Re: cloning device close race?

[christos%astron.com@localhost (Christos Zoulas)]

In article <20111219033403.GA25715%panix.com@localhost>,
Thor Lancelot Simon  <tls%panix.com@localhost> wrote:
>-=-=-=-=-=-
>
>I wrote the attached test program as a benchmark for the new
>/dev/random implementation.
>
>If you run 10 or so copies at once on a multiprocessor system
>with DIAGNOSTIC, you'll see a lot of this message emitted:
>
>vrelel: missing VOP_CLOSE(): vnode @ 0xfffffe801e73cb28, flags
>(0x800030<MPSAFE,LOCKSWORK,INACTNOW>)
>       tag VT_UFS(1), type VCHR(4), usecount 2, writecount 0, holdcount 0
>       freelisthd 0x0, mount 0xffff800024235000, data 0xfffffe801de01f00 lock
>0xfffffe801e73cc38
>       tag VT_UFS, ino 46213, on dev 4, 0 flags 0x0, nlink 1
>       mode 020644, owner 0, group 0, size 0
>
>I am guessing the problem also exists with other cloning
>pseudodevices, not just the new /dev/random implementation.

Does adding:

        vn_close(nd.ni_vp, flags, l->l_cred);

just after fd_dupopen in vfs_syscalls.c help? This should be right since
the open is not associated with that vnode anymore, right?

christos