Testing 3.6.0-rc7 with this v9 patchset plus more recent fixes [1],[2],[3] Running in a guest (qemu+seabios from [4]). CONFIG_SLAB=y CONFIG_DEBUG_SLAB=y - succesfull hot-add and online - succesfull hot-remove with SCI (qemu) eject - attempt to hot-readd same memory When the pages are re-onlined on hot-readd, I get a bad_page state for many pages e.g. [ 59.611278] init_memory_mapping: [mem 0x80000000-0x9fffffff] [ 59.637836] Built 2 zonelists in Node order, mobility grouping on. Total pages: 547617 [ 59.638739] Policy zone: Normal [ 59.650840] BUG: Bad page state in process bash pfn:9b6dc [ 59.651124] page:ffffea0002200020 count:0 mapcount:0 mapping: (null) index:0xfdfdfdfdfdfdfdfd [ 59.651494] page flags: 0x2fdfdfdfd5df9fd(locked|referenced|uptodate|dirty|lru|active|slab|owner_priv_1|private|private_2|writeback|head|tail|swapcache|reclaim|swapbacked|unevictable|uncached|compound_lock) [ 59.653604] Modules linked in: netconsole acpiphp pci_hotplug acpi_memhotplug loop kvm_amd kvm microcode tpm_tis tpm tpm_bios evdev psmouse serio_raw i2c_piix4 i2c_core parport_pc parport processor button thermal_sys ext3 jbd mbcache sg sr_mod cdrom ata_generic virtio_net ata_piix virtio_blk libata virtio_pci virtio_ring virtio scsi_mod [ 59.656998] Pid: 988, comm: bash Not tainted 3.6.0-rc7-guest #12 [ 59.657172] Call Trace: [ 59.657275] [<ffffffff810e9b30>] ? bad_page+0xb0/0x100 [ 59.657434] [<ffffffff810ea4c3>] ? free_pages_prepare+0xb3/0x100 [ 59.657610] [<ffffffff810ea668>] ? free_hot_cold_page+0x48/0x1a0 [ 59.657787] [<ffffffff8112cc08>] ? online_pages_range+0x68/0xa0 [ 59.657961] [<ffffffff8112cba0>] ? __online_page_increment_counters+0x10/0x10 [ 59.658162] [<ffffffff81045561>] ? walk_system_ram_range+0x101/0x110 [ 59.658346] [<ffffffff814c4f95>] ? online_pages+0x1a5/0x2b0 [ 59.658515] [<ffffffff8135663d>] ? __memory_block_change_state+0x20d/0x270 [ 59.658710] [<ffffffff81356756>] ? store_mem_state+0xb6/0xf0 [ 59.658878] [<ffffffff8119e482>] ? sysfs_write_file+0xd2/0x160 [ 59.659052] [<ffffffff8113769a>] ? vfs_write+0xaa/0x160 [ 59.659212] [<ffffffff81137977>] ? sys_write+0x47/0x90 [ 59.659371] [<ffffffff814e2f25>] ? async_page_fault+0x25/0x30 [ 59.659543] [<ffffffff814ea239>] ? system_call_fastpath+0x16/0x1b [ 59.659720] Disabling lock debugging due to kernel taint Patch 20/21 deals with a similar scenario, but only for __PG_HWPOISON flag. Did i miss any other patch for this? thanks, - Vasilis [1] https://lkml.org/lkml/2012/9/6/635 [2] https://lkml.org/lkml/2012/9/11/542 [3] https://lkml.org/lkml/2012/9/20/37 [4] http://permalink.gmane.org/gmane.comp.emulators.kvm.devel/98691 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>