lkml.org 
[lkml]   [2016]   [Nov]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.8 11/92] s390/hypfs: Use get_free_page() instead of kmalloc to ensure page alignment
    Date
    4.8-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Michael Holzheu <holzheu@linux.vnet.ibm.com>

    commit 237d6e6884136923b6bd26d5141ebe1d065960c9 upstream.

    Since commit d86bd1bece6f ("mm/slub: support left redzone") it is no longer
    guaranteed that kmalloc(PAGE_SIZE) returns page aligned memory.

    After the above commit we get an error for diag224 because aligned
    memory is required. This leads to the following user visible error:

    # mount none -t s390_hypfs /sys/hypervisor/
    mount: unknown filesystem type 's390_hypfs'

    # dmesg | grep hypfs
    hypfs.cccfb8: The hardware system does not provide all functions
    required by hypfs
    hypfs.7a79f0: Initialization of hypfs failed with rc=-61

    Fix this problem and use get_free_page() instead of kmalloc() to get
    correctly aligned memory.

    Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
    Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    arch/s390/hypfs/hypfs_diag.c | 6 +++---
    1 file changed, 3 insertions(+), 3 deletions(-)

    --- a/arch/s390/hypfs/hypfs_diag.c
    +++ b/arch/s390/hypfs/hypfs_diag.c
    @@ -363,11 +363,11 @@ out:
    static int diag224_get_name_table(void)
    {
    /* memory must be below 2GB */
    - diag224_cpu_names = kmalloc(PAGE_SIZE, GFP_KERNEL | GFP_DMA);
    + diag224_cpu_names = (char *) __get_free_page(GFP_KERNEL | GFP_DMA);
    if (!diag224_cpu_names)
    return -ENOMEM;
    if (diag224(diag224_cpu_names)) {
    - kfree(diag224_cpu_names);
    + free_page((unsigned long) diag224_cpu_names);
    return -EOPNOTSUPP;
    }
    EBCASC(diag224_cpu_names + 16, (*diag224_cpu_names + 1) * 16);
    @@ -376,7 +376,7 @@ static int diag224_get_name_table(void)

    static void diag224_delete_name_table(void)
    {
    - kfree(diag224_cpu_names);
    + free_page((unsigned long) diag224_cpu_names);
    }

    static int diag224_idx2name(int index, char *name)

    \
     
     \ /
      Last update: 2016-11-17 12:07    [W:6.278 / U:0.000 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site