diff options
| author | Michael Shalayeff <mickey@cvs.openbsd.org> | 1997-10-12 21:01:02 +0000 |
|---|---|---|
| committer | Michael Shalayeff <mickey@cvs.openbsd.org> | 1997-10-12 21:01:02 +0000 |
| commit | 345757705da17aafac67f3c66fb9ea2ff7eb60e8 (patch) | |
| tree | d876e31865e29f72cadd4d81805147c9bcc562d1 /sys/arch | |
| parent | 08eacca3df59e33e7e2f6e64e9b847cfb12441a4 (diff) | |
safe memprobe; preserve memory contents
Diffstat (limited to 'sys/arch')
| -rw-r--r-- | sys/arch/i386/stand/libsa/memprobe.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/sys/arch/i386/stand/libsa/memprobe.c b/sys/arch/i386/stand/libsa/memprobe.c index bb3d5856d8f..180d742f4dc 100644 --- a/sys/arch/i386/stand/libsa/memprobe.c +++ b/sys/arch/i386/stand/libsa/memprobe.c @@ -1,4 +1,4 @@ -/* $OpenBSD: memprobe.c,v 1.13 1997/10/12 20:14:27 mickey Exp $ */ +/* $OpenBSD: memprobe.c,v 1.14 1997/10/12 21:01:01 mickey Exp $ */ /* * Copyright (c) 1997 Tobias Weingartner @@ -82,33 +82,43 @@ static int addrprobe(kloc) u_int kloc; { - __volatile u_int *loc, i; + __volatile u_int *loc; static const u_int pat[] = { 0x00000000, 0xFFFFFFFF, 0x01010101, 0x10101010, 0x55555555, 0xCCCCCCCC }; + register u_int i, ret = 0; + u_int save[NENTS(pat)]; /* Get location */ loc = (int *)(kloc * 1024); + save[0] = *loc; /* Probe address */ for(i = 0; i < NENTS(pat); i++){ *loc = pat[i]; if(*loc != pat[i]) - return (1); + ret++; + } + *loc = save[0]; + + if (!ret) { + /* Write address */ + for(i = 0; i < NENTS(pat); i++) { + save[i] = loc[i]; + loc[i] = pat[i]; + } + + /* Read address */ + for(i = 0; i < NENTS(pat); i++) { + if(loc[i] != pat[i]) + ret++; + loc[i] = save[i]; + } } - /* Write address */ - for(i = 0; i < NENTS(pat); i++) - loc[i] = pat[i]; - - /* Read address */ - for(i = 0; i < NENTS(pat); i++) - if(loc[i] != pat[i]) - return (1); - - return (0); + return ret; } |