• Anton Blanchard's avatar
    powerpc: Fix oops when echoing bad values to /sys/devices/system/memory/probe · a1194097
    Anton Blanchard authored
    If we echo an address the hypervisor doesn't like to
    /sys/devices/system/memory/probe we oops the box:
    
    # echo 0x10000000000 > /sys/devices/system/memory/probe
    
    kernel BUG at arch/powerpc/mm/hash_utils_64.c:541!
    
    The backtrace is:
    
    create_section_mapping
    arch_add_memory
    add_memory
    memory_probe_store
    sysdev_class_store
    sysfs_write_file
    vfs_write
    SyS_write
    
    In create_section_mapping we BUG if htab_bolt_mapping returned
    an error. A better approach is to return an error which will
    propagate back to userspace.
    
    Rerunning the test with this patch applied:
    
    # echo 0x10000000000 > /sys/devices/system/memory/probe
    -bash: echo: write error: Invalid argument
    Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
    Cc: stable@kernel.org
    Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
    a1194097
mem.c 15.2 KB