From: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
To: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
Cc: akpm-3NddpPZAyC0@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: [PATCH 15/33] KVM: MMU: Implement child shadow unlinking
Date: Thu, 04 Jan 2007 16:04:06 -0000 [thread overview]
Message-ID: <20070104160406.E660A250048@il.qumranet.com> (raw)
In-Reply-To: <459D21DD.5090506-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
When removing a page table, we must maintain the parent_pte field all child
shadow page tables.
Signed-off-by: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
Index: linux-2.6/drivers/kvm/mmu.c
===================================================================
--- linux-2.6.orig/drivers/kvm/mmu.c
+++ linux-2.6/drivers/kvm/mmu.c
@@ -402,12 +402,21 @@ static void mmu_page_remove_parent_pte(s
break;
if (pte_chain->parent_ptes[i] != parent_pte)
continue;
- while (i + 1 < NR_PTE_CHAIN_ENTRIES) {
+ while (i + 1 < NR_PTE_CHAIN_ENTRIES
+ && pte_chain->parent_ptes[i + 1]) {
pte_chain->parent_ptes[i]
= pte_chain->parent_ptes[i + 1];
++i;
}
pte_chain->parent_ptes[i] = NULL;
+ if (i == 0) {
+ hlist_del(&pte_chain->link);
+ kfree(pte_chain);
+ if (hlist_empty(&page->parent_ptes)) {
+ page->multimapped = 0;
+ page->parent_pte = NULL;
+ }
+ }
return;
}
BUG();
@@ -481,7 +490,30 @@ static struct kvm_mmu_page *kvm_mmu_get_
static void kvm_mmu_page_unlink_children(struct kvm_vcpu *vcpu,
struct kvm_mmu_page *page)
{
- BUG();
+ unsigned i;
+ u64 *pt;
+ u64 ent;
+
+ pt = __va(page->page_hpa);
+
+ if (page->role.level == PT_PAGE_TABLE_LEVEL) {
+ for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
+ if (pt[i] & PT_PRESENT_MASK)
+ rmap_remove(vcpu->kvm, &pt[i]);
+ pt[i] = 0;
+ }
+ return;
+ }
+
+ for (i = 0; i < PT64_ENT_PER_PAGE; ++i) {
+ ent = pt[i];
+
+ pt[i] = 0;
+ if (!(ent & PT_PRESENT_MASK))
+ continue;
+ ent &= PT64_BASE_ADDR_MASK;
+ mmu_page_remove_parent_pte(page_header(ent), &pt[i]);
+ }
}
static void kvm_mmu_put_page(struct kvm_vcpu *vcpu,
@@ -489,8 +521,7 @@ static void kvm_mmu_put_page(struct kvm_
u64 *parent_pte)
{
mmu_page_remove_parent_pte(page, parent_pte);
- if (page->role.level > PT_PAGE_TABLE_LEVEL)
- kvm_mmu_page_unlink_children(vcpu, page);
+ kvm_mmu_page_unlink_children(vcpu, page);
hlist_del(&page->hash_link);
list_del(&page->link);
list_add(&page->link, &vcpu->free_pages);
@@ -511,6 +542,7 @@ static void kvm_mmu_zap_page(struct kvm_
struct kvm_pte_chain, link);
parent_pte = chain->parent_ptes[0];
}
+ BUG_ON(!parent_pte);
kvm_mmu_put_page(vcpu, page, parent_pte);
*parent_pte = 0;
}
@@ -530,6 +562,8 @@ static int kvm_mmu_unprotect_page(struct
bucket = &vcpu->kvm->mmu_page_hash[index];
hlist_for_each_entry_safe(page, node, n, bucket, hash_link)
if (page->gfn == gfn && !page->role.metaphysical) {
+ pgprintk("%s: gfn %lx role %x\n", __FUNCTION__, gfn,
+ page->role.word);
kvm_mmu_zap_page(vcpu, page);
r = 1;
}
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys - and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
next prev parent reply other threads:[~2007-01-04 16:04 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-01-04 15:48 [PATCH 0/33] KVM: MMU: Cache shadow page tables Avi Kivity
2007-01-04 15:50 ` [PATCH 1/33] KVM: MMU: Implement simple reverse mapping Avi Kivity
[not found] ` <459D21DD.5090506-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-01-04 15:51 ` [PATCH 2/33] KVM: MMU: Teach the page table walker to track guest page table gfns Avi Kivity
2007-01-04 15:52 ` [PATCH 3/33] KVM: MMU: Load the pae pdptrs on cr3 change like the processor does Avi Kivity
2007-01-04 15:53 ` [PATCH 4/33] KVM: MMU: Fold fetch_guest() into init_walker() Avi Kivity
2007-01-04 15:54 ` [PATCH 5/33] KVM: MU: Special treatment for shadow pae root pages Avi Kivity
2007-01-04 15:55 ` [PATCH 6/33] KVM: MMU: Use the guest pdptrs instead of mapping cr3 in pae mode Avi Kivity
2007-01-04 15:56 ` [PATCH 7/33] KVM: MMU: Make the shadow page tables also special-case pae Avi Kivity
2007-01-04 15:57 ` [PATCH 8/33] KVM: MMU: Make kvm_mmu_alloc_page() return a kvm_mmu_page pointer Avi Kivity
2007-01-04 15:58 ` [PATCH 9/33] KVM: MMU: Shadow page table caching Avi Kivity
2007-01-04 15:59 ` [PATCH 10/33] KVM: MMU: Write protect guest pages when a shadow is created for them Avi Kivity
2007-01-04 16:00 ` [PATCH 11/33] KVM: MMU: Let the walker extract the target page gfn from the pte Avi Kivity
2007-01-04 16:01 ` [PATCH 12/33] KVM: MMU: Support emulated writes into RAM Avi Kivity
2007-01-04 16:02 ` [PATCH 13/33] KVM: MMU: Zap shadow page table entries on writes to guest page tables Avi Kivity
2007-01-04 16:03 ` [PATCH 14/33] KVM: MMU: If emulating an instruction fails, try unprotecting the page Avi Kivity
2007-01-04 16:04 ` Avi Kivity [this message]
2007-01-04 16:06 ` [PATCH 17/33] KVM: MMU: oom handling Avi Kivity
2007-01-04 16:07 ` [PATCH 18/33] KVM: MMU: Remove invlpg interception Avi Kivity
2007-01-04 16:08 ` [PATCH 19/33] KVM: MMU: Remove release_pt_page_64() Avi Kivity
2007-01-04 16:10 ` [PATCH 21/33] KVM: MMU: <ove is_empty_shadow_page() above kvm_mmu_free_page() Avi Kivity
2007-01-04 16:11 ` [PATCH 22/33] KVM: MMU: Ensure freed shadow pages are clean Avi Kivity
2007-01-04 16:13 ` [PATCH 24/33] KVM: MMU: Page table write flood protection Avi Kivity
2007-01-04 16:14 ` [PATCH 25/33] KVM: MMU: Never free a shadow page actively serving as a root Avi Kivity
2007-01-04 16:15 ` [PATCH 26/33] KVM: MMU: Fix cmpxchg8b emulation Avi Kivity
2007-01-04 16:16 ` [PATCH 27/33] KVM: MMU: Treat user-mode faults as a hint that a page is no longer a page table Avi Kivity
2007-01-04 16:17 ` [PATCH 28/33] KVM: MMU: Free pages on kvm destruction Avi Kivity
2007-01-04 16:18 ` [PATCH 29/33] KVM: MMU: Replace atomic allocations by preallocated objects Avi Kivity
2007-01-04 16:19 ` [PATCH 30/33] KVM: MMU: Detect oom conditions and propagate error to userspace Avi Kivity
2007-01-04 16:20 ` [PATCH 31/33] KVM: MMU: Flush guest tlb when reducing permissions on a pte Avi Kivity
2007-01-04 16:21 ` [PATCH 32/33] KVM: MMU: Destroy mmu while we still have a vcpu left Avi Kivity
2007-01-04 16:22 ` [PATCH 33/33] KVM: MMU: add audit code to check mappings, etc are correct Avi Kivity
2007-01-04 17:22 ` [PATCH 0/33] KVM: MMU: Cache shadow page tables Andrew Morton
[not found] ` <20070104092226.91fa2dfe.akpm-3NddpPZAyC0@public.gmane.org>
2007-01-04 17:41 ` Avi Kivity
[not found] ` <459D3C65.2090703-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
2007-01-04 18:02 ` Ingo Molnar
2007-01-04 16:05 ` [PATCH 16/33] KVM: MMU: kvm_mmu_put_page() only removes one link to the page Avi Kivity
2007-01-04 16:09 ` [PATCH 20/33] KVM: MMU: Handle misaligned accesses to write protected guest page tables Avi Kivity
2007-01-04 16:12 ` [PATCH 23/33] KVM: MMU: If an empty shadow page is not empty, report more info Avi Kivity
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20070104160406.E660A250048@il.qumranet.com \
--to=avi-atkuwr5tajbwk0htik3j/w@public.gmane.org \
--cc=akpm-3NddpPZAyC0@public.gmane.org \
--cc=kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox