• Dan Williams's avatar
    libnvdimm, pfn: fix memmap reservation size versus 4K alignment · cd755677
    Dan Williams authored
    commit bfb34527 upstream.
    
    When vmemmap_populate() allocates space for the memmap it does so in 2MB
    sized chunks. The libnvdimm-pfn driver incorrectly accounts for this
    when the alignment of the device is set to 4K. When this happens we
    trigger memory allocation failures in altmap_alloc_block_buf() and
    trigger warnings of the form:
    
     WARNING: CPU: 0 PID: 3376 at arch/x86/mm/init_64.c:656 arch_add_memory+0xe4/0xf0
     [..]
     Call Trace:
      dump_stack+0x86/0xc3
      __warn+0xcb/0xf0
      warn_slowpath_null+0x1d/0x20
      arch_add_memory+0xe4/0xf0
      devm_memremap_pages+0x29b/0x4e0
    
    Fixes: 315c5625 ("libnvdimm, pfn: add 'align' attribute, default to HPAGE_SIZE")
    Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    cd755677
pfn_devs.c 17.5 KB