wls@astrovax.UUCP (William L. Sebok) (03/06/84)
Index: /sys/vax/machdep.c 4.2BSD
Description:
In memerr() in /sys/vax/machdep.c no test is ever done to check
whether memory errors on a VAX 750 are correctible or not. Thus
strange panics and such may occur with no indication on the console
that there was a hard error.
The fix below fixes the problem for a VAX 750. I suspect that the
same problem is also present in the VAX 780 and 730 support code, as
I have not seen any tests for the uncorrectable memory error condition.
This bug was also present in 4.1.
Repeat-By:
Get yourself a bad memory board with hard errors. The system may do
all sorts of strange things because of memory errors yet only
"soft ecc" messages will appear on the console.
Fix:
Here are the diffs to /sys/vax/machdep.c. The line numbers of the new
machdep.c may vary as there have been other fixes necessary.
*** machdep.c.ORIG Tue Feb 28 11:27:04 1984
--- machdep.c. Mon Mar 5 15:30:39 1984
***************
*** 481,488
if (M750_ERR(mcr)) {
struct mcr amcr;
amcr.mc_reg[0] = mcr->mc_reg[0];
! printf("mcr%d: soft ecc addr %x syn %x\n",
! m, M750_ADDR(&amcr), M750_SYN(&amcr));
M750_INH(mcr);
}
break;
--- 481,497 -----
if (M750_ERR(mcr)) {
struct mcr amcr;
amcr.mc_reg[0] = mcr->mc_reg[0];
! /*
! * modified to distinguish hard and soft errors
! * (W. Sebok astrovax!wls 3/7/83)
! */
! if (M750_ERR(mcr)&M750_UNCORR) {
! printf("mcr%d: hard error",m);
! } else {
! printf("mcr%d: soft ecc",m);
! }
! printf(" addr %x syn %x\n",
! M750_ADDR(&amcr), M750_SYN(&mcr));
M750_INH(mcr);
}
break;
***************
--
Bill Sebok Princeton University, Astrophysics
{allegra,akgua,burl,cbosgd,decvax,ihnp4,kpno,princeton,vax135}!astrovax!wls