On ThunderX2 we need to be careful to only map the memory the firmware

lists in the EFI memory map. As such we need to reduce the mappings to
restrict them to not be the full 1G block. For now reduce this to a 2M
block, however this may be further restricted to be 4k page aligned as
other SoCs may require.

This allows ThunderX2 to boot reliably to userspace without performing
any speculative memory accesses to invalid physical memory.

This is a recommit of r334035 now that we can access the EFI Runtime data
through the DMAP region.

Tested by:	tuexen
Sponsored by:	DARPA, AFRL
This commit is contained in:
Andrew Turner 2018-05-29 13:52:25 +00:00
parent 4f2190efce
commit 463ac3dda0

View File

@ -590,33 +590,100 @@ pmap_early_vtophys(vm_offset_t l1pt, vm_offset_t va)
return ((l2[l2_slot] & ~ATTR_MASK) + (va & L2_OFFSET));
}
static void
pmap_bootstrap_dmap(vm_offset_t kern_l1, vm_paddr_t min_pa, vm_paddr_t max_pa)
static vm_offset_t
pmap_bootstrap_dmap(vm_offset_t kern_l1, vm_paddr_t min_pa,
vm_offset_t freemempos)
{
pt_entry_t *l2;
vm_offset_t va;
vm_paddr_t pa;
u_int l1_slot;
vm_paddr_t l2_pa, pa;
u_int l1_slot, l2_slot, prev_l1_slot;
int i;
dmap_phys_base = min_pa & ~L1_OFFSET;
dmap_phys_max = 0;
dmap_max_addr = 0;
l2 = NULL;
prev_l1_slot = -1;
#define DMAP_TABLES ((DMAP_MAX_ADDRESS - DMAP_MIN_ADDRESS) >> L0_SHIFT)
memset(pagetable_dmap, 0, PAGE_SIZE * DMAP_TABLES);
for (i = 0; i < (physmap_idx * 2); i += 2) {
pa = physmap[i] & ~L1_OFFSET;
pa = physmap[i] & ~L2_OFFSET;
va = pa - dmap_phys_base + DMAP_MIN_ADDRESS;
for (; va < DMAP_MAX_ADDRESS && pa < physmap[i + 1];
/* Create L2 mappings at the start of the region */
if ((pa & L1_OFFSET) != 0) {
l1_slot = ((va - DMAP_MIN_ADDRESS) >> L1_SHIFT);
if (l1_slot != prev_l1_slot) {
prev_l1_slot = l1_slot;
l2 = (pt_entry_t *)freemempos;
l2_pa = pmap_early_vtophys(kern_l1,
(vm_offset_t)l2);
freemempos += PAGE_SIZE;
pmap_load_store(&pagetable_dmap[l1_slot],
(l2_pa & ~Ln_TABLE_MASK) | L1_TABLE);
memset(l2, 0, PAGE_SIZE);
}
KASSERT(l2 != NULL,
("pmap_bootstrap_dmap: NULL l2 map"));
for (; va < DMAP_MAX_ADDRESS && pa < physmap[i + 1];
pa += L2_SIZE, va += L2_SIZE) {
/*
* We are on a boundary, stop to
* create a level 1 block
*/
if ((pa & L1_OFFSET) == 0)
break;
l2_slot = pmap_l2_index(va);
KASSERT(l2_slot != 0, ("..."));
pmap_load_store(&l2[l2_slot],
(pa & ~L2_OFFSET) | ATTR_DEFAULT | ATTR_XN |
ATTR_IDX(CACHED_MEMORY) | L2_BLOCK);
}
KASSERT(va == (pa - dmap_phys_base + DMAP_MIN_ADDRESS),
("..."));
}
for (; va < DMAP_MAX_ADDRESS && pa < physmap[i + 1] &&
(physmap[i + 1] - pa) >= L1_SIZE;
pa += L1_SIZE, va += L1_SIZE) {
l1_slot = ((va - DMAP_MIN_ADDRESS) >> L1_SHIFT);
/* We already have an entry */
if (pagetable_dmap[l1_slot] != 0)
continue;
pmap_load_store(&pagetable_dmap[l1_slot],
(pa & ~L1_OFFSET) | ATTR_DEFAULT | ATTR_XN |
ATTR_IDX(CACHED_MEMORY) | L1_BLOCK);
}
/* Create L2 mappings at the end of the region */
if (pa < physmap[i + 1]) {
l1_slot = ((va - DMAP_MIN_ADDRESS) >> L1_SHIFT);
if (l1_slot != prev_l1_slot) {
prev_l1_slot = l1_slot;
l2 = (pt_entry_t *)freemempos;
l2_pa = pmap_early_vtophys(kern_l1,
(vm_offset_t)l2);
freemempos += PAGE_SIZE;
pmap_load_store(&pagetable_dmap[l1_slot],
(l2_pa & ~Ln_TABLE_MASK) | L1_TABLE);
memset(l2, 0, PAGE_SIZE);
}
KASSERT(l2 != NULL,
("pmap_bootstrap_dmap: NULL l2 map"));
for (; va < DMAP_MAX_ADDRESS && pa < physmap[i + 1];
pa += L2_SIZE, va += L2_SIZE) {
l2_slot = pmap_l2_index(va);
pmap_load_store(&l2[l2_slot],
(pa & ~L2_OFFSET) | ATTR_DEFAULT | ATTR_XN |
ATTR_IDX(CACHED_MEMORY) | L2_BLOCK);
}
}
if (pa > dmap_phys_max) {
dmap_phys_max = pa;
dmap_max_addr = va;
@ -624,6 +691,8 @@ pmap_bootstrap_dmap(vm_offset_t kern_l1, vm_paddr_t min_pa, vm_paddr_t max_pa)
}
cpu_tlb_flushID();
return (freemempos);
}
static vm_offset_t
@ -729,8 +798,11 @@ pmap_bootstrap(vm_offset_t l0pt, vm_offset_t l1pt, vm_paddr_t kernstart,
max_pa = physmap[i + 1];
}
freemempos = KERNBASE + kernlen;
freemempos = roundup2(freemempos, PAGE_SIZE);
/* Create a direct map region early so we can use it for pa -> va */
pmap_bootstrap_dmap(l1pt, min_pa, max_pa);
freemempos = pmap_bootstrap_dmap(l1pt, min_pa, freemempos);
va = KERNBASE;
start_pa = pa = KERNBASE - kern_delta;
@ -762,8 +834,6 @@ pmap_bootstrap(vm_offset_t l0pt, vm_offset_t l1pt, vm_paddr_t kernstart,
va = roundup2(va, L1_SIZE);
freemempos = KERNBASE + kernlen;
freemempos = roundup2(freemempos, PAGE_SIZE);
/* Create the l2 tables up to VM_MAX_KERNEL_ADDRESS */
freemempos = pmap_bootstrap_l2(l1pt, va, freemempos);
/* And the l3 tables for the early devmap */