noticed a bug in pci PAT code and memory type setting.
PCI mmap code did not set the proper protection in vma, when it
inherited protection in reserve_memtype. This bug only affects
the case where there exists a WC mapping before X does an mmap
with /proc or /sys pci interface. This will cause X userlevel
mmap from /proc or /sysfs to fail on fork.
Jeff Moyer [Thu, 19 Mar 2009 00:04:21 +0000 (17:04 -0700)]
aio: lookup_ioctx can return the wrong value when looking up a bogus context
The libaio test harness turned up a problem whereby lookup_ioctx on a
bogus io context was returning the 1 valid io context from the list
(harness/cases/3.p).
Because of that, an extra put_iocontext was done, and when the process
exited, it hit a BUG_ON in the put_iocontext macro called from exit_aio
(since we expect a users count of 1 and instead get 0).
Thanks to Zach for pointing out that hlist_for_each_entry_rcu will not
return with a NULL tpos at the end of the loop, even if the entry was
not found.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Acked-by: Zach Brown <zach.brown@oracle.com> Acked-by: Jens Axboe <jens.axboe@oracle.com> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Davide Libenzi [Thu, 19 Mar 2009 00:04:19 +0000 (17:04 -0700)]
eventfd: remove fput() call from possible IRQ context
Remove a source of fput() call from inside IRQ context. Myself, like Eric,
wasn't able to reproduce an fput() call from IRQ context, but Jeff said he was
able to, with the attached test program. Independently from this, the bug is
conceptually there, so we might be better off fixing it. This patch adds an
optimization similar to the one we already do on ->ki_filp, on ->ki_eventfd.
Playing with ->f_count directly is not pretty in general, but the alternative
here would be to add a brand new delayed fput() infrastructure, that I'm not
sure is worth it.
Signed-off-by: Davide Libenzi <davidel@xmailserver.org> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Cc: Zach Brown <zach.brown@oracle.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Thu, 19 Mar 2009 21:56:35 +0000 (14:56 -0700)]
Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
[S390] make page table upgrade work again
[S390] make page table walking more robust
[S390] Dont check for pfn_valid() in uaccess_pt.c
[S390] ftrace/mcount: fix kernel stack backchain
[S390] topology: define SD_MC_INIT to fix performance regression
[S390] __div64_31 broken for CONFIG_MARCH_G5
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: Clear space_info full when adding new devices
Btrfs: Fix locking around adding new space_info
Linus Torvalds [Thu, 19 Mar 2009 18:32:05 +0000 (11:32 -0700)]
Fix race in create_empty_buffers() vs __set_page_dirty_buffers()
Nick Piggin noticed this (very unlikely) race between setting a page
dirty and creating the buffers for it - we need to hold the mapping
private_lock until we've set the page dirty bit in order to make sure
that create_empty_buffers() might not build up a set of buffers without
the dirty bits set when the page is dirty.
I doubt anybody has ever hit this race (and it didn't solve the issue
Nick was looking at), but as Nick says: "Still, it does appear to solve
a real race, which we should close."
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
H. Peter Anvin [Wed, 18 Mar 2009 23:54:05 +0000 (16:54 -0700)]
x86, setup: fix the setting of 480-line VGA modes
Impact: fix rarely-used feature
The VGA Miscellaneous Output Register is read from address 0x3CC but
written to address 0x3C2. This was missed when this code was
converted from assembly to C. While we're at it, clean up the code by
making the overflow bits and the math used to set the bits explicit.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Linus Torvalds [Wed, 18 Mar 2009 14:39:11 +0000 (07:39 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: Fix vunmap and free order in snd_free_sgbuf_pages()
ALSA: mixart, fix lock imbalance
ALSA: pcm_oss, fix locking typo
ALSA: oss-mixer - Fixes recording gain control
ALSA: hda - Workaround for buggy DMA position on ATI controllers
ALSA: hda - Fix DMA mask for ATI controllers
ALSA: opl3sa2 - Fix NULL dereference when suspending snd_opl3sa2
After TASK_SIZE now gives the current size of the address space the
upgrade of a 64 bit process from 3 to 4 levels of page table needs
to use the arch_mmap_check hook to catch large mmap lengths. The
get_unmapped_area* functions need to check for -ENOMEM from the
arch_get_unmapped_area*, upgrade the page table and retry.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Make page table walking on s390 more robust. The current code requires
that the pgd/pud/pmd/pte loop is only done for address ranges that are
below the end address of the last vma of the address space. But this
is not always true, e.g. the generic page table walker does not guarantee
this. Change TASK_SIZE/TASK_SIZE_OF to reflect the current size of the
address space. This makes the generic page table walker happy but it
breaks the upgrade of a 3 level page table to a 4 level page table.
To make the upgrade work again another fix is required.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Gerald Schaefer [Wed, 18 Mar 2009 12:27:35 +0000 (13:27 +0100)]
[S390] Dont check for pfn_valid() in uaccess_pt.c
pfn_valid() actually checks for a valid struct page and not for a
valid pfn. Using xip mappings w/o struct pages, this will result in
-EFAULT returned by the (page table walk) user copy functions,
even though there is valid memory. Those user copy functions don't
need a struct page, so this patch just removes the pfn_valid() check.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Heiko Carstens [Wed, 18 Mar 2009 12:27:33 +0000 (13:27 +0100)]
[S390] topology: define SD_MC_INIT to fix performance regression
The default values for SD_MC_INIT cause an additional cpu usage of up
to 40% on some network benchmarks compared to the plain SD_CPU_INIT
values. So just define SD_MC_INIT to SD_CPU_INIT.
More tuning needs to be done.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The implementation of __div64_31 for G5 machines is broken. The comments
in __div64_31 are correct, only the code does not do what the comments
say. The part "If the remainder has overflown subtract base and increase
the quotient" is only partially realized, the base is subtracted correctly
but the quotient is only increased if the dividend had the last bit set.
Using the correct instruction fixes the problem.
Cc: stable@kernel.org Reported-by: Frans Pop <elendil@planet.nl> Tested-by: Frans Pop <elendil@planet.nl> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Rusty Russell [Tue, 17 Mar 2009 21:52:30 +0000 (08:22 +1030)]
x86, uv: fix cpumask iterator in uv_bau_init()
Impact: fix boot crash on UV systems
Commit 76ba0ecda0de9accea9a91cb6dbde46782110e1c "cpumask: use
cpumask_var_t in uv_flush_tlb_others" used cur_cpu as an iterator;
it was supposed to be zero for the code below it.
Suresh Siddha [Tue, 17 Mar 2009 18:16:54 +0000 (10:16 -0800)]
x86: add x2apic_wrmsr_fence() to x2apic flush tlb paths
Impact: optimize APIC IPI related barriers
Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barriers for xapic IPI paths.
x2apic MSR writes/reads don't have serializing semantics and hence need
a serializing instruction or mfence, to make all the previous memory
stores globally visisble before the x2apic msr write for IPI.
Add x2apic_wrmsr_fence() in flush tlb path to x2apic specific paths.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "steiner@sgi.com" <steiner@sgi.com> Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237313814.27006.203.camel@localhost.localdomain> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Takashi Iwai [Tue, 17 Mar 2009 13:00:06 +0000 (14:00 +0100)]
ALSA: Fix vunmap and free order in snd_free_sgbuf_pages()
In snd_free_sgbuf_pags(), vunmap() is called after releasing the SG
pages, and it causes errors on Xen as Xen manages the pages
differently. Although no significant errors have been reported on
the actual hardware, this order should be fixed other way round,
first vunmap() then free pages.
Cc: Jan Beulich <jbeulich@novell.com> Cc: <stable@kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Viral Mehta [Tue, 10 Mar 2009 14:43:18 +0000 (15:43 +0100)]
ALSA: oss-mixer - Fixes recording gain control
At the time of initialization, SNDRV_MIXER_OSS_PRESENT_PVOLUME bit is not
set for MIC (slot 7).
So, the same should not be checked when an application tries to do gain
control for audio recording devices.
Just check slot->present for SNDRV_MIXER_OSS_PRESENT_CVOLUME independently.
Verified with a simple application which opens /dev/dsp for recording and
/dev/mixer for volume control.
Takashi Iwai [Tue, 17 Mar 2009 06:49:14 +0000 (07:49 +0100)]
ALSA: hda - Workaround for buggy DMA position on ATI controllers
The position-buffer on ATI controllers are unreliable as well as
on VIA chips, thus the same workaround for DMA position reading as
VIA is useful for ATI.
Takashi Iwai [Tue, 17 Mar 2009 06:47:18 +0000 (07:47 +0100)]
ALSA: hda - Fix DMA mask for ATI controllers
ATI controllers (at least some SB0600 models) appear buggy to handle
64bit DMA. As a workaround, reset GCAP bit0 and let the driver to
use only 32bit DMA on these controllers.
Linus Torvalds [Wed, 18 Mar 2009 03:55:40 +0000 (20:55 -0700)]
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix bb_prealloc_list corruption due to wrong group locking
ext4: fix bogus BUG_ONs in in mballoc code
ext4: Print the find_group_flex() warning only once
ext4: fix header check in ext4_ext_search_right() for deep extent trees.
Suresh Siddha [Tue, 17 Mar 2009 00:05:05 +0000 (17:05 -0700)]
x86, dmar: use atomic allocations for QI and Intr-remapping init
Impact: invalid use of GFP_KERNEL in interrupt context
Queued invalidation and interrupt-remapping will get initialized with
interrupts disabled (while enabling interrupt-remapping). So use
GFP_ATOMIC instead of GFP_KERNEL for memory alloacations.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Suresh Siddha [Tue, 17 Mar 2009 00:05:04 +0000 (17:05 -0700)]
x86: fix broken irq migration logic while cleaning up multiple vectors
Impact: fix spurious IRQs
During irq migration, we send a low priority interrupt to the previous
irq destination. This happens in non interrupt-remapping case after interrupt
starts arriving at new destination and in interrupt-remapping case after
modifying and flushing the interrupt-remapping table entry caches.
This low priority irq cleanup handler can cleanup multiple vectors, as
multiple irq's can be migrated at almost the same time. While
there will be multiple invocations of irq cleanup handler (one cleanup
IPI for each irq migration), first invocation of the cleanup handler
can potentially cleanup more than one vector (as the first invocation can
see the requests for more than vector cleanup). When we cleanup multiple
vectors during the first invocation of the smp_irq_move_cleanup_interrupt(),
other vectors that are to be cleanedup can still be pending in the local
cpu's IRR (as smp_irq_move_cleanup_interrupt() runs with interrupts disabled).
When we are ready to unhook a vector corresponding to an irq, check if that
vector is registered in the local cpu's IRR. If so skip that cleanup and
do a self IPI with the cleanup vector, so that we give a chance to
service the pending vector interrupt and then cleanup that vector
allocation once we execute the lowest priority handler.
This fixes spurious interrupts seen when migrating multiple vectors
at the same time.
[ This is apparently possible even on conventional xapic, although to
the best of our knowledge it has never been seen. The stable
maintainers may wish to consider this one for -stable. ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: stable@kernel.org
Masami Hiramatsu [Mon, 16 Mar 2009 22:13:36 +0000 (18:13 -0400)]
module: fix refptr allocation and release order
Impact: fix ref-after-free crash on failed module load
Fix refptr bug: Change refptr allocation and release order not to access a module
data structure pointed by 'mod' after freeing mod->module_core.
This bug will cause kernel panic(e.g. failed to find undefined symbols).
This bug was reported on systemtap bugzilla.
http://sources.redhat.com/bugzilla/show_bug.cgi?id=9927
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Suresh Siddha [Tue, 17 Mar 2009 00:05:03 +0000 (17:05 -0700)]
x86, ioapic: Fix non atomic allocation with interrupts disabled
Impact: fix possible race
save_mask_IO_APIC_setup() was using non atomic memory allocation while getting
called with interrupts disabled. Fix this by splitting this into two different
function. Allocation part save_IO_APIC_setup() now happens before
disabling interrupts.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Suresh Siddha [Tue, 17 Mar 2009 00:05:01 +0000 (17:05 -0700)]
x86, x2apic: cleanup the IO-APIC level migration with interrupt-remapping
Impact: simplification
In the current code, for level triggered migration, we need to modify the
io-apic RTE with the update vector information, along with modifying interrupt
remapping table entry(IRTE) with vector and destination. This is to ensure that
remote IRR bit inthe IOAPIC RTE gets cleared when the cpu does EOI.
With this patch, for level triggered, we eliminate the io-apic RTE modification
(with the updated vector information), by using a virtual vector (io-apic pin
number). Real vector that is used for interrupting cpu will be coming from
the interrupt-remapping table entry. Trigger mode in the IRTE will always be
edge, and the actual level or edge trigger will be setup in the IO-APIC RTE.
So a level triggered interrupt will appear as an edge to the local apic
cpu but still as level to the IO-APIC.
With this change, level irq migration can be done by simply modifying
the interrupt-remapping table entry with out changing the io-apic RTE.
And as the interrupt appears as edge at the cpu, in addition to do the
local apic EOI, we need to do IO-APIC directed EOI to clear the remote
IRR bit in the IO-APIC RTE.
This simplies the irq migration in the presence of interrupt-remapping.
Idea-by: Rajesh Sankaran <rajesh.sankaran@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Suresh Siddha [Tue, 17 Mar 2009 00:04:59 +0000 (17:04 -0700)]
x86, x2apic: use virtual wire A mode in disable_IO_APIC() with interrupt-remapping
Impact: make kexec work with x2apic
disable_IO_APIC() gets called during crashdump aswell, which configures the
IO-APIC/LAPIC so that legacy interrupts can be delivered for the kexec'd kernel.
In the presence of interrupt-remapping, we need to change the
interrupt-remapping configuration aswell as modifying IO-APIC for virtual wire
B mode.
To keep things simple during the crash, use virtual wire A mode
(for which we don't need to touch io-apic and interrupt-remapping tables).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Suresh Siddha [Tue, 17 Mar 2009 00:04:57 +0000 (17:04 -0700)]
x86, dmar: start with sane state while enabling dma and interrupt-remapping
Impact: cleanup/sanitization
Start from a sane state while enabling dma and interrupt-remapping, by
clearing the previous recorded faults and disabling previously
enabled queued invalidation and interrupt-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Suresh Siddha [Tue, 17 Mar 2009 00:04:53 +0000 (17:04 -0700)]
x86, x2apic: fix lock ordering during IRQ migration
Impact: fix potential deadlock on x2apic
fix "hard-safe -> hard-unsafe lock order detected" with irq_2_ir_lock
On x2apic enabled system:
[ INFO: hard-safe -> hard-unsafe lock order detected ] 2.6.27-03151-g4480f15b #1
------------------------------------------------------
swapper/1 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
(irq_2_ir_lock){--..}, at: [<ffffffff8038ebc0>] get_irte+0x2f/0x95
and this task is already holding:
(&irq_desc_lock_class){+...}, at: [<ffffffff802649ed>] setup_irq+0x67/0x281
which would create a new lock dependency:
(&irq_desc_lock_class){+...} -> (irq_2_ir_lock){--..}
but this new dependency connects a hard-irq-safe lock:
(&irq_desc_lock_class){+...}
... which became hard-irq-safe at:
[<ffffffffffffffff>] 0xffffffffffffffff
H. Peter Anvin [Tue, 17 Mar 2009 22:26:06 +0000 (15:26 -0700)]
x86, setup: move 32-bit code to .text32
Impact: cleanup
The setup code is mostly 16-bit code, but there is a small stub of
32-bit code at the end. Move the 32-bit code to a separate segment,
.text32, to avoid scrambling the disassembly.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Thomas Bartosik [Mon, 16 Mar 2009 15:04:38 +0000 (16:04 +0100)]
USB: storage: Unusual USB device Prolific 2507 variation added
The "c-enter" USB to Toshiba 1.8" IDE enclosure needs special treatment
to work flawlessly. This patch is absolutely trivial, as the integrated
USB-IDE bridge is already identified to be an "unusual" device, only the
bcdDevice is different (lower) to the bcdDeviceMin already included in
the kernel.
It is a Prolific 2507 bridge.
Dirk Hohndel [Sun, 15 Mar 2009 03:47:39 +0000 (20:47 -0700)]
USB: Add Vendor/Product ID for new CDMA U727 to option driver
* newer versions of the Novatel Wireless U727 CDMA 3G USB stick
have a different Product ID (0x5010); adding this ID makes them
work just fine with the option driver
Signed-off-by: Moritz Muehlenhoff <jmm@debian.org> Tested-by: Jan Heitkoetter <devnull@heitkoetter.net> Cc: stable <stable@kernel.org> Signed-off-by: Phil Dibowitz <phil@ipom.com>
Dan Williams [Thu, 12 Mar 2009 10:53:00 +0000 (06:53 -0400)]
USB: Option: let cdc-acm handle Sony Ericsson F3507g / Dell 5530
The generic cdc-acm driver is now the best one to handle Sony Ericsson
F3507g-based devices (which the Dell 5530 is a rebrand of), now that all
the pieces are in place (ie, cac477e8f1038c41b6f29d3161ce351462ef3df7).
Removing the IDs from option allows cdc-acm to handle the device.
Signed-off-by: Dan Williams <dcbw@redhat.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Alan Stern [Mon, 16 Mar 2009 18:21:56 +0000 (14:21 -0400)]
USB: EHCI: expedite unlinks when the root hub is suspended
This patch (as1225) fixes a bug in ehci-hcd. The condition for
whether unlinked QHs can become IDLE should not be that the controller
is halted, but rather that the controller isn't running. In other
words when the root hub is suspended, the hardware doesn't own any
QHs.
This fixes a problem that can show up during hibernation: If a QH is
only partially unlinked when the root hub is frozen, then when the
root hub is thawed the QH won't be in the IDLE state. As a result it
can't be used properly for new URB submissions.
Karsten Wiese [Thu, 26 Feb 2009 00:47:48 +0000 (01:47 +0100)]
USB: EHCI: Fix isochronous URB leak
ehci-hcd uses usb_get_urb() and usb_put_urb() in an unbalanced way causing
isochronous URB's kref.counts incrementing once per usb_submit_urb() call.
The culprit is *usb being set to NULL when usb_put_urb() is called after URB
is given back.
Due to other fixes there is no need for ehci-hcd to deal with usb_get_urb()
nor usb_put_urb() anymore, so patch removes their usages in ehci-hcd.
Patch also makes ehci_to_hcd(ehci)->self.bandwidth_allocated adjust, if a
stream finishes.
Jan Dumon [Tue, 10 Mar 2009 16:29:47 +0000 (17:29 +0100)]
USB: unusual_devs: Add support for GI 0431 SD-Card interface
Enable the SD-Card interface on the GI 0431 HSUPA stick from Option.
The unusual_devs.h entry is necessary because the device descriptor is
vendor-specific. That prevents usb-storage from binding to it as an
interface driver.
Alan Stern [Mon, 9 Mar 2009 17:44:02 +0000 (13:44 -0400)]
USB: usbfs: keep async URBs until the device file is closed
The usbfs driver manages a list of completed asynchronous URBs. But
it is too eager to free the entries on this list: destroy_async() gets
called whenever an interface is unbound or a device is removed, and it
deallocates the outstanding struct async entries for all URBs on that
interface or device. This is wrong; the user program should be able
to reap an URB any time after it has completed, regardless of whether
or not the interface is still bound or the device is still present.
This patch (as1222) moves the code for deallocating the completed list
entries from destroy_async() to usbdev_release(). The outstanding
entries won't be freed until the user program has closed the device
file, thereby eliminating any possibility that the remaining URBs
might still be reaped.
This fixes a bug in which a program can hang in the USBDEVFS_REAPURB
ioctl when the device is unplugged.
Reported-and-tested-by: Martin Poupe <martin.poupe@upek.com> Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
x86/brk: put the brk reservations in their own section
Impact: disambiguate real .bss variables from .brk storage
Add a .brk section after the .bss section. This has no effect
on the final vmlinux, but it more clearly distinguishes the space
taken by actual .bss symbols, and the variable space reserved
by .brk users.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
x86/brk: make the brk reservation symbols inaccessible from C
Impact: bulletproofing, clarification
The brk reservation symbols are just there to document the amount
of space reserved by brk users in the final vmlinux file. Their
addresses are irrelevent, and using their addresses will cause
certain havok. Name them ".brk.NAME", which is a valid asm symbol
but C can't reference it; it also highlights their special
role in the symbol table.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
J. Bruce Fields [Mon, 16 Mar 2009 22:34:20 +0000 (18:34 -0400)]
nfsd: nfsd should drop CAP_MKNOD for non-root
Since creating a device node is normally an operation requiring special
privilege, Igor Zhbanov points out that it is surprising (to say the
least) that a client can, for example, create a device node on a
filesystem exported with root_squash.
So, make sure CAP_MKNOD is among the capabilities dropped when an nfsd
thread handles a request from a non-root user.
Reported-by: Igor Zhbanov <izh1979@gmail.com> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Benny Halevy [Wed, 4 Mar 2009 21:05:35 +0000 (23:05 +0200)]
NFSD: provide encode routine for OP_OPENATTR
Although this operation is unsupported by our implementation
we still need to provide an encode routine for it to
merely encode its (error) status back in the compound reply.
Thanks for Bill Baker at sun.com for testing with the Sun
OpenSolaris' client, finding, and reporting this bug at
Connectathon 2009.
This bug was introduced in 2.6.27
Signed-off-by: Benny Halevy <bhalevy@panasas.com> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
H. Peter Anvin [Tue, 17 Mar 2009 18:38:23 +0000 (11:38 -0700)]
x86-32: tighten the bound on additional memory to map
Impact: Tighten bound to avoid masking errors
The definition of MAPPING_BEYOND_END was excessive; this has a nasty
tendency to mask bugs. We have learned over time that this kind of
bug hiding can cause some very strange errors. Therefore, tighten the
bound to only need to map the actual kernel area.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Yinghai Lu <yinghai@kernel.org>
ALLOCATOR_SLOP is a vestigial remain from when we used the
bootmem allocator to allocate the kernel's linear memory mapping.
Now we directly reserve pages from the e820 mapping, and no
longer require secondary structures to keep track of allocated
pages.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86-32: make sure we map enough to fit linear map pagetables
Impact: crash fix
head_32.S needs to map the kernel itself, and enough space so
that mm/init.c can allocate space from the e820 allocator
for the linear map of low memory.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Linus Torvalds [Tue, 17 Mar 2009 17:02:35 +0000 (10:02 -0700)]
Avoid 64-bit "switch()" statements on 32-bit architectures
Commit ee6f779b9e0851e2f7da292a9f58e0095edf615a ("filp->f_pos not
correctly updated in proc_task_readdir") changed the proc code to use
filp->f_pos directly, rather than through a temporary variable. In the
process, that caused the operations to be done on the full 64 bits, even
though the offset is never that big.
That's all fine and dandy per se, but for some unfathomable reason gcc
generates absolutely horrid code when using 64-bit values in switch()
statements. To the point of actually calling out to gcc helper
functions like __cmpdi2 rather than just doing the trivial comparisons
directly the way gcc does for normal compares. At which point we get
link failures, because we really don't want to support that kind of
crazy code.
Fix this by just casting the f_pos value to "unsigned long", which
is plenty big enough for /proc, and avoids the gcc code generation issue.
Masami Hiramatsu [Mon, 16 Mar 2009 22:57:22 +0000 (18:57 -0400)]
prevent boosting kprobes on exception address
Don't boost at the addresses which are listed on exception tables,
because major page fault will occur on those addresses. In that case,
kprobes can not ensure that when instruction buffer can be freed since
some processes will sleep on the buffer.
Kumar Gala [Tue, 17 Mar 2009 15:17:50 +0000 (09:17 -0600)]
powerpc/mm: Respect _PAGE_COHERENT on classic ppc32 SW
Since we now set _PAGE_COHERENT in the Linux PTE we shouldn't be clearing
it out before we setup the SW TLB. Today all the SW TLB machines
(603/e300) that we support are non-SMP, however there are some errata on
some devices that cause us to set _PAGE_COHERENT via CPU_FTR_NEED_COHERENT.
Signed-off-by: Kumar Gala <galak@kernel.crashing.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Piotr Ziecik [Tue, 17 Mar 2009 15:17:50 +0000 (09:17 -0600)]
powerpc/5200: Enable CPU_FTR_NEED_COHERENT for MPC52xx
BestComm, a DMA engine in MPC52xx SoC, requires snooping when
CPU caches are enabled to work properly.
Adding CPU_FTR_NEED_COHERENT fixes NFS problems on MPC52xx machines
introduced by 'powerpc/mm: Fix handling of _PAGE_COHERENT in BAT setup
code' (sha1: 4c456a67f501b8b15542c7c21c28812bf88f484b).
Signed-off-by: Piotr Ziecik <kosmo@semihalf.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Linus Torvalds [Tue, 17 Mar 2009 15:13:17 +0000 (08:13 -0700)]
Fast TSC calibration: calculate proper frequency error bounds
In order for ntpd to correctly synchronize the clocks, the frequency of
the system clock must not be off by more than 500 ppm (or, put another
way, 1:2000), or ntpd will end up giving up on trying to synchronize
properly, and ends up reseting the clock in jumps instead.
The fast TSC PIT calibration sometimes failed this test - it was
assuming that the PIT reads always took about one microsecond each (2us
for the two reads to get a 16-bit timer), and that calibrating TSC to
the PIT over 15ms should thus be sufficient to get much closer than
500ppm (max 2us error on both sides giving 4us over 15ms: a 270 ppm
error value).
However, that assumption does not always hold: apparently some hardware
is either very much slower at reading the PIT registers, or there was
other noise causing at least one machine to get 700+ ppm errors.
So instead of using a fixed 15ms timing loop, this changes the fast PIT
calibration to read the TSC delta over the individual PIT timer reads,
and use the result to calculate the error bars on the PIT read timing
properly. We then successfully calibrate the TSC only if the maximum
error bars fall below 500ppm.
In the process, we also relax the timing to allow up to 25ms for the
calibration, although it can happen much faster depending on hardware.
Reported-and-tested-by: Jesper Krogh <jesper@krogh.cc> Cc: john stultz <johnstul@us.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Tue, 17 Mar 2009 14:58:26 +0000 (07:58 -0700)]
Fix potential fast PIT TSC calibration startup glitch
During bootup, when we reprogram the PIT (programmable interval timer)
to start counting down from 0xffff in order to use it for the fast TSC
calibration, we should also make sure to delay a bit afterwards to allow
the PIT hardware to actually start counting with the new value.
That will happens at the next CLK pulse (1.193182 MHz), so the easiest
way to do that is to just wait at least one microsecond after
programming the new PIT counter value. We do that by just reading the
counter value back once - which will take about 2us on PC hardware.
Reported-and-tested-by: john stultz <johnstul@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
so it's critical that we get the right group number back for
this prealloc context, to lock the right group (the one
associated with this pa) and prevent concurrent list manipulation.
however, ext4_mb_put_pa() passes in (pa->pa_pstart - 1) with a
comment, "-1 is to protect from crossing allocation group".
This makes sense for the group_pa, where pa_pstart is advanced
by the length which has been used (in ext4_mb_release_context()),
and when the entire length has been used, pa_pstart has been
advanced to the first block of the next group.
However, for inode_pa, pa_pstart is never advanced; it's just
set once to the first block in the group and not moved after
that. So in this case, if we subtract one in ext4_mb_put_pa(),
we are actually locking the *previous* group, and opening the
race with the other threads which do not subtract off the extra
block.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
x86, paravirt: prevent gcc from generating the wrong addressing mode
Impact: fix crash on VMI (VMware)
When we generate a call sequence for calling a paravirtualized
function, we presume that the generated code is "call *0xXXXXX",
which is a 6 byte opcode; this is larger than a normal
direct call, and so we can patch a direct call over it.
At the moment, however we give gcc enough rope to hang us by
putting the address in a register and generating a two byte
indirect-via-register call. Prevent this by explicitly
dereferencing the function pointer and passing it into the
asm as a constant.
This prevents crashes in VMI, as it cannot handle unpatchable
callsites.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Alok Kataria <akataria@vmware.com>
LKML-Reference: <49BEEDC2.2070809@goop.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Linus Torvalds [Mon, 16 Mar 2009 19:49:12 +0000 (12:49 -0700)]
Merge branch 'release' of 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-wmi: unsigned cannot be less than 0
thinkpad-acpi: fix module autoloading for older models
acer-wmi: Unmark as 'experimental'
acpi-wmi: Unmark as 'experimental'
acer-wmi: double free in acer_rfkill_exit()
platform/x86: depends instead of select for laptop platform drivers
asus-laptop: use select instead of depends on
eeepc-laptop: restore acpi_generate_proc_event()
asus-laptop: restore acpi_generate_proc_event()
acpi: check for pxm_to_node_map overflow
ACPI: remove doubled status checking
ACPI suspend: Blacklist Toshiba Satellite L300 that requires to set SCI_EN directly on resume
Revert "ACPI: make some IO ports off-limits to AML"
suspend: switch the Asus Pundit P1-AH2 to old ACPI sleep ordering
projects / linux-beck.git / log