qemu-e2k/hw/virtio
David Hildenbrand 364eff6885 virtio-mem: fix division by zero in virtio_mem_activate_memslots_to_plug()
When running with "dynamic-memslots=off", we enter
virtio_mem_activate_memslots_to_plug() to return immediately again
because "vmem->dynamic_memslots == false". However, the compiler might
not optimize out calculating start_idx+end_idx, where we divide by
vmem->memslot_size. In such a configuration, the memslot size is 0 and
we'll get a division by zero:

    (qemu) qom-set vmem0 requested-size 3G
    (qemu) q35.sh: line 38: 622940 Floating point exception(core dumped)

The same is true for virtio_mem_deactivate_unplugged_memslots(), however
we never really reach that code without a prior
virtio_mem_activate_memslots_to_plug() call.

Let's fix it by simply calling these functions only with
"dynamic-memslots=on".

This was found when using a debug build of QEMU.

Message-ID: <20231023111341.219317-1-david@redhat.com>
Reprted-by: Mario Casquero <mcasquer@redhat.com>
Fixes: 177f9b1ee4 ("virtio-mem: Expose device memory dynamically via multiple memslots if enabled")
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
2023-11-13 09:35:44 +01:00
..
Kconfig virtio-md-pci: New parent type for virtio-mem-pci and virtio-pmem-pci 2023-07-12 09:27:25 +02:00
meson.build virtio: add vhost-user-base and a generic vhost-user-device 2023-10-04 04:54:04 -04:00
trace-events virtio-iommu: Consolidate host reserved regions and property set ones 2023-11-03 09:20:31 +01:00
trace.h
vdpa-dev-pci.c vdpa: add vdpa-dev-pci support 2022-12-21 06:35:28 -05:00
vdpa-dev.c vdpa: move vhost_vdpa_set_vring_ready to the caller 2023-10-04 04:54:21 -04:00
vhost-backend.c vhost-backend: remove vhost_kernel_reset_device() 2023-10-22 05:18:16 -04:00
vhost-iova-tree.c util: accept iova_tree_remove_parameter by value 2022-09-02 10:22:39 +08:00
vhost-iova-tree.h util: accept iova_tree_remove_parameter by value 2022-09-02 10:22:39 +08:00
vhost-scsi-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-shadow-virtqueue.c vhost: Expose vhost_svq_available_slots() 2023-10-18 10:41:50 -04:00
vhost-shadow-virtqueue.h vhost: Expose vhost_svq_available_slots() 2023-10-18 10:41:50 -04:00
vhost-stub.c vhost: Add vhost_get_max_memslots() 2023-10-12 14:15:22 +02:00
vhost-user-blk-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-device-pci.c virtio: add vhost-user-base and a generic vhost-user-device 2023-10-04 04:54:04 -04:00
vhost-user-device.c hw/virtio: add config support to vhost-user-device 2023-10-04 04:54:05 -04:00
vhost-user-fs-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-fs.c vhost-user-fs: Implement internal migration 2023-11-07 03:39:10 -05:00
vhost-user-gpio-pci.c hw/virtio: add vhost-user-gpio-pci boilerplate 2022-10-07 09:41:51 -04:00
vhost-user-gpio.c vhost-user: fix lost reconnect 2023-10-22 05:18:17 -04:00
vhost-user-i2c-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-i2c.c virtio: i2c: Check notifier helpers for VIRTIO_CONFIG_IRQ_IDX 2023-04-24 22:56:55 -04:00
vhost-user-input-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-rng-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-rng.c vhost-user-rng: Back up vqs before cleaning up vhost_dev 2023-03-02 03:10:47 -05:00
vhost-user-scmi-pci.c hw/virtio: Add vhost-user-scmi-pci boilerplate 2023-07-10 16:17:08 -04:00
vhost-user-scmi.c hw/virtio: Add a protection against duplicate vu_scmi_stop calls 2023-08-03 16:06:49 -04:00
vhost-user-scsi-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-vsock-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-user-vsock.c hw/virtio: introduce virtio_device_should_start 2022-11-07 14:08:18 -05:00
vhost-user.c vhost-user: Interface for migration state transfer 2023-11-07 03:39:10 -05:00
vhost-vdpa.c vhost: Remove vhost_backend_can_merge() callback 2023-10-12 14:15:21 +02:00
vhost-vsock-common.c hw/virtio: fix typo in VIRTIO_CONFIG_IRQ_IDX comments 2023-07-10 18:59:32 -04:00
vhost-vsock-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
vhost-vsock.c hw/virtio: introduce virtio_device_should_start 2022-11-07 14:08:18 -05:00
vhost.c vhost: Add high-level state save/load functions 2023-11-07 03:39:10 -05:00
virtio-9p-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-balloon-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-balloon.c hw: replace most qemu_bh_new calls with qemu_bh_new_guarded 2023-04-28 11:31:54 +02:00
virtio-blk-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-bus.c virtio: stop ioeventfd on reset 2022-06-14 16:50:30 +02:00
virtio-config-io.c hw/virtio: Extract config read/write accessors to virtio-config-io.c 2022-12-21 07:32:24 -05:00
virtio-crypto-pci.c
virtio-crypto.c hw/other: spelling fixes 2023-09-21 11:31:16 +03:00
virtio-hmp-cmds.c virtio: Move HMP commands from monitor/ to hw/virtio/ 2023-02-04 07:56:54 +01:00
virtio-input-host-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-input-pci.c virtio-input-pci: add virtio-multitouch-pci 2023-05-28 13:08:25 +04:00
virtio-iommu-pci.c virtio-iommu: Rename reserved_regions into prop_resv_regions 2023-11-03 09:20:31 +01:00
virtio-iommu.c hw/pci: modify pci_setup_iommu() to set PCIIOMMUOps 2023-11-03 09:20:31 +01:00
virtio-md-pci.c virtio-md-pci: Support unplug requests for compatible devices 2023-07-12 09:27:30 +02:00
virtio-mem-pci.c virtio-mem: Expose device memory dynamically via multiple memslots if enabled 2023-10-12 14:15:22 +02:00
virtio-mem-pci.h virtio-md-pci: New parent type for virtio-mem-pci and virtio-pmem-pci 2023-07-12 09:27:25 +02:00
virtio-mem.c virtio-mem: fix division by zero in virtio_mem_activate_memslots_to_plug() 2023-11-13 09:35:44 +01:00
virtio-mmio.c kvm: require KVM_CAP_IOEVENTFD and KVM_CAP_IOEVENTFD_ANY_LENGTH 2023-10-25 17:35:15 +02:00
virtio-net-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-pci.c kvm: require KVM_CAP_IOEVENTFD and KVM_CAP_IOEVENTFD_ANY_LENGTH 2023-10-25 17:35:15 +02:00
virtio-pmem-pci.c virtio-md-pci: New parent type for virtio-mem-pci and virtio-pmem-pci 2023-07-12 09:27:25 +02:00
virtio-pmem-pci.h virtio-md-pci: New parent type for virtio-mem-pci and virtio-pmem-pci 2023-07-12 09:27:25 +02:00
virtio-pmem.c Revert "hw/virtio/virtio-pmem: Replace impossible check by assertion" 2023-11-06 13:53:59 +01:00
virtio-qmp.c vhost-user: move VhostUserProtocolFeature definition to header file 2023-10-04 04:54:28 -04:00
virtio-qmp.h qmp: remove virtio_list, search QOM tree instead 2023-10-04 04:54:24 -04:00
virtio-rng-pci.c virtio-rng-pci: Allow setting nvectors, so we can use MSI-X 2022-11-07 13:12:20 -05:00
virtio-rng.c virtio: drop name parameter for virtio_init() 2022-05-16 04:38:40 -04:00
virtio-scsi-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-serial-pci.c hw/virtio: move virtio-pci.h into shared include space 2022-05-16 04:38:40 -04:00
virtio-stub.c qmp: add QMP command x-query-virtio-queue-element 2022-10-09 16:38:45 -04:00
virtio.c virtio: use defer_call() in virtio_irqfd_notify() 2023-10-31 15:42:14 +01:00