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2009-06-11imx: serial: fix one bit field typeDaniel Glöckner
"have_rtscts" is assigned 1, while it is declared int:1, two's complement, which can hold 0 and -1 only. The code works, as the upper bits are cut off, and tests are done against 0 only. Nonetheless, correctly declaring the bit field as unsigned int:1 renders the code more robust. Signed-off-by: Daniel Glöckner <dg@emlix.com> Signed-off-by: Oskar Schirmer <os@emlix.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11imx: serial: fix whitespaces (no changes in functionality)Oskar Schirmer
Signed-off-by: Oskar Schirmer <os@emlix.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: use prepare/finish_waitJiri Slaby
Use prepare_to_wait and finish_wait instead of add_wait_queue and remove_wait_queue. This avoids us setting a task state. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: remove sleep_onJiri Slaby
Use wait_event instead of sleep_on in tty_block_til_ready. Wait for ASYNC_CLOSING flag being 0. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11sierra: driver interface blacklistingElina Pasheva
Interface blacklisting is necessary for non-serial interfaces that are handled by a different driver. The interface blacklisting is implemented in sierra driver per device. Each device in need of a blacklist has a static information array kept in the driver. This array contains the interface numbers that are blacklisted. The pointer for each blacklist array and the length of that blacklist are 'bundled' in data structure sierra_iface_info. A pointer to this information is set in id_table when the device is added to the id_table. The following is summary of changes we have made to sierra.c driver in this patch dealing with interface blacklisting support: - Added data structure sierra_iface_info and function is_blacklisted() to support blacklisting - Modified sierra_probe() to handle blacklisted interfaces accordingly - Improved comments in id_table - Added new device in id_table with blacklist interface support Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11sierra: driver urb handling improvementsElina Pasheva
[Folded from eight patches into one as the original set according to the author "All of the patches need to be applied to obtain a working product" so keeping them split seems unhelpful Merge fixes done versus other conflicting changes and moved the spin_lock_init from open to setup time -- Alan] Summary of the changes and code re-organization in this patch: - The memory for urbs is allocated and urbs are submitted only for the active interfaces (instead of pre-allocating these for all interfaces). This will save memory especially in the case of using composite devices. - The code has been re-organized and functionality has been extracted from sierra_startup(), sierra_shutdown(), sierra_open(), sierra_close() and added in helper functions sierra_release_urb(), sierra_stop_rx_urbs(), sierra_submit_rx_urbs() and sierra_setup_urb() - Added function sierra_release_urb() to free an urb and its transfer buffer. - Removed unecessary include file reference and comment. - Added function sierra_stop_rx_urbs() that takes care of the release of receive and interrupt urbs. This function is to be called by sierra_close() whenever an interface is de-activated. - Added new function sierra_submit_rx_urbs() that handles the submission of receive urbs and interrupt urbs (if any) during the interface activation. This function is to be called by sierra_open(). Added a second parameter to pass the memory allocation (as suggested by Oliver Neukum) so that this function can be used in post_reset() and resume(). - Added new function sierra_setup_urb() that contains the functionality to allocate an urb, fill bulk urb using the supplied memory allocation flag and release urb upon error. Added parameter so that the caller pass the memory allocation flag for flexibility. - Moved sierra_close() before sierra_open() to resolve dependencies introduced by the code reorganization. - Modified sierra_close() to call sierra_stop_rx_urbs() and sierra_release_urb() functions added in previous patch. - Modified sierra_open() to call sierra_setup_urb() and sierra_submit_rx_urbs() functions; note urbs are allocated and submitted for each activated interface. - Modified sierra_startup() so that allocation of urbs happens whenever an interface is activated (urb allocation is moved to sierra_open()). - Modified sierra_shutdown() so that urbs are freed whenever an interface is de-activated (urb freeing moved to sierra_close() as shown in previous patch from the series) - Removed unecessary data structure from sierra_port_private_data - Suppress an entry in logs by not re-submitting an urb when usb_submit_urb() returns -EPERM, as this shows that usb_kill_urb() is running (as suggested by Oliver Neukum) Signed-off-by: Elina Pasheva <epasheva@sierrawireless.com> Signed-off-by: Alan Cox <alan.cox@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: resolve some sierra breakageAlan Cox
The various merges into the sierra driver inadvertently undid commit 212b8f0c3f5a2280bfa1d6ab13a6fe98552becaa by Elina Pasheva <epasheva@sierrawireless.com>. Put it back so the OBEX port works again. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11timbuart: Fix the termios logicAlan Cox
The driver only handles speeds but it fails to return the current values for the hardware features it does not support. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11serial: Added Timberdale UART driverRichard Röjfors
Driver for the UART found in the Timberdale FPGA Signed-off-by: Richard Röjfors <richard.rojfors.ext@mocean-labs.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: Add URL for ttydev queueAlan Cox
Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11devpts: unregister the file system on errorAlan Cox
Closes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=13429 Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: Untangle termios and mm mutex dependenciesAlan Cox
Although this doesn't cause any problems it could potentially do so for future mmap using devices. No real work is needed to sort it out so untangle it before it causes problems Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: bfin_jtag_comm: emulate a TTY over the Blackfin EMUDAT/JTAG interfaceMike Frysinger
The Blackfin JTAG interface has a 4 byte generic data field (EMUDAT). With a little creative thinking, we can turn this into a TTY device. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11ftdi_sio: don't override modem bitsAlan Cox
The new open/close logic handles DTR and friends, so don't do it in our own open routine as well. Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: fix bluetooth scribbling on low latency flagsAlan Cox
Bluetooth shouldn't be doing this as most drivers don't support the flag, furthermore it shouldn't be needed with newer buffering. This becomes rather more visible as the locking fixes make the abuse of low_latency visible as spew on the users console/dmesg. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11ft232: support the ASYNC_LOW_LATENCY flagAlan Cox
This allows users to use the standard setserial command with this FT232 feature as well as obscure chip specific interfaces we have now. We keep track of and respect the sysfs value for non-low-latency cases. In theory we could do smart stuff with VTIME and the like but this seems of questionable worth. Closes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=9120 Signed-off-by: Alan Cox <alan@linux.intel.com) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11USB: CP210X Replace CP2101 with CP210xCraig Shelley
This patch replaces the string "CP2101" with "CP210x" within cp210x.c This is to reduce confusion about the fact that the driver is actually compatible with CP2101, CP2102 and CP2103 devices. Signed-off-by: Craig Shelley <craig@microtron.org.uk> (Fixed some collisions merging) Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11USB: CP210X Use official request code definitionsCraig Shelley
The CP210X driver was developed without official device specifications. This has lead to an incorrect assumption that all GET request codes are equal to the corresponding SET request code +1. This patch removes this incorrect assumption, and uses request code definitions based on the updated GPL driver from SiLabs. This modification is needed before extended functionality such as GPIO on CP2103 can be supported. Signed-off-by: Craig Shelley <craig@microtron.org.uk> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11USB: CP210X Add device IDsCraig Shelley
Signed-off-by: Craig Shelley <craig@microtron.org.uk> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: disable dma rx interrupt only rather than all irqsSonic Zhang
The UART RX handling code isn't exactly speeding, so don't go disabling all interrupts when processing the buffer. Just disable the relevant DMA interrupt. This greatly improves latency of the system when utilizing the UART. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: handle anomaly 05000231Sonic Zhang
05000231 - UART STB Bit Incorrectly Affects Receiver Setting For processors affected by this, we cannot safely allow CSTOPB to be set as the UART will then be unable to properly clock in bytes. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: annotate anomalies 05000215 and 05000099Sonic Zhang
Add some comments for how these anomalies are addressed: 05000215 - UART TX Interrupt Masked Erroneously We always clear ETBEI within last UART TX interrupt to end a string. It is always set when starting a new tx transfer. 05000099 - UART Line Status Register (UART_LSR) Bits Are Not Updated at the Same Time This anomaly affects driver only in POLL code where multi bits of UART_LSR are checked. It doesn't affect current bfin_5xx.c driver. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: handle irregular DMA register status in auto start modeSonic Zhang
This bug is caused by irregular behavior of DMA register CURR_X_COUNT and CURR_Y_COUNT when an auto restart uart rx DMA run to last byte in DMA buffer, trigger the interrupt and stay at this possiton. The status of current x and y is 0:7 instead of 512:8 or 0:8. The driver doesn't take care of this case when calculating the position. URL: http://blackfin.uclinux.org/gf/tracker/5063 Reported-by: Tomasz Motylewski <t.motylewski@bfad.de> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: fix missing new lines when under loadGraf Yang
Add a SSYNC() into bfin_serial_dma_tx_chars() to ensure DMA registers are written with new data otherwise we might miss a byte or two when the system is under load. PIO mode is OK though. Signed-off-by: Graf Yang <graf.yang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: fix baudrate for early_printkRobin Getz
Since we already setup the early console UART in arch/blackfin/kernel/early_printk.c, and common functions which are enabled from the .setup will override the proper settings later, don't fill in these structures. Otherwise we get mangled baudrate settings when using early_printk. Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin Serial Driver: fix error while transferring large filesSonic Zhang
Ignore receiving data if new position is in the same line of current buffer tail and is small. This should decrease overruns. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin SPORT UART: rewrite inline assemblyMike Frysinger
Hopefuly the new version is easier to read, but in the process it declares proper clobber lists and better constraints so that GCC can do a better job at allocating free registers. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin SPORT UART: fix data misses while using transmit frame syncMichael Hennerich
SPORT transmit frame sync (TFS) isn't used as an electrical signal during normal SPORT UART emulation. However, it is useful in EIA RS-485 emulation as RS-485 Transceiver Driver Enable DE strobe. This patch configures: TFS to be active high in order to drive an DE strobe of an eventually connected RS-485 Transceiver. Late frame sync mode (LATFS) gating the entire TX shift cycle. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Blackfin SPORT UART: fix typo in sport_set_termios prototypeMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11serial: add support for the TI AR7 internal UARTFlorian Fainelli
This patch adds support for the TI AR7 internal UART. Signed-off-by: Florian Fainelli <florian@openwrt.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11icom: fix compile errors when defining ICOM_TRACEBreno Leitao
As it is, defining ICOM_TRACE produces some compile errors, as "parameter name omitted" and "redefinition of ‘trace’" This patch removes the wrong trace definition. Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11parport_pc: clean up the modified while loops using forAlan Cox
And tidy up a few bits coding style detectors missed Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11parport_pc: Coding styleAlan Cox
Michael's patch fixed some of the coding style so the style is now inconsistent. Sort the rest out Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11parport_pc: Fix subscription bugsMichael Buesch
This patch fixes array subscription bugs in the parport_pc driver. drivers/parport/parport_pc.c: In function ‘parport_irq_probe’: drivers/parport/parport_pc.c:1589: warning: array subscript is above array bounds drivers/parport/parport_pc.c: In function ‘parport_pc_probe_port’: drivers/parport/parport_pc.c:1579: warning: array subscript is above array bounds The patch also fixes a few other array bugs, which the compiler was unable to find. Coding style violations are also fixed. Signed-off-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: simplify buffer allocator cleanupsAlan Cox
Having cleaned up the allocators we might as well remove the inline helpers for some of it Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: remove buffer special casingAlan Cox
Long long ago a 4K kmalloc allocated two pages so the tty layer used the page allocator, except on some machines where the page size was huge. This was removed from the core tty layer with the tty buffer re-implementation but not from tty_audit or the n_tty ldisc. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11icom: fixing a if clause spaghettiBreno Leitao
adapter->version can only be ADAPTER_V2 or ADAPTER_V1. So, that OR operand in the "if" clause is non-sense and can be removed. Signed-off-by: Breno Leitao <leitao@linux.vnet.ibm.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11jsm: correctly support multiple 4/8-port boardsAlexander Y. Fomichev
If there are more then one 4/8-port board jsm_uart_port_init allocate a line numbers of the second and further boards from range of previous one. This patch fixed the problem. Signed-off-by: Alexander Y. Fomichev <git.user@gmail.com> [printks fixed to add jsm: ] Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: iuu_phoenix: update version number.Olivier Bornet
Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: iuu_phoenix: set termios.Olivier Bornet
set_termios can now be used for setting the parity and the stopbits. This is needed to use with cards which use a different parity then the parity used at start (even). If the iuu_uart_baud function return an error, we will return the old_termios instead of the new one. Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch> This was then revamped to use the various helpers, not copy non-hardware bits any to add mark/space parity and csize reporting Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: iuu_phoenix: Fix stopbit when uart goes on.Olivier Bornet
Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: iuu_phoenix: fix locking.Olivier Bornet
Bring in the relevant bits of the 0.9 vendor driver. Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: bring ldisc into CodingStyleAlan Cox
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: Move ldisc_flushAlan Cox
We have a tty_ldisc file now so put tty_ldisc_flush in the right place Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: rewrite the ldisc lockingAlan Cox
There are several pretty much unfixable races in the old ldisc code, especially with respect to pty behaviour and also to hangup. It's easier to rewrite the code than simply try and patch it up. This patch - splits the ldisc from the tty (so we will be able to refcount it more cleanly later) - introduces a mutex lock for ldisc changing on an active device - fixes the complete mess that hangup caused - implements hopefully correct setldisc/close/hangup locking There are still some problems around pty pairs that have always been there but at least it is now possible to understand the code and fix further problems. This fixes the following known bugs - hang up can leak ldisc references - hang up may not call open/close on ldisc in a matched way - pty/tty pairs can deadlock during an ldisc change - reading the ldisc proc files can cause every ldisc to be loaded and probably a few other of the mysterious ldisc race reports. I'm sure it also adds the odd new one. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: Extract various bits of ldisc codeAlan Cox
Before trying to tackle the ldisc bugs the code needs to be a good deal more readable, so do the simple extractions of routines first. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: Fix oops when scanning the polling list for kgdbAlan Cox
Costantino Leandro found a bug in tty_find_polling_driver and provided a patch that fixed the crash but not the underlying bug. This fixes the underlying bug where the list walk corrupts the values it is using on a match but then reuses them if the open fails. Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11pty: Fix a commentAlan Cox
We fixed the globals, so now fix the comment Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11serial: update maintainers fileAlan Cox
Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11tty: throttling race fixAlan Cox
The tty throttling code can race due to the lock drops. It takes very high loads but this has been observed and verified by Rob Duncan. The basic problem is that on an SMP box we can go CPU #1 CPU #2 need to throttle ? suppose we should buffer space cleared are we throttled yes ? - unthrottle call throttle method This changeet take the termios lock to protect against this. The termios lock isn't the initial obvious candidate but many implementations of throttle methods already need to poke around their own termios structures (and nobody really locks them against a racing change of flow control). This does mean that anyone who is setting tty->low_latency = 1 and then calling tty_flip_buffer_push from their unthrottle method is going to end up collapsing in a pile of locks. However we've removed all the known bogus users of low_latency = 1 and such use isn't safe anyway for other reasons so catching it would be an improvement. Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>