z@rocksvax.UUCP (Jim Ziobro) (12/05/85)
Revisions: 4.2BSD and 4.3BSD (Beta)
Index: /sys/vaxuba/dh.c
Problem: dm handler fails to lock out interrupts.
Repeat by: Toggle the carrier on one of the multiplexors lines. Then
watch random login processes get hangup signals. This problem
was discovered on an Emulex CS-11 with 32 lines.
Fix: Add an spl5/splx to the dm interrupt handler.
This is a fix for 4.2:
*** dh.c.ucb Fri Jul 29 10:33:35 1983
--- dh.c Wed Dec 4 22:40:35 1985
***************
*** 699,704
register struct uba_device *ui;
register struct tty *tp;
register struct dmdevice *addr;
ui = dminfo[dm];
if (ui == 0)
--- 699,705 -----
register struct uba_device *ui;
register struct tty *tp;
register struct dmdevice *addr;
+ int s;
ui = dminfo[dm];
if (ui == 0)
***************
*** 703,708
ui = dminfo[dm];
if (ui == 0)
return;
addr = (struct dmdevice *)ui->ui_addr;
if (addr->dmcsr&DM_DONE) {
if (addr->dmcsr&DM_CF) {
--- 704,713 -----
ui = dminfo[dm];
if (ui == 0)
return;
+ /*
+ If you have two dm's the second may interrupt so block it.
+ */
+ s = spl5();
addr = (struct dmdevice *)ui->ui_addr;
if (addr->dmcsr&DM_DONE) {
if (addr->dmcsr&DM_CF) {
***************
*** 731,735
}
addr->dmcsr = DM_IE|DM_SE;
}
}
#endif
--- 736,741 -----
}
addr->dmcsr = DM_IE|DM_SE;
}
+ splx(s);
}
#endif
--
//Z\\
James M. Ziobro
Ziobro.Henr@Xerox.ARPA
{rochester,amd,sunybcs,ihnp4}!rocksvax!z