The smp_call_function can be passed a wait parameter telling it to
wait for all the functions running on other CPUs to complete before
returning, or to return without waiting. Unfortunately, this is
currently just a suggestion and not manditory. That is, the
smp_call_function can decide not to return and wait instead.
The reason for this is because it uses kmalloc to allocate storage
to send to the called CPU and that CPU will free it when it is done.
But if we fail to allocate the storage, the stack is used instead.
This means we must wait for the called CPU to finish before
continuing.
Unfortunatly, some callers do no abide by this hint and act as if
the non-wait option is mandatory. The MTRR code for instance will
deadlock if the smp_call_function is set to wait. This is because
the smp_call_function will wait for the other CPUs to finish their
called functions, but those functions are waiting on the caller to
continue.
This patch changes the generic smp_call_function code to use per cpu
variables if the allocation of the data fails for a single CPU call. The
smp_call_function_many will fall back to the smp_call_function_single
if it fails its alloc. The smp_call_function_single is modified
to not force the wait state.
Since we now are using a single data per cpu we must synchronize the
callers to prevent a second caller modifying the data before the
first called IPI functions complete. To do so, I added a flag to
the call_single_data called CSD_FLAG_LOCK. When the single CPU is
called (which can be called when a many call fails an alloc), we
set the LOCK bit on this per cpu data. When the caller finishes
it clears the LOCK bit.
The caller must wait till the LOCK bit is cleared before setting
it. When it is cleared, there is no IPI function using it.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix debug_smp_processor_id() for CONFIG_CPUMASK_OFFSTACK=y
The scheduler now uses the new cpumask API, which deals up to
nr_cpumask_bits, whereas the API used NR_CPUS bits.
If CONFIG_CPUMASK_OFFSTACK=y these two are not equal, so the top bits
are undefined. Leading to bug 12518 "BUG: using smp_processor_id() in
preemptible [00000000] code: dellWirelessCtl/..."
The fix is simple: use the modern API in the check.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With print-fatal-signals=1 on a kernel with CONFIG_PREEMPT=y, sending an
unexpected signal to a process causes a BUG: using smp_processor_id() in
preemptible code.
get_signal_to_deliver() releases the siglock before calling
print_fatal_signal(), which calls show_regs(), which calls
smp_processor_id(), which is not supposed to be called from a
preemptible thread.
Make sure show_regs() runs with preemption disabled.
Signed-off-by: Ed Swierk <eswierk@aristanetworks.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
klist.c: bit 0 in pointer can't be used as flag
debugfs: introduce stub for debugfs_create_size_t() when DEBUG_FS=n
sysfs: fix problems with binary files
PNP: fix broken pnp lowercasing for acpi module aliases
driver core: Convert '/' to '!' in dev_set_name()
swab.h seems to have been missed during the header merge.
Add conditionals similar to byteorder.h and remove the
now unnecessary byteorder_no/mm.h
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/i915: Fix cursor physical address choice to match the 2D driver.
drm: stash AGP include under the do-we-have-AGP ifdef
drm: don't whine about not reading EDID data
drm/i915: hook up LVDS DPMS property
drm/i915: remove unnecessary debug output in KMS init
i915: fix freeing path for gem phys objects.
drm: create mode_config idr lock
drm: fix leak of device mappings since multi-master changes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI hotplug: fix lock imbalance in pciehp
PCI PM: Restore standard config registers of all devices early
PCI/MSI: bugfix/utilize for msi_capability_init()
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
i.MX31: framebuffer driver
i.MX31: Image Processing Unit DMA and IRQ drivers
dmaengine: add async_tx_clear_ack() macro
dmaengine: dma_issue_pending_all == nop when CONFIG_DMA_ENGINE=n
dmaengine: kill some dubious WARN_ONCEs
fsldma: print correct IRQ on mpc83xx
fsldma: check for NO_IRQ in fsl_dma_chan_remove()
dmatest: Use custom map/unmap for destination buffer
fsldma: use a valid 'device' for dma_pool_create
dmaengine: fix dependency chaining
* 'sh/for-2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (22 commits)
dma-coherent: Restore dma_alloc_from_coherent() large alloc fall back policy.
dma-coherent: per-device coherent area is in pages, not bytes.
sh: fix unaligned and nonexistent address handling
nommu: Stub in vm_map_ram()/vm_unmap_ram()/vm_unmap_aliases().
sh: fix sh-sci / early printk build on sh7723
sh: export the sh7343 JPU to user space
sh: update defconfigs.
serial: sh-sci: Fix up SH7720/SH7721 SCI build.
sh: Kill off obsolete busses from arch/sh/Kconfig.
sh: sh7785lcr/highlander/hp6xx need linux/irq.h.
sh: Migo-R MMC support using spi_gpio and mmc_spi.
sh: ap325rxa MMC support using spi_gpio and mmc_spi
sh: mach-x3proto: needs linux/irq.h.
sh: Drop the BKL from sys_execve() on SH-5.
sh: convert rsk7203 to use smsc911x.
sh: convert magicpanelr2 platform to use smsc911x.
sh: convert ap325rxa platform to use smsc911x.
sh: mach-migor: Add tw9910 support.
sh: mach-migor: Delete soc_camera_platform setup.
sh: mach-migor: Add ov772x support.
...
* 'Kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/misc: (36 commits)
fs/Kconfig: move 9p out
fs/Kconfig: move afs out
fs/Kconfig: move coda out
fs/Kconfig: move the rest of ncpfs out
fs/Kconfig: move smbfs out
fs/Kconfig: move sunrpc out
fs/Kconfig: move nfsd out
fs/Kconfig: move nfs out
fs/Kconfig: move ufs out
fs/Kconfig: move sysv out
fs/Kconfig: move romfs out
fs/Kconfig: move qnx4 out
fs/Kconfig: move hpfs out
fs/Kconfig: move omfs out
fs/Kconfig: move minix out
fs/Kconfig: move vxfs out
fs/Kconfig: move squashfs out
fs/Kconfig: move cramfs out
fs/Kconfig: move efs out
fs/Kconfig: move bfs out
...
If userspace supplies an invalid pointer to a read() of an inotify
instance, the inotify device's event list mutex is unlocked twice.
This causes an unbalance which effectively leaves the data structure
unprotected, and we can trigger oopses by accessing the inotify
instance from different tasks concurrently.
The best fix (contributed largely by Linus) is a total rewrite
of the function in question:
On Thu, Jan 22, 2009 at 7:05 AM, Linus Torvalds wrote:
> The thing to notice is that:
>
> - locking is done in just one place, and there is no question about it
> not having an unlock.
>
> - that whole double-while(1)-loop thing is gone.
>
> - use multiple functions to make nesting and error handling sane
>
> - do error testing after doing the things you always need to do, ie do
> this:
>
> mutex_lock(..)
> ret = function_call();
> mutex_unlock(..)
>
> .. test ret here ..
>
> instead of doing conditional exits with unlocking or freeing.
>
> So if the code is written in this way, it may still be buggy, but at least
> it's not buggy because of subtle "forgot to unlock" or "forgot to free"
> issues.
>
> This _always_ unlocks if it locked, and it always frees if it got a
> non-error kevent.
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Robert Love <rlove@google.com>
Cc: <stable@kernel.org>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use '%zu' to print out a size_t variable, not '%d'. Another case of the
"let's keep at least Linus' defconfig compile warningless" rule.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
debugobjects: add and use INIT_WORK_ON_STACK
rcu: remove duplicate CONFIG_RCU_CPU_STALL_DETECTOR
relay: fix lock imbalance in relay_late_setup_files
oprofile: fix uninitialized use of struct op_entry
rcu: move Kconfig menu
softlock: fix false panic which can occur if softlockup_thresh is reduced
rcu: add __cpuinit to rcu_init_percpu_data()
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
hrtimers: fix inconsistent lock state on resume in hres_timers_resume
time-sched.c: tick_nohz_update_jiffies should be static
locking, hpet: annotate false positive warning
kernel/fork.c: unused variable 'ret'
itimers: remove the per-cpu-ish-ness
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (29 commits)
xen: unitialised return value in xenbus_write_transaction
x86: fix section mismatch warning
x86: unmask CPUID levels on Intel CPUs, fix
x86: work around PAGE_KERNEL_WC not getting WC in iomap_atomic_prot_pfn.
x86: use standard PIT frequency
xen: handle highmem pages correctly when shrinking a domain
x86, mm: fix pte_free()
xen: actually release memory when shrinking domain
x86: unmask CPUID levels on Intel CPUs
x86: add MSR_IA32_MISC_ENABLE bits to <asm/msr-index.h>
x86: fix PTE corruption issue while mapping RAM using /dev/mem
x86: mtrr fix debug boot parameter
x86: fix page attribute corruption with cpa()
Revert "x86: signal: change type of paramter for sys_rt_sigreturn()"
x86: use early clobbers in usercopy*.c
x86: remove kernel_physical_mapping_init() from init section
fix: crash: IP: __bitmap_intersects+0x48/0x73
cpufreq: use work_on_cpu in acpi-cpufreq.c for drv_read and drv_write
work_on_cpu: Use our own workqueue.
work_on_cpu: don't try to get_online_cpus() in work_on_cpu.
...
* 'for-linus' of git://oss.sgi.com/xfs/xfs:
Long btree pointers are still 64 bit on disk
[XFS] Remove the rest of the macro-to-function indirections.
xfs: sanity check attr fork size
xfs: fix bad_features2 fixups for the root filesystem
xfs: add a lock class for group/project dquots
xfs: lockdep annotations for xfs_dqlock2
xfs: add a separate lock class for the per-mount list of dquots
xfs: use mnt_want_write in compat_attrmulti ioctl
xfs: fix dentry aliasing issues in open_by_handle
Move fuse_copy_finish() to before calling fuse_notify_poll_wakeup().
This is not a big issue because fuse_notify_poll_wakeup() should be
atomic, but it's cleaner this way, and later uses of notification will
need to be able to finish the copying before performing some actions.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
If a fuse filesystem is unmounted but the device file descriptor
remains open and a new mount reuses the old device number, then the
mount fails with EEXIST and the following warning is printed in the
kernel log:
WARNING: at fs/sysfs/dir.c:462 sysfs_add_one+0x35/0x3d()
sysfs: duplicate filename '0:15' can not be created
The cause is that the bdi belonging to the fuse filesystem was
destoryed only after the device file was released. Fix this by
calling bdi_destroy() from fuse_put_super() instead.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
Fix the leaking file reference if allocation or initialization of
fuse_conn failed.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
ff is set to NULL and then dereferenced on line 65. Compile tested only.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
The return value of xenbus_write_transaction can be uninitialised in
the success case leading to the userspace xenstore utilities failing.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Here function vmi_activate calls a init function activate_vmi , which
causes the following section mismatch warnings:
LD arch/x86/kernel/built-in.o
WARNING: arch/x86/kernel/built-in.o(.text+0x13ba9): Section mismatch
in reference from the function vmi_activate() to the function
.init.text:vmi_time_init()
The function vmi_activate() references
the function __init vmi_time_init().
This is often because vmi_activate lacks a __init
annotation or the annotation of vmi_time_init is wrong.
WARNING: arch/x86/kernel/built-in.o(.text+0x13bd1): Section mismatch
in reference from the function vmi_activate() to the function
.devinit.text:vmi_time_bsp_init()
The function vmi_activate() references
the function __devinit vmi_time_bsp_init().
This is often because vmi_activate lacks a __devinit
annotation or the annotation of vmi_time_bsp_init is wrong.
WARNING: arch/x86/kernel/built-in.o(.text+0x13bdb): Section mismatch
in reference from the function vmi_activate() to the function
.devinit.text:vmi_time_ap_init()
The function vmi_activate() references
the function __devinit vmi_time_ap_init().
This is often because vmi_activate lacks a __devinit
annotation or the annotation of vmi_time_ap_init is wrong.
Fix it by marking vmi_activate() as __init too.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix boot hang on pre-model-15 Intel CPUs
rdmsrl_safe() does not work in very early bootup code yet, because we
dont have the pagefault handler installed yet so exception section
does not get parsed. rdmsr_safe() will just crash and hang the bootup.
So limit the MSR_IA32_MISC_ENABLE MSR read to those CPU types that
support it.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In the absence of PAT, PAGE_KERNEL_WC ends up mapping to a memory type that
gets UC behavior even in the presence of a WC MTRR covering the area in
question. By swapping to PAGE_KERNEL_UC_MINUS, we can get the actual
behavior the caller wanted (WC if you can manage it, UC otherwise).
This recovers the 40% performance improvement of using WC in the DRM
to upload vertex data.
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
IRQF_DISABLED is not guaranteed for shared IRQs. I think power_changed_isr
doesn't need it anyway, as it only fires a timer.
This patch enables IRQF_SAMPLE_RANDOM instead.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
the RDC and ELAN platforms use slighly different PIT clocks, resulting in
a timex.h hack that changes PIT_TICK_RATE during build time. But if a
tester enables any of these platform support .config options, the PIT
will be miscalibrated on standard PC platforms.
So use one frequency - in a subsequent patch we'll add a quirk to allow
x86 platforms to define different PIT frequencies.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 1058a75f07 ("xen: actually release
memory when shrinking domain") causes a crash if the page being released
is a highmem page.
If a page is highmem then there is no need to unmap it.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On -rt we were seeing spurious bad page states like:
Bad page state in process 'firefox'
page:c1bc2380 flags:0x40000000 mapping:c1bc2390 mapcount:0 count:0
Trying to fix it up, but a reboot is needed
Backtrace:
Pid: 503, comm: firefox Not tainted 2.6.26.8-rt13 #3
[<c043d0f3>] ? printk+0x14/0x19
[<c0272d4e>] bad_page+0x4e/0x79
[<c0273831>] free_hot_cold_page+0x5b/0x1d3
[<c02739f6>] free_hot_page+0xf/0x11
[<c0273a18>] __free_pages+0x20/0x2b
[<c027d170>] __pte_alloc+0x87/0x91
[<c027d25e>] handle_mm_fault+0xe4/0x733
[<c043f680>] ? rt_mutex_down_read_trylock+0x57/0x63
[<c043f680>] ? rt_mutex_down_read_trylock+0x57/0x63
[<c0218875>] do_page_fault+0x36f/0x88a
This is the case where a concurrent fault already installed the PTE and
we get to free the newly allocated one.
This is due to pgtable_page_ctor() doing the spin_lock_init(&page->ptl)
which is overlaid with the {private, mapping} struct.
union {
struct {
unsigned long private;
struct address_space *mapping;
};
spinlock_t ptl;
struct kmem_cache *slab;
struct page *first_page;
};
Normally the spinlock is small enough to not stomp on page->mapping, but
PREEMPT_RT=y has huge 'spin'locks.
But lockdep kernels should also be able to trigger this splat, as the
lock tracking code grows the spinlock to cover page->mapping.
The obvious fix is calling pgtable_page_dtor() like the regular pte free
path __pte_free_tlb() does.
It seems all architectures except x86 and nm10300 already do this, and
nm10300 doesn't seem to use pgtable_page_ctor(), which suggests it
doesn't do SMP or simply doesnt do MMU at all or something.
Signed-off-by: Peter Zijlstra <a.p.zijlsta@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>
Add wrapper functions for the following compat system calls:
* readahead
* sendfile64
* tkill
* tgkill
* keyctl
This ensures that the high order bits of the parameter registers are correctly
sign extended.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Precreate stop_machine threads in case the machine supports ETR/STP.
Otherwise we might deadlock if a time sync operation gets scheduled
and the creation of stop_machine threads would cause disk I/O.
This is just the minimal fix.
The real fix would be to only precreate stop_machine threads if
ETR/STP is actually used. But that would be a rather large and
complicated patch.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
On (initial) cpu hotplug the lowcore values for user_timer and
system_timer don't get initialized like they would get on each
process schedule.
On initial start of secondary cpus this leads to the situation
where per thread user/system_timer values are larger than the
corresponding contents of the lowcore. When later calculating
time spent in user/system context the result can be negative.
So for cpu hotplug we should manually initialize lowcore values.
Fixes this bug:
Kernel BUG at 000ec080 [verbose debug info unavailable]
fixpoint divide exception: 0009 [#1] PREEMPT SMP
Modules linked in:
CPU: 10 Not tainted 2.6.28 #4
Process sysctl (pid: 975, task: 3fa752e0, ksp: 3fbebca0)
Krnl PSW : 070c1000 800ec080 (show_stat+0x390/0x5fc)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:1 PM:0
Krnl GPRS: 7fffffff fefc7ce5 3faec080 003879ae
00000001 01388000 7fffffff 01388000
00000000 00000000 0049ad50 3fbebcf8
01388000 002f51a8 800ec1fe 3fbebcf8
Krnl Code: 800ec076: 9001b188 stm %r0,%r1,392(%r11)
800ec07a: 9801b0c0 lm %r0,%r1,192(%r11)
800ec07e: 1d05 dr %r0,%r5
>800ec080: 9001b0c0 stm %r0,%r1,192(%r11)
800ec084: 5860b0c4 l %r6,196(%r11)
800ec088: 1806 lr %r0,%r6
800ec08a: 8c800001 srdl %r8,1
800ec08e: 1d87 dr %r8,%r7
Call Trace:
([<00000000000ec1ee>] show_stat+0x4fe/0x5fc)
[<00000000000c13e8>] seq_read+0xc4/0x3ac
[<00000000000e4796>] proc_reg_read+0x6e/0x9c
[<00000000000a6a44>] vfs_read+0x78/0x100
[<00000000000a6ba8>] sys_read+0x40/0x80
[<00000000000234a8>] sysc_do_restart+0x1a/0x1e
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
When 31 bit user space programs call sigaltstack on a 64 bit Linux
OS, the system call returns -1 with errno=EFAULT. The 31 bit pointer passed
to the system call is extended to 64 bit, but the high order bits are not
set to zero. The kernel detects the invalid user space pointer and
returns -EFAULT. To solve the problem, sys32_sigaltstack_wrapper()
instead of sys32_sigaltstack() has to be called. The wrapper function sets
the high order bits to zero.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Use the personality() macro to mask out all bits that are not
relevant for the personality type.
The personality field contains bits for other things as well,
so without masking out the not relevalent bits the comparison
won't do what is expected.
Reported-by: Andreas Krebbel <krebbel@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Some revisions of the 92hd8xxx codec's not supporting port power
downs in which the using of it causes capture and also randomly
playback streams to not function at all. Thus by disabling it by
default and adding a option to enable it manually will fix all issue
on current and future revisions.
Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Port 0xe power mapping was incorrect set to 0x80 changed to the correct
value 0x40.
Signed-off-by: Matthew Ranostay <mranostay@embeddedalley.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fix this:
> It appears that in the upstream balloon driver,
> the call to HYPERVISOR_update_va_mapping is missing
> from decrease_reservation. I think as a result,
> the balloon driver is eating memory but not
> releasing it to Xen, thus rendering the balloon
> driver essentially useless. (Can be observed via xentop.)
Signed-off-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
