linux-stable.git/drivers/tty/serial, branch v3.2.53 Linux kernel stable tree serial: pch_uart: fix tty-kref leak in dma-rx path 2013-10-26T20:06:05+00:00 Johan Hovold jhovold@gmail.com 2013-09-10T10:50:50+00:00 4f31ab80a2bf09ea0e57c351842da1e647cfe9da commit 19b85cfb190eb9980eaf416bff96aef4159a430e upstream. Fix tty_kref leak when tty_buffer_request room fails in dma-rx path. Note that the tty ref isn't really needed anymore, but as the leak has always been there, fixing it before removing should makes it easier to backport the fix. Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 19b85cfb190eb9980eaf416bff96aef4159a430e upstream.

Fix tty_kref leak when tty_buffer_request room fails in dma-rx path.

Note that the tty ref isn't really needed anymore, but as the leak has
always been there, fixing it before removing should makes it easier to
backport the fix.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
serial: pch_uart: fix tty-kref leak in rx-error path 2013-10-26T20:06:05+00:00 Johan Hovold jhovold@gmail.com 2013-09-10T10:50:49+00:00 73449fe73fa3d46232176fe6c73702b29b6479d2 commit fc0919c68cb2f75bb1af759315f9d7e2a9443c28 upstream. Fix tty-kref leak introduced by commit 384e301e ("pch_uart: fix a deadlock when pch_uart as console") which never put its tty reference. Signed-off-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit fc0919c68cb2f75bb1af759315f9d7e2a9443c28 upstream.

Fix tty-kref leak introduced by commit 384e301e ("pch_uart: fix a
deadlock when pch_uart as console") which never put its tty reference.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
serial/mxs-auart: increase time to wait for transmitter to become idle 2013-09-10T00:57:15+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2013-06-28T09:49:41+00:00 23d782ea98013f8d0c96233a720e9373ff741648 commit 079a036f4283e2b0e5c26080b8c5112bc0cc1831 upstream. Without this patch the driver waits ~1 ms for the UART to become idle. At 115200n8 this time is (theoretically) enough to transfer 11.5 characters (= 115200 bits/s / (10 Bits/char) * 1ms). As the mxs-auart has a fifo size of 16 characters the clock is gated too early. The problem is worse for lower baud rates. This only happens to really shut down the transmitter in the middle of a transfer if /dev/ttyAPPx isn't opened in userspace (e.g. by a getty) but was at least once (because the bootloader doesn't disable the transmitter). So increase the timeout to 20 ms which should be enough for 9600n8, too. Moreover skip gating the clock if the timeout is elapsed. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 079a036f4283e2b0e5c26080b8c5112bc0cc1831 upstream.

Without this patch the driver waits ~1 ms for the UART to become idle. At
115200n8 this time is (theoretically) enough to transfer 11.5 characters
(= 115200 bits/s / (10 Bits/char) * 1ms). As the mxs-auart has a fifo size
of 16 characters the clock is gated too early. The problem is worse for
lower baud rates.

This only happens to really shut down the transmitter in the middle of a
transfer if /dev/ttyAPPx isn't opened in userspace (e.g. by a getty) but
was at least once (because the bootloader doesn't disable the transmitter).

So increase the timeout to 20 ms which should be enough for 9600n8, too.
Moreover skip gating the clock if the timeout is elapsed.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
serial/mxs-auart: fix race condition in interrupt handler 2013-09-10T00:57:15+00:00 Uwe Kleine-König u.kleine-koenig@pengutronix.de 2013-07-04T09:28:51+00:00 5404dcaa6bc28af1bcd26e96c5010cc282c54a91 commit d970d7fe65adff5efe75b4a73c4ffc9be57089f7 upstream. The handler needs to ack the pending events before actually handling them. Otherwise a new event might come in after it it considered non-pending or handled and is acked then without being handled. So this event is only noticed when the next interrupt happens. Without this patch an i.MX28 based machine running an rt-patched kernel regularly hangs during boot. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit d970d7fe65adff5efe75b4a73c4ffc9be57089f7 upstream.

The handler needs to ack the pending events before actually handling them.
Otherwise a new event might come in after it it considered non-pending or
handled and is acked then without being handled. So this event is only
noticed when the next interrupt happens.

Without this patch an i.MX28 based machine running an rt-patched kernel
regularly hangs during boot.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
pch_uart: fix a deadlock when pch_uart as console 2013-07-27T04:34:33+00:00 Liang Li liang.li@windriver.com 2013-01-19T09:52:10+00:00 790e332c473eded2396dcf7e2902cbe4429b6a80 commit 384e301e3519599b000c1a2ecd938b533fc15d85 upstream. When we use pch_uart as system console like 'console=ttyPCH0,115200', then 'send break' to it. We'll encounter the deadlock on a cpu/core, with interrupts disabled on the core. When we happen to have all irqs affinity to cpu0 then the deadlock on cpu0 actually deadlock whole system. In pch_uart_interrupt, we have spin_lock_irqsave(&priv->lock, flags) then call pch_uart_err_ir when break is received. Then the call to dev_err would actually call to pch_console_write then we'll run into another spin_lock(&priv->lock), with interrupts disabled. So in the call sequence lead by pch_uart_interrupt, we should be carefully to call functions that will 'print message to console' only in case the uart port is not being used as serial console. Signed-off-by: Liang Li <liang.li@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 384e301e3519599b000c1a2ecd938b533fc15d85 upstream.

When we use pch_uart as system console like 'console=ttyPCH0,115200',
then 'send break' to it. We'll encounter the deadlock on a cpu/core,
with interrupts disabled on the core. When we happen to have all irqs
affinity to cpu0 then the deadlock on cpu0 actually deadlock whole
system.

In pch_uart_interrupt, we have spin_lock_irqsave(&priv->lock, flags)
then call pch_uart_err_ir when break is received. Then the call to
dev_err would actually call to pch_console_write then we'll run into
another spin_lock(&priv->lock), with interrupts disabled.

So in the call sequence lead by pch_uart_interrupt, we should be
carefully to call functions that will 'print message to console' only
in case the uart port is not being used as serial console.

Signed-off-by: Liang Li <liang.li@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Revert "serial: 8250_pci: add support for another kind of NetMos Technology PCI 9835 Multi-I/O Controller" 2013-07-27T04:34:24+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2013-06-30T16:03:06+00:00 577048c57f84b181bbaf48c3e26e401b6a6a46a9 commit 828c6a102b1f2b8583fadc0e779c46b31d448f0b upstream. This reverts commit 8d2f8cd424ca0b99001f3ff4f5db87c4e525f366. As reported by Stefan, this device already works with the parport_serial driver, so the 8250_pci driver should not also try to grab it as well. Reported-by: Stefan Seyfried <stefan.seyfried@googlemail.com> Cc: Wang YanQing <udknight@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 828c6a102b1f2b8583fadc0e779c46b31d448f0b upstream.

This reverts commit 8d2f8cd424ca0b99001f3ff4f5db87c4e525f366.

As reported by Stefan, this device already works with the parport_serial
driver, so the 8250_pci driver should not also try to grab it as well.

Reported-by: Stefan Seyfried <stefan.seyfried@googlemail.com>
Cc: Wang YanQing <udknight@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
serial_core.c: add put_device() after device_find_child() 2013-05-13T14:02:18+00:00 Federico Vaga federico.vaga@gmail.com 2013-04-15T14:01:07+00:00 392e49cb34a700ba50800075cef75e1de5f75ab8 commit 5a65dcc04cda41f4122aacc37a5a348454645399 upstream. The serial core uses device_find_child() but does not drop the reference to the retrieved child after using it. This patch add the missing put_device(). What I have done to test this issue. I used a machine with an AMBA PL011 serial driver. I tested the patch on next-20120408 because the last branch [next-20120415] does not boot on this board. For test purpose, I added some pr_info() messages to print the refcount after device_find_child() (lines: 1937,2009), and after put_device() (lines: 1947, 2021). Boot the machine *without* put_device(). Then: echo reboot > /sys/power/disk echo disk > /sys/power/state [ 87.058575] uart_suspend_port:1937 refcount 4 [ 87.058582] uart_suspend_port:1947 refcount 4 [ 87.098083] uart_resume_port:2009refcount 5 [ 87.098088] uart_resume_port:2021 refcount 5 echo disk > /sys/power/state [ 103.055574] uart_suspend_port:1937 refcount 6 [ 103.055580] uart_suspend_port:1947 refcount 6 [ 103.095322] uart_resume_port:2009 refcount 7 [ 103.095327] uart_resume_port:2021 refcount 7 echo disk > /sys/power/state [ 252.459580] uart_suspend_port:1937 refcount 8 [ 252.459586] uart_suspend_port:1947 refcount 8 [ 252.499611] uart_resume_port:2009 refcount 9 [ 252.499616] uart_resume_port:2021 refcount 9 The refcount continuously increased. Boot the machine *with* this patch. Then: echo reboot > /sys/power/disk echo disk > /sys/power/state [ 159.333559] uart_suspend_port:1937 refcount 4 [ 159.333566] uart_suspend_port:1947 refcount 3 [ 159.372751] uart_resume_port:2009 refcount 4 [ 159.372755] uart_resume_port:2021 refcount 3 echo disk > /sys/power/state [ 185.713614] uart_suspend_port:1937 refcount 4 [ 185.713621] uart_suspend_port:1947 refcount 3 [ 185.752935] uart_resume_port:2009 refcount 4 [ 185.752940] uart_resume_port:2021 refcount 3 echo disk > /sys/power/state [ 207.458584] uart_suspend_port:1937 refcount 4 [ 207.458591] uart_suspend_port:1947 refcount 3 [ 207.498598] uart_resume_port:2009 refcount 4 [ 207.498605] uart_resume_port:2021 refcount 3 The refcount correctly handled. Signed-off-by: Federico Vaga <federico.vaga@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 5a65dcc04cda41f4122aacc37a5a348454645399 upstream.

The serial core uses device_find_child() but does not drop the reference to
the retrieved child after using it. This patch add the missing put_device().

What I have done to test this issue.

I used a machine with an AMBA PL011 serial driver. I tested the patch on
next-20120408 because the last branch [next-20120415] does not boot on this
board.

For test purpose, I added some pr_info() messages to print the refcount
after device_find_child() (lines: 1937,2009), and after put_device()
(lines: 1947, 2021).

Boot the machine *without* put_device(). Then:

echo reboot > /sys/power/disk
echo disk > /sys/power/state
[   87.058575] uart_suspend_port:1937 refcount 4
[   87.058582] uart_suspend_port:1947 refcount 4
[   87.098083] uart_resume_port:2009refcount 5
[   87.098088] uart_resume_port:2021 refcount 5

echo disk > /sys/power/state
[  103.055574] uart_suspend_port:1937 refcount 6
[  103.055580] uart_suspend_port:1947 refcount 6
[  103.095322] uart_resume_port:2009 refcount 7
[  103.095327] uart_resume_port:2021 refcount 7

echo disk > /sys/power/state
[  252.459580] uart_suspend_port:1937 refcount 8
[  252.459586] uart_suspend_port:1947 refcount 8
[  252.499611] uart_resume_port:2009 refcount 9
[  252.499616] uart_resume_port:2021 refcount 9

The refcount continuously increased.

Boot the machine *with* this patch. Then:

echo reboot > /sys/power/disk
echo disk > /sys/power/state
[  159.333559] uart_suspend_port:1937 refcount 4
[  159.333566] uart_suspend_port:1947 refcount 3
[  159.372751] uart_resume_port:2009 refcount 4
[  159.372755] uart_resume_port:2021 refcount 3

echo disk > /sys/power/state
[  185.713614] uart_suspend_port:1937 refcount 4
[  185.713621] uart_suspend_port:1947 refcount 3
[  185.752935] uart_resume_port:2009 refcount 4
[  185.752940] uart_resume_port:2021 refcount 3

echo disk > /sys/power/state
[  207.458584] uart_suspend_port:1937 refcount 4
[  207.458591] uart_suspend_port:1947 refcount 3
[  207.498598] uart_resume_port:2009 refcount 4
[  207.498605] uart_resume_port:2021 refcount 3

The refcount correctly handled.

Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tty: atmel_serial_probe(): index of atmel_ports[] fix 2013-04-10T02:19:58+00:00 Pawel Wieczorkiewicz wpawel@gmail.com 2013-02-20T16:26:20+00:00 bdcde179d39c3bd0584cd51713ebea920e82742f commit 503bded92da283b2f31d87e054c4c6d30c3c2340 upstream. Index of atmel_ports[ATMEL_MAX_UART] should be smaller than ATMEL_MAX_UART. Signed-off-by: Pawel Wieczorkiewicz <wpawel@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 503bded92da283b2f31d87e054c4c6d30c3c2340 upstream.

Index of atmel_ports[ATMEL_MAX_UART] should be smaller
than ATMEL_MAX_UART.

Signed-off-by: Pawel Wieczorkiewicz <wpawel@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
sunsu: Fix panic in case of nonexistent port at "console=ttySY" cmdline option 2013-03-27T02:41:04+00:00 Tkhai Kirill tkhai@yandex.ru 2013-02-23T23:01:15+00:00 9a2b333868cfd1e9421c68fa51283ef69b0d65dc [ Upstream commit cb29529ea0030e60ef1bbbf8399a43d397a51526 ] If a machine has X (X < 4) sunsu ports and cmdline option "console=ttySY" is passed, where X < Y <= 4, than the following panic happens: Unable to handle kernel NULL pointer dereference TPC: <sunsu_console_setup+0x78/0xe0> RPC: <sunsu_console_setup+0x74/0xe0> I7: <register_console+0x378/0x3e0> Call Trace: [0000000000453a38] register_console+0x378/0x3e0 [0000000000576fa0] uart_add_one_port+0x2e0/0x340 [000000000057af40] su_probe+0x160/0x2e0 [00000000005b8a4c] platform_drv_probe+0xc/0x20 [00000000005b6c2c] driver_probe_device+0x12c/0x220 [00000000005b6da8] __driver_attach+0x88/0xa0 [00000000005b4df4] bus_for_each_dev+0x54/0xa0 [00000000005b5a54] bus_add_driver+0x154/0x260 [00000000005b7190] driver_register+0x50/0x180 [00000000006d250c] sunsu_init+0x18c/0x1e0 [00000000006c2668] do_one_initcall+0xe8/0x160 [00000000006c282c] kernel_init_freeable+0x12c/0x1e0 [0000000000603764] kernel_init+0x4/0x100 [0000000000405f64] ret_from_syscall+0x1c/0x2c [0000000000000000] (null) 1)Fix the panic; 2)Increment registered port number every successful probe. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> CC: David Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
[ Upstream commit cb29529ea0030e60ef1bbbf8399a43d397a51526 ]

If a machine has X (X < 4) sunsu ports and cmdline
option "console=ttySY" is passed, where X < Y <= 4,
than the following panic happens:

Unable to handle kernel NULL pointer dereference
TPC: <sunsu_console_setup+0x78/0xe0>
RPC: <sunsu_console_setup+0x74/0xe0>
I7: <register_console+0x378/0x3e0>
Call Trace:
 [0000000000453a38] register_console+0x378/0x3e0
 [0000000000576fa0] uart_add_one_port+0x2e0/0x340
 [000000000057af40] su_probe+0x160/0x2e0
 [00000000005b8a4c] platform_drv_probe+0xc/0x20
 [00000000005b6c2c] driver_probe_device+0x12c/0x220
 [00000000005b6da8] __driver_attach+0x88/0xa0
 [00000000005b4df4] bus_for_each_dev+0x54/0xa0
 [00000000005b5a54] bus_add_driver+0x154/0x260
 [00000000005b7190] driver_register+0x50/0x180
 [00000000006d250c] sunsu_init+0x18c/0x1e0
 [00000000006c2668] do_one_initcall+0xe8/0x160
 [00000000006c282c] kernel_init_freeable+0x12c/0x1e0
 [0000000000603764] kernel_init+0x4/0x100
 [0000000000405f64] ret_from_syscall+0x1c/0x2c
 [0000000000000000]           (null)

1)Fix the panic;
2)Increment registered port number every successful
probe.

Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
CC: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tty: serial: fix typo "ARCH_S5P6450" 2013-03-20T15:03:34+00:00 Paul Bolle pebolle@tiscali.nl 2013-03-09T22:16:44+00:00 88ef123457c203b3c2a40ecb9b3022ecdd7b7dcb commit 827aa0d36d486f359808c8fb931cf7a71011a09d upstream. This could have been either ARCH_S5P64X0 or CPU_S5P6450. Looking at commit 2555e663b367b8d555e76023f4de3f6338c28d6c ("ARM: S5P64X0: Add UART serial support for S5P6450") - which added this typo - makes clear this should be CPU_S5P6450. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 827aa0d36d486f359808c8fb931cf7a71011a09d upstream.

This could have been either ARCH_S5P64X0 or CPU_S5P6450. Looking at
commit 2555e663b367b8d555e76023f4de3f6338c28d6c ("ARM: S5P64X0: Add UART
serial support for S5P6450") - which added this typo - makes clear this
should be CPU_S5P6450.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>