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2014-07-17serial: imx: Fix build breakagePeter Hurley
commit 8bec751bd63847b4044aab8b215db52aa6abde61 upstream. Fix breakage introduced by commit c557d392fbf5badd693ea1946a4317c87a26a716, 'serial: Test for no tx data on tx restart'. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17serial: Test for no tx data on tx restartPeter Hurley
commit c557d392fbf5badd693ea1946a4317c87a26a716 upstream. Commit 717f3bbab3c7628736ef738fdbf3d9a28578c26c, 'serial_core: Fix conditional start_tx on ring buffer not empty' exposes an incorrect assumption in several drivers' start_tx methods; the tx ring buffer can, in fact, be empty when restarting tx while performing flow control. Affected drivers: sunsab.c ip22zilog.c pmac_zilog.c sunzilog.c m32r_sio.c imx.c Other in-tree serial drivers either are not affected or already test for empty tx ring buffer before transmitting. Test for empty tx ring buffer in start_tx() method, after transmitting x_char (if applicable). Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: Seth Bollinger <sethb@digi.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09tty: Correct INPCK handlingPeter Hurley
commit 66528f90669691c85c73bea4f0c9f4a5857c4cab upstream. If INPCK is not set, input parity detection should be disabled. This means parity errors should not be received from the tty driver, and the data received should be treated normally. SUS v3, 11.2.2, General Terminal Interface - Input Modes, states: "If INPCK is set, input parity checking shall be enabled. If INPCK is not set, input parity checking shall be disabled, allowing output parity generation without input parity errors. Note that whether input parity checking is enabled or disabled is independent of whether parity detection is enabled or disabled (see Control Modes). If parity detection is enabled but input parity checking is disabled, the hardware to which the terminal is connected shall recognize the parity bit, but the terminal special file shall not check whether or not this bit is correctly set." Ignore parity errors reported by the tty driver when INPCK is not set, and handle the received data normally. Fixes: Bugzilla #71681, 'Improvement of n_tty_receive_parity_error from n_tty.c' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-09serial: Fix IGNBRK handlingPeter Hurley
commit ef8b9ddcb45fa3b1e11acd72be2398001e807d14 upstream. If IGNBRK is set without either BRKINT or PARMRK set, some uart drivers send a 0x00 byte for BREAK without the TTYBREAK flag to the line discipline, when it should send either nothing or the TTYBREAK flag set. This happens because the read_status_mask masks out the BI condition, which uart_insert_char() then interprets as a normal 0x00 byte. SUS v3 is clear regarding the meaning of IGNBRK; Section 11.2.2, General Terminal Interface - Input Modes, states: "If IGNBRK is set, a break condition detected on input shall be ignored; that is, not put on the input queue and therefore not read by any process." Fix read_status_mask to include the BI bit if IGNBRK is set; the lsr status retains the BI bit if a BREAK is recv'd, which is subsequently ignored in uart_insert_char() when masked with the ignore_status_mask. Affected drivers: 8250 - all serial_txx9 mfd amba-pl010 amba-pl011 atmel_serial bfin_uart dz ip22zilog max310x mxs-auart netx-serial pnx8xxx_uart pxa sb1250-duart sccnxp serial_ks8695 sirfsoc_uart st-asc vr41xx_siu zs sunzilog fsl_lpuart sunsab ucc_uart bcm63xx_uart sunsu efm32-uart pmac_zilog mpsc msm_serial m32r_sio Unaffected drivers: omap-serial rp2 sa1100 imx icom Annotated for fixes: altera_uart mcf Drivers without break detection: 21285 xilinx-uartps altera_jtaguart apbuart arc-uart clps711x max3100 uartlite msm_serial_hs nwpserial lantiq vt8500_serial Unknown: samsung mpc52xx_uart bfin_sport_uart cpm_uart/core Fixes: Bugzilla #71651, '8250_core.c incorrectly handles IGNBRK flag' Reported-by: Ivan <athlon_@mail.ru> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-30printk/of_serial: fix serial console cessation part way through boot.Stephen Chivers
commit 7fa21dd8bd191564a195291161d6b43db5d9c350 upstream. Commit 5f5c9ae56c38942623f69c3e6dc6ec78e4da2076 "serial_core: Unregister console in uart_remove_one_port()" fixed a crash where a serial port was removed but not deregistered as a console. There is a side effect of that commit for platforms having serial consoles and of_serial configured (CONFIG_SERIAL_OF_PLATFORM). The serial console is disabled midway through the boot process. This cessation of the serial console affects PowerPC computers such as the MVME5100 and SAM440EP. The sequence is: bootconsole [udbg0] enabled .... serial8250/16550 driver initialises and registers its UARTS, one of these is the serial console. console [ttyS0] enabled .... of_serial probes "platform" devices, registering them as it goes. One of these is the serial console. console [ttyS0] disabled. The disabling of the serial console is due to: a. unregister_console in printk not clearing the CONS_ENABLED bit in the console flags, even though it has announced that the console is disabled; and b. of_platform_serial_probe in of_serial not setting the port type before it registers with serial8250_register_8250_port. This patch ensures that the serial console is re-enabled when of_serial registers a serial port that corresponds to the designated console. === The above failure was identified in Linux-3.15-rc2. Tested using MVME5100 and SAM440EP PowerPC computers with kernels built from Linux-3.15-rc5 and tty-next. The continued operation of the serial console is vital for computers such as the MVME5100 as that Single Board Computer does not have any grapical/display hardware. Signed-off-by: Stephen Chivers <schivers@csc.com> Tested-by: Stephen Chivers <schivers@csc.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [unregister_console] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-24Staging: speakup: Update __speakup_paste_selection() tty (ab)usage to match vtBen Hutchings
This function is largely a duplicate of paste_selection() in drivers/tty/vt/selection.c, but with its own selection state. The speakup selection mechanism should really be merged with vt. For now, apply the changes from 'TTY: vt, fix paste_selection ldisc handling', 'tty: Make ldisc input flow control concurrency-friendly', and 'tty: Fix unsafe vt paste_selection()'. References: https://bugs.debian.org/735202 References: https://bugs.debian.org/744015 Reported-by: Paul Gevers <elbrus@debian.org> Reported-and-tested-by: Jarek Czekalski <jarekczek@poczta.onet.pl> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: <stable@vger.kernel.org> # v3.8 but needs backporting for < 3.12 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03tty: Fix lockless tty buffer racePeter Hurley
Commit 6a20dbd6caa2358716136144bf524331d70b1e03, "tty: Fix race condition between __tty_buffer_request_room and flush_to_ldisc" correctly identifies an unsafe race condition between __tty_buffer_request_room() and flush_to_ldisc(), where the consumer flush_to_ldisc() prematurely advances the head before consuming the last of the data committed. For example: CPU 0 | CPU 1 __tty_buffer_request_room | flush_to_ldisc ... | ... | count = head->commit - head->read n = tty_buffer_alloc() | b->commit = b->used | b->next = n | | if (!count) /* T */ | if (head->next == NULL) /* F */ | buf->head = head->next In this case, buf->head has been advanced but head->commit may have been updated with a new value. Instead of reintroducing an unnecessary lock, fix the race locklessly. Read the commit-next pair in the reverse order of writing, which guarantees the commit value read is the latest value written if the head is advancing. Reported-by: Manfred Schlaegl <manfred.schlaegl@gmx.at> Cc: <stable@vger.kernel.org> # 3.12.x+ Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03Revert "tty: Fix race condition between __tty_buffer_request_room and ↵Peter Hurley
flush_to_ldisc" This reverts commit 6a20dbd6caa2358716136144bf524331d70b1e03. Although the commit correctly identifies an unsafe race condition between __tty_buffer_request_room() and flush_to_ldisc(), the commit fixes the race with an unnecessary spinlock in a lockless algorithm. The follow-on commit, "tty: Fix lockless tty buffer race" fixes the race locklessly. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03drivers/tty/hvc: don't free hvc_console_setup after initTomoki Sekiyama
When 'console=hvc0' is specified to the kernel parameter in x86 KVM guest, hvc console is setup within a kthread. However, that will cause SEGV and the boot will fail when the driver is builtin to the kernel, because currently hvc_console_setup() is annotated with '__init'. This patch removes '__init' to boot the guest successfully with 'console=hvc0'. Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03n_tty: Fix n_tty_write crash when echoing in raw modePeter Hurley
The tty atomic_write_lock does not provide an exclusion guarantee for the tty driver if the termios settings are LECHO & !OPOST. And since it is unexpected and not allowed to call TTY buffer helpers like tty_insert_flip_string concurrently, this may lead to crashes when concurrect writers call pty_write. In that case the following two writers: * the ECHOing from a workqueue and * pty_write from the process race and can overflow the corresponding TTY buffer like follows. If we look into tty_insert_flip_string_fixed_flag, there is: int space = __tty_buffer_request_room(port, goal, flags); struct tty_buffer *tb = port->buf.tail; ... memcpy(char_buf_ptr(tb, tb->used), chars, space); ... tb->used += space; so the race of the two can result in something like this: A B __tty_buffer_request_room __tty_buffer_request_room memcpy(buf(tb->used), ...) tb->used += space; memcpy(buf(tb->used), ...) ->BOOM B's memcpy is past the tty_buffer due to the previous A's tb->used increment. Since the N_TTY line discipline input processing can output concurrently with a tty write, obtain the N_TTY ldisc output_lock to serialize echo output with normal tty writes. This ensures the tty buffer helper tty_insert_flip_string is not called concurrently and everything is fine. Note that this is nicely reproducible by an ordinary user using forkpty and some setup around that (raw termios + ECHO). And it is present in kernels at least after commit d945cb9cce20ac7143c2de8d88b187f62db99bdc (pty: Rework the pty layer to use the normal buffering logic) in 2.6.31-rc3. js: add more info to the commit log js: switch to bool js: lock unconditionally js: lock only the tty->ops->write call References: CVE-2014-0196 Reported-and-tested-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-03tty: serial: 8250_core.c Bug fix for Exar chips.Michael Welling
The sleep function was updated to put the serial port to sleep only when necessary. This appears to resolve the errant behavior of the driver as described in Kernel Bug 61961 – "My Exar Corp. XR17C/D152 Dual PCI UART modem does not work with 3.8.0". Signed-off-by: Michael Welling <mwelling@ieee.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24serial_core: fix uart PORT_UNKNOWN handlingThomas Pfaff
While porting a RS485 driver from 2.6.29 to 3.14, i noticed that the serial tty driver could break it by using uart ports that it does not own : 1. uart_change_pm ist called during uart_open and calls the uart pm function without checking for PORT_UNKNOWN. The fix is to move uart_change_pm from uart_open to uart_port_startup. 2. The return code from the uart request_port call in uart_set_info is not handled properly, leading to the situation that the serial driver also thinks it owns the uart ports. This can triggered by doing following actions : setserial /dev/ttyS0 uart none # release the uart ports modprobe lirc-serial # or any other device that uses the uart setserial /dev/ttyS0 uart 16550 # gives no error and the uart tty driver # can use the ports as well Signed-off-by: Thomas Pfaff <tpfaff@pcs.com> Reviewed-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24serial: samsung: Change barrier() to cpu_relax() in console outputDoug Anderson
The two functions to write out to the console (one used in normal console mode and one in polling console mode) were slightly different. One used a barrier() in its loop and the other a cpu_relax(). The barrier() really doesn't do anything since we're using rd_regl() to read the port anyway. Switch it to cpu_relax() to make things consistent. No known bugs / issues are fixed by this change--it just makes things more consistent. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24serial: samsung: don't check config for every characterDoug Anderson
The s3c24xx_serial_console_putchar() is _only_ ever used by s3c24xx_serial_console_write() and is called in a loop (indirectly through uart_console_write()). There's no reason to call s3c24xx_port_configured() for every iteration through the loop. Move it outside the loop. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24serial: samsung: Use the passed in "port", fixing kgdb w/ no consoleDoug Anderson
The two functions in the samsung serial driver used for writing characters out to the port were inconsistent about whether they used the passed in "port" or the global "cons_uart". There was no reason to use the global and the use of the global in s3c24xx_serial_put_poll_char() caused a crash in the case where you used the serial port for kgdboc but not for console. Fix it so we used the passed in variable. Note that this doesn't fix all problems with the samsung serial driver. Specifically: * s3c24xx_serial_console_putchar() is still 99% identical to s3c24xx_serial_put_poll_char() (the function signature is different, but that's about it). A future patch will make them slightly less identical and judging by other serial drivers we may need yet more differences eventually. * The samsung serial driver still doesn't allow you to have more than one console port since it still uses the global cons_uart in s3c24xx_serial_console_write(). Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24serial: 8250: Fix thread unsafe __dma_tx_complete functionLoic Poulain
__dma_tx_complete is not protected against concurrent call of serial8250_tx_dma. it can lead to circular tail index corruption or parallel call of serial_tx_dma on the same data portion. This patch fixes this issue by holding the port lock. Signed-off-by: Loic Poulain <loic.poulain@intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-248250_core: Fix unwanted TX chars writeLoic Poulain
On transmit-hold-register empty, serial8250_tx_chars should be called only if we don't use DMA. DMA has its own tx cycle. Signed-off-by: Loic Poulain <loic.poulain@intel.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-24tty: Fix race condition between __tty_buffer_request_room and flush_to_ldiscManfred Schlaegl
The race was introduced while development of linux-3.11 by e8437d7ecbc50198705331449367d401ebb3181f and e9975fdec0138f1b2a85b9624e41660abd9865d4. Originally it was found and reproduced on linux-3.12.15 and linux-3.12.15-rt25, by sending 500 byte blocks with 115kbaud to the target uart in a loop with 100 milliseconds delay. In short: 1. The consumer flush_to_ldisc is on to remove the head tty_buffer. 2. The producer adds a number of bytes, so that a new tty_buffer must be allocated and added by __tty_buffer_request_room. 3. The consumer removes the head tty_buffer element, without handling newly committed data. Detailed example: * Initial buffer: * Head, Tail -> 0: used=250; commit=250; read=240; next=NULL * Consumer: ''flush_to_ldisc'' * consumed 10 Byte * buffer: * Head, Tail -> 0: used=250; commit=250; read=250; next=NULL {{{ count = head->commit - head->read; // count = 0 if (!count) { // enter // INTERRUPTED BY PRODUCER -> if (head->next == NULL) break; buf->head = head->next; tty_buffer_free(port, head); continue; } }}} * Producer: tty_insert_flip_... 10 bytes + tty_flip_buffer_push * buffer: * Head, Tail -> 0: used=250; commit=250; read=250; next=NULL * added 6 bytes: head-element filled to maximum. * buffer: * Head, Tail -> 0: used=256; commit=250; read=250; next=NULL * added 4 bytes: __tty_buffer_request_room is called * buffer: * Head -> 0: used=256; commit=256; read=250; next=1 * Tail -> 1: used=4; commit=0; read=250 next=NULL * push (tty_flip_buffer_push) * buffer: * Head -> 0: used=256; commit=256; read=250; next=1 * Tail -> 1: used=4; commit=4; read=250 next=NULL * Consumer {{{ count = head->commit - head->read; if (!count) { // INTERRUPTED BY PRODUCER <- if (head->next == NULL) // -> no break break; buf->head = head->next; tty_buffer_free(port, head); // ERROR: tty_buffer head freed -> 6 bytes lost continue; } }}} This patch reintroduces a spin_lock to protect this case. Perhaps later a lock-less solution could be found. Signed-off-by: Manfred Schlaegl <manfred.schlaegl@gmx.at> Cc: stable <stable@vger.kernel.org> # 3.11 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-17Revert "serial: 8250, disable "too much work" messages"Greg Kroah-Hartman
This reverts commit f4f653e9875e573860e783fecbebde284a8626f5. Jiri writes: No, please drop this one. We need a better solution as it turned out that some boxes need 16k loops and it will increase with new processors :(. Cc: Jiri Slaby <jslaby@suse.cz> Cc: Martin Pluskal <mpluskal@suse.com> Cc: Takashi Iwai <tiwai@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: amba-pl011: fix regression, causing an Oops on rmmodGuennadi Liakhovetski
A recent commit ef2889f7ffee67f0aed49e854c72be63f1466759 "serial: pl011: Move uart_register_driver call to device probe" introduced a regression, causing the pl011 driver to Oops if more than 1 port have been probed. Fix the Oops by only calling uart_unregister_driver() once after the last port has been removed. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16tty: fix memleak in alloc_pidChen Tingjie
There is memleak in alloc_pid: ------------------------------ unreferenced object 0xd3453a80 (size 64): comm "adbd", pid 1730, jiffies 66363 (age 6586.950s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 40 c2 f6 d5 00 d3 25 c1 59 28 00 00 ....@.....%.Y(.. backtrace: [<c1a6f15c>] kmemleak_alloc+0x3c/0xa0 [<c1320546>] kmem_cache_alloc+0xc6/0x190 [<c125d51e>] alloc_pid+0x1e/0x400 [<c123d344>] copy_process.part.39+0xad4/0x1120 [<c123da59>] do_fork+0x99/0x330 [<c123dd58>] sys_fork+0x28/0x30 [<c1a89a08>] syscall_call+0x7/0xb [<ffffffff>] 0xffffffff the leak is due to unreleased pid->count, which execute in function: get_pid()(pid->count++) and put_pid()(pid->count--). The race condition as following: task[dumpsys] task[adbd] in disassociate_ctty() in tty_signal_session_leader() ----------------------- ------------------------- tty = get_current_tty(); // tty is not NULL ... spin_lock_irq(&current->sighand->siglock); put_pid(current->signal->tty_old_pgrp); current->signal->tty_old_pgrp = NULL; spin_unlock_irq(&current->sighand->siglock); spin_lock_irq(&p->sighand->siglock); ... p->signal->tty = NULL; ... spin_unlock_irq(&p->sighand->siglock); tty = get_current_tty(); // tty NULL, goto else branch by accident. if (tty) { ... put_pid(tty_session); put_pid(tty_pgrp); ... } else { print msg } in task[dumpsys], in disassociate_ctty(), tty is set NULL by task[adbd], tty_signal_session_leader(), then it goto else branch and lack of put_pid(), cause memleak. move spin_unlock(sighand->siglock) after get_current_tty() can avoid the race and fix the memleak. Signed-off-by: Zhang Jun <jun.zhang@intel.com> Signed-off-by: Chen Tingjie <tingjie.chen@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: 8250, disable "too much work" messagesJiri Slaby
The 8250 driver now reports many of these: serial8250: too much work for irq4 These messages turned out to be common these days with a use of virtualization. I tried to increase the limit of processed characters in commit e7328ae1848966181a7ac47e8ae6cddbd2cf55f3 (serial: 8250, increase PASS_LIMIT) in 2011. It was raised from 256 to 512, but it is still not enough, apparently. So disable the warning unless somebody turns on DEBUG (or DYNAMIC_DEBUG _and_ the message). Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: Martin Pluskal <mpluskal@suse.com> Reported-by: Takashi Iwai <tiwai@suse.com> Tested-by: Takashi Iwai <tiwai@suse.de> References: https://bugzilla.novell.com/show_bug.cgi?id=868394 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: omap: Fix missing pm_runtime_resume handling by simplifying codeTony Lindgren
The lack of pm_runtime_resume handling for the device state leads into device wake-up interrupts not working after a while for runtime PM. Also, serial-omap is confused about the use of device_may_wakeup. The checks for device_may_wakeup should only be done for suspend and resume, not for pm_runtime_suspend and pm_runtime_resume. The wake-up events for PM runtime should always be enabled. The lack of pm_runtime_resume handling leads into device wake-up interrupts not working after a while for runtime PM. Rather than try to patch over the issue of adding complex tests to the pm_runtime_resume, let's fix the issues properly: 1. Make serial_omap_enable_wakeup deal with all internal PM state handling so we don't need to test for up->wakeups_enabled elsewhere. Later on once omap3 boots in device tree only mode we can also remove the up->wakeups_enabled flag and rely on the wake-up interrupt enable/disable state alone. 2. Do the device_may_wakeup checks in suspend and resume only, for runtime PM the wake-up events need to be always enabled. 3. Finally just call serial_omap_enable_wakeup and make sure we call it also in pm_runtime_resume. 4. Note that we also have to use disable_irq_nosync as serial_omap_irq calls pm_runtime_get_sync. Fixes: 2a0b965cfb6e (serial: omap: Add support for optional wake-up) Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Tony Lindgren <tony@atomide.com> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial_core: Fix pm imbalance on unbindGeert Uytterhoeven
When a serial port is closed, uart_close() takes care of shutting down the hardware, and powering it down. When a serial port is unbound while in use, uart_close() bypasses all of this, as this is supposed to be done through uart_hangup() (invoked via tty_vhangup() in uart_remove_one_port()). However, uart_hangup() does not set the hardware's power state, leaving it powered up. This may also lead to unbounded nesting counts in clock and power management, depending on their internal implementation. Make sure to power down the port in uart_hangup(), except when the port is used as a serial console. For serial consoles, this operation must be postponed until after the port becomes completely unused. This case is not fixed yet, as it depends on a (future) fix for the tty->count vs. port->count imbalance on failed uart_open(). After this, the module clock used by the sh-sci driver is disabled on unbind while the serial port is in use. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: pl011: change Rx burst size to half of trigger levelGuennadi Liakhovetski
The amba-pl011.c driver sets DMA burst size equal to FIFO trigger level. If now exactly DMA burst size bytes are received, the DMAC will retrieve them all and no Rx timeout interrupt will be generated. To fix that set the burst size to half the FIFO trigger level. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: timberdale: Depend on X86_32Jean Delvare
As far as I know the Timberdale chip was only used as a companion for Intel Atom E600 series processors. As such, its drivers are only useful on X86_32. Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: st-asc: Fix SysRq char handlingDaniel Thompson
This driver, like several others, uses the upper bits of the character to track both real and dummy state. Unfortunately it neglects to mask these bits properly when passing the character data around. This means neither break detection nor sysrq character handling work correctly. This patch adds the requires masking and has been tested to confirm that it correctly handles magic sysrq sequences on ST's B2020 board. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16Revert "serial: clps711x: Give a chance to perform useful tasks during wait ↵Alexander Shiyan
loop" This reverts commit 63e3ad3252695a2b8c01b6f6c225e4537af08b85, since this not works as expected and produce runtime error: BUG: sleeping function called from invalid context at drivers/tty/serial/clps711x.c:379 in_atomic(): 0, irqs_disabled(): 128, pid: 287, name: mount Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial_core: Fix conditional start_tx on ring buffer not emptySeth Bollinger
If the serial_core ring buffer empties just as the tty layer receives an XOFF, then start_tx will never be called when the tty layer receives an XON as the serial_core ring buffer is empty. This will possibly leave a few bytes trapped in the fifo for drivers that disable the transmitter when flow controlled. Signed-off-by: Seth Bollinger <sethb@digi.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: efm32: use $vendor,$device scheme for compatible stringUwe Kleine-König
Wolfram Sang pointed out that "efm32,$device" is non-standard. So use the common scheme and prefix device with "efm32-". The old compatible string is left in place until arch/arm/boot/dts/efm32* is fixed. Reported-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-16serial: omap: free the wakeup settings in removeSanjay Singh Rawat
Signed-off-by: Sanjay Singh Rawat <sanjay.rawat@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-12Merge git://git.infradead.org/users/eparis/auditLinus Torvalds
Pull audit updates from Eric Paris. * git://git.infradead.org/users/eparis/audit: (28 commits) AUDIT: make audit_is_compat depend on CONFIG_AUDIT_COMPAT_GENERIC audit: renumber AUDIT_FEATURE_CHANGE into the 1300 range audit: do not cast audit_rule_data pointers pointlesly AUDIT: Allow login in non-init namespaces audit: define audit_is_compat in kernel internal header kernel: Use RCU_INIT_POINTER(x, NULL) in audit.c sched: declare pid_alive as inline audit: use uapi/linux/audit.h for AUDIT_ARCH declarations syscall_get_arch: remove useless function arguments audit: remove stray newline from audit_log_execve_info() audit_panic() call audit: remove stray newlines from audit_log_lost messages audit: include subject in login records audit: remove superfluous new- prefix in AUDIT_LOGIN messages audit: allow user processes to log from another PID namespace audit: anchor all pid references in the initial pid namespace audit: convert PPIDs to the inital PID namespace. pid: get pid_t ppid of task in init_pid_ns audit: rename the misleading audit_get_context() to audit_take_context() audit: Add generic compat syscall support audit: Add CONFIG_HAVE_ARCH_AUDITSYSCALL ...
2014-04-07tty/hvc_opal: Kick the HVC thread on OPAL console eventsBenjamin Herrenschmidt
The firmware can notify us when new input data is available, so let's make sure we wakeup the HVC thread in that case. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-04-05Merge tag 'drivers-3.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC driver changes from Arnd Bergmann: "These changes are mostly for ARM specific device drivers that either don't have an upstream maintainer, or that had the maintainer ask us to pick up the changes to avoid conflicts. A large chunk of this are clock drivers (bcm281xx, exynos, versatile, shmobile), aside from that, reset controllers for STi as well as a large rework of the Marvell Orion/EBU watchdog driver are notable" * tag 'drivers-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (99 commits) Revert "dts: socfpga: Add DTS entry for adding the stmmac glue layer for stmmac." Revert "net: stmmac: Add SOCFPGA glue driver" ARM: shmobile: r8a7791: Fix SCIFA3-5 clocks ARM: STi: Add reset controller support to mach-sti Kconfig drivers: reset: stih416: add softreset controller drivers: reset: stih415: add softreset controller drivers: reset: Reset controller driver for STiH416 drivers: reset: Reset controller driver for STiH415 drivers: reset: STi SoC system configuration reset controller support dts: socfpga: Add sysmgr node so the gmac can use to reference dts: socfpga: Add support for SD/MMC on the SOCFPGA platform reset: Add optional resets and stubs ARM: shmobile: r7s72100: fix bus clock calculation Power: Reset: Generalize qnap-poweroff to work on Synology devices. dts: socfpga: Update clock entry to support multiple parents ARM: socfpga: Update socfpga_defconfig dts: socfpga: Add DTS entry for adding the stmmac glue layer for stmmac. net: stmmac: Add SOCFPGA glue driver watchdog: orion_wdt: Use %pa to print 'phys_addr_t' drivers: cci: Export CCI PMU revision ...
2014-04-05Merge tag 'cleanup-3.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC cleanups from Arnd Bergmann: "These cleanup patches are mainly move stuff around and should all be harmless. They are mainly split out so that other branches can be based on top to avoid conflicts. Notable changes are: - We finally remove all mach/timex.h, after CLOCK_TICK_RATE is no longer used (Uwe Kleine-König) - The Qualcomm MSM platform is split out into legacy mach-msm and new-style mach-qcom, to allow easier maintainance of the new hardware support without regressions (Kumar Gala) - A rework of some of the Kconfig logic to simplify multiplatform support (Rob Herring) - Samsung Exynos gets closer to supporting multiplatform (Sachin Kamat and others) - mach-bcm3528 gets merged into mach-bcm (Stephen Warren) - at91 gains some common clock framework support (Alexandre Belloni, Jean-Jacques Hiblot and other French people)" * tag 'cleanup-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (89 commits) ARM: hisi: select HAVE_ARM_SCU only for SMP ARM: efm32: allow uncompress debug output ARM: prima2: build reset code standalone ARM: at91: add PWM clock ARM: at91: move sam9261 SoC to common clk ARM: at91: prepare common clk transition for sam9261 SoC ARM: at91: updated the at91_dt_defconfig with support for the ADS7846 ARM: at91: dt: sam9261: Device Tree support for the at91sam9261ek ARM: at91: dt: defconfig: Added the sam9261 to the list of DT-enabled SOCs ARM: at91: dt: Add at91sam9261 dt SoC support ARM: at91: switch sam9rl to common clock framework ARM: at91/dt: define main clk frequency of at91sam9rlek ARM: at91/dt: define at91sam9rl clocks ARM: at91: prepare common clk transition for sam9rl SoCs ARM: at91: prepare sam9 dt boards transition to common clk ARM: at91: dt: sam9rl: Device Tree for the at91sam9rlek ARM: at91/defconfig: Add the sam9rl to the list of DT-enabled SOCs ARM: at91: Add at91sam9rl DT SoC support ARM: at91: prepare at91sam9rl DT transition ARM: at91/defconfig: refresh at91sam9260_9g20_defconfig ...
2014-04-01Merge tag 'tty-3.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver update from Greg KH: "Here's the big tty/serial driver update for 3.15-rc1. Nothing major, a number of serial driver updates and a few tty core fixes as well. All have been in linux-next for a while" * tag 'tty-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (71 commits) tty/serial: omap: empty the RX FIFO at the end of half-duplex TX tty/serial: omap: fix RX interrupt enable/disable in half-duplex TX serial: sh-sci: Neaten dev_<level> uses serial: sh-sci: Replace hardcoded 3 by UART_PM_STATE_OFF serial: sh-sci: Add more register documentation serial: sh-sci: Remove useless casts serial: sh-sci: Replace printk() by pr_*() serial_core: Avoid NULL pointer dereference in uart_close() serial_core: Get a reference for port->tty in uart_remove_one_port() serial: clps711x: Give a chance to perform useful tasks during wait loop serial_core: Grammar s/ports/port's/ serial_core: Spelling s/contro/control/ serial: efm32: properly namespace location property serial: max310x: Add missing #include <linux/uaccess.h> synclink: fix info leak in ioctl serial: 8250: Clean up the locking for -rt serial: 8250_pci: change BayTrail default uartclk serial: 8250_pci: more BayTrail error-free bauds serial: sh-sci: Add missing call to uart_remove_one_port() in failure path serial_core: Unregister console in uart_remove_one_port() ...
2014-04-01Merge tag 'pm+acpi-3.15-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "The majority of this material spent some time in linux-next, some of it even several weeks. There are a few relatively fresh commits in it, but they are mostly fixes and simple cleanups. ACPI took the lead this time, both in terms of the number of commits and the number of modified lines of code, cpufreq follows and there are a few changes in the PM core and in cpuidle too. A new feature that already got some LWN.net's attention is the device PM QoS extension allowing latency tolerance requirements to be propagated from leaf devices to their ancestors with hardware interfaces for specifying latency tolerance. That should help systems with hardware-driven power management to avoid going too far with it in cases when there are latency tolerance constraints. There also are some significant changes in the ACPI core related to the way in which hotplug notifications are handled. They affect PCI hotplug (ACPIPHP) and the ACPI dock station code too. The bottom line is that all those notification now go through the root notify handler and are propagated to the interested subsystems by means of callbacks instead of having to install a notify handler for each device object that we can potentially get hotplug notifications for. In addition to that ACPICA will now advertise "Windows 2013" compatibility for _OSI, because some systems out there don't work correctly if that is not done (some of them don't even boot). On the system suspend side of things, all of the device suspend and resume callbacks, except for ->prepare() and ->complete(), are now going to be executed asynchronously as that turns out to speed up system suspend and resume on some platforms quite significantly and we have a few more optimizations in that area. Apart from that, there are some new device IDs and fixes and cleanups all over. In particular, the system suspend and resume handling by cpufreq should be improved and the cpuidle menu governor should be a bit more robust now. Specifics: - Device PM QoS support for latency tolerance constraints on systems with hardware interfaces allowing such constraints to be specified. That is necessary to prevent hardware-driven power management from becoming overly aggressive on some systems and to prevent power management features leading to excessive latencies from being used in some cases. - Consolidation of the handling of ACPI hotplug notifications for device objects. This causes all device hotplug notifications to go through the root notify handler (that was executed for all of them anyway before) that propagates them to individual subsystems, if necessary, by executing callbacks provided by those subsystems (those callbacks are associated with struct acpi_device objects during device enumeration). As a result, the code in question becomes both smaller in size and more straightforward and all of those changes should not affect users. - ACPICA update, including fixes related to the handling of _PRT in cases when it is broken and the addition of "Windows 2013" to the list of supported "features" for _OSI (which is necessary to support systems that work incorrectly or don't even boot without it). Changes from Bob Moore and Lv Zheng. - Consolidation of ACPI _OST handling from Jiang Liu. - ACPI battery and AC fixes allowing unusual system configurations to be handled by that code from Alexander Mezin. - New device IDs for the ACPI LPSS driver from Chiau Ee Chew. - ACPI fan and thermal optimizations related to system suspend and resume from Aaron Lu. - Cleanups related to ACPI video from Jean Delvare. - Assorted ACPI fixes and cleanups from Al Stone, Hanjun Guo, Lan Tianyu, Paul Bolle, Tomasz Nowicki. - Intel RAPL (Running Average Power Limits) driver cleanups from Jacob Pan. - intel_pstate fixes and cleanups from Dirk Brandewie. - cpufreq fixes related to system suspend/resume handling from Viresh Kumar. - cpufreq core fixes and cleanups from Viresh Kumar, Stratos Karafotis, Saravana Kannan, Rashika Kheria, Joe Perches. - cpufreq drivers updates from Viresh Kumar, Zhuoyu Zhang, Rob Herring. - cpuidle fixes related to the menu governor from Tuukka Tikkanen. - cpuidle fix related to coupled CPUs handling from Paul Burton. - Asynchronous execution of all device suspend and resume callbacks, except for ->prepare and ->complete, during system suspend and resume from Chuansheng Liu. - Delayed resuming of runtime-suspended devices during system suspend for the PCI bus type and ACPI PM domain. - New set of PM helper routines to allow device runtime PM callbacks to be used during system suspend and resume more easily from Ulf Hansson. - Assorted fixes and cleanups in the PM core from Geert Uytterhoeven, Prabhakar Lad, Philipp Zabel, Rashika Kheria, Sebastian Capella. - devfreq fix from Saravana Kannan" * tag 'pm+acpi-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (162 commits) PM / devfreq: Rewrite devfreq_update_status() to fix multiple bugs PM / sleep: Correct whitespace errors in <linux/pm.h> intel_pstate: Set core to min P state during core offline cpufreq: Add stop CPU callback to cpufreq_driver interface cpufreq: Remove unnecessary braces cpufreq: Fix checkpatch errors and warnings cpufreq: powerpc: add cpufreq transition latency for FSL e500mc SoCs MAINTAINERS: Reorder maintainer addresses for PM and ACPI PM / Runtime: Update runtime_idle() documentation for return value meaning video / output: Drop display output class support fujitsu-laptop: Drop unneeded include acer-wmi: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / gpu / drm: Stop selecting VIDEO_OUTPUT_CONTROL ACPI / video: fix ACPI_VIDEO dependencies cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE} cpufreq: Do not allow ->setpolicy drivers to provide ->target cpufreq: arm_big_little: set 'physical_cluster' for each CPU cpufreq: arm_big_little: make vexpress driver depend on bL core driver ACPI / button: Add ACPI Button event via netlink routine ACPI: Remove duplicate definitions of PREFIX ...
2014-03-31Merge branch 'core-locking-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core locking updates from Ingo Molnar: "The biggest change is the MCS spinlock generalization changes from Tim Chen, Peter Zijlstra, Jason Low et al. There's also lockdep fixes/enhancements from Oleg Nesterov, in particular a false negative fix related to lockdep_set_novalidate_class() usage" * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits) locking/mutex: Fix debug checks locking/mutexes: Add extra reschedule point locking/mutexes: Introduce cancelable MCS lock for adaptive spinning locking/mutexes: Unlock the mutex without the wait_lock locking/mutexes: Modify the way optimistic spinners are queued locking/mutexes: Return false if task need_resched() in mutex_can_spin_on_owner() locking: Move mcs_spinlock.h into kernel/locking/ m68k: Skip futex_atomic_cmpxchg_inatomic() test futex: Allow architectures to skip futex_atomic_cmpxchg_inatomic() test Revert "sched/wait: Suppress Sparse 'variable shadowing' warning" lockdep: Change lockdep_set_novalidate_class() to use _and_name lockdep: Change mark_held_locks() to check hlock->check instead of lockdep_no_validate lockdep: Don't create the wrong dependency on hlock->check == 0 lockdep: Make held_lock->check and "int check" argument bool locking/mcs: Allow architecture specific asm files to be used for contended case locking/mcs: Order the header files in Kbuild of each architecture in alphabetical order sched/wait: Suppress Sparse 'variable shadowing' warning hung_task/Documentation: Fix hung_task_warnings description locking/mcs: Allow architectures to hook in to contended paths locking/mcs: Micro-optimize the MCS code, add extra comments ...
2014-03-20audit: anchor all pid references in the initial pid namespaceRichard Guy Briggs
Store and log all PIDs with reference to the initial PID namespace and use the access functions task_pid_nr() and task_tgid_nr() for task->pid and task->tgid. Cc: "Eric W. Biederman" <ebiederm@xmission.com> (informed by ebiederman's c776b5d2) Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
2014-03-19cpufreq: remove unused notifier: CPUFREQ_{SUSPENDCHANGE|RESUMECHANGE}Viresh Kumar
Two cpufreq notifiers CPUFREQ_RESUMECHANGE and CPUFREQ_SUSPENDCHANGE have not been used for some time, so remove them to clean up code a bit. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> [rjw: Changelog] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-03-17tty/serial: omap: empty the RX FIFO at the end of half-duplex TXDimitris Lampridis
Provided that the SER_RS485_RX_DURING_TX flag is not set, empty the RX FIFO to prevent reading back the transmitted data. Signed-off-by: Dimitris Lampridis <dlampridis@logikonlabs.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17tty/serial: omap: fix RX interrupt enable/disable in half-duplex TXDimitris Lampridis
Make sure that serial_omap_stop_rx() also disables RDI (Receiver Data Interrupt), otherwise the interrupt handler will call serial_omap_rdi() to read the new data, resulting in the transmission being echoed back. When the half-duplex transmission is complete, in order to reverse the effects of serial_omap_stop_rx(), we should re-enable: * the RX interrupts _without_ overwriting up->ier * the UART_LSR_DR bit of the up->port.read_status_mask Signed-off-by: Dimitris Lampridis <dlampridis@logikonlabs.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: sh-sci: Neaten dev_<level> usesJoe Perches
Add missing newlines and coalesce formats. Realign arguments. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: sh-sci: Replace hardcoded 3 by UART_PM_STATE_OFFGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Acked-by: Simon Horman <horms@verge.net.au> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: sh-sci: Add more register documentationGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Acked-by: Simon Horman <horms@verge.net.au> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: sh-sci: Remove useless castsGeert Uytterhoeven
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Acked-by: Simon Horman <horms@verge.net.au> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: sh-sci: Replace printk() by pr_*()Geert Uytterhoeven
Make banner const while we're at it Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Acked-by: Simon Horman <horms@verge.net.au> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial_core: Avoid NULL pointer dereference in uart_close()Geert Uytterhoeven
When unbinding a serial driver that's being used as a serial console, the kernel may crash with a NULL pointer dereference in a uart_*() function called from uart_close () (e.g. uart_flush_buffer() or uart_chars_in_buffer()). To fix this, let uart_close() check for port->count == 0. If this is the case, bail out early. Else tty_port_close_start() will make the port counts inconsistent, printing out warnings like tty_port_close_start: tty->count = 1 port count = 0. and tty_port_close_start: count = -1 and once uport == NULL, it will also crash. Also fix the related crash in pr_debug() by checking for a non-NULL uport first. Detailed description: On driver unbind, uart_remove_one_port() is called. Basically it; - marks the port dead, - calls tty_vhangup(), - sets state->uart_port = NULL. What will happen depends on whether the port is just in use by e.g. getty, or was also opened as a console. A. If the tty was not opened as a console: - tty_vhangup() will (in __tty_hangup()): - mark all file descriptors for this tty hung up by pointing them to hung_up_tty_fops, - call uart_hangup(), which sets port->count to 0. - A subsequent uart_open() (this may be through /dev/ttyS*, or through /dev/console if this is a serial console) will fail with -ENXIO as the port was marked dead, - uart_close() after the failed uart_open() will return early, as tty_hung_up_p() (called from tty_port_close_start()) will notice it was hung up. B. If the tty was also opened as a console: - tty_vhangup() will (in __tty_hangup()): - mark non-console file descriptors for this tty hung up by pointing them to hung_up_tty_fops, - NOT call uart_hangup(), but instead call uart_close() for every non-console file descriptor, so port->count will still have a non-zero value afterwards. - A subsequent uart_open() will fail with -ENXIO as the port was marked dead, - uart_close() after the failed uart_open() starts to misbehave: - tty_hung_up_p() will not notice it was hung up, - As port->count is non-zero, tty_port_close_start() will decrease port->count, making the tty and port counts inconsistent. Later, warnings like these will be printed: tty_port_close_start: tty->count = 1 port count = 0. and tty_port_close_start: count = -1 - If all of this happens after state->uart_port was set to zero, a NULL pointer dereference will happen. Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial_core: Get a reference for port->tty in uart_remove_one_port()Geert Uytterhoeven
Suggested-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-17serial: clps711x: Give a chance to perform useful tasks during wait loopAlexander Shiyan
This patch adds cond_sched() calls during wait loop to perform other tasks. Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>