Commit 1606e4cf authored by Eric Blake's avatar Eric Blake Committed by Max Reitz
Browse files

throttle: Remove block from group on hot-unplug 

When a block device that is part of a throttle group is hot-unplugged,
we forgot to remove it from the throttle group. This leaves stale
memory around, and causes an easily reproducible crash:

$ ./x86_64-softmmu/qemu-system-x86_64 -nodefaults -nographic -qmp stdio \
-device virtio-scsi-pci,bus=pci.0 -drive \
id=drive_image2,if=none,format=raw,file=file2,bps=512000,iops=100,group=foo \
-device scsi-hd,id=image2,drive=drive_image2 -drive \
id=drive_image3,if=none,format=raw,file=file3,bps=512000,iops=100,group=foo \
-device scsi-hd,id=image3,drive=drive_image3
{'execute':'qmp_capabilities'}
{'execute':'device_del','arguments':{'id':'image3'}}
{'execute':'system_reset'}

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1428810



Suggested-by: default avatarAlberto Garcia <berto@igalia.com>
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
Message-id: 20170406190847.29347-1-eblake@redhat.com
Reviewed-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent 7a9e5119

block/block-backend.c

+3 −0
Original line number Diff line number Diff line
@@ -231,6 +231,9 @@ static void blk_delete(BlockBackend *blk) 
    assert(!blk->refcnt);

    assert(!blk->name);

    assert(!blk->dev);

    if (blk->public.throttle_state) {

        blk_io_limits_disable(blk);

    }

    if (blk->root) {

        blk_remove_bs(blk);

    }