diff options
| author | Sean Christopherson <seanjc@google.com> | 2025-01-23 15:46:13 +0100 |
|---|---|---|
| committer | Claudio Imbrenda <imbrenda@linux.ibm.com> | 2025-01-31 12:03:52 +0100 |
| commit | 66119f8ce135de664cb2fb88d9aaa322d7451a1f (patch) | |
| tree | 50470d864ff0792705872d040075d4aea5470065 /virt | |
| parent | 4514eda4c1dbd0b7062e06c769d2ceafd25c9284 (diff) | |
KVM: Do not restrict the size of KVM-internal memory regions
Exempt KVM-internal memslots from the KVM_MEM_MAX_NR_PAGES restriction, as
the limit on the number of pages exists purely to play nice with dirty
bitmap operations, which use 32-bit values to index the bitmaps, and dirty
logging isn't supported for KVM-internal memslots.
Link: https://lore.kernel.org/all/20240802205003.353672-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20250123144627.312456-2-imbrenda@linux.ibm.com
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20250123144627.312456-2-imbrenda@linux.ibm.com>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/kvm_main.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index faf10671eed2..3f04cd5e3a8c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1971,7 +1971,15 @@ static int kvm_set_memory_region(struct kvm *kvm, return -EINVAL; if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr) return -EINVAL; - if ((mem->memory_size >> PAGE_SHIFT) > KVM_MEM_MAX_NR_PAGES) + + /* + * The size of userspace-defined memory regions is restricted in order + * to play nice with dirty bitmap operations, which are indexed with an + * "unsigned int". KVM's internal memory regions don't support dirty + * logging, and so are exempt. + */ + if (id < KVM_USER_MEM_SLOTS && + (mem->memory_size >> PAGE_SHIFT) > KVM_MEM_MAX_NR_PAGES) return -EINVAL; slots = __kvm_memslots(kvm, as_id); |