From: Jordan Niethe > Sent: 07 August 2023 02:46 > > The LPID register is 32 bits long. The host keeps the lpids for each > guest in an unsigned word struct kvm_arch. Currently, LPIDs are already > limited by mmu_lpid_bits and KVM_MAX_NESTED_GUESTS_SHIFT. > > The nestedv2 API returns a 64 bit "Guest ID" to be used be the L1 host > for each L2 guest. This value is used as an lpid, e.g. it is the > parameter used by H_RPT_INVALIDATE. To minimize needless special casing > it makes sense to keep this "Guest ID" in struct kvm_arch::lpid. > > This means that struct kvm_arch::lpid is too small so prepare for this > and make it an unsigned long. This is not a problem for the KVM-HV and > nestedv1 cases as their lpid values are already limited to valid ranges > so in those contexts the lpid can be used as an unsigned word safely as > needed. Shouldn't it be changed to u64? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
