linux-kernel - Re: [PATCH] thinkpad-acpi: setup hotkey polling after changing hotkey_driver

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: <20100209000810.GC1420@holoscopio.com>
Date:	Mon, 8 Feb 2010 22:08:10 -0200
From:	Thadeu Lima de Souza Cascardo <cascardo@...oscopio.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	linux-acpi@...r.kernel.org,
	Henrique de Moraes Holschuh <ibm-acpi@....eng.br>,
	ibm-acpi-devel@...ts.sourceforge.net, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] thinkpad-acpi: setup hotkey polling after changing
 hotkey_driver_mask

On Mon, Feb 08, 2010 at 03:50:59PM -0800, Andrew Morton wrote:
> On Sun,  7 Feb 2010 16:32:07 -0200
> Thadeu Lima de Souza Cascardo <cascardo@...oscopio.com> wrote:
> 
> > Brightness notification does not work until the user writes to
> > hotkey_mask attribute. That's because the polling thread will only run
> > if hotkey_user_mask is set and someone is reading the input device or if
> > hotkey_driver_mask is set. In this second case, this condition is not
> > tested after the mask is changed, because the brightness and volume
> > drivers are started after the hotkey drivers.
> > 
> > This fix test for the polling condition that ends up starting the
> > polling thread after hotkey_driver_mask is set in brightness and volume
> > init functions.
> > 
> > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@...oscopio.com>
> > ---
> >  drivers/platform/x86/thinkpad_acpi.c |    9 +++++++++
> >  1 files changed, 9 insertions(+), 0 deletions(-)
> > 
> > diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
> > index e67e4fe..d69749d 100644
> > --- a/drivers/platform/x86/thinkpad_acpi.c
> > +++ b/drivers/platform/x86/thinkpad_acpi.c
> > @@ -6272,6 +6272,11 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
> >  	tpacpi_hotkey_driver_mask_set(hotkey_driver_mask
> >  				| TP_ACPI_HKEY_BRGHTUP_MASK
> >  				| TP_ACPI_HKEY_BRGHTDWN_MASK);;
> > +
> > +#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
> > +	hotkey_poll_setup(true);
> > +#endif
> > +
> >  	return 0;
> >  }
> >  
> > @@ -6903,6 +6908,10 @@ static int __init volume_init(struct ibm_init_struct *iibm)
> >  			| TP_ACPI_HKEY_VOLDWN_MASK
> >  			| TP_ACPI_HKEY_MUTE_MASK);
> >  
> > +#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
> > +	hotkey_poll_setup(true);
> > +#endif
> > +
> >  	return 0;
> >  }
> 
> Something like this is needed, methinks:
> 
> - Avoid ifdefs
> 
> - Make sure that hotkey_mutex is held when calling hotkey_poll_setup:
>   use hotkey_poll_setup_safe.  Doesn't matter much in __init code.
> 
> --- a/drivers/platform/x86/thinkpad_acpi.c~thinkpad-acpi-setup-hotkey-polling-after-changing-hotkey_driver_mask-fix
> +++ a/drivers/platform/x86/thinkpad_acpi.c
> @@ -2597,6 +2597,10 @@ static void hotkey_poll_set_freq(unsigne
>  
>  #else /* CONFIG_THINKPAD_ACPI_HOTKEY_POLL */
>  
> +static void hotkey_poll_setup(bool __unused)
> +{
> +}
> +
>  static void hotkey_poll_setup_safe(bool __unused)
>  {
>  }
> @@ -2694,9 +2698,7 @@ static ssize_t hotkey_mask_store(struct 
>  
>  	res = hotkey_user_mask_set(t);
>  
> -#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
>  	hotkey_poll_setup(true);
> -#endif
>  
>  	mutex_unlock(&hotkey_mutex);
>  
> @@ -6273,9 +6275,7 @@ static int __init brightness_init(struct
>  				| TP_ACPI_HKEY_BRGHTUP_MASK
>  				| TP_ACPI_HKEY_BRGHTDWN_MASK);;
>  
> -#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
> -	hotkey_poll_setup(true);
> -#endif
> +	hotkey_poll_setup_safe(true);
>  
>  	return 0;
>  }
> _
> 

How about the added call to volume_init?

Regards,
Cascardo.

Download attachment "signature.asc" of type "application/pgp-signature" (199 bytes)