diff options
| author | Raphael Norwitz | 2022-01-17 05:12:35 +0100 |
|---|---|---|
| committer | Michael S. Tsirkin | 2022-02-04 15:07:43 +0100 |
| commit | 4fafedc9daaf7d7d5ad36d8925bdddd6da5ed8c2 (patch) | |
| tree | c37fbea6c057f80d36bed7ae244f5ef19a92a906 /subprojects | |
| parent | libvhost-user: prevent over-running max RAM slots (diff) | |
| download | qemu-4fafedc9daaf7d7d5ad36d8925bdddd6da5ed8c2.tar.gz qemu-4fafedc9daaf7d7d5ad36d8925bdddd6da5ed8c2.tar.xz qemu-4fafedc9daaf7d7d5ad36d8925bdddd6da5ed8c2.zip | |
libvhost-user: handle removal of identical regions
Today if QEMU (or any other VMM) has sent multiple copies of the same
region to a libvhost-user based backend and then attempts to remove the
region, only one instance of the region will be removed, leaving stale
copies of the region in dev->regions[].
This change resolves this by having vu_rem_mem_reg() iterate through all
regions in dev->regions[] and delete all matching regions.
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20220117041050.19718-7-raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Diffstat (limited to 'subprojects')
| -rw-r--r-- | subprojects/libvhost-user/libvhost-user.c | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index 2a1fa00a44..0ee43b8e93 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -821,6 +821,7 @@ static bool vu_rem_mem_reg(VuDev *dev, VhostUserMsg *vmsg) { VhostUserMemoryRegion m = vmsg->payload.memreg.region, *msg_region = &m; int i; + bool found = false; if (vmsg->fd_num != 1) { vmsg_close_fds(vmsg); @@ -856,21 +857,24 @@ vu_rem_mem_reg(VuDev *dev, VhostUserMsg *vmsg) { munmap(m, r->size + r->mmap_offset); } - break; + /* + * Shift all affected entries by 1 to close the hole at index i and + * zero out the last entry. + */ + memmove(dev->regions + i, dev->regions + i + 1, + sizeof(VuDevRegion) * (dev->nregions - i - 1)); + memset(dev->regions + dev->nregions - 1, 0, sizeof(VuDevRegion)); + DPRINT("Successfully removed a region\n"); + dev->nregions--; + i--; + + found = true; + + /* Continue the search for eventual duplicates. */ } } - if (i < dev->nregions) { - /* - * Shift all affected entries by 1 to close the hole at index i and - * zero out the last entry. - */ - memmove(dev->regions + i, dev->regions + i + 1, - sizeof(VuDevRegion) * (dev->nregions - i - 1)); - memset(dev->regions + dev->nregions - 1, 0, - sizeof(VuDevRegion)); - DPRINT("Successfully removed a region\n"); - dev->nregions--; + if (found) { vmsg_set_reply_u64(vmsg, 0); } else { vu_panic(dev, "Specified region not found\n"); |