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2009-10-07Blackfin: fix missed cache config renamesGraf Yang
Looks like the big Kconfig cache split/rename missed one spot in the SMP cache lock headers. Signed-off-by: Graf Yang <graf.yang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-07Blackfin: cplbinfo: drop d_path() hacksMike Frysinger
The cplbinfo was using d_path() to figure out which cpu/cplb was being parsed. As Al pointed out, this isn't exactly reliable as it assumes the static VFS path to be unchanged, and it's just poor form. So use the proc_create_data() to properly (and internally) pass the exact cpu/cplb requested to the parser function. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-07Blackfin: asm/irq.h: pull in mach/anomaly.h for anomaly definesMike Frysinger
The asm/irq.h header uses anomaly defines, but doesn't make sure to explicitly include the anomaly header for them. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-07Blackfin: BF51x: add PTP MMR definesBarry Song
2009-10-07Blackfin: mass clean up of copyright/licensing infoRobin Getz
Bill Gatliff & David Brownell pointed out we were missing some copyrights, and licensing terms in some of the files in ./arch/blackfin, so this fixes things, and cleans them up. It also removes: - verbose GPL text(refer to the top level ./COPYING file) - file names (you are looking at the file) - bug url (it's in the ./MAINTAINERS file) - "or later" on GPL-2, when we did not have that right It also allows some Blackfin-specific assembly files to be under a BSD like license (for people to use them outside of Linux). Signed-off-by: Robin Getz <robin.getz@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-07Blackfin: convert to use arch_gettimeoffset()john stultz
Convert Blackfin to use GENERIC_TIME via the arch_getoffset() infrastructure, reducing the amount of arch specific code we need to maintain. I've taken my best swing at converting this, but I'm not 100% confident I got it right. My cross-compiler is now out of date (gcc4.2) so I wasn't able to check if it compiled. Any assistance from arch maintainers or testers to get this merged would be great. Signed-off-by: John Stultz <johnstul@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6: Revert "ide: try to use PIO Mode 0 during probe if possible" ide: use printk_once
2009-10-05Merge branch 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
* 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: add support for change_pte mmu notifiers KVM: MMU: add SPTE_HOST_WRITEABLE flag to the shadow ptes KVM: MMU: dont hold pagecount reference for mapped sptes pages KVM: Prevent overflow in KVM_GET_SUPPORTED_CPUID KVM: VMX: flush TLB with INVEPT on cpu migration KVM: fix LAPIC timer period overflow KVM: s390: fix memsize >= 4G KVM: SVM: Handle tsc in svm_get_msr/svm_set_msr correctly KVM: SVM: Fix tsc offset adjustment when running nested
2009-10-05Merge branch 'fixes-for-linus' of git://git.monstr.eu/linux-2.6-microblazeLinus Torvalds
* 'fixes-for-linus' of git://git.monstr.eu/linux-2.6-microblaze: microblaze: Clear sticky FSR register after saving it to func parametr microblaze: UMS is used only for MMU kernel
2009-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6: sparc: using HZ needs an include of linux/param.h sparc32: convert to asm-generic/hardirq.h sparc64: Cache per-cpu %pcr register value in perf code. sparc64: Fix comment typo in perf_event.c sparc64: Minor coding style fixups in perf code. sparc64: Add a basic conflict engine in preparation for multi-counter support. sparc64: Increase vmalloc size to fix percpu regressions. sparc64: Add initial perf event conflict resolution and checks. sparc: Niagara1 perf event support. sparc: Add Niagara2 HW cache event support. sparc: Support all ultra3 and ultra4 derivatives. sparc: Support HW cache events.
2009-10-05iSCSI/iBFT: use proper address translationJan Beulich
In virtual environments (namely, Xen Dom0) virt <-> phys and virt <-> isa-bus translations cannot be freely interchanged (and even outside such environments it is not really correct to do so). When looking at memory below 1M, the latter translations should always be used. iscsi_ibft_find.c part from: Martin Wilck <martin.wilck@ts.fujitsu.com>. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Peter Jones <pjones@redhat.com> Signed-off-by: Konrad Rzeszutek Wilk <ketuzsezs@darnok.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-05Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf tools: Run generate-cmdlist.sh properly perf_event: Clean up perf_event_init_task() perf_event: Fix event group handling in __perf_event_sched_*() perf timechart: Add a power-only mode perf top: Add poll_idle to the skip list
2009-10-05Merge branch 'timers-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: hrtimer: Remove overly verbose "switch to high res mode" message
2009-10-05Merge branch 'tracing-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: kmemtrace: Fix up tracer registration tracing: Fix infinite recursion in ftrace_update_pid_func()
2009-10-05Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: Don't leak 64-bit kernel register values to 32-bit processes x86, SLUB: Remove unused CONFIG FAST_CMPXCHG_LOCAL x86: earlyprintk: Fix regression to handle serial,ttySn as 1 arg x86: Don't generate cmpxchg8b_emu if CONFIG_X86_CMPXCHG64=y x86: Fix csum_ipv6_magic asm memory clobber x86: Optimize cmpxchg64() at build-time some more
2009-10-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68knommu: fix rename of pt_regs offset defines breakage m68knommu: remove duplicated #include m68knommu: show KiB rather than pages in "Freeing initrd memory:" message
2009-10-05microblaze: Clear sticky FSR register after saving it to func parametrMichal Simek
Previous patch d63678d607d0e37ec7abe5ceb545d7e8aab956a4 clear it for noMMU kernel. This one do it for MMU. Correct noMMU version Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-10-05microblaze: UMS is used only for MMU kernelMichal Simek
Signed-off-by: Michal Simek <monstr@monstr.eu>
2009-10-05sparc: using HZ needs an include of linux/param.hStephen Rothwell
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-04Revert "ide: try to use PIO Mode 0 during probe if possible"David S. Miller
This reverts commit 6029336426a2b43e4bc6f4a84be8789a047d139e. Based upon a report by David Fries, wherein his system hangs on bootup with sis5513 controller, right after the CDROM is registered by ide-cd.c and the TOC is first read. Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-04Linux 2.6.32-rc3Linus Torvalds
I'm skipping -rc2 because the -rc1 Makefile mistakenly said -rc2, so in order to avoid confusion, I'm jumping from -rc1 to -rc3. That way, when 'uname' (or an oops report) says 2.6.32-rc2, there's no confusion about whether people perhaps meant -rc1 or -rc2.
2009-10-04headers: remove sched.h from poll.hAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-04Merge branch 'acpi-pad' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'acpi-pad' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: acpi_pad: build only on X86 ACPI: create Processor Aggregator Device driver Fixup trivial conflicts in MAINTAINERS file.
2009-10-04Merge branch 'sfi-release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-sfi-2.6 * 'sfi-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-sfi-2.6: SFI: remove __init from sfi_verify_table SFI: fix section mismatch warnings in sfi_core.c
2009-10-04Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: ACPI: EC: Don't parse DSDT for EC early init on Compal ACPI: EC: Rewrite DMI checks ACPI: dock: fix "sibiling" typo ACPI: kill overly verbose "throttling states" log messages ACPI: Fix bound checks for copy_from_user in the acpi /proc code ACPI: fix bus scanning memory leaks ACPI: EC: Restart command even if no interrupts from EC sony-laptop: Don't unregister the SPIC driver if it wasn't registered sony-laptop: remove _INI call at init time sony-laptop: SPIC unset IRQF_SHARED, set IRQF_DISABLED sony-laptop: remove device_ctrl and the SPIC mini drivers
2009-10-04Merge branch 'i2c-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging * 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: macintosh: Don't assume i2c device probing always succeeds i2c: Hide probe errors caused by ACPI resource conflicts i2c: Minor documentation update mfd: AB3100 drop unused module parameters Staging: IIO: tsl2561: Drop unused module parameters leds: leds-pca9532 - Drop unused module parameters ltc4215/ltc4245: Discard obsolete detect methods ds2482: Discard obsolete detect method max6875: Discard obsolete detect method i2c: Move misc devices documentation
2009-10-04macintosh: Don't assume i2c device probing always succeedsJean Delvare
If i2c device probing fails, then there is no driver to dereference after calling i2c_new_device(). Stop assuming that probing will always succeed, to avoid NULL pointer dereferences. We have an easier access to the driver anyway. Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Tim Shepard <shep@alum.mit.edu> Cc: Colin Leroy <colin@colino.net>
2009-10-04i2c: Hide probe errors caused by ACPI resource conflictsJean Delvare
When an ACPI resource conflict is detected, error messages are already printed by ACPI. There's no point in causing the driver core to print more error messages, so return one of the error codes for which no message is printed. This fixes bug #14293: http://bugzilla.kernel.org/show_bug.cgi?id=14293 Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-10-04i2c: Minor documentation updateJean Delvare
The sysfs path to i2c adapters has changed recently, update the documentation to reflect that change. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-10-04mfd: AB3100 drop unused module parametersJean Delvare
The I2C_CLIENT_INSMOD_1 macro is only useful for i2c drivers which implement device detection. The ab3100 driver doesn't, so there is no point in calling it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Cc: Samuel Ortiz <sameo@linux.intel.com>
2009-10-04Staging: IIO: tsl2561: Drop unused module parametersJean Delvare
The I2C_CLIENT_INSMOD macro is only useful for i2c drivers which implement device detection. The tsl2561 driver doesn't, so there is no point in calling it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Jonathan Cameron <jic23@cam.ac.uk>
2009-10-04leds: leds-pca9532 - Drop unused module parametersJean Delvare
The I2C_CLIENT_INSMOD_1 macro is only useful for i2c drivers which implement device detection. The leds-pca9532 driver doesn't, so there is no point in calling it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Riku Voipio <riku.voipio@iki.fi>
2009-10-04ltc4215/ltc4245: Discard obsolete detect methodsJean Delvare
There is no point in implementing a detect callback for the LTC4215 and LTC4245, as these devices can't be detected. It was there solely to handle "force" module parameters to instantiate devices, but now we have a better sysfs interface that can do the same. So we can get rid of the ugly module parameters and the detect callbacks. This shrinks the binary module sizes by 36% and 46%, respectively. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Ira W. Snyder <iws@ovro.caltech.edu>
2009-10-04ds2482: Discard obsolete detect methodJean Delvare
There is no point in implementing a detect callback for the DS2482, as this device can't be detected. It was there solely to handle "force" module parameters to instantiate devices, but now we have a better sysfs interface that can do the same. So we can get rid of the ugly module parameters and the detect callback. This shrinks the binary module size by 21%. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Ben Gardner <gardner.ben@gmail.com>
2009-10-04max6875: Discard obsolete detect methodJean Delvare
There is no point in implementing a detect callback for the MAX6875, as this device can't be detected. It was there solely to handle "force" module parameters to instantiate devices, but now we have a better sysfs interface that can do the same. So we can get rid of the ugly module parameters and the detect callback. This basically divides the binary module size by 2. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Ben Gardner <gardner.ben@gmail.com>
2009-10-04i2c: Move misc devices documentationJean Delvare
Some times ago the eeprom and max6875 drivers moved to drivers/misc/eeprom, but their documentation did not follow. It's finally time to get rid of Documentation/i2c/chips. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Ben Gardner <gardner.ben@gmail.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2009-10-04Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (41 commits) Revert "Seperate read and write statistics of in_flight requests" cfq-iosched: don't delay async queue if it hasn't dispatched at all block: Topology ioctls cfq-iosched: use assigned slice sync value, not default cfq-iosched: rename 'desktop' sysfs entry to 'low_latency' cfq-iosched: implement slower async initiate and queue ramp up cfq-iosched: delay async IO dispatch, if sync IO was just done cfq-iosched: add a knob for desktop interactiveness Add a tracepoint for block request remapping block: allow large discard requests block: use normal I/O path for discard requests swapfile: avoid NULL pointer dereference in swapon when s_bdev is NULL fs/bio.c: move EXPORT* macros to line after function Add missing blk_trace_remove_sysfs to be in pair with blk_trace_init_sysfs cciss: fix build when !PROC_FS block: Do not clamp max_hw_sectors for stacking devices block: Set max_sectors correctly for stacking devices cciss: cciss_host_attr_groups should be const cciss: Dynamically allocate the drive_info_struct for each logical drive. cciss: Add usage_count attribute to each logical drive in /sys ...
2009-10-04Revert "Seperate read and write statistics of in_flight requests"Jens Axboe
This reverts commit a9327cac440be4d8333bba975cbbf76045096275. Corrado Zoccolo <czoccolo@gmail.com> reports: "with 2.6.32-rc1 I started getting the following strange output from "iostat -kx 2": Linux 2.6.31bisect (et2) 04/10/2009 _i686_ (2 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 10,70 0,00 3,16 15,75 0,00 70,38 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 18,22 0,00 0,67 0,01 14,77 0,02 43,94 0,01 10,53 39043915,03 2629219,87 sdb 60,89 9,68 50,79 3,04 1724,43 50,52 65,95 0,70 13,06 488437,47 2629219,87 avg-cpu: %user %nice %system %iowait %steal %idle 2,72 0,00 0,74 0,00 0,00 96,53 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 avg-cpu: %user %nice %system %iowait %steal %idle 6,68 0,00 0,99 0,00 0,00 92,33 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 avg-cpu: %user %nice %system %iowait %steal %idle 4,40 0,00 0,73 1,47 0,00 93,40 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await svctm %util sda 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 0,00 100,00 sdb 0,00 4,00 0,00 3,00 0,00 28,00 18,67 0,06 19,50 333,33 100,00 Global values for service time and utilization are garbage. For interval values, utilization is always 100%, and service time is higher than normal. I bisected it down to: [a9327cac440be4d8333bba975cbbf76045096275] Seperate read and write statistics of in_flight requests and verified that reverting just that commit indeed solves the issue on 2.6.32-rc1." So until this is debugged, revert the bad commit. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-04cfq-iosched: don't delay async queue if it hasn't dispatched at allJens Axboe
We cannot delay for the first dispatch of the async queue if it hasn't dispatched at all, since that could present a local user DoS attack vector using an app that just did slow timed sync reads while filling memory. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-10-04KVM: add support for change_pte mmu notifiersIzik Eidus
this is needed for kvm if it want ksm to directly map pages into its shadow page tables. [marcelo: cast pfn assignment to u64] Signed-off-by: Izik Eidus <ieidus@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: MMU: add SPTE_HOST_WRITEABLE flag to the shadow ptesIzik Eidus
this flag notify that the host physical page we are pointing to from the spte is write protected, and therefore we cant change its access to be write unless we run get_user_pages(write = 1). (this is needed for change_pte support in kvm) Signed-off-by: Izik Eidus <ieidus@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: MMU: dont hold pagecount reference for mapped sptes pagesIzik Eidus
When using mmu notifiers, we are allowed to remove the page count reference tooken by get_user_pages to a specific page that is mapped inside the shadow page tables. This is needed so we can balance the pagecount against mapcount checking. (Right now kvm increase the pagecount and does not increase the mapcount when mapping page into shadow page table entry, so when comparing pagecount against mapcount, you have no reliable result.) Signed-off-by: Izik Eidus <ieidus@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: Prevent overflow in KVM_GET_SUPPORTED_CPUIDAvi Kivity
The number of entries is multiplied by the entry size, which can overflow on 32-bit hosts. Bound the entry count instead. Reported-by: David Wagner <daw@cs.berkeley.edu> Cc: stable@kernel.org Signed-off-by: Avi Kivity <avi@redhat.com>
2009-10-04KVM: VMX: flush TLB with INVEPT on cpu migrationMarcelo Tosatti
It is possible that stale EPTP-tagged mappings are used, if a vcpu migrates to a different pcpu. Set KVM_REQ_TLB_FLUSH in vmx_vcpu_load, when switching pcpus, which will invalidate both VPID and EPT mappings on the next vm-entry. Cc: stable@kernel.org Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: fix LAPIC timer period overflowAurelien Jarno
Don't overflow when computing the 64-bit period from 32-bit registers. Fixes sourceforge bug #2826486. Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Cc: stable@kernel.org Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: s390: fix memsize >= 4GChristian Borntraeger
commit 628eb9b8a8f3 KVM: s390: streamline memslot handling introduced kvm_s390_vcpu_get_memsize. This broke guests >=4G, since this function returned an int. This patch changes the return value to a long. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com>
2009-10-04KVM: SVM: Handle tsc in svm_get_msr/svm_set_msr correctlyJoerg Roedel
When running nested we need to touch the l1 guests tsc_offset. Otherwise changes will be lost or a wrong value be read. Cc: stable@kernel.org Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-04KVM: SVM: Fix tsc offset adjustment when running nestedJoerg Roedel
When svm_vcpu_load is called while the vcpu is running in guest mode the tsc adjustment made there is lost on the next emulated #vmexit. This causes the tsc running backwards in the guest. This patch fixes the issue by also adjusting the tsc_offset in the emulated hsave area so that it will not get lost. Cc: stable@kernel.org Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-10-03Merge branch 'for-linus' of git://www.linux-m32r.org/git/takata/linux-2.6_devLinus Torvalds
* 'for-linus' of git://www.linux-m32r.org/git/takata/linux-2.6_dev: m32r: Fix IPI function calls for SMP m32r: Fix set_memory() for DISCONTIGMEM m32r: add rtc_lock variable m32r: define ioread* and iowrite* macros m32r: export delay loop symbols m32r: fix tme_handler
2009-10-03tty: Avoid dropping ldisc_mutex over hangup tty re-initializationLinus Torvalds
A couple of people have hit the WARN_ON() in drivers/char/tty_io.c, tty_open() that is unhappy about seeing the tty line discipline go away during the tty hangup. See for example http://bugzilla.kernel.org/show_bug.cgi?id=14255 and the reason is that we do the tty_ldisc_halt() outside the ldisc_mutex in order to be able to flush the scheduled work without a deadlock with vhangup_work. However, it turns out that we can solve this particular case by - using "cancel_delayed_work_sync()" in tty_ldisc_halt(), which waits for just the particular work, rather than synchronizing with any random outstanding pending work. This won't deadlock, since the buf.work we synchronize with doesn't care about the ldisc_mutex, it just flushes the tty ldisc buffers. - realize that for this particular case, we don't need to wait for any hangup work, because we are inside the hangup codepaths ourselves. so as a result we can just drop the flush_scheduled_work() entirely, and then move the tty_ldisc_halt() call to inside the mutex. That way we never expose the partially torn down ldisc state to tty_open(), and hold the ldisc_mutex over the whole sequence. Reported-by: Ingo Molnar <mingo@elte.hu> Reported-by: Heinz Diehl <htd@fancy-poultry.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>