> -----Original Message----- > From: Alex Williamson [mailto:alex.williamson@xxxxxxxxxx] > Sent: Wednesday, January 09, 2013 10:08 AM > To: Pandarathil, Vijaymohan R > Cc: Bjorn Helgaas; Gleb Natapov; kvm@xxxxxxxxxxxxxxx; qemu- > devel@xxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 2/2] QEMU-AER: Qemu changes to support AER for VFIO-PCI > devices > > On Wed, 2013-01-09 at 06:26 +0000, Pandarathil, Vijaymohan R wrote: > > - Create eventfd per vfio device assigned to a guest and register an > > event handler > > > > - This fd is passed to the vfio_pci driver through a new ioctl > > > > - When the device encounters an error, the eventfd is signaled > > and the qemu eventfd handler gets invoked. > > > > - In the handler decide what action to take. Current action taken > > is to terminate the guest. > > > > Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@xxxxxx> > > --- > > hw/vfio_pci.c | 56 > ++++++++++++++++++++++++++++++++++++++++++++++ > > linux-headers/linux/vfio.h | 9 ++++++++ > > 2 files changed, 65 insertions(+) > > > > diff --git a/hw/vfio_pci.c b/hw/vfio_pci.c > > index 28c8303..9c3c28b 100644 > > --- a/hw/vfio_pci.c > > +++ b/hw/vfio_pci.c > > @@ -38,6 +38,7 @@ > > #include "qemu/error-report.h" > > #include "qemu/queue.h" > > #include "qemu/range.h" > > +#include "sysemu/sysemu.h" > > > > /* #define DEBUG_VFIO */ > > #ifdef DEBUG_VFIO > > @@ -130,6 +131,8 @@ typedef struct VFIODevice { > > QLIST_ENTRY(VFIODevice) next; > > struct VFIOGroup *group; > > bool reset_works; > > + EventNotifier errfd; > > Misleading name, it's an EventNotifier not an fd. Will make the change. > > > + __u32 dev_info_flags; > > } VFIODevice; > > > > typedef struct VFIOGroup { > > @@ -1805,6 +1808,8 @@ static int vfio_get_device(VFIOGroup *group, const > char *name, VFIODevice *vdev) > > DPRINTF("Device %s flags: %u, regions: %u, irgs: %u\n", name, > > dev_info.flags, dev_info.num_regions, dev_info.num_irqs); > > > > + vdev->dev_info_flags = dev_info.flags; > > + > > We test the VFIO_DEVICE_FLAGS_RESET elsewhere by caching the bit into a > variable, why not do that here too? I was wondering if there was any specific reason to cache the bit into a separate variable. Wouldn't a flags field which can contain the specific bit be more apt ? > > > if (!(dev_info.flags & VFIO_DEVICE_FLAGS_PCI)) { > > error_report("vfio: Um, this isn't a PCI device\n"); > > goto error; > > @@ -1900,6 +1905,55 @@ static void vfio_put_device(VFIODevice *vdev) > > } > > } > > > > +static void vfio_errfd_handler(void *opaque) > > +{ > > + VFIODevice *vdev = opaque; > > + > > + if (!event_notifier_test_and_clear(&vdev->errfd)) { > > + return; > > + } > > + > > + /* > > + * TBD. Retrieve the error details and decide what action > > + * needs to be taken. One of the actions could be to pass > > + * the error to the guest and have the guest driver recover > > + * the error. This requires that PCIe capabilities be > > + * exposed to the guest. At present, we just terminate the > > + * guest to contain the error. > > + */ > > + error_report("%s(%04x:%02x:%02x.%x) " > > + "Unrecoverable error detected... Terminating guest\n", > > + __func__, vdev->host.domain, vdev->host.bus, vdev->host.slot, > > + vdev->host.function); > > + > > + qemu_system_shutdown_request(); > > I would have figured hw_error Hw_error() is probably more appropriate. Will make the change. > > > + return; > > +} > > + > > +static void vfio_register_errfd(VFIODevice *vdev) > > +{ > > + int32_t pfd; > > "pfd" is used elsewhere in vfio as "Pointer to FD", this is just a fd. Will change. > > > + int ret; > > + > > + if (!(vdev->dev_info_flags & VFIO_DEVICE_FLAGS_AER_NOTIFY)) { > > + error_report("vfio: Warning: Error notification not supported > for the device\n"); > > This should probably just be a debug print. Okay. > > > + return; > > + } > > + if (event_notifier_init(&vdev->errfd, 0)) { > > + error_report("vfio: Warning: Unable to init event notifier for > error detection\n"); > > + return; > > + } > > + pfd = event_notifier_get_fd(&vdev->errfd); > > + qemu_set_fd_handler(pfd, vfio_errfd_handler, NULL, vdev); > > + > > + ret = ioctl(vdev->fd, VFIO_DEVICE_SET_ERRFD, pfd); > > + if (ret) { > > + error_report("vfio: Warning: Failed to setup error fd: %d\n", > ret); > > + qemu_set_fd_handler(pfd, NULL, NULL, vdev); > > + event_notifier_cleanup(&vdev->errfd); > > + } > > + return; > > +} > > static int vfio_initfn(PCIDevice *pdev) > > { > > VFIODevice *pvdev, *vdev = DO_UPCAST(VFIODevice, pdev, pdev); > > @@ -2010,6 +2064,8 @@ static int vfio_initfn(PCIDevice *pdev) > > } > > } > > > > + vfio_register_errfd(vdev); > > + > > No cleanup in exitfn?! Thanks, Missed that. Will fix. Vijay > > Alex > > > return 0; > > > > out_teardown: > > diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h > > index 4758d1b..0ca4eeb 100644 > > --- a/linux-headers/linux/vfio.h > > +++ b/linux-headers/linux/vfio.h > > @@ -147,6 +147,7 @@ struct vfio_device_info { > > __u32 flags; > > #define VFIO_DEVICE_FLAGS_RESET (1 << 0) /* Device supports reset */ > > #define VFIO_DEVICE_FLAGS_PCI (1 << 1) /* vfio-pci device */ > > +#define VFIO_DEVICE_FLAGS_AER_NOTIFY (1 << 2) /* Supports aer > notification */ > > __u32 num_regions; /* Max region index + 1 */ > > __u32 num_irqs; /* Max IRQ index + 1 */ > > }; > > @@ -288,6 +289,14 @@ struct vfio_irq_set { > > */ > > #define VFIO_DEVICE_RESET _IO(VFIO_TYPE, VFIO_BASE + 11) > > > > +/** > > + * VFIO_DEVICE_SET_ERRFD - _IO(VFIO_TYPE, VFIO_BASE + 12) > > + * > > + * Pass the eventfd to the vfio-pci driver for signalling any device > > + * error notifications > > + */ > > +#define VFIO_DEVICE_SET_ERRFD _IO(VFIO_TYPE, VFIO_BASE + 12) > > + > > /* > > * The VFIO-PCI bus driver makes use of the following fixed region and > > * IRQ index mapping. Unimplemented regions return a size of zero. > > ��.n��������+%������w��{.n�����o�^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�
