linux_dsm_epyc7002/arch
Liran Alon 1924242b2a KVM: x86: Optimization: Requst TLB flush in fast_cr3_switch() instead of do it directly
When KVM emulates a nested VMEntry (L1->L2 VMEntry), it switches mmu root
page. If nEPT is used, this will happen from
kvm_init_shadow_ept_mmu()->__kvm_mmu_new_cr3() and otherwise it will
happpen from nested_vmx_load_cr3()->kvm_mmu_new_cr3(). Either case,
__kvm_mmu_new_cr3() will use fast_cr3_switch() in attempt to switch to a
previously cached root page.

In case fast_cr3_switch() finds a matching cached root page, it will
set it in mmu->root_hpa and request KVM_REQ_LOAD_CR3 such that on
next entry to guest, KVM will set root HPA in appropriate hardware
fields (e.g. vmcs->eptp). In addition, fast_cr3_switch() calls
kvm_x86_ops->tlb_flush() in order to flush TLB as MMU root page
was replaced.

This works as mmu->root_hpa, which vmx_flush_tlb() use, was
already replaced in cached_root_available(). However, this may
result in unnecessary INVEPT execution because a KVM_REQ_TLB_FLUSH
may have already been requested. For example, by prepare_vmcs02()
in case L1 don't use VPID.

Therefore, change fast_cr3_switch() to just request TLB flush on
next entry to guest.

Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-15 11:44:11 +01:00
..
alpha mm: introduce MADV_PAGEOUT 2019-09-25 17:51:41 -07:00
arc mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
arm Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-10-19 17:09:11 -04:00
arm64 KVM/arm fixes for 5.4, take #2 2019-10-22 13:31:29 +02:00
c6x mm: consolidate pgtable_cache_init() and pgd_cache_init() 2019-09-24 15:54:09 -07:00
csky csky-for-linus-5.4-rc1: arch/csky patches for 5.4-rc1 2019-09-30 10:16:17 -07:00
h8300 mm: consolidate pgtable_cache_init() and pgd_cache_init() 2019-09-24 15:54:09 -07:00
hexagon mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
ia64 Merge branch 'akpm' (patches from Andrew) 2019-09-24 16:10:23 -07:00
m68k mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
microblaze Merge branch 'akpm' (patches from Andrew) 2019-09-24 16:10:23 -07:00
mips USB fixes for 5.4-rc3 2019-10-12 15:37:12 -07:00
nds32 mm: consolidate pgtable_cache_init() and pgd_cache_init() 2019-09-24 15:54:09 -07:00
nios2 nios2 update for v5.4-rc1 2019-09-27 13:02:19 -07:00
openrisc mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
parisc parisc: Fix vmap memory leak in ioremap()/iounmap() 2019-10-14 21:44:17 +02:00
powerpc KVM PPC update for 5.5 2019-11-01 00:35:55 +01:00
riscv RISC-V: fix virtual address overlapped in FIXADDR_START and VMEMMAP_START 2019-10-15 22:47:41 -07:00
s390 s390/uaccess: avoid (false positive) compiler warnings 2019-10-11 12:27:25 +02:00
sh mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
sparc sparc64: disable fast-GUP due to unexplained oopses 2019-10-15 09:56:36 -07:00
um mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
unicore32 mm: treewide: clarify pgtable_page_{ctor,dtor}() naming 2019-09-26 10:10:44 -07:00
x86 KVM: x86: Optimization: Requst TLB flush in fast_cr3_switch() instead of do it directly 2019-11-15 11:44:11 +01:00
xtensa xtensa: fix change_bit in exclusive access option 2019-10-16 00:14:33 -07:00
.gitignore arch: Ignore arch/i386 and arch/x86_64 2008-01-19 21:29:39 -08:00
Kconfig arm64, mm: make randomization selected by generic topdown mmap layout 2019-09-24 15:54:11 -07:00