Public bug reported: qemu-img incorrectly prints this warning when you use /dev/fd/<NN> to pass in file descriptors. A simple way to demonstrate this uses bash process substitution, so the following will only work if you are using bash as your shell:
$ qemu-img info <( cat /dev/null ) qemu-img: Host floppy pass-through is deprecated Support for it will be removed in a future release. qemu-img: Could not open '/dev/fd/63': Could not refresh total sector count: Illegal seek The root cause is a bug in block/raw-posix.c:floppy_probe_device() where it thinks anything starting with /dev/fd is a floppy drive, which is not the case here: http://git.qemu.org/?p=qemu.git;a=blob;f=block/raw- posix.c;h=cbe6574bf4da90a124436a40422dce3667da71e6;hb=HEAD#l2425 ** Affects: qemu Importance: Undecided Status: New -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1470536 Title: qemu-img incorrectly prints "qemu-img: Host floppy pass-through is deprecated" Status in QEMU: New Bug description: qemu-img incorrectly prints this warning when you use /dev/fd/<NN> to pass in file descriptors. A simple way to demonstrate this uses bash process substitution, so the following will only work if you are using bash as your shell: $ qemu-img info <( cat /dev/null ) qemu-img: Host floppy pass-through is deprecated Support for it will be removed in a future release. qemu-img: Could not open '/dev/fd/63': Could not refresh total sector count: Illegal seek The root cause is a bug in block/raw-posix.c:floppy_probe_device() where it thinks anything starting with /dev/fd is a floppy drive, which is not the case here: http://git.qemu.org/?p=qemu.git;a=blob;f=block/raw- posix.c;h=cbe6574bf4da90a124436a40422dce3667da71e6;hb=HEAD#l2425 To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1470536/+subscriptions