device: 0.867
architecture: 0.860
peripherals: 0.850
vnc: 0.837
hypervisor: 0.789
risc-v: 0.776
VMM: 0.743
ppc: 0.739
PID: 0.730
KVM: 0.675
graphic: 0.673
TCG: 0.671
boot: 0.635
user-level: 0.605
performance: 0.602
register: 0.595
x86: 0.593
debug: 0.585
permissions: 0.573
mistranslation: 0.572
socket: 0.553
arm: 0.538
files: 0.535
semantic: 0.527
virtual: 0.519
network: 0.477
assembly: 0.401
kernel: 0.370
i386: 0.328

qemu does not pass sector size from physical devices to virtual devices

When passing a physical disk (i.e. a multipathed fcal volume in my case) with a 4k sector size as raw image to qemu (-drive file=/dev/mapper/hartebeest-sys,if=none,id=drive-virtio-disk0,boot=on,format=raw), the resulting virtual device has a sector size of 512b, rendering the partition table unusable!

QEMU 0.12 is pretty much outdated ... can you still reproduce this issue with the latest version of QEMU, or can we close this bug nowadays?

Hi,

I can’t verify it for the logical block size right away, but 
this bug still present for the physical block size in qemu-kvm 1:2.1+dfsg-1.

I will try to verify this bug with testing soon

> On 20. Mar 2017, at 23:57, Thomas Huth <email address hidden> wrote:
> 
> QEMU 0.12 is pretty much outdated ... can you still reproduce this issue
> with the latest version of QEMU, or can we close this bug nowadays?
> 
> ** Changed in: qemu
>       Status: New => Incomplete
> 
> -- 
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/877498
> 
> Title:
>  qemu does not pass sector size from physical devices to virtual
>  devices
> 
> Status in QEMU:
>  Incomplete
> 
> Bug description:
>  When passing a physical disk (i.e. a multipathed fcal volume in my
>  case) with a 4k sector size as raw image to qemu (-drive
>  file=/dev/mapper/hartebeest-sys,if=none,id=drive-virtio-
>  disk0,boot=on,format=raw), the resulting virtual device has a sector
>  size of 512b, rendering the partition table unusable.
> 
>  Versions used: QEMU 0.12.5 (qemu-kvm-0.12.5) from debian unstable
> 
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/qemu/+bug/877498/+subscriptions
> 

AVE!
  Philipp S. Tiesel / phils…
-- 
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QEMU 2.1 is also not supported anymore. Please test with the latest upstream QEMU version (2.8 ... or the latest 2.9 release candidate) - or otherwise report the bug in the bug tracker of your distribution instead.

[Expired for QEMU because there has been no activity for 60 days.]

Recent QEMU is able to do read-modify-write operations when using 512 byte logical sectors in the VM and 4K logical sectors in the host.