| From c7084edc3f6d67750f50d4183134c4fb5712a5c8 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Date: Fri, 5 Apr 2019 15:39:26 +0200 |
| Subject: tty: mark Siemens R3964 line discipline as BROKEN |
| |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| commit c7084edc3f6d67750f50d4183134c4fb5712a5c8 upstream. |
| |
| The n_r3964 line discipline driver was written in a different time, when |
| SMP machines were rare, and users were trusted to do the right thing. |
| Since then, the world has moved on but not this code, it has stayed |
| rooted in the past with its lovely hand-crafted list structures and |
| loads of "interesting" race conditions all over the place. |
| |
| After attempting to clean up most of the issues, I just gave up and am |
| now marking the driver as BROKEN so that hopefully someone who has this |
| hardware will show up out of the woodwork (I know you are out there!) |
| and will help with debugging a raft of changes that I had laying around |
| for the code, but was too afraid to commit as odds are they would break |
| things. |
| |
| Many thanks to Jann and Linus for pointing out the initial problems in |
| this codebase, as well as many reviews of my attempts to fix the issues. |
| It was a case of whack-a-mole, and as you can see, the mole won. |
| |
| Reported-by: Jann Horn <jannh@google.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| |
| --- |
| drivers/char/Kconfig | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/char/Kconfig |
| +++ b/drivers/char/Kconfig |
| @@ -351,7 +351,7 @@ config XILINX_HWICAP |
| |
| config R3964 |
| tristate "Siemens R3964 line discipline" |
| - depends on TTY |
| + depends on TTY && BROKEN |
| ---help--- |
| This driver allows synchronous communication with devices using the |
| Siemens R3964 packet protocol. Unless you are dealing with special |