Comment 16 for bug 2060919

> I think this patch is probably not needed in 6.5, and causes the issue. How about I build
> you a test kernel with "cifs: fix flushing folio regression for 6.1 backport" reverted,
> and then we see if it fixes things?

Yep, fantastic. I can reproduce this problem anytime so I can test it.

> If you can help me make a reproducer, that would be great. I can test myself then.

Here is some info from a faulty system. Hope it helps:

***** fstab mount:
//192.168.1.10/FPGNAS /mnt/FPGNAS_CIFS cifs _netdev,x-systemd.requires=network-online.target,async,nosuid,nodev,noexec,iocharset=utf8,file_mode=0640,dir_mode=0750,uid=1026,gid=100,credentials=/etc/.cifspwd,rw 0 0

***** mount info:
//192.168.1.10/FPGNAS on /mnt/FPGNAS_CIFS type cifs (rw,nosuid,nodev,noexec,relatime,vers=3.1.1,cache=strict,username=fprietog,uid=1026,noforceuid,gid=100,noforcegid,addr=192.168.1.10,file_mode=0640,dir_mode=0750,iocharset=utf8,soft,nounix,serverino,mapposix,rsize=4194304,wsize=4194304,bsize=1048576,echo_interval=60,actimeo=1,closetimeo=1,_netdev,x-systemd.requires=network-online.target)

***** cp from a file to a file both in same share:
# cd /mnt/FPGNAS_CIFS/tmp
/mnt/FPGNAS_CIFS/tmp# touch sample1.txt
/mnt/FPGNAS_CIFS/tmp# cp sample1.txt sample2.txt
Terminado (killed)

After that error the CIFS mount become unusable as any operation just hangs.

***** The remote cifs server is a Synology DS213j NAS. Samba version is:
# smbd -V
Version 4.15.9
Synology Build 42934, Jul 5 2023 16:52:06

Please, let me know if I can give you any other info that helps to solve the problem.