Red Hat Bugzilla – Bug 26293
The shm filesystem should be mounted
Last modified: 2014-03-16 22:18:41 EDT
glibc is looking for an instance of shm fs/swapfs for posix shared memory.
The SAP application server expects it at /dev/shm
The response from the kernel group is that this should *not* be mounted
automatically at boot; feel free to mount it if you need it.
Oh, I am suprised: I made the filesystem, worked with the glibc group that
they use it for POSIX shm, the kernel docs say also it should be mounted, but
you think it is not needed :-(
I believe there are concerns about it
a) working correctly
b) being used for simple DoS attacks
At a) You rely on SYSV shm in some applications? They use the same fs but
kern_mounted. I am pretty sure it works better than any shm implementation we
had in the 2.x timeframe.
At b) You could use the mount option nr_blocks, or on an -ac kernel the mount
otion size to protect against that.