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2010-12-01Merge branch 'sh/cachetlb' into sh-fixes-for-linusPaul Mundt
2010-12-01sh: Assume new page cache pages have dirty dcache lines.Paul Mundt
This follows the ARM change c01778001a4f5ad9c62d882776235f3f31922fdd ("ARM: 6379/1: Assume new page cache pages have dirty D-cache") for the same rationale: There are places in Linux where writes to newly allocated page cache pages happen without a subsequent call to flush_dcache_page() (several PIO drivers including USB HCD). This patch changes the meaning of PG_arch_1 to be PG_dcache_clean and always flush the D-cache for a newly mapped page in update_mmu_cache(). This addresses issues seen with executing binaries from MMC, in addition to some of the other HCDs that don't explicitly do cache management for their pipe-in buffers. Requested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-11-30Merge branch 'drm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 * 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: drm/radeon/kms: add workaround for dce3 ddc line vbios bug drm/radeon/kms: fix interlaced and doublescan handling drm/radeon/kms: fix typos in disabled vbios code Revert "drm/i915/dp: use VBT provided eDP params if available" drm/i915: Clear pfit registers when not used by any outputs drm: record monitor status in output_poll_execute drm: Set connector DPMS status to ON in drm_crtc_helper_set_config drm/i915: fix regression due to ba3d8d749b01548b9 Revert "drm/radeon/kms: fix typo in r600 cs checker" drm/i915/sdvo: Always add a 30ms delay to make SDVO TV detection reliable MAINTAINERS: INTEL DRM DRIVERS list (intel-gfx) is subscribers-only drm/i915/sdvo: Always fallback to querying the shared DDC line drm/i915: Handle pagefaults in execbuffer user relocations drm/i915/sdvo: Only enable HDMI encodings only if the commandset is supported drm/radeon/kms: fix resume regression for some r5xx laptops drm/radeon/kms: fix regression in rs4xx i2c setup drm/i915: Only save/restore cursor regs if !KMS drm/i915: Prevent integer overflow when validating the execbuffer
2010-12-01drm/radeon/kms: add workaround for dce3 ddc line vbios bugAlex Deucher
fixes: https://bugzilla.kernel.org/show_bug.cgi?id=23752 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc:stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-12-01drm/radeon/kms: fix interlaced and doublescan handlingAlex Deucher
Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-12-01drm/radeon/kms: fix typos in disabled vbios codeAlex Deucher
6xx/7xx was hitting the wrong BUS_CNTL reg and bits. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-12-01Merge remote branch 'intel/drm-intel-fixes' of /ssd/git/drm-next into drm-fixesDave Airlie
* 'intel/drm-intel-fixes' of /ssd/git/drm-next: Revert "drm/i915/dp: use VBT provided eDP params if available" drm/i915: Clear pfit registers when not used by any outputs drm/i915: fix regression due to ba3d8d749b01548b9
2010-11-30Merge branch 'for_linus' of git://github.com/at91linux/linux-2.6-at91Linus Torvalds
* 'for_linus' of git://github.com/at91linux/linux-2.6-at91: at91/board-yl-9200: fix typo in video support atmel_spi: fix warning In function 'atmel_spi_dma_map_xfer' at91/picotux200: remove commenting usb device and dataflash support at91: rename rm9200ek and rm9200dk board file name at91rm9200ek: fix warning: 'ek_mmc_data' defined but not used at91rm9200dk: fix warning: 'dk_mmc_data' defined but not used at91: Convert remaining boards to new-style UART initialization at91: merge all at91rm9200 defconfig in one single file
2010-11-30exec: copy-and-paste the fixes into compat_do_execve() pathsOleg Nesterov
Note: this patch targets 2.6.37 and tries to be as simple as possible. That is why it adds more copy-and-paste horror into fs/compat.c and uglifies fs/exec.c, this will be cleanuped later. compat_copy_strings() plays with bprm->vma/mm directly and thus has two problems: it lacks the RLIMIT_STACK check and argv/envp memory is not visible to oom killer. Export acct_arg_size() and get_arg_page(), change compat_copy_strings() to use get_arg_page(), change compat_do_execve() to do acct_arg_size(0) as do_execve() does. Add the fatal_signal_pending/cond_resched checks into compat_count() and compat_copy_strings(), this matches the code in fs/exec.c and certainly makes sense. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-30exec: make argv/envp memory visible to oom-killerOleg Nesterov
Brad Spengler published a local memory-allocation DoS that evades the OOM-killer (though not the virtual memory RLIMIT): http://www.grsecurity.net/~spender/64bit_dos.c execve()->copy_strings() can allocate a lot of memory, but this is not visible to oom-killer, nobody can see the nascent bprm->mm and take it into account. With this patch get_arg_page() increments current's MM_ANONPAGES counter every time we allocate the new page for argv/envp. When do_execve() succeds or fails, we change this counter back. Technically this is not 100% correct, we can't know if the new page is swapped out and turn MM_ANONPAGES into MM_SWAPENTS, but I don't think this really matters and everything becomes correct once exec changes ->mm or fails. Reported-by: Brad Spengler <spender@grsecurity.net> Reviewed-and-discussed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-30serial: mfd: adjust the baud rate settingFeng Tang
Previous baud rate setting code only has been tested with 3.5M/9600/ 115200/230400/460800 bps, and recently we got a 3M bps device to test, which needs to modify current MUL register setting, and with this patch 2.5M/2M/1.5M/1M/0.5M should also work as they just use a MUL value scale down from 3M's. Also got some reference register setting from silicon guys for different baud rates, which tries to keep the pre-scalar register value to 16. Signed-off-by: Feng Tang <feng.tang@intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30Merge branch 'for-greg' of git://gitorious.org/usb/usb into workGreg Kroah-Hartman
2010-11-30Merge branch 'for-usb-linus' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into work
2010-11-30cifs: fix parsing of hostname in dfs referralsJeff Layton
The DFS referral parsing code does a memchr() call to find the '\\' delimiter that separates the hostname in the referral UNC from the sharename. It then uses that value to set the length of the hostname via pointer subtraction. Instead of subtracting the start of the hostname however, it subtracts the start of the UNC, which causes the code to pass in a hostname length that is 2 bytes too long. Regression introduced in commit 1a4240f4. Reported-and-Tested-by: Robbert Kouprie <robbert@exx.nl> Signed-off-by: Jeff Layton <jlayton@redhat.com> Cc: Wang Lei <wang840925@gmail.com> Cc: David Howells <dhowells@redhat.com> Cc: stable@kernel.org Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30USB: fix autosuspend bug in usb-serialAlan Stern
This patch (as1437) fixes a bug in the usb-serial autosuspend handling. Since the usb-serial core now has autosuspend support, it must set the .supports_autosuspend member in every serial driver it registers. Otherwise the usb_autopm_get_interface() call won't work. This fixes Bugzilla #23012. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> CC: stable@kernel.org Reported-by: Kevin Smith <thirdwiggin@gmail.com> Reported-and-tested-by: Simon Gerber <gesimu@gmail.com> Reported-and-tested-by: Matteo Croce <matteo@openwrt.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30USB: ehci: disable LPM and PPCD for nVidia MCP89 chipsBrian J. Tarricone
Tested on MacBookAir3,1. Without this, we get EPROTO errors when fetching device config descriptors. Signed-off-by: Brian Tarricone <brian@tarricone.org> Reported-by: Benoit Gschwind <gschwind@gnu-log.net> Tested-by: Edgar Hucek <gimli@dark-green.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30USB: serial: ftdi_sio: Vardaan USB RS422/485 converter PID addedJacques Viviers
Add the PID for the Vardaan Enterprises VEUSB422R3 USB to RS422/485 converter. It uses the same chip as the FTDI_8U232AM_PID 0x6001. This should also work with the stable branches for: 2.6.31, 2.6.32, 2.6.33, 2.6.34, 2.6.35, 2.6.36 Signed-off-by: Jacques Viviers <jacques.viviers@gmail.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30USB: yurex: add .llseek fop to file_operationsTomoki Sekiyama
Default llseek operation behavior was changed by the patch named "vfs: make no_llseek the default" after the yurex driver had been merged, so the llseek to yurex is now ignored. This patch add llseek fop with default_llseek to yurex driver to catch up to the change. Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30USB: ftdi_sio: Add ID for RT Systems USB-29B radio cableMichael Stuermer
Another variant of the RT Systems programming cable for ham radios. Signed-off-by: Michael Stuermer <ms@mallorn.de> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-30NFS: Fix a readdirplus bugTrond Myklebust
When comparing filehandles in the helper nfs_same_file(), we should not be using 'strncmp()': filehandles are not null terminated strings. Instead, we should just use the existing helper nfs_compare_fh(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-30at91/board-yl-9200: fix typo in video supportJean-Christophe PLAGNIOL-VILLARD
for the epson frambuffer support it's CONFIG_FB_S1D13XXX not CONFIG_FB_S1D135XX Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-11-30atmel_spi: fix warning In function 'atmel_spi_dma_map_xfer'Jean-Christophe PLAGNIOL-VILLARD
passing argument 2 of 'dma_map_single' discards qualifiers from pointer target type Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-11-30at91/picotux200: remove commenting usb device and dataflash supportJean-Christophe PLAGNIOL-VILLARD
as based on http://www.picotux.com/pt200/picotux200.pdf these board does not have such I/O Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-11-30at91: rename rm9200ek and rm9200dk board file nameJean-Christophe PLAGNIOL-VILLARD
to be a few more concistant with the other boards as ek is for evaluation kit and dk for development kit Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Andrew Victor <linux@maxim.org.za>
2010-11-30at91rm9200ek: fix warning: 'ek_mmc_data' defined but not usedJean-Christophe PLAGNIOL-VILLARD
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Andrew Victor <linux@maxim.org.za>
2010-11-30at91rm9200dk: fix warning: 'dk_mmc_data' defined but not usedJean-Christophe PLAGNIOL-VILLARD
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Andrew Victor <linux@maxim.org.za>
2010-11-30at91: Convert remaining boards to new-style UART initializationJean-Christophe PLAGNIOL-VILLARD
Convert the following AT91RM9200-based boards to the new-style UART initialization: - Ajeco 1ARM Single Board Computer - Sperry-Sun KAFA board - picotux 200 Remove the deprecated at91_init_serial Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Andrew Victor <linux@maxim.org.za>
2010-11-30regulator: fix kernel-doc for set_consumer_device_supplyRandy Dunlap
Fix kernel-doc warning for set_consumer_device_supply(): Warning(drivers/regulator/core.c:912): missing initial short description on line: * set_consumer_device_supply: Bind a regulator to a symbolic supply Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Liam Girdwood <lrg@slimlogic.co.uk> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: enable supply regulator only when use count is zeroBengt Jonsson
Supply regulators are disabled only when the last reference count is removed on the child regulator (the use count goes from 1 to 0). This patch changes the behaviour of enable so the supply regulator is enabled only when the use count of the child regulator goes from 0 to 1. Signed-off-by: Bengt Jonsson <bengt.g.jonsson@stericsson.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: twl-regulator - fix twlreg_set_modeAxel Lin
The Singular Message is 16 bits: DEV_GRP[15:13] MT[12] RES_ID[11:4] RES_STATE[3:0] Current implementation return immedially after sucessfuly write MSB part. To properly set mode, we need to write the complete message ( MSB and LSB ). In twl.h, now we have defines for PM Master module register offsets, use it instead of hard coded 0x15/0x16. Use "message & 0xff" to ensure we send correct value for LSB. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Tested-by: Lesly Arackal Manuel <leslyam@ti.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: lock supply in regulator enableMattias Wallin
This patch add locks around regulator supply enable. Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: Return proper error for regulator_register()Axel Lin
Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: Ensure enough delay time for enabling regulatorAxel Lin
Integer division will truncate the result, this patch ensures we have enough delay time for enabling regulator. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: Remove a redundant device_remove_file call in create_regulatorAxel Lin
We already have device_remove_file() in error path, no need to call it before goto link_name_err. Signed-off-by: Axel Lin <axel.lin@gmail.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: Staticise mc13783_powermisc_rmw()Mark Brown
It is not used outside this driver so no need to make the symbol global. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Alberto Panizzo <maramaopercheseimorto@gmail.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30regulator: regulator disable supply fixMattias Wallin
This patch fixes a disable failure when regulator supply is used. A while loop in regulator disable checks for supply pointer != NULL but the pointer is not always updated, resulting in the while loop running too many times causing a disable failure. Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2010-11-30at91: merge all at91rm9200 defconfig in one single fileEric Benard
About all options present in each file are activated in the single file. Signed-off-by: Eric Benard <eric@eukrea.com> Tested-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2010-11-30Revert "drm/i915/dp: use VBT provided eDP params if available"Chris Wilson
This reverts commit 869184a675662bddcdf76c5b95665272facff2b8. This is required for the Sony Vaio Jesse was working on at the time, but breaks most other eDP machines - machines that were working in earlier kernels. Reported-and-tested-by: Dave Airlie <airlied@redhat.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=31188 Tested-by: Zhao Jian <jian.j.zhao@intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2010-11-30cifs: display fsc in /proc/mountsSuresh Jayaraman
Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30cifs: enable fscache iff fsc mount option is used explicitlySuresh Jayaraman
Currently, if CONFIG_CIFS_FSCACHE is set, fscache is enabled on files opened as read-only irrespective of the 'fsc' mount option. Fix this by enabling fscache only if 'fsc' mount option is specified explicitly. Remove an extraneous cFYI debug message and fix a typo while at it. Reported-by: Jeff Layton <jlayton@redhat.com> Acked-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30cifs: allow fsc mount option only if CONFIG_CIFS_FSCACHE is setSuresh Jayaraman
Currently, it is possible to specify 'fsc' mount option even if CONFIG_CIFS_FSCACHE has not been set. The option is being ignored silently while the user fscache functionality to work. Fix this by raising error when the CONFIG option is not set. Reported-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Suresh Jayaraman <sjayaraman@suse.de> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30cifs: Handle extended attribute name cifs_acl to generate cifs acl blob (try #4)Shirish Pargaonkar
Add extended attribute name system.cifs_acl Get/generate cifs/ntfs acl blob and hand over to the invoker however it wants to parse/process it under experimental configurable option CIFS_ACL. Do not get CIFS/NTFS ACL for xattr for attribute system.posix_acl_access Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-30cifs: Misc. cleanup in cifsacl handling [try #4]Shirish Pargaonkar
Change the name of function mode_to_acl to mode_to_cifs_acl. Handle return code in functions mode_to_cifs_acl and cifs_acl_to_fattr. Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com>
2010-11-29Linux 2.6.37-rc4Linus Torvalds
2010-11-29Merge branch 'merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc: Use call_rcu_sched() for pagetables
2010-11-30powerpc: Use call_rcu_sched() for pagetablesPeter Zijlstra
PowerPC relies on IRQ-disable to guard against RCU quiecent states, use the appropriate RCU call version. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-11-29Revert "debug_locks: set oops_in_progress if we will log messages."Dave Airlie
This reverts commit e0fdace10e75dac67d906213b780ff1b1a4cc360. On-list discussion seems to suggest that the robustness fixes for printk make this unnecessary and DaveM has also agreed in person at Kernel Summit and on list. The main problem with this code is once we hit a lockdep splat we always keep oops_in_progress set, the console layer uses oops_in_progress with KMS to decide when it should be showing the oops and not showing X, so it causes problems around suspend/resume time when a userspace resume can cause a console switch away from X, only if oops_in_progress is set (which is what we want if an oops actually is in progress, but not because we had a lockdep splat 2 days prior). Cc: David S Miller <davem@davemloft.net> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-29TTY: open/hangup race fixupJiri Slaby
Like in the "TTY: don't allow reopen when ldisc is changing" patch, this one fixes a TTY WARNING as described in the option 1) there: 1) __tty_hangup from tty_ldisc_hangup to tty_ldisc_enable. During this section tty_lock is held. However tty_lock is temporarily dropped in the middle of the function by tty_ldisc_hangup. The fix is to introduce a new flag which we set during the unlocked window and check it in tty_reopen too. The flag is TTY_HUPPING and is cleared after TTY_HUPPED is set. While at it, remove duplicate TTY_HUPPED set_bit. The one after calling ops->hangup seems to be more correct. But anyway, we hold tty_lock, so there should be no difference. Also document the function it does that kind of crap. Nicely reproducible with two forked children: static void do_work(const char *tty) { if (signal(SIGHUP, SIG_IGN) == SIG_ERR) exit(1); setsid(); while (1) { int fd = open(tty, O_RDWR|O_NOCTTY); if (fd < 0) continue; if (ioctl(fd, TIOCSCTTY)) continue; if (vhangup()) continue; close(fd); } exit(0); } Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: <Valdis.Kletnieks@vt.edu> Reported-by: Kyle McMartin <kyle@mcmartin.ca> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-29TTY: don't allow reopen when ldisc is changingJiri Slaby
There are many WARNINGs like the following reported nowadays: WARNING: at drivers/tty/tty_io.c:1331 tty_open+0x2a2/0x49a() Hardware name: Latitude E6500 Modules linked in: Pid: 1207, comm: plymouthd Not tainted 2.6.37-rc3-mmotm1123 #3 Call Trace: [<ffffffff8103b189>] warn_slowpath_common+0x80/0x98 [<ffffffff8103b1b6>] warn_slowpath_null+0x15/0x17 [<ffffffff8128a3ab>] tty_open+0x2a2/0x49a [<ffffffff810fd53f>] chrdev_open+0x11d/0x146 ... This means tty_reopen is called without TTY_LDISC set. For further considerations, note tty_lock is held in tty_open. TTY_LDISC is cleared in: 1) __tty_hangup from tty_ldisc_hangup to tty_ldisc_enable. During this section tty_lock is held. However tty_lock is temporarily dropped in the middle of the function by tty_ldisc_hangup. 2) tty_release via tty_ldisc_release till the end of tty existence. If tty->count <= 1, tty_lock is taken, TTY_CLOSING bit set and then tty_ldisc_release called. tty_reopen checks TTY_CLOSING before checking TTY_LDISC. 3) tty_set_ldisc from tty_ldisc_halt to tty_ldisc_enable. We: * take tty_lock, set TTY_LDISC_CHANGING, put tty_lock * call tty_ldisc_halt (clear TTY_LDISC), tty_lock is _not_ held * do some other work * take tty_lock, call tty_ldisc_enable (set TTY_LDISC), put tty_lock I cannot see how 2) can be a problem, as there I see no race. OTOH, 1) and 3) can happen without problems. This patch the case 3) by checking TTY_LDISC_CHANGING along with TTY_CLOSING in tty_reopen. 1) will be fixed in the following patch. Nicely reproducible with two processes: while (1) { fd = open("/dev/ttyS1", O_RDWR); if (fd < 0) { warn("open"); continue; } close(fd); } -------- while (1) { fd = open("/dev/ttyS1", O_RDWR); ld1 = 0; ld2 = 2; while (1) { ioctl(fd, TIOCSETD, &ld1); ioctl(fd, TIOCSETD, &ld2); } close(fd); } Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: <Valdis.Kletnieks@vt.edu> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-11-29NET: wan/x25, fix ldisc->open retvalJiri Slaby
We should never return positive values from ldisc->open, tty layer doesn't (and never did) expect that. If we do that, weird things like warnings in tty_ldisc_close happen. Not sure if dev->base_addr is used somehow now. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Alan Cox <alan@linux.intel.com> Cc: Andrew Hendry <andrew.hendry@gmail.com> Cc: linux-x25@vger.kernel.org Tested-by: Sergey Lapin <slapin@ossfans.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>