On 08/02/21 21:15, Sean Christopherson wrote:
Use hva_t, a.k.a. unsigned long, for the local variable that holds the hypercall page address. On 32-bit KVM, gcc complains about using a u64 due to the implicit cast from a 64-bit value to a 32-bit pointer.arch/x86/kvm/xen.c: In function ‘kvm_xen_write_hypercall_page’: arch/x86/kvm/xen.c:300:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast] 300 | page = memdup_user((u8 __user *)blob_addr, PAGE_SIZE); Cc: Joao Martins <joao.m.mart...@oracle.com> Cc: David Woodhouse <d...@amazon.co.uk> Fixes: 23200b7a30de ("KVM: x86/xen: intercept xen hypercalls if enabled") Signed-off-by: Sean Christopherson <sea...@google.com> --- arch/x86/kvm/xen.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c index 2cee0376455c..deda1ba8c18a 100644 --- a/arch/x86/kvm/xen.c +++ b/arch/x86/kvm/xen.c @@ -286,8 +286,12 @@ int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data) return 1; } } else { - u64 blob_addr = lm ? kvm->arch.xen_hvm_config.blob_addr_64 - : kvm->arch.xen_hvm_config.blob_addr_32; + /* + * Note, truncation is a non-issue as 'lm' is guaranteed to be + * false for a 32-bit kernel, i.e. when hva_t is only 4 bytes. + */ + hva_t blob_addr = lm ? kvm->arch.xen_hvm_config.blob_addr_64 + : kvm->arch.xen_hvm_config.blob_addr_32; u8 blob_size = lm ? kvm->arch.xen_hvm_config.blob_size_64 : kvm->arch.xen_hvm_config.blob_size_32; u8 *page;
Queued, thanks. Paolo
