- Fix KDB keyboard repeat scan codes and leaked keyboard events
- Fix kernel crash with kdb_printf() for users who compile new kdb_printf()'s
in early code
- Return all segment registers to gdb on x86_64
Features:
- KDB/KGDB hook the reboot notifier and end user can control if it stops,
detaches or does nothing (updated docs as well)
- Notify users who use CONFIG_DEBUG_RODATA to use hw breakpoints
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Merge tag 'for_linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb
Pull KGDB/KDB updates from Jason Wessel:
"Fixes:
- Fix KDB keyboard repeat scan codes and leaked keyboard events
- Fix kernel crash with kdb_printf() for users who compile new
kdb_printf()'s in early code
- Return all segment registers to gdb on x86_64
Features:
- KDB/KGDB hook the reboot notifier and end user can control if it
stops, detaches or does nothing (updated docs as well)
- Notify users who use CONFIG_DEBUG_RODATA to use hw breakpoints"
* tag 'for_linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
kdb: Add message about CONFIG_DEBUG_RODATA on failure to install breakpoint
kdb: Avoid using dbg_io_ops until it is initialized
kgdb,debug_core: add the ability to control the reboot notifier
KDB: Fix usability issues relating to the 'enter' key.
kgdb,debug-core,gdbstub: Hook the reboot notifier for debugger detach
kgdb: Respect that flush op is optional
kgdb: x86: Return all segment registers also in 64-bit mode
Pull crypto fixes from Herbert Xu:
"This fixes a build problem where two crypto modules both try to export
the same symbols (which shouldn't have been exported in the first
place)."
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: twofish-x86_64-3way - module init/exit functions should be static
crypto: camellia-x86_64 - module init/exit functions should be static
- PV multiconsole support, so that there can be hvc1, hvc2, etc;
- P-state and C-state power management driver that uploads said
power management data to the hypervisor. It also inhibits cpufreq
scaling drivers to load so that only the hypervisor can make power
management decisions - fixing a weird perf bug.
- Function Level Reset (FLR) support in the Xen PCI backend.
Fixes:
- Kconfig dependencies for Xen PV keyboard and video
- Compile warnings and constify fixes
- Change over to use percpu_xxx instead of this_cpu_xxx
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Merge tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull xen updates from Konrad Rzeszutek Wilk:
"which has three neat features:
- PV multiconsole support, so that there can be hvc1, hvc2, etc; This
can be used in HVM and in PV mode.
- P-state and C-state power management driver that uploads said power
management data to the hypervisor. It also inhibits cpufreq
scaling drivers to load so that only the hypervisor can make power
management decisions - fixing a weird perf bug.
There is one thing in the Kconfig that you won't like: "default y
if (X86_ACPI_CPUFREQ = y || X86_POWERNOW_K8 = y)" (note, that it
all depends on CONFIG_XEN which depends on CONFIG_PARAVIRT which by
default is off). I've a fix to convert that boolean expression
into "default m" which I am going to post after the cpufreq git
pull - as the two patches to make this work depend on a fix in Dave
Jones's tree.
- Function Level Reset (FLR) support in the Xen PCI backend.
Fixes:
- Kconfig dependencies for Xen PV keyboard and video
- Compile warnings and constify fixes
- Change over to use percpu_xxx instead of this_cpu_xxx"
Fix up trivial conflicts in drivers/tty/hvc/hvc_xen.c due to changes to
a removed commit.
* tag 'stable/for-linus-3.4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen kconfig: relax INPUT_XEN_KBDDEV_FRONTEND deps
xen/acpi-processor: C and P-state driver that uploads said data to hypervisor.
xen: constify all instances of "struct attribute_group"
xen/xenbus: ignore console/0
hvc_xen: introduce HVC_XEN_FRONTEND
hvc_xen: implement multiconsole support
hvc_xen: support PV on HVM consoles
xenbus: don't free other end details too early
xen/enlighten: Expose MWAIT and MWAIT_LEAF if hypervisor OKs it.
xen/setup/pm/acpi: Remove the call to boot_option_idle_override.
xenbus: address compiler warnings
xen: use this_cpu_xxx replace percpu_xxx funcs
xen/pciback: Support pci_reset_function, aka FLR or D3 support.
pci: Introduce __pci_reset_function_locked to be used when holding device_lock.
xen: Utilize the restore_msi_irqs hook.
Pull drm main changes from Dave Airlie:
"This is the main drm pull request, I'm probably going to send two more
smaller ones, will explain below.
This contains a patch that is also in the fbdev tree, but it should be
the same patch, it added an API for hot unplugging framebuffer
devices, and I need that API for a new driver.
It also contains some changes to the i2c tree which Jean has acked,
and one change to moorestown platform stuff in x86.
Highlights:
- new drivers: UDL driver for USB displaylink devices, kms only,
should support correct hotplug operations.
- core: i2c speedups + better hotplug support, EDID overriding via
firmware interface - allows user to load a firmware for a broken
monitor/kvm from userspace, it even has documentation for it.
- exynos: new HDMI audio + hdmi 1.4 + virtual output driver
- gma500: code cleanup
- radeon: cleanups, CS optimisations, streamout support and pageflip
fix
- nouveau: NVD9 displayport support + more reclocking work
- i915: re-enabling GMBUS, finish gpu patch (might help hibernation
who knows), missed irq fixes, stencil tiling fixes, interlaced
support, aliasesd PPGTT support for SNB/IVB, swizzling for SNB/IVB,
semaphore fixes
As well as the usual bunch of cleanups and fixes all over the place.
I've got two things I'd like to merge a bit later:
a) AMD support for all their new radeonhd 7000 series GPU and APUs.
AMD dropped this a bit late due to insane internal review
processes, (please AMD just follow Intel and let open source guys
ship stuff early) however I don't want to penalise people who own
this hardware (since its been on sale for 3-4 months and GPU hw
doesn't exactly have a lifetime in years) and consign them to
using closed drivers for longer than necessary. The changes are
well contained and just plug into the driver new gpu functionality
so they should be fairly regression proof. I just want to give
them a bit of a run on the hw AMD kindly sent me.
b) drm prime/dma-buf interface code. This is just infrastructure
code to expose the dma-buf stuff to drm drivers and to userspace.
I'm not planning on pushing any driver support in this cycle
(except maybe exynos), but I'd like to get the infrastructure code
in so for the next cycle I can start getting the driver support
into the individual drivers. We have started driver support for
i915, nouveau and udl along with I think exynos and omap in
staging. However this code relies on the dma-buf tree being
pulled into your tree first since it needs the latest interfaces
from that tree. I'll push to get that tree sent asap.
(oh and any warnings you see in i915 are gcc's fault from what anyone
can see)."
Fix up trivial conflicts in arch/x86/platform/mrst/mrst.c due to the new
msic_thermal_platform_data() thermal function being added next to the
tc35876x_platform_data() i2c device function..
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (326 commits)
drm/i915: use DDC_ADDR instead of hard-coding it
drm/radeon: use DDC_ADDR instead of hard-coding it
drm: remove unneeded redefinition of DDC_ADDR
drm/exynos: added virtual display driver.
drm: allow loading an EDID as firmware to override broken monitor
drm/exynos: enable hdmi audio feature
drm/exynos: add default pixel format for plane
drm/exynos: cleanup exynos_hdmi.h
drm/exynos: add is_local member in exynos_drm_subdrv struct
drm/exynos: add subdrv open/close functions
drm/exynos: remove module of exynos drm subdrv
drm/exynos: release pending pageflip events when closed
drm/exynos: added new funtion to get/put dma address.
drm/exynos: update gem and buffer framework.
drm/exynos: added mode_fixup feature and code clean.
drm/exynos: add HDMI version 1.4 support
drm/exynos: remove exynos_mixer.h
gma500: Fix mmap frambuffer
drm/radeon: Drop radeon_gem_object_(un)pin.
drm/radeon: Restrict offset for legacy display engine.
...
Even if the content is always 0, gdb expects us to return also ds,
es, fs, and gs while in x86-64 mode. Do this to avoid ugly errors on
"info registers".
[jason.wessel@windriver.com: adjust NUMREGBYTES for two new regs]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Pull x86 "urgent" leftovers from Ingo Molnar:
"Pending x86/urgent bits that were not high prio enough to warrant
-rc-less v3.3-final inclusion."
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, efi: Fix pointer math issue in handle_ramdisks()
x86/ioapic: Add register level checks to detect bogus io-apic entries
x86, mce: Fix rcu splat in drain_mce_log_buffer()
x86, memblock: Move mem_hole_size() to .init
Pull x86 platform changes from Ingo Molnar.
Removes the Moorestown platform that nobody ever used.
* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform: Move APIC ID validity check into platform APIC code
x86/olpc/xo15/sci: Enable lid close wakeup control
x86/geode/net5501: Add platform driver for Soekris Engineering net5501
x86/geode/alix2: Supplement driver to include GPIO button support
x86/mid/powerbtn: Use MSIC read/write instead of ipc_scu
x86/mid/thermal: Turn off thermistor
x86/mid/thermal: Add msic_thermal alias
x86/mid/thermal: Convert to use Intel MSIC API
x86/mid/scu_ipc: Remove Moorestown support
x86/mid: Kill off Moorestown
x86/mrst: Add msic_thermal platform support
x86/config: Select MSIC MFD driver on Intel Medfield platform
x86/mid: Remove Intel Moorestown
x86/mrst: Set ISA bus type for fake MP IRQs
x86/ioapic: Use legacy_pic to set correct gsi-irq mapping
Pull MCE changes from Ingo Molnar.
* 'x86-mce-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Fix return value of mce_chrdev_read() when erst is disabled
x86/mce: Convert static array of pointers to per-cpu variables
x86/mce: Replace hard coded hex constants with symbolic defines
x86/mce: Recognise machine check bank signature for data path error
x86/mce: Handle "action required" errors
x86/mce: Add mechanism to safely save information in MCE handler
x86/mce: Create helper function to save addr/misc when needed
HWPOISON: Add code to handle "action required" errors.
HWPOISON: Clean up memory_failure() vs. __memory_failure()
Pull x86/fpu changes from Ingo Molnar.
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
i387: Split up <asm/i387.h> into exported and internal interfaces
i387: Uninline the generic FP helpers that we expose to kernel modules
Pull trivial x86 branches from Ingo Molnar: small one-liners to fix up
details.
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Remove some noise from boot log when starting cpus
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, boot: Fix port argument to inl() function
* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, cpufeature: Add CPU features from Intel document 319433-012A
* 'x86-process-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86_64: Record stack pointer before task execution begins
* 'x86-uv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/UV: Lower UV rtc clocksource rating
Pull x86/asm changes from Ingo Molnar
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Include probe_roms.h in probe_roms.c
x86/32: Print control and debug registers for kerenel context
x86: Tighten dependencies of CPU_SUP_*_32
x86/numa: Improve internode cache alignment
x86: Fix the NMI nesting comments
x86-64: Improve insn scheduling in SAVE_ARGS_IRQ
x86-64: Fix CFI annotations for NMI nesting code
bitops: Add missing parentheses to new get_order macro
bitops: Optimise get_order()
bitops: Adjust the comment on get_order() to describe the size==0 case
x86/spinlocks: Eliminate TICKET_MASK
x86-64: Handle byte-wise tail copying in memcpy() without a loop
x86-64: Fix memcpy() to support sizes of 4Gb and above
x86-64: Fix memset() to support sizes of 4Gb and above
x86-64: Slightly shorten copy_page()
Merge first batch of patches from Andrew Morton:
"A few misc things and all the MM queue"
* emailed from Andrew Morton <akpm@linux-foundation.org>: (92 commits)
memcg: avoid THP split in task migration
thp: add HPAGE_PMD_* definitions for !CONFIG_TRANSPARENT_HUGEPAGE
memcg: clean up existing move charge code
mm/memcontrol.c: remove unnecessary 'break' in mem_cgroup_read()
mm/memcontrol.c: remove redundant BUG_ON() in mem_cgroup_usage_unregister_event()
mm/memcontrol.c: s/stealed/stolen/
memcg: fix performance of mem_cgroup_begin_update_page_stat()
memcg: remove PCG_FILE_MAPPED
memcg: use new logic for page stat accounting
memcg: remove PCG_MOVE_LOCK flag from page_cgroup
memcg: simplify move_account() check
memcg: remove EXPORT_SYMBOL(mem_cgroup_update_page_stat)
memcg: kill dead prev_priority stubs
memcg: remove PCG_CACHE page_cgroup flag
memcg: let css_get_next() rely upon rcu_read_lock()
cgroup: revert ss_id_lock to spinlock
idr: make idr_get_next() good for rcu_read_lock()
memcg: remove unnecessary thp check in page stat accounting
memcg: remove redundant returns
memcg: enum lru_list lru
...
This caused conflict with camellia-x86_64 when compiled into kernel, same
function names and not static.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This caused conflict with twofish-x86_64-3way when compiled into kernel,
same function names and not static.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Without this fix the cpumask_of_node() for a fake=numa=2 is:
cpumask 0 ff
cpumask 1 ff
with the fix it's correct and it's set to:
cpumask 0 55
cpumask 1 aa
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After looking up the vma which covers or follows the cached search
address, the following condition is always true:
!prev_vma || (addr >= prev_vma->vm_end)
so we can stop checking the previous VMA altogether.
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the required size is bigger than cached_hole_size it is better to
search from free_area_cache - it is easier to get a free region,
specifically for the 64 bit process whose address space is large enough
Do it just as hugetlb_get_unmapped_area_topdown() in arch/x86/mm/hugetlbpage.c
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Search again only if some holes may be skipped in the first pass.
[akpm@linux-foundation.org: clean up crazy compound definition]
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In some cases it may happen that pmd_none_or_clear_bad() is called with
the mmap_sem hold in read mode. In those cases the huge page faults can
allocate hugepmds under pmd_none_or_clear_bad() and that can trigger a
false positive from pmd_bad() that will not like to see a pmd
materializing as trans huge.
It's not khugepaged causing the problem, khugepaged holds the mmap_sem
in write mode (and all those sites must hold the mmap_sem in read mode
to prevent pagetables to go away from under them, during code review it
seems vm86 mode on 32bit kernels requires that too unless it's
restricted to 1 thread per process or UP builds). The race is only with
the huge pagefaults that can convert a pmd_none() into a
pmd_trans_huge().
Effectively all these pmd_none_or_clear_bad() sites running with
mmap_sem in read mode are somewhat speculative with the page faults, and
the result is always undefined when they run simultaneously. This is
probably why it wasn't common to run into this. For example if the
madvise(MADV_DONTNEED) runs zap_page_range() shortly before the page
fault, the hugepage will not be zapped, if the page fault runs first it
will be zapped.
Altering pmd_bad() not to error out if it finds hugepmds won't be enough
to fix this, because zap_pmd_range would then proceed to call
zap_pte_range (which would be incorrect if the pmd become a
pmd_trans_huge()).
The simplest way to fix this is to read the pmd in the local stack
(regardless of what we read, no need of actual CPU barriers, only
compiler barrier needed), and be sure it is not changing under the code
that computes its value. Even if the real pmd is changing under the
value we hold on the stack, we don't care. If we actually end up in
zap_pte_range it means the pmd was not none already and it was not huge,
and it can't become huge from under us (khugepaged locking explained
above).
All we need is to enforce that there is no way anymore that in a code
path like below, pmd_trans_huge can be false, but pmd_none_or_clear_bad
can run into a hugepmd. The overhead of a barrier() is just a compiler
tweak and should not be measurable (I only added it for THP builds). I
don't exclude different compiler versions may have prevented the race
too by caching the value of *pmd on the stack (that hasn't been
verified, but it wouldn't be impossible considering
pmd_none_or_clear_bad, pmd_bad, pmd_trans_huge, pmd_none are all inlines
and there's no external function called in between pmd_trans_huge and
pmd_none_or_clear_bad).
if (pmd_trans_huge(*pmd)) {
if (next-addr != HPAGE_PMD_SIZE) {
VM_BUG_ON(!rwsem_is_locked(&tlb->mm->mmap_sem));
split_huge_page_pmd(vma->vm_mm, pmd);
} else if (zap_huge_pmd(tlb, vma, pmd, addr))
continue;
/* fall through */
}
if (pmd_none_or_clear_bad(pmd))
Because this race condition could be exercised without special
privileges this was reported in CVE-2012-1179.
The race was identified and fully explained by Ulrich who debugged it.
I'm quoting his accurate explanation below, for reference.
====== start quote =======
mapcount 0 page_mapcount 1
kernel BUG at mm/huge_memory.c:1384!
At some point prior to the panic, a "bad pmd ..." message similar to the
following is logged on the console:
mm/memory.c:145: bad pmd ffff8800376e1f98(80000000314000e7).
The "bad pmd ..." message is logged by pmd_clear_bad() before it clears
the page's PMD table entry.
143 void pmd_clear_bad(pmd_t *pmd)
144 {
-> 145 pmd_ERROR(*pmd);
146 pmd_clear(pmd);
147 }
After the PMD table entry has been cleared, there is an inconsistency
between the actual number of PMD table entries that are mapping the page
and the page's map count (_mapcount field in struct page). When the page
is subsequently reclaimed, __split_huge_page() detects this inconsistency.
1381 if (mapcount != page_mapcount(page))
1382 printk(KERN_ERR "mapcount %d page_mapcount %d\n",
1383 mapcount, page_mapcount(page));
-> 1384 BUG_ON(mapcount != page_mapcount(page));
The root cause of the problem is a race of two threads in a multithreaded
process. Thread B incurs a page fault on a virtual address that has never
been accessed (PMD entry is zero) while Thread A is executing an madvise()
system call on a virtual address within the same 2 MB (huge page) range.
virtual address space
.---------------------.
| |
| |
.-|---------------------|
| | |
| | |<-- B(fault)
| | |
2 MB | |/////////////////////|-.
huge < |/////////////////////| > A(range)
page | |/////////////////////|-'
| | |
| | |
'-|---------------------|
| |
| |
'---------------------'
- Thread A is executing an madvise(..., MADV_DONTNEED) system call
on the virtual address range "A(range)" shown in the picture.
sys_madvise
// Acquire the semaphore in shared mode.
down_read(¤t->mm->mmap_sem)
...
madvise_vma
switch (behavior)
case MADV_DONTNEED:
madvise_dontneed
zap_page_range
unmap_vmas
unmap_page_range
zap_pud_range
zap_pmd_range
//
// Assume that this huge page has never been accessed.
// I.e. content of the PMD entry is zero (not mapped).
//
if (pmd_trans_huge(*pmd)) {
// We don't get here due to the above assumption.
}
//
// Assume that Thread B incurred a page fault and
.---------> // sneaks in here as shown below.
| //
| if (pmd_none_or_clear_bad(pmd))
| {
| if (unlikely(pmd_bad(*pmd)))
| pmd_clear_bad
| {
| pmd_ERROR
| // Log "bad pmd ..." message here.
| pmd_clear
| // Clear the page's PMD entry.
| // Thread B incremented the map count
| // in page_add_new_anon_rmap(), but
| // now the page is no longer mapped
| // by a PMD entry (-> inconsistency).
| }
| }
|
v
- Thread B is handling a page fault on virtual address "B(fault)" shown
in the picture.
...
do_page_fault
__do_page_fault
// Acquire the semaphore in shared mode.
down_read_trylock(&mm->mmap_sem)
...
handle_mm_fault
if (pmd_none(*pmd) && transparent_hugepage_enabled(vma))
// We get here due to the above assumption (PMD entry is zero).
do_huge_pmd_anonymous_page
alloc_hugepage_vma
// Allocate a new transparent huge page here.
...
__do_huge_pmd_anonymous_page
...
spin_lock(&mm->page_table_lock)
...
page_add_new_anon_rmap
// Here we increment the page's map count (starts at -1).
atomic_set(&page->_mapcount, 0)
set_pmd_at
// Here we set the page's PMD entry which will be cleared
// when Thread A calls pmd_clear_bad().
...
spin_unlock(&mm->page_table_lock)
The mmap_sem does not prevent the race because both threads are acquiring
it in shared mode (down_read). Thread B holds the page_table_lock while
the page's map count and PMD table entry are updated. However, Thread A
does not synchronize on that lock.
====== end quote =======
[akpm@linux-foundation.org: checkpatch fixes]
Reported-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Jones <davej@redhat.com>
Acked-by: Larry Woodman <lwoodman@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org> [2.6.38+]
Cc: Mark Salter <msalter@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs pile 1 from Al Viro:
"This is _not_ all; in particular, Miklos' and Jan's stuff is not there
yet."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
ext4: initialization of ext4_li_mtx needs to be done earlier
debugfs-related mode_t whack-a-mole
hfsplus: add an ioctl to bless files
hfsplus: change finder_info to u32
hfsplus: initialise userflags
qnx4: new helper - try_extent()
qnx4: get rid of qnx4_bread/qnx4_getblk
take removal of PF_FORKNOEXEC to flush_old_exec()
trim includes in inode.c
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
um: embed ->stub_pages[] into mmu_context
gadgetfs: list_for_each_safe() misuse
ocfs2: fix leaks on failure exits in module_init
ecryptfs: make register_filesystem() the last potential failure exit
ntfs: forgets to unregister sysctls on register_filesystem() failure
logfs: missing cleanup on register_filesystem() failure
jfs: mising cleanup on register_filesystem() failure
make configfs_pin_fs() return root dentry on success
configfs: configfs_create_dir() has parent dentry in dentry->d_parent
configfs: sanitize configfs_create()
...
This branch takes the PowerPC irq_host infrastructure (reverse mapping
from Linux IRQ numbers to hardware irq numbering), generalizes it,
renames it to irq_domain, and makes it available to all architectures.
Originally the plan has been to create an all-new irq_domain
implementation which addresses some of the powerpc shortcomings such
as not handling 1:1 mappings well, but doing that proved to be far
more difficult and invasive than generalizing the working code and
refactoring it in-place. So, this branch rips out the 'new'
irq_domain and replaces it with the modified powerpc version (in a
fully bisectable way of course). It converts all users over to the
new API and makes irq_domain selectable on any architecture.
No architecture is forced to enable irq_domain, but the infrastructure
is required for doing OpenFirmware style irq translations. It will
even work on SPARC even though SPARC has it's own mechanism for
translating irqs at boot time. MIPS, microblaze, embedded x86 and c6x
are converted too.
The resulting irq_domain code is probably still too verbose and can be
optimized more, but that can be done incrementally and is a task for
follow-on patches.
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Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6
Pull irq_domain support for all architectures from Grant Likely:
"Generialize powerpc's irq_host as irq_domain
This branch takes the PowerPC irq_host infrastructure (reverse mapping
from Linux IRQ numbers to hardware irq numbering), generalizes it,
renames it to irq_domain, and makes it available to all architectures.
Originally the plan has been to create an all-new irq_domain
implementation which addresses some of the powerpc shortcomings such
as not handling 1:1 mappings well, but doing that proved to be far
more difficult and invasive than generalizing the working code and
refactoring it in-place. So, this branch rips out the 'new'
irq_domain and replaces it with the modified powerpc version (in a
fully bisectable way of course). It converts all users over to the
new API and makes irq_domain selectable on any architecture.
No architecture is forced to enable irq_domain, but the infrastructure
is required for doing OpenFirmware style irq translations. It will
even work on SPARC even though SPARC has it's own mechanism for
translating irqs at boot time. MIPS, microblaze, embedded x86 and c6x
are converted too.
The resulting irq_domain code is probably still too verbose and can be
optimized more, but that can be done incrementally and is a task for
follow-on patches."
* tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: (31 commits)
dt: fix twl4030 for non-dt compile on x86
mfd: twl-core: Add IRQ_DOMAIN dependency
devicetree: Add empty of_platform_populate() for !CONFIG_OF_ADDRESS (sparc)
irq_domain: Centralize definition of irq_dispose_mapping()
irq_domain/mips: Allow irq_domain on MIPS
irq_domain/x86: Convert x86 (embedded) to use common irq_domain
ppc-6xx: fix build failure in flipper-pic.c and hlwd-pic.c
irq_domain/microblaze: Convert microblaze to use irq_domains
irq_domain/powerpc: Replace custom xlate functions with library functions
irq_domain/powerpc: constify irq_domain_ops
irq_domain/c6x: Use library of xlate functions
irq_domain/c6x: constify irq_domain structures
irq_domain/c6x: Convert c6x to use generic irq_domain support.
irq_domain: constify irq_domain_ops
irq_domain: Create common xlate functions that device drivers can use
irq_domain: Remove irq_domain_add_simple()
irq_domain: Remove 'new' irq_domain in favour of the ppc one
mfd: twl-core.c: Fix the number of interrupts managed by twl4030
of/address: add empty static inlines for !CONFIG_OF
irq_domain: Add support for base irq and hwirq in legacy mappings
...
Assorted extensions and fixes including:
* Introduction of early/late suspend/hibernation device callbacks.
* Generic PM domains extensions and fixes.
* devfreq updates from Axel Lin and MyungJoo Ham.
* Device PM QoS updates.
* Fixes of concurrency problems with wakeup sources.
* System suspend and hibernation fixes.
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Merge tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates for 3.4 from Rafael Wysocki:
"Assorted extensions and fixes including:
* Introduction of early/late suspend/hibernation device callbacks.
* Generic PM domains extensions and fixes.
* devfreq updates from Axel Lin and MyungJoo Ham.
* Device PM QoS updates.
* Fixes of concurrency problems with wakeup sources.
* System suspend and hibernation fixes."
* tag 'pm-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (43 commits)
PM / Domains: Check domain status during hibernation restore of devices
PM / devfreq: add relation of recommended frequency.
PM / shmobile: Make MTU2 driver use pm_genpd_dev_always_on()
PM / shmobile: Make CMT driver use pm_genpd_dev_always_on()
PM / shmobile: Make TMU driver use pm_genpd_dev_always_on()
PM / Domains: Introduce "always on" device flag
PM / Domains: Fix hibernation restore of devices, v2
PM / Domains: Fix handling of wakeup devices during system resume
sh_mmcif / PM: Use PM QoS latency constraint
tmio_mmc / PM: Use PM QoS latency constraint
PM / QoS: Make it possible to expose PM QoS latency constraints
PM / Sleep: JBD and JBD2 missing set_freezable()
PM / Domains: Fix include for PM_GENERIC_DOMAINS=n case
PM / Freezer: Remove references to TIF_FREEZE in comments
PM / Sleep: Add more wakeup source initialization routines
PM / Hibernate: Enable usermodehelpers in hibernate() error path
PM / Sleep: Make __pm_stay_awake() delete wakeup source timers
PM / Sleep: Fix race conditions related to wakeup source timer function
PM / Sleep: Fix possible infinite loop during wakeup source destruction
PM / Hibernate: print physical addresses consistently with other parts of kernel
...
Pull kmap_atomic cleanup from Cong Wang.
It's been in -next for a long time, and it gets rid of the (no longer
used) second argument to k[un]map_atomic().
Fix up a few trivial conflicts in various drivers, and do an "evil
merge" to catch some new uses that have come in since Cong's tree.
* 'kmap_atomic' of git://github.com/congwang/linux: (59 commits)
feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal
highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
drbd: remove the second argument of k[un]map_atomic()
zcache: remove the second argument of k[un]map_atomic()
gma500: remove the second argument of k[un]map_atomic()
dm: remove the second argument of k[un]map_atomic()
tomoyo: remove the second argument of k[un]map_atomic()
sunrpc: remove the second argument of k[un]map_atomic()
rds: remove the second argument of k[un]map_atomic()
net: remove the second argument of k[un]map_atomic()
mm: remove the second argument of k[un]map_atomic()
lib: remove the second argument of k[un]map_atomic()
power: remove the second argument of k[un]map_atomic()
kdb: remove the second argument of k[un]map_atomic()
udf: remove the second argument of k[un]map_atomic()
ubifs: remove the second argument of k[un]map_atomic()
squashfs: remove the second argument of k[un]map_atomic()
reiserfs: remove the second argument of k[un]map_atomic()
ocfs2: remove the second argument of k[un]map_atomic()
ntfs: remove the second argument of k[un]map_atomic()
...
Pull trivial tree from Jiri Kosina:
"It's indeed trivial -- mostly documentation updates and a bunch of
typo fixes from Masanari.
There are also several linux/version.h include removals from Jesper."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (101 commits)
kcore: fix spelling in read_kcore() comment
constify struct pci_dev * in obvious cases
Revert "char: Fix typo in viotape.c"
init: fix wording error in mm_init comment
usb: gadget: Kconfig: fix typo for 'different'
Revert "power, max8998: Include linux/module.h just once in drivers/power/max8998_charger.c"
writeback: fix fn name in writeback_inodes_sb_nr_if_idle() comment header
writeback: fix typo in the writeback_control comment
Documentation: Fix multiple typo in Documentation
tpm_tis: fix tis_lock with respect to RCU
Revert "media: Fix typo in mixer_drv.c and hdmi_drv.c"
Doc: Update numastat.txt
qla4xxx: Add missing spaces to error messages
compiler.h: Fix typo
security: struct security_operations kerneldoc fix
Documentation: broken URL in libata.tmpl
Documentation: broken URL in filesystems.tmpl
mtd: simplify return logic in do_map_probe()
mm: fix comment typo of truncate_inode_pages_range
power: bq27x00: Fix typos in comment
...
Pull networking merge from David Miller:
"1) Move ixgbe driver over to purely page based buffering on receive.
From Alexander Duyck.
2) Add receive packet steering support to e1000e, from Bruce Allan.
3) Convert TCP MD5 support over to RCU, from Eric Dumazet.
4) Reduce cpu usage in handling out-of-order TCP packets on modern
systems, also from Eric Dumazet.
5) Support the IP{,V6}_UNICAST_IF socket options, making the wine
folks happy, from Erich Hoover.
6) Support VLAN trunking from guests in hyperv driver, from Haiyang
Zhang.
7) Support byte-queue-limtis in r8169, from Igor Maravic.
8) Outline code intended for IP_RECVTOS in IP_PKTOPTIONS existed but
was never properly implemented, Jiri Benc fixed that.
9) 64-bit statistics support in r8169 and 8139too, from Junchang Wang.
10) Support kernel side dump filtering by ctmark in netfilter
ctnetlink, from Pablo Neira Ayuso.
11) Support byte-queue-limits in gianfar driver, from Paul Gortmaker.
12) Add new peek socket options to assist with socket migration, from
Pavel Emelyanov.
13) Add sch_plug packet scheduler whose queue is controlled by
userland daemons using explicit freeze and release commands. From
Shriram Rajagopalan.
14) Fix FCOE checksum offload handling on transmit, from Yi Zou."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1846 commits)
Fix pppol2tp getsockname()
Remove printk from rds_sendmsg
ipv6: fix incorrent ipv6 ipsec packet fragment
cpsw: Hook up default ndo_change_mtu.
net: qmi_wwan: fix build error due to cdc-wdm dependecy
netdev: driver: ethernet: Add TI CPSW driver
netdev: driver: ethernet: add cpsw address lookup engine support
phy: add am79c874 PHY support
mlx4_core: fix race on comm channel
bonding: send igmp report for its master
fs_enet: Add MPC5125 FEC support and PHY interface selection
net: bpf_jit: fix BPF_S_LDX_B_MSH compilation
net: update the usage of CHECKSUM_UNNECESSARY
fcoe: use CHECKSUM_UNNECESSARY instead of CHECKSUM_PARTIAL on tx
net: do not do gso for CHECKSUM_UNNECESSARY in netif_needs_gso
ixgbe: Fix issues with SR-IOV loopback when flow control is disabled
net/hyperv: Fix the code handling tx busy
ixgbe: fix namespace issues when FCoE/DCB is not enabled
rtlwifi: Remove unused ETH_ADDR_LEN defines
igbvf: Use ETH_ALEN
...
Fix up fairly trivial conflicts in drivers/isdn/gigaset/interface.c and
drivers/net/usb/{Kconfig,qmi_wwan.c} as per David.
Here's the big driver core merge for 3.4-rc1.
Lots of various things here, sysfs fixes/tweaks (with the nlink breakage
reverted), dynamic debugging updates, w1 drivers, hyperv driver updates,
and a variety of other bits and pieces, full information in the
shortlog.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core patches for 3.4-rc1 from Greg KH:
"Here's the big driver core merge for 3.4-rc1.
Lots of various things here, sysfs fixes/tweaks (with the nlink
breakage reverted), dynamic debugging updates, w1 drivers, hyperv
driver updates, and a variety of other bits and pieces, full
information in the shortlog."
* tag 'driver-core-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (78 commits)
Tools: hv: Support enumeration from all the pools
Tools: hv: Fully support the new KVP verbs in the user level daemon
Drivers: hv: Support the newly introduced KVP messages in the driver
Drivers: hv: Add new message types to enhance KVP
regulator: Support driver probe deferral
Revert "sysfs: Kill nlink counting."
uevent: send events in correct order according to seqnum (v3)
driver core: minor comment formatting cleanups
driver core: move the deferred probe pointer into the private area
drivercore: Add driver probe deferral mechanism
DS2781 Maxim Stand-Alone Fuel Gauge battery and w1 slave drivers
w1_bq27000: Only one thread can access the bq27000 at a time.
w1_bq27000 - remove w1_bq27000_write
w1_bq27000: remove unnecessary NULL test.
sysfs: Fix memory leak in sysfs_sd_setsecdata().
intel_idle: Revert change of auto_demotion_disable_flags for Nehalem
w1: Fix w1_bq27000
driver-core: documentation: fix up Greg's email address
powernow-k6: Really enable auto-loading
powernow-k7: Fix CPU family number
...
Pull timer changes for v3.4 from Ingo Molnar
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
ntp: Fix integer overflow when setting time
math: Introduce div64_long
cs5535-clockevt: Allow the MFGPT IRQ to be shared
cs5535-clockevt: Don't ignore MFGPT on SMP-capable kernels
x86/time: Eliminate unused irq0_irqs counter
clocksource: scx200_hrt: Fix the build
x86/tsc: Reduce the TSC sync check time for core-siblings
timer: Fix bad idle check on irq entry
nohz: Remove ts->Einidle checks before restarting the tick
nohz: Remove update_ts_time_stat from tick_nohz_start_idle
clockevents: Leave the broadcast device in shutdown mode when not needed
clocksource: Load the ACPI PM clocksource asynchronously
clocksource: scx200_hrt: Convert scx200 to use clocksource_register_hz
clocksource: Get rid of clocksource_calc_mult_shift()
clocksource: dbx500: convert to clocksource_register_hz()
clocksource: scx200_hrt: use pr_<level> instead of printk
time: Move common updates to a function
time: Reorder so the hot data is together
time: Remove most of xtime_lock usage in timekeeping.c
ntp: Add ntp_lock to replace xtime_locking
...
Pull scheduler changes for v3.4 from Ingo Molnar
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
printk: Make it compile with !CONFIG_PRINTK
sched/x86: Fix overflow in cyc2ns_offset
sched: Fix nohz load accounting -- again!
sched: Update yield() docs
printk/sched: Introduce special printk_sched() for those awkward moments
sched/nohz: Correctly initialize 'next_balance' in 'nohz' idle balancer
sched: Cleanup cpu_active madness
sched: Fix load-balance wreckage
sched: Clean up parameter passing of proc_sched_autogroup_set_nice()
sched: Ditch per cgroup task lists for load-balancing
sched: Rename load-balancing fields
sched: Move load-balancing arguments into helper struct
sched/rt: Do not submit new work when PI-blocked
sched/rt: Prevent idle task boosting
sched/wait: Add __wake_up_all_locked() API
sched/rt: Document scheduler related skip-resched-check sites
sched/rt: Use schedule_preempt_disabled()
sched/rt: Add schedule_preempt_disabled()
sched/rt: Do not throttle when PI boosting
sched/rt: Keep period timer ticking when rt throttling is active
...
Pull perf events changes for v3.4 from Ingo Molnar:
- New "hardware based branch profiling" feature both on the kernel and
the tooling side, on CPUs that support it. (modern x86 Intel CPUs
with the 'LBR' hardware feature currently.)
This new feature is basically a sophisticated 'magnifying glass' for
branch execution - something that is pretty difficult to extract from
regular, function histogram centric profiles.
The simplest mode is activated via 'perf record -b', and the result
looks like this in perf report:
$ perf record -b any_call,u -e cycles:u branchy
$ perf report -b --sort=symbol
52.34% [.] main [.] f1
24.04% [.] f1 [.] f3
23.60% [.] f1 [.] f2
0.01% [k] _IO_new_file_xsputn [k] _IO_file_overflow
0.01% [k] _IO_vfprintf_internal [k] _IO_new_file_xsputn
0.01% [k] _IO_vfprintf_internal [k] strchrnul
0.01% [k] __printf [k] _IO_vfprintf_internal
0.01% [k] main [k] __printf
This output shows from/to branch columns and shows the highest
percentage (from,to) jump combinations - i.e. the most likely taken
branches in the system. "branches" can also include function calls
and any other synchronous and asynchronous transitions of the
instruction pointer that are not 'next instruction' - such as system
calls, traps, interrupts, etc.
This feature comes with (hopefully intuitive) flat ascii and TUI
support in perf report.
- Various 'perf annotate' visual improvements for us assembly junkies.
It will now recognize function calls in the TUI and by hitting enter
you can follow the call (recursively) and back, amongst other
improvements.
- Multiple threads/processes recording support in perf record, perf
stat, perf top - which is activated via a comma-list of PIDs:
perf top -p 21483,21485
perf stat -p 21483,21485 -ddd
perf record -p 21483,21485
- Support for per UID views, via the --uid paramter to perf top, perf
report, etc. For example 'perf top --uid mingo' will only show the
tasks that I am running, excluding other users, root, etc.
- Jump label restructurings and improvements - this includes the
factoring out of the (hopefully much clearer) include/linux/static_key.h
generic facility:
struct static_key key = STATIC_KEY_INIT_FALSE;
...
if (static_key_false(&key))
do unlikely code
else
do likely code
...
static_key_slow_inc();
...
static_key_slow_inc();
...
The static_key_false() branch will be generated into the code with as
little impact to the likely code path as possible. the
static_key_slow_*() APIs flip the branch via live kernel code patching.
This facility can now be used more widely within the kernel to
micro-optimize hot branches whose likelihood matches the static-key
usage and fast/slow cost patterns.
- SW function tracer improvements: perf support and filtering support.
- Various hardenings of the perf.data ABI, to make older perf.data's
smoother on newer tool versions, to make new features integrate more
smoothly, to support cross-endian recording/analyzing workflows
better, etc.
- Restructuring of the kprobes code, the splitting out of 'optprobes',
and a corner case bugfix.
- Allow the tracing of kernel console output (printk).
- Improvements/fixes to user-space RDPMC support, allowing user-space
self-profiling code to extract PMU counts without performing any
system calls, while playing nice with the kernel side.
- 'perf bench' improvements
- ... and lots of internal restructurings, cleanups and fixes that made
these features possible. And, as usual this list is incomplete as
there were also lots of other improvements
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (120 commits)
perf report: Fix annotate double quit issue in branch view mode
perf report: Remove duplicate annotate choice in branch view mode
perf/x86: Prettify pmu config literals
perf report: Enable TUI in branch view mode
perf report: Auto-detect branch stack sampling mode
perf record: Add HEADER_BRANCH_STACK tag
perf record: Provide default branch stack sampling mode option
perf tools: Make perf able to read files from older ABIs
perf tools: Fix ABI compatibility bug in print_event_desc()
perf tools: Enable reading of perf.data files from different ABI rev
perf: Add ABI reference sizes
perf report: Add support for taken branch sampling
perf record: Add support for sampling taken branch
perf tools: Add code to support PERF_SAMPLE_BRANCH_STACK
x86/kprobes: Split out optprobe related code to kprobes-opt.c
x86/kprobes: Fix a bug which can modify kernel code permanently
x86/kprobes: Fix instruction recovery on optimized path
perf: Add callback to flush branch_stack on context switch
perf: Disable PERF_SAMPLE_BRANCH_* when not supported
perf/x86: Add LBR software filter support for Intel CPUs
...
Pull irq/core changes for v3.4 from Ingo Molnar
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Remove paranoid warnons and bogus fixups
genirq: Flush the irq thread on synchronization
genirq: Get rid of unnecessary IRQTF_DIED flag
genirq: No need to check IRQTF_DIED before stopping a thread handler
genirq: Get rid of unnecessary irqaction field in task_struct
genirq: Fix incorrect check for forced IRQ thread handler
softirq: Reduce invoke_softirq() code duplication
genirq: Fix long-term regression in genirq irq_set_irq_type() handling
x86-32/irq: Don't switch to irq stack for a user-mode irq
[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
* branch 'dcache-word-accesses':
vfs: use 'unsigned long' accesses for dcache name comparison and hashing
This does the name hashing and lookup using word-sized accesses when
that is efficient, namely on x86 (although any little-endian machine
with good unaligned accesses would do).
It does very much depend on little-endian logic, but it's a very hot
couple of functions under some real loads, and this patch improves the
performance of __d_lookup_rcu() and link_path_walk() by up to about 30%.
Giving a 10% improvement on some very pathname-heavy benchmarks.
Because we do make unaligned accesses past the filename, the
optimization is disabled when CONFIG_DEBUG_PAGEALLOC is active, and we
effectively depend on the fact that on x86 we don't really ever have the
last page of usable RAM followed immediately by any IO memory (due to
ACPI tables, BIOS buffer areas etc).
Some of the bit operations we do are a bit "subtle". It's commented,
but you do need to really think about the code. Or just consider it
black magic.
Thanks to people on G+ for some of the optimized bit tricks.
Matt Evans spotted that x86 bpf_jit was incorrectly handling negative
constant offsets in BPF_S_LDX_B_MSH instruction.
We need to abort JIT compilation like we do in common_load so that
filter uses the interpreter code and can call __load_pointer()
Reference: http://lists.openwall.net/netdev/2011/07/19/11
Thanks to Indan Zupancic to bring back this issue.
Reported-by: Matt Evans <matt@ozlabs.org>
Reported-by: Indan Zupancic <indan@nul.nu>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the following section warnings :
WARNING: vmlinux.o(.text+0x49dbc): Section mismatch in reference
from the function acpi_map_cpu2node() to the variable
.cpuinit.data:__apicid_to_node The function acpi_map_cpu2node()
references the variable __cpuinitdata __apicid_to_node. This is
often because acpi_map_cpu2node lacks a __cpuinitdata
annotation or the annotation of __apicid_to_node is wrong.
WARNING: vmlinux.o(.text+0x49dc1): Section mismatch in reference
from the function acpi_map_cpu2node() to the function
.cpuinit.text:numa_set_node() The function acpi_map_cpu2node()
references the function __cpuinit numa_set_node(). This is often
because acpi_map_cpu2node lacks a __cpuinit annotation or the
annotation of numa_set_node is wrong.
WARNING: vmlinux.o(.text+0x526e77): Section mismatch in
reference from the function prealloc_protection_domains() to the
function .init.text:alloc_passthrough_domain() The function
prealloc_protection_domains() references the function __init
alloc_passthrough_domain(). This is often because
prealloc_protection_domains lacks a __init annotation or the annotation of alloc_passthrough_domain is wrong.
Signed-off-by: Steffen Persvold <sp@numascale.com>
Link: http://lkml.kernel.org/r/1331810188-24785-1-git-send-email-sp@numascale.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
"filename" is a efi_char16_t string so this check for reaching the end
of the array doesn't work. We need to cast the pointer to (u8 *) before
doing the math.
This patch changes the "filename" to "filename_16" to avoid confusion in
the future.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: http://lkml.kernel.org/r/20120305180614.GA26880@elgon.mountain
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Move APIC ID validity check into platform APIC code, so it can
be overridden when needed. For NumaChip systems, always trust
MADT, as it's constructed with high APIC IDs.
Behaviour verifies on standard x86 systems and on NumaChip
systems with this, and compile-tested with allyesconfig.
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Reviewed-by: Steffen Persvold <sp@numascale.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1331709454-27966-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Merge tag 'v3.3-rc7' into x86/mce
Merge reason: Update from an ancient -rc1 base to an almost-final stable kernel.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
