linux-kernel - Re: [PATCH] Serial: BUGFIX: uart_resume

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]

Message-ID: <AANLkTimc-ETu4zrny=kmVRq8jnh2CDiVSqE-EXde4ioS@mail.gmail.com>
Date:	Wed, 13 Oct 2010 15:38:13 +0900
From:	MyungJoo Ham <myungjoo.ham@...sung.com>
To:	Greg KH <gregkh@...e.de>
Cc:	linux-kernel@...r.kernel.org, kyungmin.park@...sung.com,
	Alan Cox <alan@...ux.intel.com>, Arnd Bergmann <arnd@...db.de>,
	Andr Goddard Rosa <andre.goddard@...il.com>,
	Stanislav Brabec <sbrabec@...e.cz>
Subject: Re: [PATCH] Serial: BUGFIX: uart_resume_port has an omitted condition.

On Wed, Oct 13, 2010 at 3:26 PM, Greg KH <gregkh@...e.de> wrote:
> On Wed, Oct 13, 2010 at 02:58:06PM +0900, MyungJoo Ham wrote:
>> When console_suspend_enabled == 0, console_stop() was not called at
>> suspend; thus, it does not need to call console_start() when resume.
>> Besides, calling console_start() without calling console_stop() before
>> had been incurring kernel hang with console_suspend_enabled == 0 in a
>> machine with drivers/serial/samsung.c and s5pc210.
>
> Is this a regression?  If so, from what working kernel?  Or has this
> always been this way?
>
> thanks,
>
> greg k-h
>


I don't think this is a regression to the previous version. Logically,
it's matching the console_stop()-console_start() pair.

Such hang in serial and its mitigation is observed in 2.6.36 at
arch/arm/mach-s5pv310 machines. In these machines, it hanged with
console_suspend_enabled == 0 every time.



Cheers!

- MyungJoo

-- 
MyungJoo Ham (함명주), Ph.D.
Mobile Software Platform Lab,
Digital Media and Communications (DMC) Business
Samsung Electronics
cell: 82-10-6714-2858
--
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/