linux-toradex.git/drivers/tty/vt, branch v3.1.1

Revert "tty: make receive_buf() return the amout of bytes received"

2011-06-03T21:33:24+00:00

This reverts commit b1c43f82c5aa265442f82dba31ce985ebb7aa71c.

It was broken in so many ways, and results in random odd pty issues.

It re-introduced the buggy schedule_work() in flush_to_ldisc() that can
cause endless work-loops (see commit a5660b41af6a: "tty: fix endless
work loop when the buffer fills up").

It also used an "unsigned int" return value fo the ->receive_buf()
function, but then made multiple functions return a negative error code,
and didn't actually check for the error in the caller.

And it didn't actually work at all.  BenH bisected down odd tty behavior
to it:
  "It looks like the patch is causing some major malfunctions of the X
   server for me, possibly related to PTYs.  For example, cat'ing a
   large file in a gnome terminal hangs the kernel for -minutes- in a
   loop of what looks like flush_to_ldisc/workqueue code, (some ftrace
   data in the quoted bits further down).

   ...

   Some more data: It -looks- like what happens is that the
   flush_to_ldisc work queue entry constantly re-queues itself (because
   the PTY is full ?) and the workqueue thread will basically loop
   forver calling it without ever scheduling, thus starving the consumer
   process that could have emptied the PTY."

which is pretty much exactly the problem we fixed in a5660b41af6a.

Milton Miller pointed out the 'unsigned int' issue.

Reported-by: Benjamin Herrenschmidt 
Reported-by: Milton Miller 
Cc: Stefan Bigler 
Cc: Toby Gray 
Cc: Felipe Balbi 
Cc: Greg Kroah-Hartman 
Cc: Alan Cox 
Signed-off-by: Linus Torvalds

tty: make receive_buf() return the amout of bytes received

2011-04-23T00:31:53+00:00

it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.

Tested-by: Stefan Bigler 
Tested-by: Toby Gray 
Signed-off-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

tty: Clean console safely

2011-04-19T23:33:37+00:00

Traditional \E[2J sequence erases console display but scroll-back
buffer and underlying device (frame) buffer keep data that can be
accessed by scrolling console back.

This patch introduce new \E[J parameter 3 that allows to scramble
scroll-back buffer explicitly. Session locking programs (screen,
vlock) can use it to prevent attacker to browse locked console
history.

Signed-off-by: Petr Písař 
Signed-off-by: Greg Kroah-Hartman

tty: remove invalid location line in file header

2011-04-19T23:33:36+00:00

remove invalid location line in each file header after location
moved from driver/char to driver/tty

Signed-off-by: Jovi Zhang 
Signed-off-by: Greg Kroah-Hartman

TTY: VT, remove unused variables

2011-04-19T21:41:48+00:00

drivers/tty/vt/vt.c:892:2: warning: Value stored to 'old_screen_size' is never read
        old_screen_size = vc->vc_screenbuf_size;
        ^                 ~~~~~~~~~~~~~~~~~~~~~
drivers/tty/vt/vt.c:890:2: warning: Value stored to 'old_cols' is never read
	old_cols = vc->vc_cols;
	^          ~~~~~~~~~~~

Signed-off-by: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

tty: VT, remove unused variable

2011-04-19T21:41:46+00:00

drivers/tty/vt/vt_ioctl.c:1525:2: warning: Value stored to 'kbd' is never read
kbd = kbd_table + console;
^     ~~~~~~~~~~~~~~~~~~~

Signed-off-by: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

drivers/tty/vt/vt_ioctl.c: repair insane ?: expression

2011-04-19T21:39:28+00:00

Cc: Arthur Taylor 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

vt: Add K_OFF return value to vt_ioctl KDGKBMODE

2011-04-19T21:39:28+00:00

After adding support for K_OFF in KDSKBMODE, it was forgotten to
add support for returning it in KDGKBMODE.

Signed-off-by: Arthur Taylor 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

Fix common misspellings

2011-03-31T14:26:23+00:00

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi

lib, arch: add filter argument to show_mem and fix private implementations

2011-03-25T00:49:37+00:00

Commit ddd588b5dd55 ("oom: suppress nodes that are not allowed from
meminfo on oom kill") moved lib/show_mem.o out of lib/lib.a, which
resulted in build warnings on all architectures that implement their own
versions of show_mem():

	lib/lib.a(show_mem.o): In function `show_mem':
	show_mem.c:(.text+0x1f4): multiple definition of `show_mem'
	arch/sparc/mm/built-in.o:(.text+0xd70): first defined here

The fix is to remove __show_mem() and add its argument to show_mem() in
all implementations to prevent this breakage.

Architectures that implement their own show_mem() actually don't do
anything with the argument yet, but they could be made to filter nodes
that aren't allowed in the current context in the future just like the
generic implementation.

Reported-by: Stephen Rothwell 
Reported-by: James Bottomley 
Suggested-by: Andrew Morton 
Signed-off-by: David Rientjes 
Signed-off-by: Linus Torvalds