The patch titled Subject: virtio-mem: mark device ready before registering callbacks in kdump mode has been added to the -mm mm-unstable branch. Its filename is virtio-mem-mark-device-ready-before-registering-callbacks-in-kdump-mode.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/virtio-mem-mark-device-ready-before-registering-callbacks-in-kdump-mode.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: David Hildenbrand <david@xxxxxxxxxx> Subject: virtio-mem: mark device ready before registering callbacks in kdump mode Date: Wed, 4 Dec 2024 13:54:40 +0100 After the callbacks are registered we may immediately get a callback. So mark the device ready before registering the callbacks. Link: https://lkml.kernel.org/r/20241204125444.1734652-10-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> Cc: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> Cc: Cornelia Huck <cohuck@xxxxxxxxxx> Cc: Dave Young <dyoung@xxxxxxxxxx> Cc: Eric Farman <farman@xxxxxxxxxxxxx> Cc: Eugenio Pérez <eperezma@xxxxxxxxxx> Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> Cc: Janosch Frank <frankja@xxxxxxxxxxxxx> Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx> Cc: Sven Schnelle <svens@xxxxxxxxxxxxx> Cc: Thomas Huth <thuth@xxxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Vivek Goyal <vgoyal@xxxxxxxxxx> Cc: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/virtio/virtio_mem.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/virtio/virtio_mem.c~virtio-mem-mark-device-ready-before-registering-callbacks-in-kdump-mode +++ a/drivers/virtio/virtio_mem.c @@ -2648,6 +2648,7 @@ static int virtio_mem_init_hotplug(struc if (rc) goto out_unreg_pm; + virtio_device_ready(vm->vdev); return 0; out_unreg_pm: unregister_pm_notifier(&vm->pm_notifier); @@ -2729,6 +2730,8 @@ static bool virtio_mem_vmcore_pfn_is_ram static int virtio_mem_init_kdump(struct virtio_mem *vm) { + /* We must be prepared to receive a callback immediately. */ + virtio_device_ready(vm->vdev); #ifdef CONFIG_PROC_VMCORE dev_info(&vm->vdev->dev, "memory hot(un)plug disabled in kdump kernel\n"); vm->vmcore_cb.pfn_is_ram = virtio_mem_vmcore_pfn_is_ram; @@ -2870,8 +2873,6 @@ static int virtio_mem_probe(struct virti if (rc) goto out_del_vq; - virtio_device_ready(vdev); - /* trigger a config update to start processing the requested_size */ if (!vm->in_kdump) { atomic_set(&vm->config_changed, 1); _ Patches currently in -mm which might be from david@xxxxxxxxxx are mm-mempolicy-fix-migrate_to_node-assuming-there-is-at-least-one-vma-in-a-mm.patch mm-filemap-dont-call-folio_test_locked-without-a-reference-in-next_uptodate_folio.patch docs-tmpfs-update-the-large-folios-policy-for-tmpfs-and-shmem.patch mm-memory_hotplug-move-debug_pagealloc_map_pages-into-online_pages_range.patch mm-page_isolation-dont-pass-gfp-flags-to-isolate_single_pageblock.patch mm-page_isolation-dont-pass-gfp-flags-to-start_isolate_page_range.patch mm-page_alloc-make-__alloc_contig_migrate_range-static.patch mm-page_alloc-sort-out-the-alloc_contig_range-gfp-flags-mess.patch mm-page_alloc-forward-the-gfp-flags-from-alloc_contig_range-to-post_alloc_hook.patch powernv-memtrace-use-__gfp_zero-with-alloc_contig_pages.patch mm-hugetlb-dont-map-folios-writable-without-vm_write-when-copying-during-fork.patch fs-proc-vmcore-convert-vmcore_cb_lock-into-vmcore_mutex.patch fs-proc-vmcore-replace-vmcoredd_mutex-by-vmcore_mutex.patch fs-proc-vmcore-disallow-vmcore-modifications-while-the-vmcore-is-open.patch fs-proc-vmcore-prefix-all-pr_-with-vmcore.patch fs-proc-vmcore-move-vmcore-definitions-out-of-kcoreh.patch fs-proc-vmcore-factor-out-allocating-a-vmcore-range-and-adding-it-to-a-list.patch fs-proc-vmcore-factor-out-freeing-a-list-of-vmcore-ranges.patch fs-proc-vmcore-introduce-proc_vmcore_device_ram-to-detect-device-ram-ranges-in-2nd-kernel.patch virtio-mem-mark-device-ready-before-registering-callbacks-in-kdump-mode.patch virtio-mem-remember-usable-region-size.patch virtio-mem-support-config_proc_vmcore_device_ram.patch s390-kdump-virtio-mem-kdump-support-config_proc_vmcore_device_ram.patch