device: 0.864
performance: 0.842
files: 0.829
graphic: 0.796
ppc: 0.690
network: 0.682
architecture: 0.625
semantic: 0.612
user-level: 0.601
mistranslation: 0.596
permissions: 0.590
vnc: 0.574
VMM: 0.551
peripherals: 0.530
hypervisor: 0.524
register: 0.513
x86: 0.505
socket: 0.497
kernel: 0.497
i386: 0.479
PID: 0.456
risc-v: 0.452
virtual: 0.433
debug: 0.416
assembly: 0.401
boot: 0.399
TCG: 0.379
arm: 0.337
KVM: 0.315

NVME fails on big writes

NVME Compliance test 8:3.3.0 tries to write and read back big chunks of pages. Currently, on the latest QEMU operation of size 1024 blocks will fail when device is backed by a file.

NVME specification has several types of data transfers from guests, one of the is the PRP list (Physical Region Page List). PRP is a list of entries pointing to pages to be written. The list it self resides in a single or multiple pages.

NVME device maps the PRP list into QEMUSGList which will be me mapped into linux IO vectors. Finally, when the file driver will write the changes, it uses the posix pwritev, which fails if the number of vectors exceeds the maximum.


NVME Compliance - https://github.com/nvmecompliance/tnvme/wiki

The QEMU project is currently considering to move its bug tracking to another system. For this we need to know which bugs are still valid and which could be closed already. Thus we are setting older bugs to "Incomplete" now.
If you still think this bug report here is valid, then please switch the state back to "New" within the next 60 days, otherwise this report will be marked as "Expired". Or mark it as "Fix Released" if the problem has been solved with a newer version of QEMU already. Thank you and sorry for the inconvenience.

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