Bug 617271
| Summary: | RHEL6 qemu-kvm guest gets partitioned at sector 63 | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Eric Sandeen <esandeen> |
| Component: | qemu-kvm | Assignee: | chellwig <chellwig> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | medium | Docs Contact: | |
| Priority: | low | ||
| Version: | 6.0 | CC: | bcao, chellwig, ddumas, hdegoede, llim, mkenneth, rwheeler, tburke, virt-maint, yanwang |
| Target Milestone: | rc | Keywords: | RHELNAK |
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | qemu-kvm-0.12.1.2-2.102.el6 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2010-11-10 21:26:48 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 519834 | ||
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Description
Eric Sandeen
2010-07-22 16:06:29 UTC
This issue has been proposed when we are only considering blocker issues in the current Red Hat Enterprise Linux release. ** If you would still like this issue considered for the current release, ask your support representative to file as a blocker on your behalf. Otherwise ask that it be considered for the next Red Hat Enterprise Linux release. ** (TBH I don't know where this bug belongs, maybe it's parted, but had to start somewhere. Also this may be a blocker, it has the potential to really clobber guest performance I think) There are bugs everywhere. qemu should not advertisze an opt_io_size. the kernel should not corrupt data for unaligned aio. But parted also really shouldn't do things against the stated consensus and never ever should move it's alignment below the 1MB threshold. Hi, (In reply to comment #3) > There are bugs everywhere. qemu should not advertisze an opt_io_size. the > kernel should not corrupt data for unaligned aio. But parted also really > shouldn't do things against the stated consensus and never ever should move > it's alignment below the 1MB threshold. The last time this was discussed the conclusion was that parted would default to 1 MiB alignment (which it does), and that it would honer alignment offset and optimum io size (with a fall back to minimum io size) when they are present. This is exactly what parted is doing. Not moving the alignment below a 1 MiB threshold was never discussed before, and I see no reason for this (actually when 4k physical 512 byte logical sector disks are jumpered for XP compatibility doing so is a bad idea). Regards, Hans (the parted maintainer) Will the right thing happen if we fix qemu not to advertise an optimal_io_size? (In reply to comment #5) > Will the right thing happen if we fix qemu not to advertise an optimal_io_size? If there is no optimal_io_size and no alignment_offset and minimal_io_size is a power of 2, then parted will use its default alignment of 1MiB, so yes. Reproduced in qemu-kvm-0.12.1.2-2.99.el6 Verified in qemu-kvm-0.12.1.2-2.104.el6. Steps : 1.Start VM: CLI:/usr/libexec/qemu-kvm -M rhel6.0.0 -cpu qemu64,+sse2,+x2apic -enable-kvm -m 8G -smp 8,sockets=8,cores=1,threads=1 -name RHEL6_64 -uuid `uuidgen` -nodefconfig -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/RHEL6.monitor,server,nowait -mon chardev=monitor,mode=control -rtc base=utc -boot c -drive file=/mnt/RHEL6.0.raw,if=none,id=drive-ide0-0-0,boot=on,format=raw,cache=none -device virtio-blk-pci,drive=drive-ide0-0-0,id=ide0-0-0 -netdev tap,id=hostnet0,vhost=on -device virtio-net-pci,netdev=hostnet0,id=net0,mac=52:54:20:8d:62:99,bus=pci.0,addr=0x5 -chardev pty,id=serial0 -device isa-serial,chardev=serial0 -usb -device usb-tablet,id=input0 -spice port=5931,disable-ticketing -vga std -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 2.in the guest #cat /sys/block/vda/queue/optimal_io_size. Actual Results: 0 The bug has already been fixed. Change status to VERIFIED. Red Hat Enterprise Linux 6.0 is now available and should resolve the problem described in this bug report. This report is therefore being closed with a resolution of CURRENTRELEASE. You may reopen this bug report if the solution does not work for you. |