From 266d4c1359d00f35c2b26556b01b857456537294 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Mon, 24 May 2010 20:01:08 -0300 Subject: [PATCH 3/3] device-assignment: add config fd qdev property RH-Author: Alex Williamson Message-id: <20100524200108.23875.54793.stgit@virtlab9.virt.bos.redhat.com> Patchwork-id: 9516 O-Subject: [RHEL6.0 qemu-kvm PATCH 3/3] device-assignment: add config fd qdev property Bugzilla: 595495 RH-Acked-by: Don Dutile RH-Acked-by: Jes Sorensen RH-Acked-by: Juan Quintela Bugzilla: 595495 Upstream status: submitted When libvirt launches a guest it first chowns the relevenat /sys/bus/pci/.../config file for an assigned device then drops privileges. This causes an issue for device assignment because despite being file owner, the sysfs config space file checks for CAP_SYS_ADMIN before allowing access to device dependent config space. This adds a new qdev configfd property which allows libvirt to open the sysfs config space file and give qemu an already opened file descriptor. Along with a change pending for the 2.6.35 kernel, this allows the capability check to compare against privileges from when the file was opened. Signed-off-by: Chris Wright Signed-off-by: Alex Williamson --- hw/device-assignment.c | 28 ++++++++++++++++++++++------ hw/device-assignment.h | 1 + 2 files changed, 23 insertions(+), 6 deletions(-) Signed-off-by: Eduardo Habkost --- hw/device-assignment.c | 28 ++++++++++++++++++++++------ hw/device-assignment.h | 1 + 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/hw/device-assignment.c b/hw/device-assignment.c index 9f59062..d05fd0f 100644 --- a/hw/device-assignment.c +++ b/hw/device-assignment.c @@ -37,6 +37,7 @@ #include "console.h" #include "device-assignment.h" #include "loader.h" +#include "monitor.h" #include /* From linux/ioport.h */ @@ -511,14 +512,28 @@ static int get_real_device(AssignedDevice *pci_dev, uint8_t r_bus, snprintf(name, sizeof(name), "%sconfig", dir); - fd = open(name, O_RDWR); - if (fd == -1) { - fprintf(stderr, "%s: %s: %m\n", __func__, name); - return 1; + if (pci_dev->configfd_name && *pci_dev->configfd_name) { + if (qemu_isdigit(pci_dev->configfd_name[0])) { + dev->config_fd = strtol(pci_dev->configfd_name, NULL, 0); + } else { + dev->config_fd = monitor_get_fd(cur_mon, pci_dev->configfd_name); + if (dev->config_fd < 0) { + fprintf(stderr, "%s: (%s) unkown\n", __func__, + pci_dev->configfd_name); + return 1; + } + } + } else { + dev->config_fd = open(name, O_RDWR); + + if (dev->config_fd == -1) { + fprintf(stderr, "%s: %s: %m\n", __func__, name); + return 1; + } } - dev->config_fd = fd; again: - r = read(fd, pci_dev->dev.config, pci_config_size(&pci_dev->dev)); + r = read(dev->config_fd, pci_dev->dev.config, + pci_config_size(&pci_dev->dev)); if (r < 0) { if (errno == EINTR || errno == EAGAIN) goto again; @@ -1272,6 +1287,7 @@ static PCIDeviceInfo assign_info = { .qdev.props = (Property[]) { DEFINE_PROP("host", AssignedDevice, host, qdev_prop_hostaddr, PCIHostDevice), DEFINE_PROP_UINT32("iommu", AssignedDevice, use_iommu, 1), + DEFINE_PROP_STRING("configfd", AssignedDevice, configfd_name), DEFINE_PROP_END_OF_LIST(), }, }; diff --git a/hw/device-assignment.h b/hw/device-assignment.h index 40ba09d..b3ef4db 100644 --- a/hw/device-assignment.h +++ b/hw/device-assignment.h @@ -101,6 +101,7 @@ typedef struct AssignedDevice { target_phys_addr_t msix_table_addr; int mmio_index; int need_emulate_cmd; + char *configfd_name; QLIST_ENTRY(AssignedDevice) next; } AssignedDevice; -- 1.7.0.3