Interrupted system call

["R. Diez" <rdiez@neanderfunk.de>]

Hi all:

First of all, many thanks for Git.

After a 3-month pause, I recently updated my Ubuntu 18.04.4. I am using a PPA to keep Git more up to date, so I have now "git version 2.27.0".

I am now getting this kind of errors:

fatal: failed to read object cf965547a433493caa80e84d7a2b78b32a26ee35: Interrupted system call

error: unable to mmap /home/rdiez/[blah blah]/SrcRepo.git/objects/2e/f96ffba4c0d60f36c8779758f82752be380689: Interrupted system call

I am using a mount point for a network share. Keep in mind that Git thinks it is working on a local directory, so there should be no sockets 
or non-blocking I/O involved.

The problem is probably caused by using SMB to connect to an outdated Windows server. It has been working for years, but at some point in 
time it is bound to fail. The Linux kernel itself seems to introduce bugs in the SMB/CIFS code every now and then.

Nevertheless, I am surprised to get such an "Interrupted system call" from Git. A long time ago I learnt that it is OK for many syscalls to 
get interrupted, so you have to loop around them. See here for more information:

http://250bpm.com/blog:12

As a result, users should never actually get an "Interrupted system call" error from any software, at least when no sockets or non-blocking 
I/O is involved.

How can I pin-point this problem? I would like to know where Git is encountering this error, so that I can troubleshoot it, and maybe report 
yet another bug to the Linux SMB/CIFS maintainer.

Thanks in advance,
   rdiez