Commit Graph

117 Commits

Author SHA1 Message Date
Dong, Eddie 20c466b561 KVM: Use rsvd_bits_mask in load_pdptrs()
Also remove bit 5-6 from rsvd_bits_mask per latest SDM.

Signed-off-by: Eddie Dong <Eddie.Dong@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:36 +03:00
Dong, Eddie 82725b20e2 KVM: MMU: Emulate #PF error code of reserved bits violation
Detect, indicate, and propagate page faults where reserved bits are set.
Take care to handle the different paging modes, each of which has different
sets of reserved bits.

[avi: fix pte reserved bits for efer.nxe=0]

Signed-off-by: Eddie Dong <eddie.dong@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:35 +03:00
Gleb Natapov f00be0cae4 KVM: MMU: do not free active mmu pages in free_mmu_pages()
free_mmu_pages() should only undo what alloc_mmu_pages() does.
Free mmu pages from the generic VM destruction function, kvm_destroy_vm().

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:30 +03:00
Avi Kivity a8cd0244e9 KVM: Make paravirt tlb flush also reload the PAE PDPTRs
The paravirt tlb flush may be used not only to flush TLBs, but also
to reload the four page-directory-pointer-table entries, as it is used
as a replacement for reloading CR3.  Change the code to do the entire
CR3 reloading dance instead of simply flushing the TLB.

Cc: stable@kernel.org
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-05-25 20:00:50 +03:00
Marcelo Tosatti bf47a760f6 KVM: MMU: disable global page optimization
Complexity to fix it not worthwhile the gains, as discussed
in http://article.gmane.org/gmane.comp.emulators.kvm.devel/28649.

Cc: stable@kernel.org
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-04-22 13:52:09 +03:00
Hannes Eder cded19f396 KVM: fix sparse warnings: Should it be static?
Impact: Make symbols static.

Fix this sparse warnings:
  arch/x86/kvm/mmu.c:992:5: warning: symbol 'mmu_pages_add' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1124:5: warning: symbol 'mmu_pages_next' was not declared. Should it be static?
  arch/x86/kvm/mmu.c:1144:6: warning: symbol 'mmu_pages_clear_parents' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2037:5: warning: symbol 'kvm_read_guest_virt' was not declared. Should it be static?
  arch/x86/kvm/x86.c:2067:5: warning: symbol 'kvm_write_guest_virt' was not declared. Should it be static?
  virt/kvm/irq_comm.c:220:5: warning: symbol 'setup_routing_entry' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:14 +02:00
Joerg Roedel 452425dbaa KVM: MMU: remove assertion in kvm_mmu_alloc_page
The assertion no longer makes sense since we don't clear page tables on
allocation; instead we clear them during prefetch.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:10 +02:00
Joerg Roedel 6bed6b9e84 KVM: MMU: remove redundant check in mmu_set_spte
The following code flow is unnecessary:

	if (largepage)
		was_rmapped = is_large_pte(*shadow_pte);
	 else
	 	was_rmapped = 1;

The is_large_pte() function will always evaluate to one here because the
(largepage && !is_large_pte) case is already handled in the first
if-clause. So we can remove this check and set was_rmapped to one always
here.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:10 +02:00
Avi Kivity f6e2c02b6d KVM: MMU: Rename "metaphysical" attribute to "direct"
This actually describes what is going on, rather than alerting the reader
that something strange is going on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Marcelo Tosatti 9903a927a4 KVM: MMU: drop zeroing on mmu_memory_cache_alloc
Zeroing on mmu_memory_cache_alloc is unnecessary since:

- Smaller areas are pre-allocated with kmem_cache_zalloc.
- Page pointed by ->spt is overwritten with prefetch_page
  and entries in page pointed by ->gfns are initialized
  before reading.

[avi: zeroing pages is unnecessary]

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:04 +02:00
Avi Kivity 4677a3b693 KVM: MMU: Optimize page unshadowing
Using kvm_mmu_lookup_page() will result in multiple scans of the hash chains;
use hlist_for_each_entry_safe() to achieve a single scan instead.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:03:02 +02:00
Avi Kivity e8c4a4e8a7 KVM: MMU: Drop walk_shadow()
No longer used.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:53 +02:00
Avi Kivity 9f652d21c3 KVM: MMU: Use for_each_shadow_entry() in __direct_map()
Eliminating a callback and a useless structure.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:52 +02:00
Avi Kivity 2d11123a77 KVM: MMU: Add for_each_shadow_entry(), a simpler alternative to walk_shadow()
Using a for_each loop style removes the need to write callback and nasty
casts.

Implement the walk_shadow() using the for_each_shadow_entry().

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:52 +02:00
Avi Kivity e207831804 KVM: MMU: Initialize a shadow page's global attribute from cr4.pge
If cr4.pge is cleared, we ought to treat any ptes in the page as non-global.
This allows us to remove the check from set_spte().

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Avi Kivity a770f6f28b KVM: MMU: Inherit a shadow page's guest level count from vcpu setup
Instead of "calculating" it on every shadow page allocation, set it once
when switching modes, and copy it when allocating pages.

This doesn't buy us much, but sets up the stage for inheriting more
information related to the mmu setup.

Signed-off-by: Avi Kivity <avi@redhat.com>
2009-03-24 11:02:51 +02:00
Sheng Yang 2aaf69dcee KVM: MMU: Map device MMIO as UC in EPT
Software are not allow to access device MMIO using cacheable memory type, the
patch limit MMIO region with UC and WC(guest can select WC using PAT and
PCD/PWT).

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:37 +02:00
Marcelo Tosatti 8791723920 KVM: MMU: handle large host sptes on invlpg/resync
The invlpg and sync walkers lack knowledge of large host sptes,
descending to non-existant pagetable level.

Stop at directory level in such case.

Fixes SMP Windows XP with hugepages.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:49 +02:00
Avi Kivity 25e2343246 KVM: MMU: Don't treat a global pte as such if cr4.pge is cleared
The pte.g bit is meaningless if global pages are disabled; deferring
mmu page synchronization on these ptes will lead to the guest using stale
shadow ptes.

Fixes Vista x86 smp bootloader failure.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:48 +02:00
Marcelo Tosatti eb64f1e8cd KVM: MMU: check for present pdptr shadow page in walk_shadow
walk_shadow assumes the caller verified validity of the pdptr pointer in
question, which is not the case for the invlpg handler.

Fixes oops during Solaris 10 install.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:46 +02:00
Marcelo Tosatti ad218f85e3 KVM: MMU: prepopulate the shadow on invlpg
If the guest executes invlpg, peek into the pagetable and attempt to
prepopulate the shadow entry.

Also stop dirty fault updates from interfering with the fork detector.

2% improvement on RHEL3/AIM7.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:44 +02:00
Marcelo Tosatti 6cffe8ca4a KVM: MMU: skip global pgtables on sync due to cr3 switch
Skip syncing global pages on cr3 switch (but not on cr4/cr0). This is
important for Linux 32-bit guests with PAE, where the kmap page is
marked as global.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:44 +02:00
Marcelo Tosatti b1a368218a KVM: MMU: collapse remote TLB flushes on root sync
Collapse remote TLB flushes on root sync.

kernbench is 2.7% faster on 4-way guest. Improvements have been seen
with other loads such as AIM7.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:43 +02:00
Marcelo Tosatti 60c8aec6e2 KVM: MMU: use page array in unsync walk
Instead of invoking the handler directly collect pages into
an array so the caller can work with it.

Simplifies TLB flush collapsing.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:43 +02:00
Marcelo Tosatti ecc5589f19 KVM: MMU: optimize set_spte for page sync
The write protect verification in set_spte is unnecessary for page sync.

Its guaranteed that, if the unsync spte was writable, the target page
does not have a write protected shadow (if it had, the spte would have
been write protected under mmu_lock by rmap_write_protect before).

Same reasoning applies to mark_page_dirty: the gfn has been marked as
dirty via the pagefault path.

The cost of hash table and memslot lookups are quite significant if the
workload is pagetable write intensive resulting in increased mmu_lock
contention.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Eduardo Habkost 13673a90f1 KVM: VMX: move vmx.h to include/asm
vmx.h will be used by core code that is independent of KVM, so I am
moving it outside the arch/x86/kvm directory.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:27 +02:00
Izik Eidus 2843099fee KVM: MMU: Fix aliased gfns treated as unaliased
Some areas of kvm x86 mmu are using gfn offset inside a slot without
unaliasing the gfn first.  This patch makes sure that the gfn will be
unaliased and add gfn_to_memslot_unaliased() to save the calculating
of the gfn unaliasing in case we have it unaliased already.

Signed-off-by: Izik Eidus <ieidus@redhat.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:50 +02:00
Sheng Yang 291f26bc0f KVM: MMU: Extend kvm_mmu_page->slot_bitmap size
Otherwise set_bit() for private memory slot(above KVM_MEMORY_SLOTS) would
corrupted memory in 32bit host.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:45 +02:00
Sheng Yang 64d4d52175 KVM: Enable MTRR for EPT
The effective memory type of EPT is the mixture of MSR_IA32_CR_PAT and memory
type field of EPT entry.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:45 +02:00
Sheng Yang 74be52e3e6 KVM: Add local get_mtrr_type() to support MTRR
For EPT memory type support.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:51:45 +02:00
Marcelo Tosatti 0c0f40bdbe KVM: MMU: fix sync of ptes addressed at owner pagetable
During page sync, if a pagetable contains a self referencing pte (that
points to the pagetable), the corresponding spte may be marked as
writable even though all mappings are supposed to be write protected.

Fix by clearing page unsync before syncing individual sptes.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-11-23 15:24:19 +02:00
Marcelo Tosatti c41ef344de KVM: MMU: increase per-vcpu rmap cache alloc size
The page fault path can use two rmap_desc structures, if:

- walk_addr's dirty pte update allocates one rmap_desc.
- mmu_lock is dropped, sptes are zapped resulting in rmap_desc being
freed.
- fetch->mmu_set_spte allocates another rmap_desc.

Increase to 4 for safety.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-11-11 20:53:34 +02:00
Marcelo Tosatti 6ad9f15c94 KVM: MMU: sync root on paravirt TLB flush
The pvmmu TLB flush handler should request a root sync, similarly to
a native read-write CR3.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-28 14:09:27 +02:00
Marcelo Tosatti 582801a95d KVM: MMU: add "oos_shadow" parameter to disable oos
Subject says it all.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:27 +02:00
Marcelo Tosatti 0074ff63eb KVM: MMU: speed up mmu_unsync_walk
Cache the unsynced children information in a per-page bitmap.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:26 +02:00
Marcelo Tosatti 4731d4c7a0 KVM: MMU: out of sync shadow core
Allow guest pagetables to go out of sync.  Instead of emulating write
accesses to guest pagetables, or unshadowing them, we un-write-protect
the page table and allow the guest to modify it at will.  We rely on
invlpg executions to synchronize individual ptes, and will synchronize
the entire pagetable on tlb flushes.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:25 +02:00
Marcelo Tosatti 6844dec694 KVM: MMU: mmu_convert_notrap helper
Need to convert shadow_notrap_nonpresent -> shadow_trap_nonpresent when
unsyncing pages.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:24 +02:00
Marcelo Tosatti 0738541396 KVM: MMU: awareness of new kvm_mmu_zap_page behaviour
kvm_mmu_zap_page will soon zap the unsynced children of a page. Restart
list walk in such case.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:23 +02:00
Marcelo Tosatti ad8cfbe3ff KVM: MMU: mmu_parent_walk
Introduce a function to walk all parents of a given page, invoking a handler.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:22 +02:00
Marcelo Tosatti a7052897b3 KVM: x86: trap invlpg
With pages out of sync invlpg needs to be trapped. For now simply nuke
the entry.

Untested on AMD.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:21 +02:00
Marcelo Tosatti 0ba73cdadb KVM: MMU: sync roots on mmu reload
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:20 +02:00
Marcelo Tosatti e8bc217aef KVM: MMU: mode specific sync_page
Examine guest pagetable and bring the shadow back in sync. Caller is responsible
for local TLB flush before re-entering guest mode.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:19 +02:00
Marcelo Tosatti 38187c830c KVM: MMU: do not write-protect large mappings
There is not much point in write protecting large mappings. This
can only happen when a page is shadowed during the window between
is_largepage_backed and mmu_lock acquision. Zap the entry instead, so
the next pagefault will find a shadowed page via is_largepage_backed and
fallback to 4k translations.

Simplifies out of sync shadow.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:18 +02:00
Marcelo Tosatti a378b4e64c KVM: MMU: move local TLB flush to mmu_set_spte
Since the sync page path can collapse flushes.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:17 +02:00
Marcelo Tosatti 1e73f9dd88 KVM: MMU: split mmu_set_spte
Split the spte entry creation code into a new set_spte function.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:16 +02:00
Marcelo Tosatti 4c2155ce81 KVM: switch to get_user_pages_fast
Convert gfn_to_pfn to use get_user_pages_fast, which can do lockless
pagetable lookups on x86. Kernel compilation on 4-way guest is 3.7%
faster on VMX.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-10-15 14:25:06 +02:00
Sheng Yang d40a1ee485 KVM: MMU: Modify kvm_shadow_walk.entry to accept u64 addr
EPT is 4 level by default in 32pae(48 bits), but the addr parameter
of kvm_shadow_walk->entry() only accept unsigned long as virtual
address, which is 32bit in 32pae. This result in SHADOW_PT_INDEX()
overflow when try to fetch level 4 index.

Fix it by extend kvm_shadow_walk->entry() to accept 64bit addr in
parameter.

Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:25 +02:00
Avi Kivity 3201b5d9f0 KVM: MMU: Fix setting the accessed bit on non-speculative sptes
The accessed bit was accidentally turned on in a random flag word, rather
than, the spte itself, which was lucky, since it used the non-EPT compatible
PT_ACCESSED_MASK.

Fix by turning the bit on in the spte and changing it to use the portable
accessed mask.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:24 +02:00
Avi Kivity 171d595d3b KVM: MMU: Flush tlbs after clearing write permission when accessing dirty log
Otherwise, the cpu may allow writes to the tracked pages, and we lose
some display bits or fail to migrate correctly.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:24 +02:00
Avi Kivity 2245a28fe2 KVM: MMU: Add locking around kvm_mmu_slot_remove_write_access()
It was generally safe due to slots_lock being held for write, but it wasn't
very nice.

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:24 +02:00