linux-kernel - Re: [PATCH] virtio_console: Add support for multiple ports for generic guest and host communication

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 1 Oct 2009 11:00:48 +0200
From:	Christian Borntraeger <borntraeger@...ibm.com>
To:	Amit Shah <amit.shah@...hat.com>
Cc:	Rusty Russell <rusty@...tcorp.com.au>,
	Alan Cox <alan@...ux.intel.com>,
	virtualization@...ts.linux-foundation.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] virtio_console: Add support for multiple ports for generic guest and host communication

Am Mittwoch 30 September 2009 19:13:21 schrieb Amit Shah:
> - uses port->id instead of a static hvc_vtermno to pass on a value to
>   hvc_alloc(). Motivation explained within comments in the code.

[...]
> +	 * The first argument of hvc_alloc() is the virtual console
> +	 * number. hvc_alloc() checks if a console with the same value
> +	 * was used in hvc_instantiate(). We may not end up passing
> +	 * the same value here (we use the value 0 in
> +	 * hvc_instantiate() but the console port may not be at id
> +	 * 0). This isn't a problem, though. Nothing in hvc really
> +	 * depends on these numbers and since this number is passed on
> +	 * to us when cons_get/put_chars() is called, it's preferable
> +	 * to pass on the port->id so that we can get the port struct
> +	 * via get_port_from_id().
[...]
> +	port->hvc = hvc_alloc(port->id, 0, &virtio_cons, PAGE_SIZE);

I am not sure if this is going to be ok. 

When I change the old code (without your patch) to use vtermno=0 in 
hvc_instantiate and vtermno=1 in hvc_alloc I get 
"Warning: unable to open an initial console."

It seems to me that we have to pass the same values.

Christian
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/