Re: [PATCH v8 19/46] KVM: guest_memfd: Use actual size for invalidation in kvm_gmem_release()
From: Fuad Tabba <hidden>
Date: 2026-06-19 10:46:45
Also in:
kvm, linux-coco, linux-doc, linux-kselftest, linux-mm, lkml
On Fri, 19 Jun 2026 at 01:31, Ackerley Tng via B4 Relay [off-list ref] wrote:
From: Ackerley Tng <redacted> __kvm_gmem_invalidate_begin() and __kvm_gmem_invalidate_end() actually do not specially handle -1ul. -1ul is used as a huge number, which legal indices do not exceed, and hence the invalidation works as expected. Since a later patch is going to make use of the exact range, calculate the size of the guest_memfd inode and use it as the end range for invalidating SPTEs. Signed-off-by: Ackerley Tng <redacted> ---
Reviewed-by: Fuad Tabba <redacted> Cheers, /fuad
quoted hunk ↗ jump to hunk
virt/kvm/guest_memfd.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index d163559da0235..d72ecbfcc3144 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c@@ -366,6 +366,7 @@ static long kvm_gmem_fallocate(struct file *file, int mode, loff_t offset, static int kvm_gmem_release(struct inode *inode, struct file *file) { + pgoff_t end = i_size_read(inode) >> PAGE_SHIFT; struct gmem_file *f = file->private_data; struct kvm_memory_slot *slot; struct kvm *kvm = f->kvm;@@ -396,9 +397,9 @@ static int kvm_gmem_release(struct inode *inode, struct file *file) * Zap all SPTEs pointed at by this file. Do not free the backing * memory, as its lifetime is associated with the inode, not the file. */ - __kvm_gmem_invalidate_start(f, 0, -1ul, + __kvm_gmem_invalidate_start(f, 0, end, kvm_gmem_get_invalidate_filter(inode)); - __kvm_gmem_invalidate_end(f, 0, -1ul); + __kvm_gmem_invalidate_end(f, 0, end); list_del(&f->entry); --2.55.0.rc0.738.g0c8ab3ebcc-goog