From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: nsaenz@amazon.com, vkuznets@redhat.com, snambakam@linux.microsoft.com
Subject: [PATCH v2 20/28] KVM: pfncache: Fail to refresh if it contains memory protections
Date: Fri, 18 Sep 2026 04:15:35 -0400 [thread overview]
Message-ID: <20260918081543.139871-21-pbonzini@redhat.com> (raw)
In-Reply-To: <20260918081543.139871-1-pbonzini@redhat.com>
From: Nicolas Saenz Julienne <nsaenz@amazon.com>
Similar to how pfncache disallows caching gfns mapped within read-only
memory slots, gfns marked as read-only by memory attributes must
fail to initialize. Unsurprisingly, the same behaviour applies to gfns
mapped as non-accessible (NR/NW), while non-executable mappings are fine.
Signed-off-by: Nicolas Saenz Julienne <nsaenz@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
virt/kvm/pfncache.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c
index 46ffae69fe77..39935740136d 100644
--- a/virt/kvm/pfncache.c
+++ b/virt/kvm/pfncache.c
@@ -298,7 +298,18 @@ static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned l
gpc->gpa != gpa || kvm_is_error_hva(gpc->uhva)) {
gfn_t gfn = gpa_to_gfn(gpa);
+ /*
+ * RW memory attributes are incompatible with GPC. The
+ * RW protection check has to happen after storing the
+ * generation number.
+ */
gpc->attrs_generation = kvm_mem_attributes_generation(kvm);
+ if (kvm_range_has_rw_memory_protections(kvm, gfn, gfn + 1)) {
+ gpc->uhva = KVM_HVA_ERR_BAD;
+ ret = -EFAULT;
+ goto out;
+ }
+
gpc->gpa = gpa;
gpc->slots_generation = slots->generation;
gpc->memslot = __gfn_to_memslot(slots, gfn);
--
2.52.0
next prev parent reply other threads:[~2026-09-18 8:16 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-18 8:15 [PATCH v2 00/28] KVM: x86: Introduce memory protection attributes Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 01/28] KVM: selftests: Take into account mixed memory fault flags Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 02/28] KVM: Define and communicate KVM_EXIT_MEMORY_FAULT RWX flags to userspace Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 03/28] KVM: selftests: Test address translation for Hyper-V direct L2 hypercalls Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 04/28] KVM: apply nGPA->GPA translation to KVM_HC_CLOCK_PAIRING Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 05/28] KVM: x86: Introduce memory fault on invalid hypercalls reads/writes Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 06/28] KVM: selftests: test hypercall memory fault exits Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 07/28] KVM: x86/mmu: intersect writability from __kvm_faultin_pfn with fault->map_writable Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 08/28] KVM: x86/mmu: Extend map_writable to a full ACC_* mask Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 09/28] KVM: x86/mmu: Init memslot hugepage information for non-private_mem VMs too Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 10/28] KVM: pass kvm == NULL case to kvm_arch_has_private_mem Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 11/28] KVM: adjust for presence of more than one attribute Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 12/28] KVM: Introduce NR/NW/NX memory attributes Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 13/28] KVM: Include memory protections in result of gfn->hva conversion Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 14/28] KVM: Introduce kvm_fetch_guest_page() and use it for x86 Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 15/28] KVM: Take memory protections into account for memory read/write/fetch Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 16/28] KVM: Encapsulate memattrs array into anonymous struct Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 17/28] KVM: Introduce kvm_check_gen()/kvm_memslots_check_gen() Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 18/28] KVM: Introduce a generation number for memory attributes Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 19/28] KVM: Take memory protections into account for accesses with cached gfn->hva Paolo Bonzini
2026-09-18 8:15 ` Paolo Bonzini [this message]
2026-09-18 8:15 ` [PATCH v2 21/28] KVM: x86/mmu: Take memory protection attributes into account during faults Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 22/28] KVM: x86/mmu: Issue memory fault exit if walk failed due to memory attribute Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 23/28] KVM: x86/mmu: Do not update accessed/dirty if guest PTE is read-only Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 24/28] KVM: x86/mmu: Do not prefetch sptes on gfns backed by memory attributes Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 25/28] KVM: x86/mmu: Obsolete all roots if memattr contains gPTEs Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 26/28] KVM: x86: selftests: Introduce memory protection attributes test Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 27/28] KVM: x86: selftests: Introduce memory attributes PTE test Paolo Bonzini
2026-09-18 8:15 ` [PATCH v2 28/28] KVM: x86: selftests: Introduce memory attributes side-channel tests Paolo Bonzini
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=20260918081543.139871-21-pbonzini@redhat.com \
--to=pbonzini@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=nsaenz@amazon.com \
--cc=snambakam@linux.microsoft.com \
--cc=vkuznets@redhat.com \
/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
all inboxes | Powered by JetHome®