On Thu, Jul 10, 2014 at 04:12:05PM -0700, David Miller wrote: > From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > Date: Thu, 10 Jul 2014 16:14:32 -0700 > > > On Sun, Jul 06, 2014 at 11:29:51AM -0400, Peter Hurley wrote: > >> Cc: Seth Bollinger <sethb@xxxxxxxx> > >> Cc: Aaro Koskinen <aaro.koskinen@xxxxxx> > >> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx> > >> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> > >> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> > >> > >> Greg, > >> > >> I completed the audit of serial drivers after reports that > >> several Sun serial drivers were broken by > >> commit 717f3bbab3c7628736ef738fdbf3d9a28578c26c, > >> 'serial_core: Fix conditional start_tx on ring buffer not empty'. > >> > >> I apologize for not submitting this sooner. The delay was due to > >> an ongoing analysis of serial flow control prompted by Sam Ravnborg's > >> question: > >> > >> On 06/10/2014 03:24 PM, Sam Ravnborg wrote: > >> > I also noticed the typical pattern is: > >> > > >> > if (uart_circ_empty(xmit) || uart_tx_stopped(port)) > >> > > >> > Should you use this pattern also in sunsab.c? > >> > >> Unfortunately, that analysis revealed that tx flow control is > >> largely SMP-unsafe, and it's fairly easy to corrupt the hardware > >> state wrt. the tty flow control state. > >> > >> I'm still working on the solutions to that; they're too > >> extensive to submit for 3.16 anyway. > > > > So these should go into 3.16-final? Or 3.17? > > Definitely 3.16, this regression is several releases old. Ok, will queue it up, thanks. gre gk-h -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
