Re: [PATCH] ptp: ocp: Add newline to sysfs attribute output

[Vadim Fedorenko]

On 31/10/2025 23:59, Jakub Kicinski wrote:
> On Thu, 30 Oct 2025 20:45:19 +0800 Zhongqiu Han wrote:
> > Append a newline character to the sysfs_emit() output in ptp_ocp_tty_show.
> > This aligns with common kernel conventions and improves readability for
> > userspace tools that expect newline-terminated values.
>
> Vadim? Is the backward compat here a concern?

Well, unfortunately, this patch breaks software we use:

openat(AT_FDCWD, "/dev/ttyS4\n", O_RDWR|O_NONBLOCK) = -1 ENOENT (No such 
file or directory)
newfstatat(AT_FDCWD, "/etc/localtime", {st_mode=S_IFREG|0644, 
st_size=114, ...}, 0) = 0
write(2, "23:40:33 \33[31mERROR\33[0m ", 2423:40:33 ERROR ) = 24
write(2, "Could not open sa5x device\n", 27Could not open sa5x device

So it looks like uAPI change, which is already used...