All of lore.kernel.org
 help / color / mirror / Atom feed
* FAILED: patch "[PATCH] KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said" failed to apply to 6.18-stable tree
@ 2026-09-29 11:38 gregkh
  2026-09-30 15:09 ` [PATCH 6.18.y 1/5] KVM: x86: Move IRQ-related helper declarations from kvm_host.h => irq.h Sasha Levin
  0 siblings, 1 reply; 6+ messages in thread
From: gregkh @ 2026-09-29 11:38 UTC (permalink / raw)
  To: seanjc, fane, rkskek9254; +Cc: stable


The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 10180a277549339020b08000206092c07e0bff5a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026092945-breath-candle-8e2c@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 10180a277549339020b08000206092c07e0bff5a Mon Sep 17 00:00:00 2001
From: Sean Christopherson <seanjc@google.com>
Date: Mon, 21 Sep 2026 14:16:07 -0700
Subject: [PATCH] KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said
 pages fails

Re-pend GET_NESTED_STATE_PAGES before exiting to userspace if getting the
nested pages fails in the KVM_RUN path.  If userspace re-runs the vCPU, and
vmcs02 holds valid PFNs from the *previous* run of L2, then KVM could
re-enter L2 with stale, unpinned PFNs mapped into e.g. the vAPIC page.

Note, both SVM and VMX (as of commit 11722439fb20 ("KVM: nVMX: Ensure
KVM_REQ_GET_NESTED_STATE_PAGES is cleared on VM-Exit") ensure the request
is cleared on VM-Exit (including the "forced" case), i.e. there is no risk
of double-mapping due to emulated VMLAUNCH/VMRESUME/VMRUN *and* the request
trying to map the nested pages.

Fixes: 671ddc700fd0 ("KVM: nVMX: Don't leak L1 MMIO regions to L2")
Cc: stable@vger.kernel.org
Reported-by: Jinwoo Lee <rkskek9254@gmail.com>
Closes: https://lore.kernel.org/all/20260813043932.3214460-1-rkskek9254@gmail.com
Reported-by: Stefan Teodorescu <fane@google.com>
Link: https://patch.msgid.link/20260921211608.1030158-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a137dc6dd8c6..4ec17aaff413 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8072,6 +8072,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 
 		if (kvm_check_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu)) {
 			if (unlikely(!kvm_nested_call(get_nested_state_pages)(vcpu))) {
+				kvm_make_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
 				r = 0;
 				goto out;
 			}


^ permalink raw reply related	[flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-09-30 15:10 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-09-29 11:38 FAILED: patch "[PATCH] KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said" failed to apply to 6.18-stable tree gregkh
2026-09-30 15:09 ` [PATCH 6.18.y 1/5] KVM: x86: Move IRQ-related helper declarations from kvm_host.h => irq.h Sasha Levin
2026-09-30 15:09   ` [PATCH 6.18.y 2/5] KVM: move TSS constants from kvm_host.h to tss.h Sasha Levin
2026-09-30 15:09   ` [PATCH 6.18.y 3/5] KVM: x86: Reject nested CAP enablement if nested virtualization is disabled Sasha Levin
2026-09-30 15:09   ` [PATCH 6.18.y 4/5] KVM: x86: Add static calls for nested virtualization ops Sasha Levin
2026-09-30 15:09   ` [PATCH 6.18.y 5/5] KVM: x86: Re-pend GET_NESTED_STATE_PAGES if getting said pages fails Sasha Levin

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.