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charset=US-ASCII X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alsa-devel@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" On Sat, 04 Feb 2023 01:55:27 +0100, Takashi Sakamoto wrote: > > Hi, > > On Fri, Feb 03, 2023 at 05:22:40PM +0100, Takashi Iwai wrote: > > On Thu, 02 Feb 2023 14:37:08 +0100, > > Takashi Sakamoto wrote: > > > > > > Current structure includes no field to express the number of messages > > > copied to user space, thus user space application needs to information > > > out of the structure to parse the content of structure. > > > > > > This commit adds a field to express the number of messages copied to user > > > space since It is more preferable to use self-contained structure. > > > > > > Kees Cook proposed an idea of annotation for bound of flexible arrays > > > in his future improvement for flexible-length array in kernel. The > > > additional field for message count is suitable to the idea as well. > > > > > > Reference: https://people.kernel.org/kees/bounded-flexible-arrays-in-c > > > Signed-off-by: Takashi Sakamoto > > > > Wouldn't changing this break the existing application that talks with > > the older ABI? Just to be sure... > > You may well have the concern, indeed. > > The structure is not exposed to user space yet, since it was added by a > commit ab811cfffa9 ("ALSA: fireface: update UAPI for data of knob > control"). It just exists in your (and mine) tree at present. Ah I see, then that's OK, better to change now. Applied now to for-next branch. thanks, Takashi