Re: [Qemu-devel] [PATCH v2 1/2] fw_cfg: document fw_cfg_modify_iXX() update functions

[Laszlo Ersek <lersek@redhat.com>]

On 08/06/15 01:47, Gabriel L. Somlo wrote:
> Document the behavior of fw_cfg_modify_iXX() for leak-free update
> of integer fw_cfg blobs; this function was added as a bug fix with
> commit 48779e501810c5046ff8af7b9cf9c99bec2928a1.
> 
> Currently only fw_cfg_modify_i16() is coded, but 32- and 64-bit
> versions may be added later if necessary.
> 
> Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
> ---
>  docs/specs/fw_cfg.txt | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt
> index 74351dd..5bc7b96 100644
> --- a/docs/specs/fw_cfg.txt
> +++ b/docs/specs/fw_cfg.txt
> @@ -159,6 +159,17 @@ will convert a 16-, 32-, or 64-bit integer to little-endian, then add
>  a dynamically allocated copy of the appropriately sized item to fw_cfg
>  under the given selector key value.
>  
> +== fw_cfg_modify_iXX() ==
> +
> +Modify the value of an XX-bit item (where XX may be 16, 32, or 64).
> +Similarly to the corresponding fw_cfg_add_iXX() function set, convert
> +a 16-, 32-, or 64-bit integer to little endian, create a dynamically
> +allocated copy of the required size, and replace the existing item at
> +the given selector key value with the newly allocated one. The previous
> +item, assumed to have been allocated during an earlier call to
> +fw_cfg_add_iXX() or fw_cfg_modify_iXX() (of the same width XX), is freed
> +before the function returns.
> +
>  == fw_cfg_add_file() ==
>  
>  Given a filename (i.e., fw_cfg item name), starting pointer, and size,
> 

I think I gave my R-b for this here:

http://thread.gmane.org/gmane.comp.emulators.qemu/352278/focus=352299