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If a seccomp filter program is installed, older static binaries and
distributions with older libc implementations (glibc 2.13 and earlier)
that rely on vsyscall use will be terminated regardless of the filter
program policy when executing time, gettimeofday, or getcpu. This is
only the case when vsyscall emulation is in use (vsyscall=emulate is the
default).
This patch emulates system call entry inside a vsyscall=emulate by
populating regs->ax and regs->orig_ax with the system call number prior
to calling into seccomp such that all seccomp-dependencies function
normally. Additionally, system call return behavior is emulated in line
with other vsyscall entrypoints for the trace/trap cases.
[ v2: fixed ip and sp on SECCOMP_RET_TRAP/TRACE (thanks to luto@mit.edu) ]
Reported-and-tested-by: Owen Kibel <qmewlo@gmail.com>
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fix:
[ 3190.059226] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 3190.062224] IP: [<ffffffffa02aac66>] mmu_page_zap_pte+0x10/0xa7 [kvm]
[ 3190.063760] PGD 104f50067 PUD 112bea067 PMD 0
[ 3190.065309] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 3190.066860] CPU 1
[ ...... ]
[ 3190.109629] Call Trace:
[ 3190.111342] [<ffffffffa02aada6>] kvm_mmu_prepare_zap_page+0xa9/0x1fc [kvm]
[ 3190.113091] [<ffffffffa02ab2f5>] mmu_shrink+0x11f/0x1f3 [kvm]
[ 3190.114844] [<ffffffffa02ab25d>] ? mmu_shrink+0x87/0x1f3 [kvm]
[ 3190.116598] [<ffffffff81150c9d>] ? prune_super+0x142/0x154
[ 3190.118333] [<ffffffff8110a4f4>] ? shrink_slab+0x39/0x31e
[ 3190.120043] [<ffffffff8110a687>] shrink_slab+0x1cc/0x31e
[ 3190.121718] [<ffffffff8110ca1d>] do_try_to_free_pages
This is caused by shrinking page from the empty mmu, although we have
checked n_used_mmu_pages, it is useless since the check is out of mmu-lock
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux
Pull ACPI & Power Management patches from Len Brown.
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
acpi_pad: fix power_saving thread deadlock
ACPI video: Still use ACPI backlight control if _DOS doesn't exist
ACPI, APEI, Avoid too much error reporting in runtime
ACPI: Add a quirk for "AMILO PRO V2030" to ignore the timer overriding
ACPI: Remove one board specific WARN when ignoring timer overriding
ACPI: Make acpi_skip_timer_override cover all source_irq==0 cases
ACPI, x86: fix Dell M6600 ACPI reboot regression via DMI
ACPI sysfs.c strlen fix
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'video-bugzilla-43168', 'bugzilla-40002' and 'bugfix-misc' into release
bug fixes
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, cpufeature: Remove stray %s, add -w to mkcapflags.pl
x86, cpufeature: Catch duplicate CPU feature strings
x86, cpufeature: Rename X86_FEATURE_DTS to X86_FEATURE_DTHERM
x86: Fix kernel-doc warnings
x86, compat: Use test_thread_flag(TIF_IA32) in compat signal delivery
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There was a stray %s left from testing, remove it.
Add -w to the #! line (which is parsed by Perl even if the Perl
interpreter is invoked explicitly on the command line) to catch these
kinds of errors in the future.
Reported-by: Jean Delvare <khali@linux-fr.org>
Link: http://lkml.kernel.org/r/20120626143246.0c9bf301@endymion.delvare
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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We had a case of duplicate CPU feature strings, a user space ABI
violation, for almost two years. Make it a build error so that
doesn't happen again.
Link: http://lkml.kernel.org/r/4FE34BCB.5050305@linux.intel.com
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Jean Delvare <khali@linux-fr.org>
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It makes sense to label "Digital Thermal Sensor" as "DTS", but
unfortunately the string "dts" was already used for "Debug Store", and
/proc/cpuinfo is a user space ABI.
Therefore, rename this to "dtherm".
This conflict went into mainline via the hwmon tree without any x86
maintainer ack, and without any kind of hint in the subject.
a4659053 x86/hwmon: fix initialization of coretemp
Reported-by: Jean Delvare <khali@linux-fr.org>
Link: http://lkml.kernel.org/r/4FE34BCB.5050305@linux.intel.com
Cc: Jan Beulich <JBeulich@suse.com>
Cc: <stable@vger.kernel.org> v2.6.36..v3.4
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and printk fixes from Greg Kroah-Hartman:
"Here are some fixes for 3.5-rc4 that resolve the kmsg problems that
people have reported showing up after the printk and kmsg changes went
into 3.5-rc1. There are also a smattering of other tiny fixes for the
extcon and hyper-v drivers that people have reported.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'driver-core-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
extcon: max8997: Add missing kfree for info->edev in max8997_muic_remove()
extcon: Set platform drvdata in gpio_extcon_probe() and fix irq leak
extcon: Fix wrong index in max8997_extcon_cable[]
kmsg - kmsg_dump() fix CONFIG_PRINTK=n compilation
printk: return -EINVAL if the message len is bigger than the buf size
printk: use mutex lock to stop syslog_seq from going wild
kmsg - kmsg_dump() use iterator to receive log buffer content
vme: change maintainer e-mail address
Extcon: Don't try to create duplicate link names
driver core: fixup reversed deferred probe order
printk: Fix alignment of buf causing crash on ARM EABI
Tools: hv: verify origin of netlink connector message
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In the x86 32bit PAE CONFIG_TRANSPARENT_HUGEPAGE=y case while holding the
mmap_sem for reading, cmpxchg8b cannot be used to read pmd contents under
Xen.
So instead of dealing only with "consistent" pmdvals in
pmd_none_or_trans_huge_or_clear_bad() (which would be conceptually
simpler) we let pmd_none_or_trans_huge_or_clear_bad() deal with pmdvals
where the low 32bit and high 32bit could be inconsistent (to avoid having
to use cmpxchg8b).
The only guarantee we get from pmd_read_atomic is that if the low part of
the pmd was found null, the high part will be null too (so the pmd will be
considered unstable). And if the low part of the pmd is found "stable"
later, then it means the whole pmd was read atomically (because after a
pmd is stable, neither MADV_DONTNEED nor page faults can alter it anymore,
and we read the high part after the low part).
In the 32bit PAE x86 case, it is enough to read the low part of the pmdval
atomically to declare the pmd as "stable" and that's true for THP and no
THP, furthermore in the THP case we also have a barrier() that will
prevent any inconsistent pmdvals to be cached by a later re-read of the
*pmd.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jonathan Nieder <jrnieder@gmail.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Petr Matousek <pmatouse@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com>
Tested-by: Andrew Jones <drjones@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Wanpeng Li <liwp.linux@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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git://git.linaro.org/people/mszyprowski/linux-dma-mapping
Pull DMA-mapping fixes from Marek Szyprowski:
"A set of minor fixes for dma-mapping code (ARM and x86) required for
Contiguous Memory Allocator (CMA) patches merged in v3.5-rc1."
* 'fixes-for-linus' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping:
x86: dma-mapping: fix broken allocation when dma_mask has been provided
ARM: dma-mapping: fix debug messages in dmabounce code
ARM: mm: fix type of the arm_dma_limit global variable
ARM: dma-mapping: Add missing static storage class specifier
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git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull five Xen bug-fixes from Konrad Rzeszutek Wilk:
- When booting as PVHVM we would try to use PV console - but would not validate
the parameters causing us to crash during restore b/c we re-use the wrong event
channel.
- When booting on machines with SR-IOV PCI bridge we didn't check for the bridge
and tried to use it.
- Under AMD machines would advertise the APERFMPERF resulting in needless amount
of MSRs from the guest.
- A global value (xen_released_pages) was not subtracted at bootup when pages
were added back in. This resulted in the balloon worker having the wrong
account of how many pages were truly released.
- Fix dead-lock when xen-blkfront is run in the same domain as xen-blkback.
* tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: mark local pages as FOREIGN in the m2p_override
xen/setup: filter APERFMPERF cpuid feature out
xen/balloon: Subtract from xen_released_pages the count that is populated.
xen/pci: Check for PCI bridge before using it.
xen/events: Add WARN_ON when quick lookup found invalid type.
xen/hvc: Check HVM_PARAM_CONSOLE_[EVTCHN|PFN] for correctness.
xen/hvc: Fix error cases around HVM_PARAM_CONSOLE_PFN
xen/hvc: Collapse error logic.
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/smp: Fix topology checks on AMD MCM CPUs
x86/mm: Fix some kernel-doc warnings
x86, um: Correct syscall table type attributes breaking gcc 4.8
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar.
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
watchdog: Quiet down the boot messages
perf/x86: Fix broken LBR fixup code
tracing: Have tracing_off() actually turn tracing off
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Provide an iterator to receive the log buffer content, and convert all
kmsg_dump() users to it.
The structured data in the kmsg buffer now contains binary data, which
should no longer be copied verbatim to the kmsg_dump() users.
The iterator should provide reliable access to the buffer data, and also
supports proper log line-aware chunking of data while iterating.
Signed-off-by: Kay Sievers <kay@vrfy.org>
Tested-by: Tony Luck <tony.luck@intel.com>
Reported-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Tested-by: Anton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Signal delivery compat path may not have the 'TS_COMPAT' flag (that
flag indicates how we entered the kernel). So use
test_thread_flag(TIF_IA32) instead of is_ia32_task(): one of the
functions of TIF_IA32 is just what kind of signal frame we want.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1339722435.3475.57.camel@sbsiddha-desk.sc.intel.com
Cc: stable@kernel.org # v3.4
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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When the frontend and the backend reside on the same domain, even if we
add pages to the m2p_override, these pages will never be returned by
mfn_to_pfn because the check "get_phys_to_machine(pfn) != mfn" will
always fail, so the pfn of the frontend will be returned instead
(resulting in a deadlock because the frontend pages are already locked).
INFO: task qemu-system-i38:1085 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
qemu-system-i38 D ffff8800cfc137c0 0 1085 1 0x00000000
ffff8800c47ed898 0000000000000282 ffff8800be4596b0 00000000000137c0
ffff8800c47edfd8 ffff8800c47ec010 00000000000137c0 00000000000137c0
ffff8800c47edfd8 00000000000137c0 ffffffff82213020 ffff8800be4596b0
Call Trace:
[<ffffffff81101ee0>] ? __lock_page+0x70/0x70
[<ffffffff81a0fdd9>] schedule+0x29/0x70
[<ffffffff81a0fe80>] io_schedule+0x60/0x80
[<ffffffff81101eee>] sleep_on_page+0xe/0x20
[<ffffffff81a0e1ca>] __wait_on_bit_lock+0x5a/0xc0
[<ffffffff81101ed7>] __lock_page+0x67/0x70
[<ffffffff8106f750>] ? autoremove_wake_function+0x40/0x40
[<ffffffff811867e6>] ? bio_add_page+0x36/0x40
[<ffffffff8110b692>] set_page_dirty_lock+0x52/0x60
[<ffffffff81186021>] bio_set_pages_dirty+0x51/0x70
[<ffffffff8118c6b4>] do_blockdev_direct_IO+0xb24/0xeb0
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff8118ca95>] __blockdev_direct_IO+0x55/0x60
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff811e91c8>] ext3_direct_IO+0xf8/0x390
[<ffffffff811e71a0>] ? ext3_get_blocks_handle+0xe00/0xe00
[<ffffffff81004b60>] ? xen_mc_flush+0xb0/0x1b0
[<ffffffff81104027>] generic_file_aio_read+0x737/0x780
[<ffffffff813bedeb>] ? gnttab_map_refs+0x15b/0x1e0
[<ffffffff811038f0>] ? find_get_pages+0x150/0x150
[<ffffffff8119736c>] aio_rw_vect_retry+0x7c/0x1d0
[<ffffffff811972f0>] ? lookup_ioctx+0x90/0x90
[<ffffffff81198856>] aio_run_iocb+0x66/0x1a0
[<ffffffff811998b8>] do_io_submit+0x708/0xb90
[<ffffffff81199d50>] sys_io_submit+0x10/0x20
[<ffffffff81a18d69>] system_call_fastpath+0x16/0x1b
The explanation is in the comment within the code:
We need to do this because the pages shared by the frontend
(xen-blkfront) can be already locked (lock_page, called by
do_read_cache_page); when the userspace backend tries to use them
with direct_IO, mfn_to_pfn returns the pfn of the frontend, so
do_blockdev_direct_IO is going to try to lock the same pages
again resulting in a deadlock.
A simplified call graph looks like this:
pygrub QEMU
-----------------------------------------------
do_read_cache_page io_submit
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lock_page ext3_direct_IO
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bio_add_page
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lock_page
Internally the xen-blkback uses m2p_add_override to swizzle (temporarily)
a 'struct page' to have a different MFN (so that it can point to another
guest). It also can easily find out whether another pfn corresponding
to the mfn exists in the m2p, and can set the FOREIGN bit
in the p2m, making sure that mfn_to_pfn returns the pfn of the backend.
This allows the backend to perform direct_IO on these pages, but as a
side effect prevents the frontend from using get_user_pages_fast on
them while they are being shared with the backend.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Commit 0a2b9a6ea93 ("X86: integrate CMA with DMA-mapping subsystem")
broke memory allocation with dma_mask. This patch fixes possible kernel
ops caused by lack of resetting page variable when jumping to 'again' label.
Reported-by: Konrad Rzeszutek Wilk <konrad@darnok.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
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I noticed that the LBR fixups were not working anymore
on programs where they used to. I tracked this down to
a recent change to copy_from_user_nmi():
db0dc75d640 ("perf/x86: Check user address explicitly in copy_from_user_nmi()")
This commit added a call to __range_not_ok() to the
copy_from_user_nmi() routine. The problem is that the logic
of the test must be reversed. __range_not_ok() returns 0 if the
range is VALID. We want to return early from copy_from_user_nmi()
if the range is NOT valid.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Arun Sharma <asharma@fb.com>
Link: http://lkml.kernel.org/r/20120611134426.GA7542@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The warning below triggers on AMD MCM packages because physical package
IDs on the cores of a _physical_ socket are the same. I.e., this field
says which CPUs belong to the same physical package.
However, the same two CPUs belong to two different internal, i.e.
"logical" nodes in the same physical socket which is reflected in the
CPU-to-node map on x86 with NUMA.
Which makes this check wrong on the above topologies so circumvent it.
[ 0.444413] Booting Node 0, Processors #1 #2 #3 #4 #5 Ok.
[ 0.461388] ------------[ cut here ]------------
[ 0.465997] WARNING: at arch/x86/kernel/smpboot.c:310 topology_sane.clone.1+0x6e/0x81()
[ 0.473960] Hardware name: Dinar
[ 0.477170] sched: CPU #6's mc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency.
[ 0.486860] Booting Node 1, Processors #6
[ 0.491104] Modules linked in:
[ 0.494141] Pid: 0, comm: swapper/6 Not tainted 3.4.0+ #1
[ 0.499510] Call Trace:
[ 0.501946] [<ffffffff8144bf92>] ? topology_sane.clone.1+0x6e/0x81
[ 0.508185] [<ffffffff8102f1fc>] warn_slowpath_common+0x85/0x9d
[ 0.514163] [<ffffffff8102f2b7>] warn_slowpath_fmt+0x46/0x48
[ 0.519881] [<ffffffff8144bf92>] topology_sane.clone.1+0x6e/0x81
[ 0.525943] [<ffffffff8144c234>] set_cpu_sibling_map+0x251/0x371
[ 0.532004] [<ffffffff8144c4ee>] start_secondary+0x19a/0x218
[ 0.537729] ---[ end trace 4eaa2a86a8e2da22 ]---
[ 0.628197] #7 #8 #9 #10 #11 Ok.
[ 0.807108] Booting Node 3, Processors #12 #13 #14 #15 #16 #17 Ok.
[ 0.897587] Booting Node 2, Processors #18 #19 #20 #21 #22 #23 Ok.
[ 0.917443] Brought up 24 CPUs
We ran a topology sanity check test we have here on it and
it all looks ok... hopefully :).
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120529135442.GE29157@aftab.osrc.amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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CPU offline path calls the hrtimer interrupt handler with interrupts
disabled, without touching preempt_count, triggering this warning.
Remove the warning since it is supposed to be used from hrtimer
interrupt context only.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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This is the 2nd part of fix for kernel bugzilla 40002:
"IRQ 0 assigned to VGA"
https://bugzilla.kernel.org/show_bug.cgi?id=40002
The root cause is the buggy FW, whose ACPI tables assign the GSI 16
to 2 irqs 0 and 16(VGA), and the VGA is the right owner of GSI 16.
So add a quirk to ignore the irq0 overriding GSI 16 for the
FUJITSU SIEMENS AMILO PRO V2030 platform will solve this issue.
Reported-and-tested-by: Szymon Kowalczyk <fazerxlo@o2.pl>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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Current WARN msg is only for the ati_ixp4x0 board, while this function
is used by mulitple platforms. So this one board specific warning
is not appropriate any more.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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Currently when acpi_skip_timer_override is set, it only cover the
(source_irq == 0 && global_irq == 2) cases. While there is also
platform which need use this option and its global_irq is not 2.
This patch will extend acpi_skip_timer_override to cover all
timer overriding cases as long as the source irq is 0.
This is the first part of a fix to kernel bug bugzilla 40002:
"IRQ 0 assigned to VGA"
https://bugzilla.kernel.org/show_bug.cgi?id=40002
Reported-and-tested-by: Szymon Kowalczyk <fazerxlo@o2.pl>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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Pull crypto fixes from Herbert Xu:
"This push fixes an unaligned fault on x86-32 with aesni-intel and an
RNG failure with atmel-rng (repeated bits)."
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: aesni-intel - fix unaligned cbc decrypt for x86-32
hwrng: atmel-rng - fix race condition leading to repeated bits
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Fix kernel-doc warnings in arch/x86/mm/ioremap.c and
arch/x86/mm/pageattr.c, just like this one:
Warning(arch/x86/mm/ioremap.c:204):
No description found for parameter 'phys_addr'
Warning(arch/x86/mm/ioremap.c:204):
Excess function parameter 'offset' description in 'ioremap_nocache'
Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: Wanpeng Li <liwp.linux@gmail.com>
Link: http://lkml.kernel.org/r/1339296652-2935-1-git-send-email-liwp.linux@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The latest GCC 4.8 does some more checking on type attributes that
break the build for ARCH=um -> fill them in. Specifically, the
"asmlinkage" attributes is now tested for consistency.
Signed-off-by: Martin Pelikan <pelikan@storkhole.cz>
Link: http://lkml.kernel.org/r/1339269731-10772-1-git-send-email-pelikan@storkhole.cz
Acked-by: Richard Weinberger <richard@nod.at>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar.
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix the relax_domain_level boot parameter
sched: Validate assumptions in sched_init_numa()
sched: Always initialize cpu-power
sched: Fix domain iteration
sched/rt: Fix lockdep annotation within find_lock_lowest_rq()
sched/numa: Load balance between remote nodes
sched/x86: Calculate booted cores after construction of sibling_mask
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar.
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/nmi: Fix section mismatch warnings on 32-bit
x86/uv: Fix UV2 BAU legacy mode
x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space
x86, efi stub: Add .reloc section back into image
x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs
x86/reboot: Fix a warning message triggered by stop_other_cpus()
x86/intel/moorestown: Change intel_scu_devices_create() to __devinit
x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init()
x86/gart: Fix kmemleak warning
x86: mce: Add the dropped timer interval init back
x86/mce: Fix the MCE poll timer logic
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"A bit larger than what I'd wish for - half of it is due to hw driver
updates to Intel Ivy-Bridge which info got recently released,
cycles:pp should work there now too, amongst other things. (but we
are generally making exceptions for hardware enablement of this type.)
There are also callchain fixes in it - responding to mostly
theoretical (but valid) concerns. The tooling side sports perf.data
endianness/portability fixes which did not make it for the merge
window - and various other fixes as well."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
perf/x86: Check user address explicitly in copy_from_user_nmi()
perf/x86: Check if user fp is valid
perf: Limit callchains to 127
perf/x86: Allow multiple stacks
perf/x86: Update SNB PEBS constraints
perf/x86: Enable/Add IvyBridge hardware support
perf/x86: Implement cycles:p for SNB/IVB
perf/x86: Fix Intel shared extra MSR allocation
x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix
perf: Remove duplicate invocation on perf_event_for_each
perf uprobes: Remove unnecessary check before strlist__delete
perf symbols: Check for valid dso before creating map
perf evsel: Fix 32 bit values endianity swap for sample_id_all header
perf session: Handle endianity swap on sample_id_all header data
perf symbols: Handle different endians properly during symbol load
perf evlist: Pass third argument to ioctl explicitly
perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP
perf tools: Make --version show kernel version instead of pull req tag
perf tools: Check if callchain is corrupted
perf callchain: Make callchain cursors TLS
...
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It was reported that compiling for 32-bit caused a bunch of
section mismatch warnings:
VDSOSYM arch/x86/vdso/vdso32-syms.lds
LD arch/x86/vdso/built-in.o
LD arch/x86/built-in.o
WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in
reference from the variable test_nmi_ipi_callback_na.10451 to
the function .init.text:test_nmi_ipi_callback() [...]
WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in
reference from the variable nmi_unk_cb_na.10399 to the function
.init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399
references the function __init nmi_unk_cb() [...]
Both of these are attributed to the internal representation of
the nmiaction struct created during register_nmi_handler. The
reason for this is that those structs are not defined in the
init section whereas the rest of the code in nmi_selftest.c is.
To resolve this, I created a new #define,
register_nmi_handler_initonly, that tags the struct as
__initdata to resolve the mismatch. This #define should only be
used in rare situations where the register/unregister is called
during init of the kernel.
Big thanks to Jan Beulich for decoding this for me as I didn't
have a clue what was going on.
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for
tlb-shootdown (selective broadcast mode) always uses UV2
broadcast descriptor format. There is no need to clear the
'legacy' (UV1) mode, because the hardware always uses UV2 mode
for selective broadcast.
But the BIOS uses general broadcast and legacy mode, and the
hardware pays attention to the legacy mode bit for general
broadcast. So the kernel must not clear that mode bit.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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pre-allocation early page table space
Robin found this regression:
| I just tried to boot an 8TB system. It fails very early in boot with:
| Kernel panic - not syncing: Cannot find space for the kernel page tables
git bisect commit 722bc6b16771ed80871e1fd81c86d3627dda2ac8.
A git revert of that commit does boot past that point on the 8TB
configuration.
That commit will add up extra pages for all memory range even
above 4g.
Try to limit that extra page count adding to first entry only.
Bisected-by: Robin Holt <holt@sgi.com>
Tested-by: Robin Holt <holt@sgi.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CAE9FiQUj3wyzQxtq9yzBNc9u220p8JZ1FYHG7t%3DMOzJ%3D9BZMYA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
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Some UEFI firmware will not load a .efi with a .reloc section
with a size of 0.
Therefore, we create a .efi image with 4 main areas and 3 sections.
1. PE/COFF file header
2. .setup section (covers all setup code following the first sector)
3. .reloc section (contains 1 dummy reloc entry, created in build.c)
4. .text section (covers the remaining kernel image)
To make room for the new .setup section data, the header
bugger_off_msg had to be shortened.
Reported-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Link: http://lkml.kernel.org/r/1339085121-12760-1-git-send-email-jordan.l.justen@intel.com
Tested-by: Lee G Rosenbaum <lee.g.rosenbaum@intel.com>
Tested-by: Henrik Rydberg <rydberg@euromail.se>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
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Signed-off-by: Arun Sharma <asharma@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1334961696-19580-5-git-send-email-asharma@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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|
Signed-off-by: Arun Sharma <asharma@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1334961696-19580-4-git-send-email-asharma@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
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Without this patch, applications with two different stack
regions (eg: native stack vs JIT stack) get truncated
callchains even when RBP chaining is present. GDB shows proper
stack traces and the frame pointer chaining is intact.
This patch disables the (fp < RSP) check, hoping that other checks
in the code save the day for us. In our limited testing, this
didn't seem to break anything.
In the long term, we could potentially have userspace advise
the kernel on the range of valid stack addresses, so we don't
spend a lot of time unwinding from bogus addresses.
Signed-off-by: Arun Sharma <asharma@fb.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-perf-users@vger.kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1334961696-19580-2-git-send-email-asharma@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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|
Afaict there's no need to (incompletely) iterate the
MEM_UOPS_RETIRED.* umask state.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Implement rudimentary IVB perf support. The SDM states its identical
to SNB with exception of the exact event tables, but a quick look
suggests they're similar enough.
Also mark SNB-EP as broken for now.
Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Now that there's finally a chip with working PEBS (IvyBridge), we can
enable the hardware and implement cycles:p for SNB/IVB.
Cc: Stephane Eranian <eranian@google.com>
Requested-and-tested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338884803.28282.153.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
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Zheng Yan reported that event group validation can wreck event state
when Intel extra_reg allocation changes event state.
Validation shouldn't change any persistent state. Cloning events in
validate_{event,group}() isn't really pretty either, so add a few
special cases to avoid modifying the event state.
The code is restructured to minimize the special case impact.
Reported-by: Zheng Yan <zheng.z.yan@linux.intel.com>
Acked-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1338903031.28282.175.camel@twins
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
Commit 316ad248307fb ("sched/x86: Rewrite set_cpu_sibling_map()")
broke the booted_cores accounting.
The problem is that the booted_cores accounting needs all the
sibling links set up. So restore the second loop and add a comment as
to why its needed.
On qemu booted with -smp sockets=1,cores=2,threads=2;
Before:
$ grep cores /proc/cpuinfo
cpu cores : 2
cpu cores : 1
cpu cores : 4
cpu cores : 3
With the patch:
$ grep cores /proc/cpuinfo
cpu cores : 2
cpu cores : 2
cpu cores : 2
cpu cores : 2
Reported-by: Prarit Bhargava <prarit@redhat.com>
Reported-by: Borislav Petkov <bp@amd64.org>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120531073738.GH7511@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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|
In current Linux, percpu variable `vector_irq' is not cleared on
offlined cpus while disabling devices' irqs. If the cpu that has
the disabled irqs in vector_irq is hotplugged,
__setup_vector_irq() hits invalid irq vector and may crash.
This bug can be reproduced as following;
# echo 0 > /sys/devices/system/cpu/cpu7/online
# modprobe -r some_driver_using_interrupts # vector_irq@cpu7 uncleared
# echo 1 > /sys/devices/system/cpu/cpu7/online # kernel may crash
This patch fixes this bug by clearing vector_irq in
__clear_irq_vector() even if the cpu is offlined.
Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: ltc-kernel@ml.yrl.intra.hitachi.co.jp
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Alexander Gordeev <agordeev@redhat.com>
Link: http://lkml.kernel.org/r/4FC340BE.7080101@hitachi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
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When rebooting our 24 CPU Westmere servers with 3.4-rc6, we
always see this warning msg:
Restarting system.
machine restart
------------[ cut here ]------------
WARNING: at arch/x86/kernel/smp.c:125
native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN
Modules linked in: igb [last unloaded: scsi_wait_scan]
Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22
Call Trace:
<IRQ> [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96
[<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17
[<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7
[<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6
[<ffffffff81050112>] scheduler_tick+0xe0/0xe9
[<ffffffff81036768>] update_process_times+0x60/0x70
[<ffffffff81062f2f>] tick_sched_timer+0x68/0x92
[<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c
[<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0
[<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198
[<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94
[<ffffffff81655187>] apic_timer_interrupt+0x67/0x70
<EOI> [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4
[<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14
[<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6
[<ffffffff810188ba>] native_machine_shutdown+0x50/0x67
[<ffffffff81018926>] machine_shutdown+0xa/0xc
[<ffffffff8101897e>] native_machine_restart+0x20/0x32
[<ffffffff810189b0>] machine_restart+0xa/0xc
[<ffffffff8103b196>] kernel_restart+0x47/0x4c
[<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c
[<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12
[<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8
[<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7
[<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7
[<ffffffff816547a2>] system_call_fastpath+0x16/0x1b
---[ end trace 320af5cb1cb60c5b ]---
The root cause seems to be the
default_send_IPI_mask_allbutself_phys() takes quite some time (I
measured it could be several ms) to complete sending NMIs to all
the other 23 CPUs, and for HZ=250/1000 system, the time is long
enough for a timer interrupt to happen, which will in turn
trigger to kick load balance to a stopped CPU and cause this
warning in native_smp_send_reschedule().
So disabling the local irq before stop_other_cpu() can fix this
problem (tested 25 times reboot ok), and it is fine as there
should be nobody caring the timer interrupt in such reboot
stage.
The latest 3.4 kernel slightly changes this behavior by sending
REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR
fails, and this patch is still needed to prevent the problem.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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The allmodconfig hits:
WARNING: vmlinux.o(.text+0x6553d): Section mismatch in
reference from the function intel_scu_devices_create() to the
function .devinit.text: spi_register_board_info()
[...]
This patch marks intel_scu_devices_create() as devinit because
it only calls a devinit function, spi_register_board_info().
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Link: http://lkml.kernel.org/r/20120531212025.GA8519@breakpoint.cc
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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When hot-adding a CPU, the system outputs following messages
since node_to_cpumask_map[2] was not allocated memory.
Booting Node 2 Processor 32 APIC 0xc0
node_to_cpumask_map[2] NULL
Pid: 0, comm: swapper/32 Tainted: G A 3.3.5-acd #21
Call Trace:
[<ffffffff81048845>] debug_cpumask_set_cpu+0x155/0x160
[<ffffffff8105e28a>] ? add_timer_on+0xaa/0x120
[<ffffffff8150665f>] numa_add_cpu+0x1e/0x22
[<ffffffff815020bb>] identify_cpu+0x1df/0x1e4
[<ffffffff815020d6>] identify_econdary_cpu+0x16/0x1d
[<ffffffff81504614>] smp_store_cpu_info+0x3c/0x3e
[<ffffffff81505263>] smp_callin+0x139/0x1be
[<ffffffff815052fb>] start_secondary+0x13/0xeb
The reason is that the bit of node 2 was not set at
numa_nodes_parsed. numa_nodes_parsed is set by only
acpi_numa_processor_affinity_init /
acpi_numa_x2apic_affinity_init. Thus even if hot-added memory
which is same PXM as hot-added CPU is written in ACPI SRAT
Table, if the hot-added CPU is not written in ACPI SRAT table,
numa_nodes_parsed is not set.
But according to ACPI Spec Rev 5.0, it says about ACPI SRAT
table as follows: This optional table provides information that
allows OSPM to associate processors and memory ranges, including
ranges of memory provided by hot-added memory devices, with
system localities / proximity domains and clock domains.
It means that ACPI SRAT table only provides information for CPUs
present at boot time and for memory including hot-added memory.
So hot-added memory is written in ACPI SRAT table, but hot-added
CPU is not written in it. Thus numa_nodes_parsed should be set
by not only acpi_numa_processor_affinity_init /
acpi_numa_x2apic_affinity_init but also
acpi_numa_memory_affinity_init for the case.
Additionally, if system has cpuless memory node,
acpi_numa_processor_affinity_init /
acpi_numa_x2apic_affinity_init cannot set numa_nodes_parseds
since these functions cannot find cpu description for the node.
In this case, numa_nodes_parsed needs to be set by
acpi_numa_memory_affinity_init.
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: liuj97@gmail.com
Cc: kosaki.motohiro@gmail.com
Link: http://lkml.kernel.org/r/4FCC2098.4030007@jp.fujitsu.com
[ merged it ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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aperture_64.c now is using memblock, the previous
kmemleak_ignore() for alloc_bootmem() should be removed then.
Otherwise, with kmemleak enabled, kernel will throw warnings
like:
[ 0.000000] kmemleak: Trying to color unknown object at 0xffff8800c4000000 as Black
[ 0.000000] Pid: 0, comm: swapper/0 Not tainted 3.5.0-rc1-next-20120605+ #130
[ 0.000000] Call Trace:
[ 0.000000] [<ffffffff811b27e6>] paint_ptr+0x66/0xc0
[ 0.000000] [<ffffffff816b90fb>] kmemleak_ignore+0x2b/0x60
[ 0.000000] [<ffffffff81ef7bc0>] kmemleak_init+0x217/0x2c1
[ 0.000000] [<ffffffff81ed2b97>] start_kernel+0x32d/0x3eb
[ 0.000000] [<ffffffff81ed25e4>] ? repair_env_string+0x5a/0x5a
[ 0.000000] [<ffffffff81ed2356>] x86_64_start_reservations+0x131/0x135
[ 0.000000] [<ffffffff81ed2120>] ? early_idt_handlers+0x120/0x120
[ 0.000000] [<ffffffff81ed245c>] x86_64_start_kernel+0x102/0x111
[ 0.000000] kmemleak: Early log backtrace:
[ 0.000000] [<ffffffff816b911b>] kmemleak_ignore+0x4b/0x60
[ 0.000000] [<ffffffff81ee6a38>] gart_iommu_hole_init+0x3e7/0x547
[ 0.000000] [<ffffffff81edb20b>] pci_iommu_alloc+0x44/0x6f
[ 0.000000] [<ffffffff81ee81ad>] mem_init+0x19/0xec
[ 0.000000] [<ffffffff81ed2a54>] start_kernel+0x1ea/0x3eb
[ 0.000000] [<ffffffff81ed2356>] x86_64_start_reservations+0x131/0x135
[ 0.000000] [<ffffffff81ed245c>] x86_64_start_kernel+0x102/0x111
[ 0.000000] [<ffffffffffffffff>] 0xffffffffffffffff
Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
Cc: Xiaotian Feng <xtfeng@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1338922831-2847-1-git-send-email-xtfeng@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
|
commit 82f7af09 ("x86/mce: Cleanup timer mess) dropped the
initialization of the per cpu timer interval. Duh :(
Restore the previous behaviour.
Reported-by: Chen Gong <gong.chen@linux.intel.com>
Cc: bp@amd64.org
Cc: tony.luck@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|
|
Fix the x86 instruction decoder to decode bsr/bsf/jmpe with
operand-size prefix (66h). This fixes the test case failure
reported by Linus, attached below.
bsf/bsr/jmpe have a special encoding. Opcode map in
Intel Software Developers Manual vol2 says they have
TZCNT/LZCNT variants if it has F3h prefix. However, there
is no information if it has other 66h or F2h prefixes.
Current instruction decoder supposes that those are
bad instructions, but it actually accepts at least
operand-size prefixes.
H. Peter Anvin further explains:
" TZCNT/LZCNT are F3 + BSF/BSR exactly because the F2 and
F3 prefixes have historically been no-ops with most instructions.
This allows software to unconditionally use the prefixed versions
and get TZCNT/LZCNT on the processors that have them if they don't
care about the difference. "
This fixes errors reported by test_get_len:
Warning: arch/x86/tools/test_get_len found difference at <em_bsf>:ffffffff81036d87
Warning: ffffffff81036de5: 66 0f bc c2 bsf %dx,%ax
Warning: objdump says 4 bytes, but insn_get_length() says 3
Warning: arch/x86/tools/test_get_len found difference at <em_bsr>:ffffffff81036ea6
Warning: ffffffff81036f04: 66 0f bd c2 bsr %dx,%ax
Warning: objdump says 4 bytes, but insn_get_length() says 3
Warning: decoded and checked 13298882 instructions with 2 warnings
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <yrl.pp-manager.tt@hitachi.com>
Link: http://lkml.kernel.org/r/20120604150911.22338.43296.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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