Re: Surprising fact about STREAMS service modules

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Article #935

#935

From: Steven M. Bellovin
Date: Sun, 25 Dec 1988 20:31

7 lines
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A persistent bug source, in many versions on the UNIX system, is that
splN() calls, other than splx(), unconditionally set the interrupt
level to the indicated value, rather than *raising* it to that value.
It is almost never correct to lower an interrupt level, except via
splx() or spl0().  Sun has gotten some of those right; the symbolic
spl() calls (splimp(), etc.) check the current level before raising it.
4.3bsd is wrong; I haven't been able to check 4.3 Tahoe yet.

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Message-ID: <11047@ulysses.homer.nj.att.com>

Path: arc1-ca.pugleaf.net!utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!ukma!gatech!ulysses!smb

References: <4385@hcr.UUCP> <313@taniwha.UUCP>

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Path: arc1-ca.pugleaf.net!utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!ukma!gatech!ulysses!smb
From: smb@ulysses.homer.nj.att.com (Steven M. Bellovin)
Newsgroups: comp.bugs.sys5,comp.unix.wizards
Subject: Re: Surprising fact about STREAMS service modules
Message-ID: <11047@ulysses.homer.nj.att.com>
Date: 25 Dec 88 20:31:18 GMT
References: <4385@hcr.UUCP> <313@taniwha.UUCP>
Organization: AT&T Bell Laboratories, Murray Hill
Lines: 7

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