All of lore.kernel.org
 help / color / mirror / Atom feed
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Lan Tianyu <tianyu.lan@intel.com>
Cc: sstabellini@kernel.org, wei.liu2@citrix.com,
	George.Dunlap@eu.citrix.com, andrew.cooper3@citrix.com,
	ian.jackson@eu.citrix.com, jbeulich@suse.com,
	xen-devel@lists.xenproject.org
Subject: Re: [PATCH] Xen: Force non-irq keyhandler to be run in tasklet when receive a debugkey from serial port
Date: Sun, 23 Oct 2016 20:19:17 -0400	[thread overview]
Message-ID: <20161024001917.GA23896@char.us.oracle.com> (raw)
In-Reply-To: <20161022112303.11451-1-tianyu.lan@intel.com>

On Sat, Oct 22, 2016 at 07:23:03PM +0800, Lan Tianyu wrote:
> __serial_rx() runs in either irq handler or timer handler and non-irq
> keyhandler should not run in these contexts. So always force non-irq
> keyhandler to run in tasklet when receive a debugkey from serial port

If the machine is hung with an IRQ handler being stuck, and 
one does 'Ctrl-Ax3` followed by 'C' .. which would not be invoked
(as it is not an IRQ handler??


> 
> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
> ---
>  xen/drivers/char/console.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/xen/drivers/char/console.c b/xen/drivers/char/console.c
> index b0f74ce..184b523 100644
> --- a/xen/drivers/char/console.c
> +++ b/xen/drivers/char/console.c
> @@ -347,7 +347,7 @@ static void switch_serial_input(void)
>  static void __serial_rx(char c, struct cpu_user_regs *regs)
>  {
>      if ( xen_rx )
> -        return handle_keypress(c, regs, !in_irq());
> +        return handle_keypress(c, regs, true);
>  
>      /* Deliver input to guest buffer, unless it is already full. */
>      if ( (serial_rx_prod-serial_rx_cons) != SERIAL_RX_SIZE )
> -- 
> 2.9.3
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel

  reply	other threads:[~2016-10-24  0:19 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-22 11:23 [PATCH] Xen: Force non-irq keyhandler to be run in tasklet when receive a debugkey from serial port Lan Tianyu
2016-10-24  0:19 ` Konrad Rzeszutek Wilk [this message]
2016-10-24 13:29   ` Lan, Tianyu
2016-10-24 13:38     ` Konrad Rzeszutek Wilk
2016-10-24 14:12       ` Lan, Tianyu
2016-10-24 14:29         ` Jan Beulich
2016-10-24 13:54     ` Jan Beulich
2016-10-24 14:15       ` Lan, Tianyu
2016-10-24 14:31         ` Jan Beulich
2016-10-24 14:43           ` Lan, Tianyu
2016-10-24 14:56             ` Konrad Rzeszutek Wilk
2016-10-24 14:58             ` Jan Beulich
2016-10-24 10:53 ` Jan Beulich
2016-10-24 11:26   ` Wei Liu
2016-10-24 14:01   ` Lan, Tianyu
2016-10-24 14:28     ` Jan Beulich
2016-10-24 15:03       ` Lan, Tianyu
2016-10-24 15:14         ` Jan Beulich

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20161024001917.GA23896@char.us.oracle.com \
    --to=konrad.wilk@oracle.com \
    --cc=George.Dunlap@eu.citrix.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=ian.jackson@eu.citrix.com \
    --cc=jbeulich@suse.com \
    --cc=sstabellini@kernel.org \
    --cc=tianyu.lan@intel.com \
    --cc=wei.liu2@citrix.com \
    --cc=xen-devel@lists.xenproject.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.