summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDavid Marchand <david.marchand@redhat.com>2019-07-10 14:33:40 +0200
committerThomas Monjalon <thomas@monjalon.net>2019-07-10 18:53:47 +0200
commit89aac60e0be9ed95a87b16e3595f102f9faaffb4 (patch)
treea087bc966c5e4b344a07376e50ee236c79ddfa77
parentd34b50181d188a17b6273ea9fcd86897a9c98872 (diff)
downloaddpdk-89aac60e0be9ed95a87b16e3595f102f9faaffb4.zip
dpdk-89aac60e0be9ed95a87b16e3595f102f9faaffb4.tar.gz
dpdk-89aac60e0be9ed95a87b16e3595f102f9faaffb4.tar.xz
vfio: fix interrupts race condition
Populating the eventfd in rte_intr_enable in each request to vfio triggers a reconfiguration of the interrupt handler on the kernel side. The problem is that rte_intr_enable is often used to re-enable masked interrupts from drivers interrupt handlers. This reconfiguration leaves a window during which a device could send an interrupt and then the kernel logs this (unsolicited from the kernel point of view) interrupt: [158764.159833] do_IRQ: 9.34 No irq handler for vector VFIO api makes it possible to set the fd at setup time. Make use of this and then we only need to ask for masking/unmasking legacy interrupts and we have nothing to do for MSI/MSIX. "rxtx" interrupts are left untouched but are most likely subject to the same issue. Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=1654824 Fixes: 5c782b3928b8 ("vfio: interrupts") Cc: stable@dpdk.org Signed-off-by: David Marchand <david.marchand@redhat.com> Tested-by: Shahed Shaikh <shshaikh@marvell.com>
-rw-r--r--drivers/bus/pci/linux/pci_vfio.c78
-rw-r--r--lib/librte_eal/linux/eal/eal_interrupts.c197
2 files changed, 86 insertions, 189 deletions
diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
index 1ceb1c0..ee31239 100644
--- a/drivers/bus/pci/linux/pci_vfio.c
+++ b/drivers/bus/pci/linux/pci_vfio.c
@@ -187,8 +187,11 @@ pci_vfio_set_bus_master(int dev_fd, bool op)
static int
pci_vfio_setup_interrupts(struct rte_pci_device *dev, int vfio_dev_fd)
{
- int i, ret, intr_idx;
+ char irq_set_buf[sizeof(struct vfio_irq_set) + sizeof(int)];
+ struct vfio_irq_set *irq_set;
enum rte_intr_mode intr_mode;
+ int i, ret, intr_idx;
+ int fd;
/* default to invalid index */
intr_idx = VFIO_PCI_NUM_IRQS;
@@ -220,7 +223,6 @@ pci_vfio_setup_interrupts(struct rte_pci_device *dev, int vfio_dev_fd)
/* start from MSI-X interrupt type */
for (i = VFIO_PCI_MSIX_IRQ_INDEX; i >= 0; i--) {
struct vfio_irq_info irq = { .argsz = sizeof(irq) };
- int fd = -1;
/* skip interrupt modes we don't want */
if (intr_mode != RTE_INTR_MODE_NONE &&
@@ -236,51 +238,51 @@ pci_vfio_setup_interrupts(struct rte_pci_device *dev, int vfio_dev_fd)
return -1;
}
+ /* found a usable interrupt mode */
+ if ((irq.flags & VFIO_IRQ_INFO_EVENTFD) != 0)
+ break;
+
/* if this vector cannot be used with eventfd, fail if we explicitly
* specified interrupt type, otherwise continue */
- if ((irq.flags & VFIO_IRQ_INFO_EVENTFD) == 0) {
- if (intr_mode != RTE_INTR_MODE_NONE) {
- RTE_LOG(ERR, EAL,
- " interrupt vector does not support eventfd!\n");
- return -1;
- } else
- continue;
- }
-
- /* set up an eventfd for interrupts */
- fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
- if (fd < 0) {
- RTE_LOG(ERR, EAL, " cannot set up eventfd, "
- "error %i (%s)\n", errno, strerror(errno));
+ if (intr_mode != RTE_INTR_MODE_NONE) {
+ RTE_LOG(ERR, EAL, " interrupt vector does not support eventfd!\n");
return -1;
}
+ }
- dev->intr_handle.fd = fd;
- dev->intr_handle.vfio_dev_fd = vfio_dev_fd;
+ if (i < 0)
+ return -1;
- switch (i) {
- case VFIO_PCI_MSIX_IRQ_INDEX:
- intr_mode = RTE_INTR_MODE_MSIX;
- dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSIX;
- break;
- case VFIO_PCI_MSI_IRQ_INDEX:
- intr_mode = RTE_INTR_MODE_MSI;
- dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSI;
- break;
- case VFIO_PCI_INTX_IRQ_INDEX:
- intr_mode = RTE_INTR_MODE_LEGACY;
- dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_LEGACY;
- break;
- default:
- RTE_LOG(ERR, EAL, " unknown interrupt type!\n");
- return -1;
- }
+ fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
+ if (fd < 0) {
+ RTE_LOG(ERR, EAL, " cannot set up eventfd, error %i (%s)\n",
+ errno, strerror(errno));
+ return -1;
+ }
- return 0;
+ irq_set = (struct vfio_irq_set *)irq_set_buf;
+ irq_set->argsz = sizeof(irq_set_buf);
+ irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD|VFIO_IRQ_SET_ACTION_TRIGGER;
+ irq_set->index = i;
+ irq_set->start = 0;
+ irq_set->count = 1;
+ memcpy(&irq_set->data, &fd, sizeof(int));
+ if (ioctl(vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set) < 0) {
+ RTE_LOG(ERR, EAL, " error configuring interrupt\n");
+ close(fd);
+ return -1;
}
- /* if we're here, we haven't found a suitable interrupt vector */
- return -1;
+ dev->intr_handle.fd = fd;
+ dev->intr_handle.vfio_dev_fd = vfio_dev_fd;
+ if (i == VFIO_PCI_MSIX_IRQ_INDEX)
+ dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSIX;
+ else if (i == VFIO_PCI_MSI_IRQ_INDEX)
+ dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_MSI;
+ else if (i == VFIO_PCI_INTX_IRQ_INDEX)
+ dev->intr_handle.type = RTE_INTR_HANDLE_VFIO_LEGACY;
+
+ return 0;
}
#ifdef HAVE_VFIO_DEV_REQ_INTERFACE
diff --git a/lib/librte_eal/linux/eal/eal_interrupts.c b/lib/librte_eal/linux/eal/eal_interrupts.c
index 79ad5e8..27976b3 100644
--- a/lib/librte_eal/linux/eal/eal_interrupts.c
+++ b/lib/librte_eal/linux/eal/eal_interrupts.c
@@ -109,42 +109,19 @@ static pthread_t intr_thread;
/* enable legacy (INTx) interrupts */
static int
-vfio_enable_intx(const struct rte_intr_handle *intr_handle) {
- struct vfio_irq_set *irq_set;
- char irq_set_buf[IRQ_SET_BUF_LEN];
- int len, ret;
- int *fd_ptr;
-
- len = sizeof(irq_set_buf);
-
- /* enable INTx */
- irq_set = (struct vfio_irq_set *) irq_set_buf;
- irq_set->argsz = len;
- irq_set->count = 1;
- irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
- irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
- irq_set->start = 0;
- fd_ptr = (int *) &irq_set->data;
- *fd_ptr = intr_handle->fd;
-
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
- if (ret) {
- RTE_LOG(ERR, EAL, "Error enabling INTx interrupts for fd %d\n",
- intr_handle->fd);
- return -1;
- }
+vfio_enable_intx(const struct rte_intr_handle *intr_handle)
+{
+ struct vfio_irq_set irq_set;
+ int ret;
- /* unmask INTx after enabling */
- memset(irq_set, 0, len);
- len = sizeof(struct vfio_irq_set);
- irq_set->argsz = len;
- irq_set->count = 1;
- irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK;
- irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
- irq_set->start = 0;
+ /* unmask INTx */
+ irq_set.argsz = sizeof(irq_set);
+ irq_set.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK;
+ irq_set.index = VFIO_PCI_INTX_IRQ_INDEX;
+ irq_set.start = 0;
+ irq_set.count = 1;
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
if (ret) {
RTE_LOG(ERR, EAL, "Error unmasking INTx interrupts for fd %d\n",
@@ -156,128 +133,51 @@ vfio_enable_intx(const struct rte_intr_handle *intr_handle) {
/* disable legacy (INTx) interrupts */
static int
-vfio_disable_intx(const struct rte_intr_handle *intr_handle) {
- struct vfio_irq_set *irq_set;
- char irq_set_buf[IRQ_SET_BUF_LEN];
- int len, ret;
-
- len = sizeof(struct vfio_irq_set);
+vfio_disable_intx(const struct rte_intr_handle *intr_handle)
+{
+ struct vfio_irq_set irq_set;
+ int ret;
- /* mask interrupts before disabling */
- irq_set = (struct vfio_irq_set *) irq_set_buf;
- irq_set->argsz = len;
- irq_set->count = 1;
- irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK;
- irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
- irq_set->start = 0;
+ /* mask interrupts */
+ irq_set.argsz = sizeof(irq_set);
+ irq_set.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK;
+ irq_set.index = VFIO_PCI_INTX_IRQ_INDEX;
+ irq_set.start = 0;
+ irq_set.count = 1;
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
if (ret) {
RTE_LOG(ERR, EAL, "Error masking INTx interrupts for fd %d\n",
intr_handle->fd);
return -1;
}
-
- /* disable INTx*/
- memset(irq_set, 0, len);
- irq_set->argsz = len;
- irq_set->count = 0;
- irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
- irq_set->index = VFIO_PCI_INTX_IRQ_INDEX;
- irq_set->start = 0;
-
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
- if (ret) {
- RTE_LOG(ERR, EAL,
- "Error disabling INTx interrupts for fd %d\n", intr_handle->fd);
- return -1;
- }
- return 0;
-}
-
-/* enable MSI interrupts */
-static int
-vfio_enable_msi(const struct rte_intr_handle *intr_handle) {
- int len, ret;
- char irq_set_buf[IRQ_SET_BUF_LEN];
- struct vfio_irq_set *irq_set;
- int *fd_ptr;
-
- len = sizeof(irq_set_buf);
-
- irq_set = (struct vfio_irq_set *) irq_set_buf;
- irq_set->argsz = len;
- irq_set->count = 1;
- irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
- irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
- irq_set->start = 0;
- fd_ptr = (int *) &irq_set->data;
- *fd_ptr = intr_handle->fd;
-
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
- if (ret) {
- RTE_LOG(ERR, EAL, "Error enabling MSI interrupts for fd %d\n",
- intr_handle->fd);
- return -1;
- }
return 0;
}
-/* disable MSI interrupts */
-static int
-vfio_disable_msi(const struct rte_intr_handle *intr_handle) {
- struct vfio_irq_set *irq_set;
- char irq_set_buf[IRQ_SET_BUF_LEN];
- int len, ret;
-
- len = sizeof(struct vfio_irq_set);
-
- irq_set = (struct vfio_irq_set *) irq_set_buf;
- irq_set->argsz = len;
- irq_set->count = 0;
- irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
- irq_set->index = VFIO_PCI_MSI_IRQ_INDEX;
- irq_set->start = 0;
-
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
- if (ret)
- RTE_LOG(ERR, EAL,
- "Error disabling MSI interrupts for fd %d\n", intr_handle->fd);
-
- return ret;
-}
-
/* enable MSI-X interrupts */
static int
-vfio_enable_msix(const struct rte_intr_handle *intr_handle) {
- int len, ret;
+vfio_enable_msix(const struct rte_intr_handle *intr_handle)
+{
char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
struct vfio_irq_set *irq_set;
- int *fd_ptr;
+ int len, ret;
+
+ if (intr_handle->nb_efd == 0)
+ return 0;
len = sizeof(irq_set_buf);
irq_set = (struct vfio_irq_set *) irq_set_buf;
irq_set->argsz = len;
- /* 0 < irq_set->count < RTE_MAX_RXTX_INTR_VEC_ID + 1 */
- irq_set->count = intr_handle->max_intr ?
- (intr_handle->max_intr > RTE_MAX_RXTX_INTR_VEC_ID + 1 ?
- RTE_MAX_RXTX_INTR_VEC_ID + 1 : intr_handle->max_intr) : 1;
irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | VFIO_IRQ_SET_ACTION_TRIGGER;
irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
- irq_set->start = 0;
- fd_ptr = (int *) &irq_set->data;
- /* INTR vector offset 0 reserve for non-efds mapping */
- fd_ptr[RTE_INTR_VEC_ZERO_OFFSET] = intr_handle->fd;
- memcpy(&fd_ptr[RTE_INTR_VEC_RXTX_OFFSET], intr_handle->efds,
- sizeof(*intr_handle->efds) * intr_handle->nb_efd);
+ irq_set->start = RTE_INTR_VEC_RXTX_OFFSET;
+ irq_set->count = intr_handle->nb_efd;
+ memcpy(&irq_set->data, intr_handle->efds,
+ sizeof(*intr_handle->efds) * intr_handle->nb_efd);
ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
if (ret) {
RTE_LOG(ERR, EAL, "Error enabling MSI-X interrupts for fd %d\n",
intr_handle->fd);
@@ -289,22 +189,21 @@ vfio_enable_msix(const struct rte_intr_handle *intr_handle) {
/* disable MSI-X interrupts */
static int
-vfio_disable_msix(const struct rte_intr_handle *intr_handle) {
- struct vfio_irq_set *irq_set;
- char irq_set_buf[MSIX_IRQ_SET_BUF_LEN];
- int len, ret;
-
- len = sizeof(struct vfio_irq_set);
+vfio_disable_msix(const struct rte_intr_handle *intr_handle)
+{
+ struct vfio_irq_set irq_set;
+ int ret;
- irq_set = (struct vfio_irq_set *) irq_set_buf;
- irq_set->argsz = len;
- irq_set->count = 0;
- irq_set->flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
- irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
- irq_set->start = 0;
+ if (intr_handle->nb_efd == 0)
+ return 0;
- ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ irq_set.argsz = sizeof(irq_set);
+ irq_set.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER;
+ irq_set.index = VFIO_PCI_MSIX_IRQ_INDEX;
+ irq_set.start = RTE_INTR_VEC_RXTX_OFFSET;
+ irq_set.count = intr_handle->nb_efd;
+ ret = ioctl(intr_handle->vfio_dev_fd, VFIO_DEVICE_SET_IRQS, &irq_set);
if (ret)
RTE_LOG(ERR, EAL,
"Error disabling MSI-X interrupts for fd %d\n", intr_handle->fd);
@@ -665,9 +564,7 @@ rte_intr_enable(const struct rte_intr_handle *intr_handle)
return -1;
break;
case RTE_INTR_HANDLE_VFIO_MSI:
- if (vfio_enable_msi(intr_handle))
- return -1;
- break;
+ return 0;
case RTE_INTR_HANDLE_VFIO_LEGACY:
if (vfio_enable_intx(intr_handle))
return -1;
@@ -721,9 +618,7 @@ rte_intr_disable(const struct rte_intr_handle *intr_handle)
return -1;
break;
case RTE_INTR_HANDLE_VFIO_MSI:
- if (vfio_disable_msi(intr_handle))
- return -1;
- break;
+ return 0;
case RTE_INTR_HANDLE_VFIO_LEGACY:
if (vfio_disable_intx(intr_handle))
return -1;