Andrew E. Mileski (
Wed, 30 Jul 1997 14:54:01 -0400 (EDT)

Is there a general effort underway to squash cli/sti pairs?
I ask because I think there should be. The code should restore
the flags if it is going to be re-entrant.

The loop driver assumes some kernel code is re-entrant, when it
definitely isn't (cli/sti pairs get executed). The bug strikes
mostly on a loaded system, so it was terribly hard to track this
bug down. Changing the code to restore the flags works fine, as
the code involved is otherwise re-entrant.

I wonder how much other code in the kernel makes assumptions about
the interrupt state.

Andrew E. Mileski