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Remove a "not strictly correct" (and panic-inducing) workaround for a bug

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which doesn't seem to exist.

PR:		kern/141328
MFC after:	3 days
This commit is contained in:
Colin Percival 2010-12-28 14:36:32 +00:00
parent 45b71cd16e
commit 4a416f8375
1 changed files with 2 additions and 15 deletions
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17
sys/i386/xen/pmap.c
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@ -2225,27 +2225,14 @@ pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va, vm_page_t *free)
if (oldpte & PG_G)
pmap_invalidate_page(kernel_pmap, va);
pmap->pm_stats.resident_count -= 1;
/*
* XXX This is not strictly correctly, but somewhere along the line
* we are losing the managed bit on some pages. It is unclear to me
* why, but I think the most likely explanation is that xen's writable
* page table implementation doesn't respect the unused bits.
*/
if ((oldpte & PG_MANAGED) || ((oldpte & PG_V) && (va < VM_MAXUSER_ADDRESS))
) {
if (oldpte & PG_MANAGED) {
m = PHYS_TO_VM_PAGE(xpmap_mtop(oldpte) & PG_FRAME);
if (!(oldpte & PG_MANAGED))
printf("va=0x%x is unmanaged :-( pte=0x%llx\n", va, oldpte);
if ((oldpte & (PG_M | PG_RW)) == (PG_M | PG_RW))
vm_page_dirty(m);
if (oldpte & PG_A)
vm_page_flag_set(m, PG_REFERENCED);
pmap_remove_entry(pmap, m, va);
} else if ((va < VM_MAXUSER_ADDRESS) && (oldpte & PG_V))
printf("va=0x%x is unmanaged :-( pte=0x%llx\n", va, oldpte);
}
return (pmap_unuse_pt(pmap, va, free));
}