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Added a check/panic for vm_map_find failing to find space for the page

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tables/u-pages when forking. This is a "can't happen" case. :-)
This commit is contained in:
David Greenman 1996-01-29 12:10:30 +00:00
parent 07bbd7f1bb
commit 2c68345ab4
1 changed files with 7 additions and 5 deletions
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12
sys/vm/vm_glue.c
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@ -59,7 +59,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_glue.c,v 1.36 1996/01/19 03:59:46 dyson Exp $
* $Id: vm_glue.c,v 1.37 1996/01/25 07:15:40 phk Exp $
*/
#include "opt_sysvipc.h"
@ -217,7 +217,7 @@ vm_fork(p1, p2, isvfork)
register struct user *up;
vm_offset_t addr, ptaddr, ptpa;
int error, i;
vm_map_t vp;
vm_map_t map;
pmap_t pvp;
vm_page_t stkm;
@ -246,12 +246,14 @@ vm_fork(p1, p2, isvfork)
addr = (vm_offset_t) kstack;
vp = &p2->p_vmspace->vm_map;
map = &p2->p_vmspace->vm_map;
pvp = &p2->p_vmspace->vm_pmap;
/* get new pagetables and kernel stack */
(void) vm_map_find(vp, NULL, 0, &addr, UPT_MAX_ADDRESS - addr, FALSE,
error = vm_map_find(map, NULL, 0, &addr, UPT_MAX_ADDRESS - addr, FALSE,
VM_PROT_ALL, VM_PROT_ALL, 0);
if (error != KERN_SUCCESS)
panic("vm_fork: vm_map_find failed, addr=0x%x, error=%d", addr, error);
/* get a kernel virtual address for the UPAGES for this proc */
up = (struct user *) kmem_alloc_pageable(u_map, UPAGES * PAGE_SIZE);
@ -262,7 +264,7 @@ vm_fork(p1, p2, isvfork)
UPAGES);
ptaddr = trunc_page((u_int) vtopte(kstack));
(void) vm_fault(vp, ptaddr, VM_PROT_READ|VM_PROT_WRITE, FALSE);
(void) vm_fault(map, ptaddr, VM_PROT_READ|VM_PROT_WRITE, FALSE);
ptpa = pmap_extract(pvp, ptaddr);
if (ptpa == 0) {
panic("vm_fork: no pte for UPAGES");