY #include "virtio_pci_common.h" @@ -271,9 +272,13 @@ static void vp_reset(struct virtio_device *vdev) struct virtio_pci_device *vp_dev = to_vp_device(vdev); /* 0 status means a reset. */ vp_iowrite8(0, &vp_dev->common->device_status); - /* Flush out the status write, and flush in device writes, - * including MSI-X interrupts, if any. */ - vp_ioread8(&vp_dev->common->device_status); + /* After writing 0 to device_status, the driver MUST wait for a read of + * device_status to return 0 before reinitializing the device. + * This will flush out the status write, and flush in device writes, + * including MSI-X interrupts, if any. + */ + while (vp_ioread8(&vp_dev->common->device_status)) + msleep(1); /* Flush pending VQ/configuration callbacks. */ vp_synchronize_vectors(vdev); } diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h index c18264df9504..4cb65bbfa654 100644 --- a/include/uapi/linux/virtio_config.h +++ b/include/uapi/linux/virtio_config.h @@ -40,6 +40,8 @@ #define VIRTIO_CONFIG_S_DRIVER_OK 4 /* Driver has finished configuring features */ #define VIRTIO_CONFIG_S_FEATURES_OK 8 +/* Device entered invalid state, driver must reset it */ +#define VIRTIO_CONFIG_S_NEEDS_RESET 0x40 /* We've given up on this device. */ #define VIRTIO_CONFIG_S_FAILED 0x80 |