[netbsd-7] Critical issue with ffs+log

[BERTRAND Joël <joel.bertrand%systella.fr@localhost>]

	Hello,

	I have installed NetBSD 7.0 (but I have also tested NetBSD 7 from last 
cvs tree with the same constatation) on an amd64 (i7-4770).

My /etc/fstab :
legendre# cat /etc/fstab
# NetBSD /targetroot/etc/fstab
# See /usr/share/examples/fstab/ for more examples.
/dev/ld0a               /               ffs     rw,log           1 1
/dev/ld0b               none            swap    sw,dp            0 0
/dev/ld0e               /usr            ffs     rw,log           1 2
/dev/ld0f               /var            ffs     rw,log           1 2
/dev/ld0g               /home           ffs     rw,log           1 2
kernfs                  /kern           kernfs  rw
ptyfs                   /dev/pts        ptyfs   rw
procfs                  /proc           procfs  rw
/dev/cd0a               /cdrom          cd9660  ro,noauto
tmpfs                   /var/shm        tmpfs   rw,-m1777,-sram%25

	rld0 contains two disks (wd0 and wd1). Both are clean (smartctl doesn't 
return any error) and new.

	I haven't seen any data corruption without log option. With log option, 
I have to reboot one or two times each day this server to manually do 
fsck on disk.

	For example : I have tried to build kdelibs4 from sources this evening 
(with MAKE_JOBS=8). In a first time, some of generated files were 
corrupted. I suspect a race condition somewhere. Thus, I have tried to 
delete all files in build tree and I have obtained :


legendre# rm -rfv *
rm: fts_read: No such file or directory
legendre#

legendre# du
du: ./_KDE_build/kdecore/tests/CMakeFiles/kglobaltest.dir/: No such file 
or directory
du: fts_read: No such file or directory

legendre# cd ./_KDE_build/kdecore/tests/CMakeFiles/
legendre# ls
CMakeDirectoryInformation.cmake         krandomsequencetest_automoc.dir
kglobaltest.dir                         ksavefiletest.dir
kglobaltest_automoc.dir                 ksavefiletest_automoc.dir
kjobtest.dir                            kservicetest.dir
...
legendre# ls
ls: .: No such file or directory
legendre# pwd
/usr/pkgsrc/x11/kdelibs4/work/kdelibs-4.14.3/_KDE_build/kdecore/tests/CMakeFiles/kglobaltest.dir

	If I reboot in single user mode, fsck fixes ffs structure.

	Regards,

	JKB