On Tue, Sep 20, 2011 at 09:46:08PM +0000, Florian Tobias Schandinat wrote: > Hi Andrew, > > On 09/20/2011 09:11 PM, akpm@xxxxxxxxxx wrote: > > From: Andrea Righi <arighi@xxxxxxxxxxx> > > Subject: fb: fix potential deadlock between lock_fb_info and console_lock > > > > fb_set_suspend() must be called with the console semaphore held, which > > means the code path coming in here will first take the console_lock() and > > then call lock_fb_info(). > > > > However several framebuffer ioctl commands acquire these locks in reverse > > order (lock_fb_info() and then console_lock()). This gives rise to > > potential AB-BA deadlock. > > > > Fix this by changing the order of acquisition in the ioctl commands that > > make use of console_lock(). > > I already have another patch [1] that fixes the same issue in a different way. > It looks less risky than yours and got more feedback. > > > Best regards, > > Florian Tobias Schandinat > > > [1] http://marc.info/?l=linux-kernel&m=130833638508657&w=2 Looks better than my version. For what it's worth it: Reviewed-by: Andrea Righi <andrea@xxxxxxxxxxxxxxx> Thanks, -Andrea -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
