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Date:   Fri, 21 May 2021 14:47:36 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Nathan Lynch <nathanl@linux.ibm.com>
Cc:     linuxppc-dev@lists.ozlabs.org, mpe@ellerman.id.au,
        linux-kernel@vger.kernel.org, jirislaby@kernel.org
Subject: Re: [PATCH] powerpc/udbg_hvc: retry putc on -EAGAIN
Message-ID: <YKer6KPaHDgaWS8k@kroah.com>
References: <20210514214422.3019105-1-nathanl@linux.ibm.com>
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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 <nathanl@linux.ibm.com>
> ---
>  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