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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2026 21:36:12.3188 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 2abfdd1b-d14e-4c68-8a1e-08de52ebc5dd X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN2PEPF0000449E.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH1PPFF5B95D789 On Tue, Jan 13, 2026 at 11:21:29AM -0800, Sean Christopherson wrote: > On Thu, Jan 08, 2026, Michael Roth wrote: > > @@ -842,47 +881,38 @@ long kvm_gmem_populate(struct kvm *kvm, gfn_t start_gfn, void __user *src, long > > if (!file) > > return -EFAULT; > > > > - filemap_invalidate_lock(file->f_mapping); > > - > > npages = min_t(ulong, slot->npages - (start_gfn - slot->base_gfn), npages); > > for (i = 0; i < npages; i++) { > > - struct folio *folio; > > - gfn_t gfn = start_gfn + i; > > - pgoff_t index = kvm_gmem_get_index(slot, gfn); > > - kvm_pfn_t pfn; > > + struct page *src_page = NULL; > > + void __user *p; > > > > if (signal_pending(current)) { > > ret = -EINTR; > > break; > > } > > > > - folio = __kvm_gmem_get_pfn(file, slot, index, &pfn, NULL); > > - if (IS_ERR(folio)) { > > - ret = PTR_ERR(folio); > > - break; > > - } > > + p = src ? src + i * PAGE_SIZE : NULL; > > > > - folio_unlock(folio); > > + if (p) { > > Computing 'p' when src==NULL is unnecessary and makes it hard to see that gup() > is done if and only if src!=NULL. > > Anyone object to this fixup? No objections here, and it does seem a bit more readable. Will include this if a new version is needed. Thanks, Mike > > diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c > index 18ae59b92257..66afab8f08a3 100644 > --- a/virt/kvm/guest_memfd.c > +++ b/virt/kvm/guest_memfd.c > @@ -884,17 +884,16 @@ long kvm_gmem_populate(struct kvm *kvm, gfn_t start_gfn, void __user *src, long > npages = min_t(ulong, slot->npages - (start_gfn - slot->base_gfn), npages); > for (i = 0; i < npages; i++) { > struct page *src_page = NULL; > - void __user *p; > > if (signal_pending(current)) { > ret = -EINTR; > break; > } > > - p = src ? src + i * PAGE_SIZE : NULL; > + if (src) { > + unsigned long uaddr = (unsigned long)src + i * PAGE_SIZE; > > - if (p) { > - ret = get_user_pages_fast((unsigned long)p, 1, 0, &src_page); > + ret = get_user_pages_fast(uaddr, 1, 0, &src_page); > if (ret < 0) > break; > if (ret != 1) { > > To end up with: > > struct page *src_page = NULL; > > if (signal_pending(current)) { > ret = -EINTR; > break; > } > > if (src) { > unsigned long uaddr = (unsigned long)src + i * PAGE_SIZE; > > ret = get_user_pages_fast(uaddr, 1, 0, &src_page); > if (ret < 0) > break; > if (ret != 1) { > ret = -ENOMEM; > break; > } > } > > ...