device: 0.141
other: 0.111
vnc: 0.103
PID: 0.084
graphic: 0.068
semantic: 0.067
KVM: 0.064
boot: 0.056
debug: 0.055
socket: 0.055
files: 0.054
permissions: 0.052
performance: 0.048
network: 0.042
boot: 0.162
debug: 0.154
vnc: 0.145
PID: 0.133
device: 0.109
files: 0.068
socket: 0.063
KVM: 0.048
permissions: 0.033
network: 0.024
other: 0.022
semantic: 0.019
performance: 0.013
graphic: 0.006

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QEMU 0.12 is pretty much outdated ...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 QEMU 0.12 is pretty much outdated ...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.