# Re: \[PATCH\] powerpc/udbg\_hvc: retry putc on -EAGAIN

- From: Greg KH \<gregkh@linuxfoundation.org\>
- Date: 2021-05-21 12:47:45 
- List: linuxppc-dev
- Page: https://ratatoskr.run/linuxppc-dev/2021/05/1387462
- Thread: https://ratatoskr.run/linuxppc-dev/2021/05/1378232/t.md

```text
On Fri, May 14, 2021 at 04:44:22PM -0500, Nathan Lynch wrote:
> hvterm_raw_put_chars() calls hvc_put_chars(), which may return -EAGAIN
> when the underlying hcall returns a "busy" status, but udbg_hvc_putc()
> doesn't handle this. When using xmon on a PowerVM guest, this can
> result in incomplete or garbled output when printing relatively large
> amounts of data quickly, such as when dumping the kernel log buffer.
> 
> Call again on -EAGAIN.
> 
> Signed-off-by: Nathan Lynch <redacted>
> ---
>  drivers/tty/hvc/hvc_vio.c | 2 +-

Subject line does not match up with this file name.

Don't you want "tty" and "hvc" in there somewhere?

thanks,

greg k-h
```