linux/drivers/char
Linus Torvalds 202c4675c5 pty_write: don't do a tty_wakeup() when the buffers are full
Commit ac89a9174 ("pty: don't limit the writes to 'pty_space()' inside
'pty_write()'") removed the pty_space() checking, in order to let the
regular tty buffer code limit the buffering itself.

That was all good, but as a subtle side effect it meant that we'd be
doing a tty_wakeup() even in the case where the buffers were all filled
up, and didn't actually make any progress on the write.

Which sounds innocuous, but it interacts very badly with the ppp_async
code, which has an infinite loop in ppp_async_push() that tries to push
out data to the tty.  When we call tty_wakeup(), that loop ends up
thinking that progress was made (see the subtle interactions between
XMIT_WAKEUP and 'tty_stuffed' for details).  End result: one unhappy ppp
user.

Fixed by noticing when tty_insert_flip_string() didn't actually do
anything, and then not doing any more processing (including, very much
not calling tty_wakeup()).

Bisected-and-tested-by: Peter Volkov <pva@gentoo.org>
Cc: stable@kernel.org (2.6.31)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-18 07:05:58 -07:00
..
agp Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2009-09-15 09:51:09 -07:00
hw_random MIPS: hw_random: Add hardware RNG for Octeon SOCs. 2009-09-17 20:07:51 +02:00
ip2 tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
ipmi ipmi: remove driver_data direct access of struct device 2009-06-15 21:30:27 -07:00
mwave mwave: struct device - replace bus_id with dev_name(), dev_set_name() 2009-01-06 10:44:38 -08:00
pcmcia hdlc: convert to netdev_tx_t 2009-09-01 01:13:31 -07:00
rio headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
tpm TPM: Fixup boot probe timeout for tpm_tis driver 2009-09-10 19:19:09 +10:00
xilinx_hwicap xilinx_hwicap: remove improper wording in license statement 2008-12-17 11:23:07 -08:00
.gitignore
ChangeLog
Kconfig MIPS: Update VR41xx GPIO driver to use gpiolib 2009-07-03 15:45:25 +01:00
Makefile MIPS: Update VR41xx GPIO driver to use gpiolib 2009-07-03 15:45:25 +01:00
amiserial.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
apm-emulation.c APM emulation: Notify about all suspend events, not just APM invoked ones (v2) 2008-07-16 23:27:02 +02:00
applicom.c applicom: Auto-load applicom module when device opened. 2009-04-06 14:36:30 -07:00
applicom.h
bfin-otp.c
bfin_jtag_comm.c bfin_jtag_comm: clean up printk usage 2009-06-22 11:32:23 -07:00
briq_panel.c briq_panel: BKL pushdown 2008-06-20 14:05:55 -06:00
bsr.c powerpc/BSR: Fix BSR to allow mmap of small BSR on 64k kernel 2009-06-26 14:37:26 +10:00
cd1865.h
consolemap.c consolemap: indentation & braces disagree - reindent 2009-01-06 15:59:30 -08:00
cp437.uni unicode table for cp437 2008-12-13 11:25:49 -08:00
cs5535_gpio.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
cyclades.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
defkeymap.c_shipped
defkeymap.map
digi1.h
digiFep1.h
digiPCI.h
ds1302.c rtc: use bcd2bin/bin2bcd 2008-10-20 08:52:41 -07:00
ds1620.c [ARM] netwinder: clean up GPIO naming 2008-12-13 09:12:07 +00:00
dsp56k.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
dtlk.c dtlk: off by one in {read,write}_tts() 2009-06-19 16:46:06 -07:00
efirtc.c drivers/char/efirtc.c: removed duplicated #include 2008-08-04 16:59:56 -07:00
epca.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
epca.h epca: use tty_port 2008-07-20 17:12:36 -07:00
epcaconfig.h
esp.c esp: fix section mismatch warning 2009-04-07 08:31:03 -07:00
generic_nvram.c powerpc/nvram: Enable use Generic NVRAM driver for different size chips 2009-09-11 16:02:11 +10:00
generic_serial.c tty: Remove some pointless casts 2009-01-02 10:19:40 -08:00
genrtc.c genrtc: BKL pushdown 2008-06-20 14:05:57 -06:00
hangcheck-timer.c
hpet.c irq: change ACPI GSI APIs to also take a device argument 2009-04-28 12:21:17 +02:00
hvc_beat.c powerpc/cell: Use correct types in beat files 2009-01-08 16:25:16 +11:00
hvc_console.c hvc_console: Drop unnecessary NULL test 2009-08-20 10:29:23 +10:00
hvc_console.h powerpc: Make open count variables signed in hvcs/hvsi/hvc_console 2008-12-03 21:04:13 +11:00
hvc_irq.c hvc_console: Call free_irq() only if request_irq() was successful 2009-01-13 14:48:01 +11:00
hvc_iseries.c drivers/hvc: Add missing __devexit_p() 2009-06-16 14:15:44 +10:00
hvc_iucv.c [S390] proper use of device register 2009-09-11 10:29:45 +02:00
hvc_rtas.c
hvc_udbg.c powerpc: udbg-based backend for hvc_console 2008-11-19 16:04:25 +11:00
hvc_vio.c hvc_console: Add __init and __exit to hvc_vio 2009-08-28 14:24:11 +10:00
hvc_xen.c hvc_console: Add a hangup notifier for backends 2008-10-22 10:59:54 +11:00
hvcs.c Merge commit 'origin/master' into next 2009-06-18 11:16:55 +10:00
hvsi.c powerpc/hvsi: Avoid calculating possibly-invalid address 2009-08-20 10:29:28 +10:00
i8k.c i8k: Add Dell Vostro systems 2009-01-02 10:28:32 -08:00
isicom.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
istallion.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
keyboard.c Input: keyboard - remove warning about raw mode not supported 2009-04-20 21:21:24 -07:00
lp.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
mbcs.c
mbcs.h
mem.c mem_class: fix bug 2009-09-15 09:50:47 -07:00
misc.c Driver Core: misc: add nodename support for misc devices. 2009-06-15 21:30:25 -07:00
mmtimer.c mmtimer: Push BKL down into the ioctl handler 2008-07-17 11:34:49 -07:00
moxa.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
moxa.h
mspec.c mspec: convert nopfn to fault 2008-07-24 10:47:14 -07:00
mxser.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
mxser.h
n_hdlc.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
n_r3964.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
n_tty.c n_tty: do O_ONLCR translation as a single write 2009-09-05 12:46:07 -07:00
nozomi.c tty: fix chars_in_buffers 2009-07-20 16:38:43 -07:00
nsc_gpio.c
nvram.c [PATCH] nvram - convert PRINT_PROC to seq_file 2008-11-11 09:56:00 +00:00
nwbutton.c
nwbutton.h
nwflash.c [ARM] netwinder: clean up GPIO naming 2008-12-13 09:12:07 +00:00
pc8736x_gpio.c pc8736x_gpio: add support for PC87365 chips 2008-10-20 08:52:40 -07:00
ppdev.c ppdev: reduce kernel log spam 2009-06-18 13:03:54 -07:00
ps3flash.c ps3flash: Always read chunks of 256 KiB, and cache them 2009-06-15 16:47:27 +10:00
pty.c pty_write: don't do a tty_wakeup() when the buffers are full 2009-09-18 07:05:58 -07:00
random.c random: Add optional continuous repetition test to entropy store based rngs 2009-06-18 19:50:21 +08:00
raw.c vfs: Rename generic_file_aio_write_nolock 2009-09-14 17:08:15 +02:00
riscom8.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
riscom8.h tty: add more tty_port fields 2008-07-20 17:12:38 -07:00
riscom8_reg.h
rocket.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
rocket.h tty: rocketport uses different port flags to everyone else 2009-01-02 10:19:39 -08:00
rocket_int.h tty: rocketport uses different port flags to everyone else 2009-01-02 10:19:39 -08:00
rtc.c RTC: Remove the BKL. 2009-01-08 16:44:03 -07:00
scc.h m68k: atari - Rename "mfp" to "st_mfp" 2009-02-22 09:23:02 -08:00
scx200_gpio.c Add a bunch of cycle_kernel_lock() calls 2008-06-20 14:05:53 -06:00
selection.c tty: rewrite the ldisc locking 2009-06-11 08:51:01 -07:00
ser_a2232.c m68k: ser_a2232 - Kill warn_unused_result warnings 2009-01-12 20:56:39 +01:00
ser_a2232.h
ser_a2232fw.ax
ser_a2232fw.h
serial167.c cleanup console_print() 2009-09-14 17:41:42 -07:00
snsc.c device create: char: convert device_create_drvdata to device_create 2008-10-16 09:24:42 -07:00
snsc.h
snsc_event.c
sonypi.c Rationalize fasync return values 2009-03-16 08:34:35 -06:00
specialix.c specialix.c: convert nested spin_lock_irqsave to spin_lock 2009-07-20 16:38:43 -07:00
specialix_io8.h tty: add more tty_port fields 2008-07-20 17:12:38 -07:00
stallion.c tty: Add carrier processing on close to the tty_port core 2009-06-11 08:50:56 -07:00
sx.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
sx.h
sxboards.h
sxwindow.h
synclink.c hdlc: convert to netdev_tx_t 2009-09-01 01:13:31 -07:00
synclink_gt.c hdlc: convert to netdev_tx_t 2009-09-01 01:13:31 -07:00
synclinkmp.c hdlc: convert to netdev_tx_t 2009-09-01 01:13:31 -07:00
sysrq.c debug lockups: Improve lockup detection, fix generic arch fallback 2009-08-03 09:56:52 +02:00
tb0219.c Update Yoichi Yuasa's e-mail address 2009-07-03 15:45:29 +01:00
tlclk.c tlckl: BKL pushdown 2008-06-20 14:05:51 -06:00
toshiba.c
tty_audit.c tty: remove buffer special casing 2009-06-11 08:51:02 -07:00
tty_buffer.c pty: avoid forcing 'low_latency' tty flag 2009-07-29 12:15:56 -07:00
tty_io.c tty: fix sanity check 2009-06-16 12:01:16 -07:00
tty_ioctl.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00
tty_ldisc.c tty: make sure to flush any pending work when halting the ldisc 2009-08-25 09:12:43 -07:00
tty_port.c tty_port: Fix return on interrupted use 2009-07-17 08:50:43 -07:00
vc_screen.c vc: create vcs(a) devices for consoles 2009-07-20 16:38:43 -07:00
viotape.c tape: beyond ARRAY_SIZE of viocd_diskinfo 2009-06-02 10:32:34 +10:00
virtio_console.c virtio: find_vqs/del_vqs virtio operations 2009-06-12 22:16:36 +09:30
vme_scc.c m68k: vme_scc - Kill warn_unused_result warnings 2009-01-12 20:56:38 +01:00
vt.c sparc: Kill PROM console driver. 2009-09-15 17:04:38 -07:00
vt_ioctl.c headers: smp_lock.h redux 2009-07-12 12:22:34 -07:00