github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-28 17:13:52 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

KVM: arm64: Fix vma_shift staleness on nested hwpoison path

Browse Source 
When user_mem_abort() handles a nested stage-2 fault, it truncates
vma_pagesize to respect the guest's mapping size. However, the local
variable vma_shift is never updated to match this new size.

If the underlying host page turns out to be hardware poisoned,
kvm_send_hwpoison_signal() is called with the original, larger
vma_shift instead of the actual mapping size. This signals incorrect
poison boundaries to userspace and breaks hugepage memory poison
containment for nested VMs.

Update vma_shift to match the truncated vma_pagesize when operating
on behalf of a nested hypervisor.

Fixes: fd276e71d1 ("KVM: arm64: nv: Handle shadow stage 2 page faults")
Signed-off-by: Fuad Tabba <tabba@google.com>
Link: https://patch.msgid.link/20260304162222.836152-3-tabba@google.com
[maz: simplified vma_shift assignment from the original patch]
Signed-off-by: Marc Zyngier <maz@kernel.org>
This commit is contained in:
Fuad Tabba 2026-03-04 16:22:22 +00:00 committed by Marc Zyngier
parent e07fc9e2da
commit 244acf1976
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
arch/arm64/kvm/mmu.c
View File

@ -1751,6 +1751,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
force_pte = (max_map_size == PAGE_SIZE);
vma_pagesize = min_t(long, vma_pagesize, max_map_size);
vma_shift = __ffs(vma_pagesize);
}
/*