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:	Sun, 20 May 2007 23:12:18 -0400
From:	Dmitry Torokhov <dtor@...ightbb.com>
To:	Pierre Ossman <drzeus-list@...eus.cx>
Cc:	Greg KH <greg@...ah.com>, LKML <linux-kernel@...r.kernel.org>
Subject: Re: Race free attributes in sysfs

On Sunday 20 May 2007 07:01, Pierre Ossman wrote:
> Hi Greg,
> 
> I'm reworking the sysfs stuff in the MMC layer to be a bit more flexible, but
> there is one thing that has me baffled; how do you add attributes to an object
> in a race free manner when you have a dynamic set of attributes.
> 
> I've looked at other parts of the kernel and they all use:
> 
> 1. Add object.
> 2. Add attributes.
> 
> To me, it seems like there's a window between 1 and 2 where the object is in
> /sys but doesn't have the proper attributes. Life for user space gets very
> annoying if it has to add artificial delays to avoid this window.
> 
> So how do I do this properly? Something like this would, from my point of view,
> be the sane method:
> 
> 1. Add hidden object.
> 2. Add attributes.
> 3. Show object.
> 

1. dev->uevent_suppress = 1;
2. device_register(dev);
3. device_create_file(dev, ...);
4. dev->uevent_suppress = 0;
5. kobject_uevent(&dev->kobj, KOBJ_ADD);

-- 
Dmitry
-
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/

Powered by blists - more mailing lists