Re: [PATCH 1/2] migration/compress: compress QEMUFile is not writable

[Wei Yang <richardw.yang@linux.intel.com>]

On Thu, Nov 07, 2019 at 11:59:10AM +0000, Dr. David Alan Gilbert wrote:
>* Wei Yang (richardw.yang@linux.intel.com) wrote:
>> We open a file with empty_ops for compress QEMUFile, which means this is
>> not writable.
>
>That explanation sounds reasonable; but I'm confused by the history of
>this;  the code was added by Liang Li in :
>
>  b3be289 qemu-file: Fix qemu_put_compression_data flaw
>
>  ( https://www.mail-archive.com/qemu-devel@nongnu.org/msg368974.html )
>
>with almost exactly the opposite argument;  can we figure out why?
>

Hmm... sounds interesting.

Toke a look into the change log, which says

    Current qemu_put_compression_data can only work with no writable
    QEMUFile, and can't work with the writable QEMUFile. But it does
    not provide any measure to prevent users from using it with a
    writable QEMUFile.

    We should fix this flaw to make it works with writable QEMUFile.

While I don't see a chance to use writable QEMUFile. Do I miss something?

>Dave
>

-- 
Wei Yang
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