From 266d4c1359d00f35c2b26556b01b857456537294 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Mon, 24 May 2010 20:01:08 -0300
Subject: [PATCH 3/3] device-assignment: add config fd qdev property
RH-Author: Alex Williamson <alex.williamson@redhat.com>
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 <ddutile@redhat.com>
RH-Acked-by: Jes Sorensen <Jes.Sorensen@redhat.com>
RH-Acked-by: Juan Quintela <quintela@redhat.com>
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 <chrisw@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---
hw/device-assignment.c | 28 ++++++++++++++++++++++------
hw/device-assignment.h | 1 +
2 files changed, 23 insertions(+), 6 deletions(-)
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
---
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 <pci/header.h>
/* 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