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Flush all kernel mappings from TLB(s) in time when they are cleared.

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Replace tlb_flush_local() by tlb_flush() as even not global mappings
could be fetched to TLB(s) on other cores by speculative table walk.

From OS point of view, it was not a problem as either such mappings
were not used anymore or they were flushed from TLB(s) when reused.
However, from hardware point of view, it was a problem. Not flushed
mappings could be a target for speculative reads or prefetches (which
might be quite aggresive on ARM cores). As speculative read can fill
cacheline, it can cause a real problem, when physical page is reused,
but mapped with different memory attributes.

Anyhow, it's good to have only valid mappings in TLB(s).

Approved by:	kib (mentor)
This commit is contained in:
Svatopluk Kraus 2015-11-24 13:57:41 +00:00
parent 3164bb81e6
commit b09e6b5c6e
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=291258
2 changed files with 17 additions and 14 deletions
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27
sys/arm/arm/pmap-v6-new.c
View File

@ -1541,12 +1541,12 @@ pmap_pt2pg_zero(vm_page_t m)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(pa, PTE2_AP_KRW,
m->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR2);
/* Even VM_ALLOC_ZERO request is only advisory. */
if ((m->flags & PG_ZERO) == 0)
pagezero(sysmaps->CADDR2);
pte2_sync_range((pt2_entry_t *)sysmaps->CADDR2, PAGE_SIZE);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
@ -5470,7 +5470,6 @@ pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
struct sysmaps *sysmaps;
vm_memattr_t oma;
vm_paddr_t pa;
vm_offset_t va;
oma = m->md.pat_mode;
m->md.pat_mode = ma;
@ -5502,10 +5501,9 @@ pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
if (*sysmaps->CMAP2)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(pa, PTE2_AP_KRW, ma));
va = (vm_offset_t)sysmaps->CADDR2;
tlb_flush_local(va);
dcache_wbinv_poc(va, pa, PAGE_SIZE);
dcache_wbinv_poc((vm_offset_t)sysmaps->CADDR2, pa, PAGE_SIZE);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -5594,9 +5592,9 @@ pmap_zero_page(vm_page_t m)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
m->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR2);
pagezero(sysmaps->CADDR2);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -5619,12 +5617,12 @@ pmap_zero_page_area(vm_page_t m, int off, int size)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
m->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR2);
if (off == 0 && size == PAGE_SIZE)
pagezero(sysmaps->CADDR2);
else
bzero(sysmaps->CADDR2 + off, size);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -5644,9 +5642,9 @@ pmap_zero_page_idle(vm_page_t m)
sched_pin();
pte2_store(CMAP3, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
m->md.pat_mode));
tlb_flush_local((vm_offset_t)CADDR3);
pagezero(CADDR3);
pte2_clear(CMAP3);
tlb_flush((vm_offset_t)CADDR3);
sched_unpin();
}
@ -5670,13 +5668,13 @@ pmap_copy_page(vm_page_t src, vm_page_t dst)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP1, PTE2_KERN_NG(VM_PAGE_TO_PHYS(src),
PTE2_AP_KR | PTE2_NM, src->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR1);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(VM_PAGE_TO_PHYS(dst),
PTE2_AP_KRW, dst->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR2);
bcopy(sysmaps->CADDR1, sysmaps->CADDR2, PAGE_SIZE);
pte2_clear(sysmaps->CMAP1);
tlb_flush((vm_offset_t)sysmaps->CADDR1);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -5721,7 +5719,9 @@ pmap_copy_pages(vm_page_t ma[], vm_offset_t a_offset, vm_page_t mb[],
xfersize -= cnt;
}
pte2_clear(sysmaps->CMAP1);
tlb_flush((vm_offset_t)sysmaps->CADDR1);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -5740,8 +5740,6 @@ pmap_quick_enter_page(vm_page_t m)
pte2_store(pte2p, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
pmap_page_get_memattr(m)));
tlb_flush_local(qmap_addr);
return (qmap_addr);
}
@ -5758,6 +5756,7 @@ pmap_quick_remove_page(vm_offset_t addr)
KASSERT(pte2_load(pte2p) != 0, ("%s: PTE2 not in use", __func__));
pte2_clear(pte2p);
tlb_flush(qmap_addr);
critical_exit();
}
@ -6059,9 +6058,9 @@ pmap_dcache_wb_pou(vm_paddr_t pa, vm_size_t size, vm_memattr_t ma)
if (*sysmaps->CMAP3)
panic("%s: CMAP3 busy", __func__);
pte2_store(sysmaps->CMAP3, PTE2_KERN_NG(pa, PTE2_AP_KRW, ma));
tlb_flush_local((vm_offset_t)sysmaps->CADDR3);
dcache_wb_pou((vm_offset_t)sysmaps->CADDR3 + (pa & PAGE_MASK), size);
pte2_clear(sysmaps->CMAP3);
tlb_flush((vm_offset_t)sysmaps->CADDR3);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}
@ -6313,13 +6312,13 @@ pmap_zero_page_check(vm_page_t m)
panic("%s: CMAP2 busy", __func__);
pte2_store(sysmaps->CMAP2, PTE2_KERN_NG(VM_PAGE_TO_PHYS(m), PTE2_AP_KRW,
m->md.pat_mode));
tlb_flush_local((vm_offset_t)sysmaps->CADDR2);
end = (uint32_t*)(sysmaps->CADDR2 + PAGE_SIZE);
for (p = (uint32_t*)sysmaps->CADDR2; p < end; p++)
if (*p != 0)
panic("%s: page %p not zero, va: %p", __func__, m,
sysmaps->CADDR2);
pte2_clear(sysmaps->CMAP2);
tlb_flush((vm_offset_t)sysmaps->CADDR2);
sched_unpin();
mtx_unlock(&sysmaps->lock);
}

4
sys/arm/include/sf_buf.h
View File

@ -44,7 +44,11 @@ static inline int
sf_buf_unmap(struct sf_buf *sf)
{
#ifdef ARM_NEW_PMAP
pmap_qremove(sf->kva, 1);
#else
pmap_kremove(sf->kva);
#endif
return (1);
}
#endif /* !_MACHINE_SF_BUF_H_ */