On Thu, Sep 29, 2016 at 10:18:49PM +0200, Christoph Hellwig wrote:
> On Thu, Sep 29, 2016 at 10:18:34PM +0200, Christoph Hellwig wrote:
> > Can you try the patch below? That just moves the file_accessed call
> > before the I/O, similar to how we handle timestamp updates on the write
> > side. generic_file_read_iter will also need a similar update.
>
> And now with patch:
>
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index 349f328..6919412 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -270,6 +270,8 @@ xfs_file_dio_aio_read(
> return -EINVAL;
> }
>
> + file_accessed(iocb->ki_filp);
> +
> /*
> * Locking is a bit tricky here. If we take an exclusive lock for direct
> * IO, we effectively serialise all new concurrent read IO to this file
> @@ -324,7 +326,6 @@ xfs_file_dio_aio_read(
> }
> xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);
>
> - file_accessed(iocb->ki_filp);
> return ret;
> }
>
I noticed that g/323 only breaks when the XFS is on a real disk; on
pmem it works fine with or without the patch.
That said, it makes the crash go away and the patch looks ok, so:
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Tested-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
--D
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