An virtfs(9p) backend error occurs when running python when SMP=1.

[ken4647]

when running cmd make A=apps/c/python3 ARCH=aarch64 V9P=y NET=y MUSL=y LOG=off run :

qemu-system-aarch64: Failed to decode VirtFS request type 50

and type 50 means fsync.

The backend error is like this:

[ken4647]

in 9P2000.L , the format of tfsync is like below:

fsync - flush any cached data to disk

size[4] Tfsync tag[2] fid[4]
size[4] Rfsync tag[2]

fsync tells the server to flush any cached data associated with fid, previously opened with lopen.

However, in 9p client on linux, it is implemented like this:

size[4] Tfsync tag[2] fid[4] datasync[4]

This may be due to some problems or requirements that have caused the operation specifications of 9p's fsync to change, so our interface also needs to be patched accordingly.

[ken4647]

fixed in #133 .