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Propagate attribute changes during demotion.

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After r349117 and r349122, some mapping attribute changes do not trigger
superpage demotion. However, pmap_demote_l2() was not updated to ensure
that the replacement L3 entries carry any attribute changes that
occurred since promotion.

Reported and tested by:	manu
Reviewed by:	alc
MFC after:	1 week
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D20965
This commit is contained in:
Mark Johnston 2019-07-16 14:40:49 +00:00
parent 1f69b3fb55
commit 9da9cb48e9
1 changed files with 16 additions and 16 deletions
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32
sys/arm64/arm64/pmap.c
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@ -5309,6 +5309,17 @@ pmap_demote_l1(pmap_t pmap, pt_entry_t *l1, vm_offset_t va)
return (l2);
}
static void
pmap_fill_l3(pt_entry_t *firstl3, pt_entry_t newl3)
{
pt_entry_t *l3;
for (l3 = firstl3; l3 - firstl3 < Ln_ENTRIES; l3++) {
*l3 = newl3;
newl3 += L3_SIZE;
}
}
static void
pmap_demote_l2_abort(pmap_t pmap, vm_offset_t va, pt_entry_t *l2,
struct rwlock **lockp)
@ -5330,9 +5341,8 @@ pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2, vm_offset_t va,
{
pt_entry_t *l3, newl3, oldl2;
vm_offset_t tmpl2;
vm_paddr_t l3phys, phys;
vm_paddr_t l3phys;
vm_page_t ml3;
int i;
PMAP_LOCK_ASSERT(pmap, MA_OWNED);
l3 = NULL;
@ -5406,27 +5416,17 @@ pmap_demote_l2_locked(pmap_t pmap, pt_entry_t *l2, vm_offset_t va,
}
l3phys = VM_PAGE_TO_PHYS(ml3);
l3 = (pt_entry_t *)PHYS_TO_DMAP(l3phys);
/* Address the range points at */
phys = oldl2 & ~ATTR_MASK;
/* The attributed from the old l2 table to be copied */
newl3 = (oldl2 & (ATTR_MASK & ~ATTR_DESCR_MASK)) | L3_PAGE;
newl3 = (oldl2 & ~ATTR_DESCR_MASK) | L3_PAGE;
KASSERT((oldl2 & (ATTR_AP_RW_BIT | ATTR_SW_DBM)) !=
(ATTR_AP(ATTR_AP_RO) | ATTR_SW_DBM),
("pmap_demote_l2: L2 entry is writeable but not dirty"));
/*
* If the page table page is not leftover from an earlier promotion,
* initialize it.
* or the mapping attributes have changed, (re)initialize the L3 table.
*/
if (ml3->valid == 0) {
for (i = 0; i < Ln_ENTRIES; i++) {
l3[i] = newl3 | phys;
phys += L3_SIZE;
}
}
KASSERT(l3[0] == ((oldl2 & ~ATTR_DESCR_MASK) | L3_PAGE),
("Invalid l3 page (%lx != %lx)", l3[0],
(oldl2 & ~ATTR_DESCR_MASK) | L3_PAGE));
if (ml3->valid == 0 || (l3[0] & ATTR_MASK) != (newl3 & ATTR_MASK))
pmap_fill_l3(l3, newl3);
/*
* Map the temporary page so we don't lose access to the l2 table.