diff options
| author | dyson <dyson@FreeBSD.org> | 1996-03-13 00:39:45 +0000 |
|---|---|---|
| committer | dyson <dyson@FreeBSD.org> | 1996-03-13 00:39:45 +0000 |
| commit | 665e2fe6cf04ae69ecb9a21ec49c4194aec40f15 (patch) | |
| tree | 03cc64dd9dfe9a8c1ade647005bfbd57d9114cad /sys/amd64 | |
| parent | 788abb32883136336db17e5fa31912675c701682 (diff) | |
| download | FreeBSD-src-665e2fe6cf04ae69ecb9a21ec49c4194aec40f15.zip FreeBSD-src-665e2fe6cf04ae69ecb9a21ec49c4194aec40f15.tar.gz | |
Make sure that we pmap_update AFTER modifying the page table entries.
The P6 can do a serious job of reordering code, and our stuff could
execute incorrectly.
Diffstat (limited to 'sys/amd64')
| -rw-r--r-- | sys/amd64/amd64/pmap.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c index 879b69f..420b86a 100644 --- a/sys/amd64/amd64/pmap.c +++ b/sys/amd64/amd64/pmap.c @@ -39,7 +39,7 @@ * SUCH DAMAGE. * * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91 - * $Id: pmap.c,v 1.79 1996/03/10 23:06:00 dyson Exp $ + * $Id: pmap.c,v 1.80 1996/03/11 05:55:56 hsu Exp $ */ /* @@ -1457,9 +1457,9 @@ validate: * to update the pte. */ if ((origpte & ~(PG_M|PG_U)) != newpte) { + *pte = (pt_entry_t) newpte; if (origpte) pmap_update_1pg(va); - *pte = (pt_entry_t) newpte; } if (origpte == 0) { @@ -1493,9 +1493,9 @@ pmap_qenter(va, m, count) pt_entry_t npte = (pt_entry_t) ((int) (VM_PAGE_TO_PHYS(m[i]) | PG_RW | PG_V)); pt_entry_t opte; pte = vtopte(tva); - if ((opte = *pte) && (opte != npte)) - pmap_update_1pg(tva); + opte = *pte; *pte = npte; + if (opte) pmap_update_1pg(tva); } } /* @@ -1529,13 +1529,13 @@ pmap_kenter(va, pa) register vm_offset_t pa; { register pt_entry_t *pte; - pt_entry_t npte; + pt_entry_t npte, opte; npte = (pt_entry_t) ((int) (pa | PG_RW | PG_V)); pte = vtopte(va); - if (*pte) - pmap_update_1pg(va); + opte = *pte; *pte = npte; + if (opte) pmap_update_1pg(va); } /* |
