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charset="us-ascii" On Tue, Oct 20, 2026, Christian Borntraeger wrote: > hva_to_pfn() checks a FOLL_NOWAIT gup() for EINTR, EAGAIN and EHWPOISON. > There might be others like -EFAULT for VM_FAULT_SIGBUS. For those other > errors, reporting KVM_PFN_ERR_NEEDS_IO would be wrong as it triggers an > async_pf resulting in endless retries. > > Return KVM_PFN_ERR_NEEDS_IO only if gup() returned 0 pages and report > the error otherwise. > > Fixes: 0857b9e95c1a ("KVM: Enable async page fault processing") > Signed-off-by: Christian Borntraeger > --- Reviewed-by: Sean Christopherson