cvs commit: src/sys/kern kern_intr.c

[Matthew Dillon]

dillon      2005/10/25 18:16:04 PDT

DragonFly src repository

  Modified files:
    sys/kern             kern_intr.c 
  Log:
  Fix a long-standing bug in the livelock code.  An interrupt thread normally
  unmasks the hardware interrupt source when it is through.  However, if a
  livelock occurs the interrupt thread may be polled long after a device has
  terminated operations and torn down its interrupt.  To solve this problem,
  only unmask the hardware interrupt if the IRQ still has device handlers
  installed.  This fixes a weird problem with the parallel port driver
  (which installs and tears-down IRQ 7 on each write() for some unfathomable
  reason).
  
  Revision  Changes    Path
  1.29      +7 -1      src/sys/kern/kern_intr.c


http://www.dragonflybsd.org/cvsweb/src/sys/kern/kern_intr.c.diff?r1=1.28&r2=1.29&f=u