lkml.org 
[lkml]   [2018]   [Jun]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Date
    SubjectRe: [PATCH 1/6] ext4: sysfs: print ext4_super_block fields as little-endian
    On Thu, Jun 21, 2018 at 7:49 PM, Andreas Dilger <adilger@dilger.ca> wrote:
    > On Jun 20, 2018, at 9:32 AM, Arnd Bergmann <arnd@arndb.de> wrote:
    >>
    >> While working on extended rand for last_error/first_error timestamps,
    >> I noticed that the endianess is wrong, we access the little-endian
    >> fields in struct ext4_super_block as native-endian when we print them.
    >>
    >> This adds a special case in ext4_attr_show() and ext4_attr_store()
    >> to byteswap the superblock fields if needed.
    >>
    >> In older kernels, this code was part of super.c, it got moved to sysfs.c
    >> in linux-4.4.
    >>
    >> Cc: stable@vger.kernel.org
    >> Fixes: 52c198c6820f ("ext4: add sysfs entry showing whether the fs contains errors")
    >> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
    >
    > I was wondering why this didn't just use le32_to_cpu() all the time,
    > but I see that these functions are being used for both ext4_super_block
    > (on-disk) fields, as well as ext4_sb_info (in-memory) fields. A bit
    > ugly, but I don't think there is a better solution.
    >
    > Reviewed-by: Andreas Dilger <adilger@dilger.ca>

    One alternative that I considered was to just do away with helpers
    for the ext4_super_block structure and only use them for ext4_sb_info,
    especially after the last patch that changes this again. However,
    as a bugfix for stable backports it seemed best to keep the change
    as simple as possible.

    Thanks for the review,

    Arnd

    \
     
     \ /
      Last update: 2018-06-21 22:07    [W:4.278 / U:0.244 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site