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Pull kvm bugfixes from Marcelo Tosatti.
* git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: nVMX: Unconditionally uninit the MMU on nested vmexit
KVM: x86: Fix APIC map calculation after re-enabling
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Three reasons for doing this: 1. arch.walk_mmu points to arch.mmu anyway
in case nested EPT wasn't in use. 2. this aligns VMX with SVM. But 3. is
most important: nested_cpu_has_ept(vmcs12) queries the VMCS page, and if
one guest VCPU manipulates the page of another VCPU in L2, we may be
fooled to skip over the nested_ept_uninit_mmu_context, leaving mmu in
nested state. That can crash the host later on if nested_ept_get_cr3 is
invoked while L1 already left vmxon and nested.current_vmcs12 became
NULL therefore.
Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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Update arch.apic_base before triggering recalculate_apic_map. Otherwise
the recalculation will work against the previous state of the APIC and
will fail to build the correct map when an APIC is hardware-enabled
again.
This fixes a regression of 1e08ec4a13.
Cc: stable@vger.kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
"There is a small EFI fix and a big power regression fix in this batch.
My queue also had a fix for downing a CPU when there are insufficient
number of IRQ vectors available, but I'm holding that one for now due
to recent bug reports"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/efi: Don't select EFI from certain special ACPI drivers
x86 idle: Repair large-server 50-watt idle-power regression
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Linux 3.10 changed the timing of how thread_info->flags is touched:
x86: Use generic idle loop
(7d1a941731fabf27e5fb6edbebb79fe856edb4e5)
This caused Intel NHM-EX and WSM-EX servers to experience a large number
of immediate MONITOR/MWAIT break wakeups, which caused cpuidle to demote
from deep C-states to shallow C-states, which caused these platforms
to experience a significant increase in idle power.
Note that this issue was already present before the commit above,
however, it wasn't seen often enough to be noticed in power measurements.
Here we extend an errata workaround from the Core2 EX "Dunnington"
to extend to NHM-EX and WSM-EX, to prevent these immediate
returns from MWAIT, reducing idle power on these platforms.
While only acpi_idle ran on Dunnington, intel_idle
may also run on these two newer systems.
As of today, there are no other models that are known
to need this tweak.
Link: http://lkml.kernel.org/r/CAJvTdK=%2BaNN66mYpCGgbHGCHhYQAKx-vB0kJSWjVpsNb_hOAtQ@mail.gmail.com
Signed-off-by: Len Brown <len.brown@intel.com>
Link: http://lkml.kernel.org/r/baff264285f6e585df757d58b17788feabc68918.1387403066.git.len.brown@intel.com
Cc: <stable@vger.kernel.org> # 3.12.x, 3.11.x, 3.10.x
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.
The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.
During that time, a CPU may continue writing to the page.
This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.
When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.
This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).
The basic race looks like this:
CPU A CPU B CPU C
load TLB entry
make entry PTE/PMD_NUMA
fault on entry
read/write old page
start migrating page
change PTE/PMD to new page
read/write old page [*]
flush TLB
reload TLB from new entry
read/write new page
lose data
[*] the old page may belong to a new user at this point!
The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.
This should fix both NUMA migration and compaction.
[mgorman@suse.de: fix build]
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.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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Base pages are unmapped and flushed from cache and TLB during normal
page migration and replaced with a migration entry that causes any
parallel NUMA hinting fault or gup to block until migration completes.
THP does not unmap pages due to a lack of support for migration entries
at a PMD level. This allows races with get_user_pages and
get_user_pages_fast which commit 3f926ab945b6 ("mm: Close races between
THP migration and PMD numa clearing") made worse by introducing a
pmd_clear_flush().
This patch forces get_user_page (fast and normal) on a pmd_numa page to
go through the slow get_user_page path where it will serialise against
THP migration and properly account for the NUMA hinting fault. On the
migration side the page table lock is taken for each PTE update.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.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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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Three fixes for scheduler crashes, each triggers in relatively rare,
hardware environment dependent situations"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Rework sched_fair time accounting
math64: Add mul_u64_u32_shr()
sched: Remove PREEMPT_NEED_RESCHED from generic code
sched: Initialize power_orig for overlapping groups
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fix from Ingo Molnar:
"An x86/intel event constraint fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix constraint table end marker bug
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
"This is a pretty small batch:
The biggest single change is to stop using EFI time services on 32-bit
platforms. This matches our current behavior on 64-bit platforms as
we already had ruled them out there as being too unreliable. Turns
out that affects 32-bit platforms, too.
One NULL pointer fix for SGI UV.
Two minor build fixes, one of which only affects icc and the other
which affects icc and future versions or nonstandard default settings
of gcc"
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, efi: Don't use (U)EFI time services on 32 bit
x86, build, icc: Remove uninitialized_var() from compiler-intel.h
x86/UV: Fix NULL pointer dereference in uv_flush_tlb_others() if the 'nobau' boot option is used
x86, build: Pass in additional -mno-mmx, -mno-sse options
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Pull kvm fixes from Paolo Bonzini:
"Four security fixes for KVM on x86. Thanks to Andrew Honig and Lars
Bull from Google for reporting them"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: fix guest-initiated crash with x2apic (CVE-2013-6376)
KVM: x86: Convert vapic synchronization to _cached functions (CVE-2013-6368)
KVM: x86: Fix potential divide by 0 in lapic (CVE-2013-6367)
KVM: Improve create VCPU parameter (CVE-2013-4587)
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A guest can cause a BUG_ON() leading to a host kernel crash.
When the guest writes to the ICR to request an IPI, while in x2apic
mode the following things happen, the destination is read from
ICR2, which is a register that the guest can control.
kvm_irq_delivery_to_apic_fast uses the high 16 bits of ICR2 as the
cluster id. A BUG_ON is triggered, which is a protection against
accessing map->logical_map with an out-of-bounds access and manages
to avoid that anything really unsafe occurs.
The logic in the code is correct from real HW point of view. The problem
is that KVM supports only one cluster with ID 0 in clustered mode, but
the code that has the bug does not take this into account.
Reported-by: Lars Bull <larsbull@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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In kvm_lapic_sync_from_vapic and kvm_lapic_sync_to_vapic there is the
potential to corrupt kernel memory if userspace provides an address that
is at the end of a page. This patches concerts those functions to use
kvm_write_guest_cached and kvm_read_guest_cached. It also checks the
vapic_address specified by userspace during ioctl processing and returns
an error to userspace if the address is not a valid GPA.
This is generally not guest triggerable, because the required write is
done by firmware that runs before the guest. Also, it only affects AMD
processors and oldish Intel that do not have the FlexPriority feature
(unless you disable FlexPriority, of course; then newer processors are
also affected).
Fixes: b93463aa59d6 ('KVM: Accelerated apic support')
Reported-by: Andrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Under guest controllable circumstances apic_get_tmcct will execute a
divide by zero and cause a crash. If the guest cpuid support
tsc deadline timers and performs the following sequence of requests
the host will crash.
- Set the mode to periodic
- Set the TMICT to 0
- Set the mode bits to 11 (neither periodic, nor one shot, nor tsc deadline)
- Set the TMICT to non-zero.
Then the lapic_timer.period will be 0, but the TMICT will not be. If the
guest then reads from the TMCCT then the host will perform a divide by 0.
This patch ensures that if the lapic_timer.period is 0, then the division
does not occur.
Reported-by: Andrew Honig <ahonig@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Honig <ahonig@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Introduce mul_u64_u32_shr() as proposed by Andy a while back; it
allows using 64x64->128 muls on 64bit archs and recent GCC
which defines __SIZEOF_INT128__ and __int128.
(This new method will be used by the scheduler.)
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-hxjoeuzmrcaumR0uZwjpe2pv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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While hunting a preemption issue with Alexander, Ben noticed that the
currently generic PREEMPT_NEED_RESCHED stuff is horribly broken for
load-store architectures.
We currently rely on the IPI to fold TIF_NEED_RESCHED into
PREEMPT_NEED_RESCHED, but when this IPI lands while we already have
a load for the preempt-count but before the store, the store will erase
the PREEMPT_NEED_RESCHED change.
The current preempt-count only works on load-store archs because
interrupts are assumed to be completely balanced wrt their preempt_count
fiddling; the previous preempt_count load will match the preempt_count
state after the interrupt and therefore nothing gets lost.
This patch removes the PREEMPT_NEED_RESCHED usage from generic code and
pushes it into x86 arch code; the generic code goes back to relying on
TIF_NEED_RESCHED.
Boot tested on x86_64 and compile tested on ppc64.
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-and-Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20131128132641.GP10022@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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UEFI time services are often broken once we're in virtual mode. We were
already refusing to use them on 64-bit systems, but it turns out that
they're also broken on some 32-bit firmware, including the Dell Venue.
Disable them for now, we can revisit once we have the 1:1 mappings code
incorporated.
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
Link: http://lkml.kernel.org/r/1385754283-2464-1-git-send-email-matthew.garrett@nebula.com
Cc: <stable@vger.kernel.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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boot option is used
The SGI UV tlb shootdown code panics the system with a NULL
pointer deference if 'nobau' is specified on the boot
commandline.
uv_flush_tlb_other() gets called for every flush, whether the
BAU is disabled or not. It should not be keeping the s_enters
statistic while the BAU is disabled.
The panic occurs because during initialization
init_per_cpu_tunables() does not set the bcp->statp pointer if
'nobau' was specified.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: <stable@vger.kernel.org> # 3.12.x
Link: http://lkml.kernel.org/r/E1VnzBi-0005yF-MU@eag09.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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In checkin
5551a34e5aea x86-64, build: Always pass in -mno-sse
we unconditionally added -mno-sse to the main build, to keep newer
compilers from generating SSE instructions from autovectorization.
However, this did not extend to the special environments
(arch/x86/boot, arch/x86/boot/compressed, and arch/x86/realmode/rm).
Add -mno-sse to the compiler command line for these environments, and
add -mno-mmx to all the environments as well, as we don't want a
compiler to generate MMX code either.
This patch also removes a $(cc-option) call for -m32, since we have
long since stopped supporting compilers too old for the -m32 option,
and in fact hardcode it in other places in the Makefiles.
Reported-by: Kevin B. Smith <kevin.b.smith@intel.com>
Cc: Sunil K. Pandey <sunil.k.pandey@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/n/tip-j21wzqv790q834n7yc6g80j1@git.kernel.org
Cc: <stable@vger.kernel.org> # build fix only
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The EVENT_CONSTRAINT_END() macro defines the end marker as
a constraint with a weight of zero. This was all fine
until we blacklisted the corrupting memory events on
Intel IvyBridge. These events are blacklisted by using
a counter bitmask of zero. Thus, they also get a constraint
weight of zero.
The iteration macro: for_each_constraint tests the weight==0.
Therefore, it was stopping at the first blacklisted event, i.e.,
0xd0. The corrupting events were therefore considered as
unconstrained and were scheduled on any of the generic counters.
This patch fixes the end marker to have a weight of -1. With
this, the blacklisted events get an empty constraint and cannot
be scheduled which is what we want for now.
Signed-off-by: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: peterz@infradead.org
Cc: ak@linux.intel.com
Cc: jolsa@redhat.com
Cc: zheng.z.yan@intel.com
Link: http://lkml.kernel.org/r/20131204232437.GA10689@starlight
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 and EFI fixes from Peter Anvin:
"Half of these are EFI-related:
The by far biggest change is the change to hold off the deletion of a
sysfs entry while a backend scan is in progress. This is to avoid
calling kmemdup() while under a spinlock.
The other major change is for each entry in the EFI pstore backend to
get a unique identifier, as required by the pstore filesystem proper.
The other changes are:
A fix to the recent consolidation and optimization of using "asm goto"
with read-modify-write operation, which broke the bitops; specifically
in such a way that we could end up generating invalid code.
A build hack to make sure we compile with -mno-sse. icc, and most
likely future versions of gcc, can generate SSE instructions unless we
tell it not to.
A comment-only patch to a change the was due in part to an unpublished
erratum; now when the erratum is published we want to add a comment
explaining why"
* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic, doc: Justification for disabling IO APIC before Local APIC
x86, bitops: Correct the assembly constraints to testing bitops
x86-64, build: Always pass in -mno-sse
efi-pstore: Make efi-pstore return a unique id
x86/efi: Fix earlyprintk off-by-one bug
efivars, efi-pstore: Hold off deletion of sysfs entry until the scan is completed
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Since erratum AVR31 in "Intel Atom Processor C2000 Product Family
Specification Update" is now published, I added a justification
comment for disabling IO APIC before Local APIC, as changed in commit:
522e66464467 x86/apic: Disable I/O APIC before shutdown of the local APIC
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Link: http://lkml.kernel.org/r/1386202069-51515-1-git-send-email-fenghua.yu@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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In checkin:
0c44c2d0f459 x86: Use asm goto to implement better modify_and_test() functions
the various functions which do modify and test were unified and
optimized using "asm goto". However, this change missed the detail
that the bitops require an "Ir" constraint rather than an "er"
constraint ("I" = integer constant from 0-31, "e" = signed 32-bit
integer constant). This would cause code to miscompile if these
functions were used on constant bit positions 32-255 and the build to
fail if used on constant bit positions above 255.
Add the constraints as a parameter to the GEN_BINARY_RMWcc() macro to
avoid this problem.
Reported-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/529E8719.4070202@zytor.com
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Always pass in the -mno-sse argument, regardless if
-preferred-stack-boundary is supported. We never want to generate SSE
instructions in the kernel unless we *really* know what we're doing.
According to H. J. Lu, any version of gcc new enough that we support
it at all should handle the -mno-sse option, so just add it
unconditionally.
Reported-by: Kevin B. Smith <kevin.b.smith@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/n/tip-j21wzqv790q834n7yc6g80j1@git.kernel.org
Cc: <stable@vger.kernel.org> # build fix only
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Misc kernel and tooling fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools lib traceevent: Fix conversion of pointer to integer of different size
perf/trace: Properly use u64 to hold event_id
perf: Remove fragile swevent hlist optimization
ftrace, perf: Avoid infinite event generation loop
tools lib traceevent: Fix use of multiple options in processing field
perf header: Fix possible memory leaks in process_group_desc()
perf header: Fix bogus group name
perf tools: Tag thread comm as overriden
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Dave reported seeing the following incorrect output on his Thinkpad T420
when using earlyprintk=efi,
[ 0.000000] efi: EFI v2.00 by Lenovo
ACPI=0xdabfe000 ACPI 2.0=0xdabfe014 SMBIOS=0xdaa9e000
The output should be on one line, not split over two. The cause is an
off-by-one error when checking that the efi_y coordinate hasn't been
incremented out of bounds.
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
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Pull crypto update from Herbert Xu:
- Made x86 ablk_helper generic for ARM
- Phase out chainiv in favour of eseqiv (affects IPsec)
- Fixed aes-cbc IV corruption on s390
- Added constant-time crypto_memneq which replaces memcmp
- Fixed aes-ctr in omap-aes
- Added OMAP3 ROM RNG support
- Add PRNG support for MSM SoC's
- Add and use Job Ring API in caam
- Misc fixes
[ NOTE! This pull request was sent within the merge window, but Herbert
has some questionable email sending setup that makes him public enemy
#1 as far as gmail is concerned. So most of his emails seem to be
trapped by gmail as spam, resulting in me not seeing them. - Linus ]
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (49 commits)
crypto: s390 - Fix aes-cbc IV corruption
crypto: omap-aes - Fix CTR mode counter length
crypto: omap-sham - Add missing modalias
padata: make the sequence counter an atomic_t
crypto: caam - Modify the interface layers to use JR API's
crypto: caam - Add API's to allocate/free Job Rings
crypto: caam - Add Platform driver for Job Ring
hwrng: msm - Add PRNG support for MSM SoC's
ARM: DT: msm: Add Qualcomm's PRNG driver binding document
crypto: skcipher - Use eseqiv even on UP machines
crypto: talitos - Simplify key parsing
crypto: picoxcell - Simplify and harden key parsing
crypto: ixp4xx - Simplify and harden key parsing
crypto: authencesn - Simplify key parsing
crypto: authenc - Export key parsing helper function
crypto: mv_cesa: remove deprecated IRQF_DISABLED
hwrng: OMAP3 ROM Random Number Generator support
crypto: sha256_ssse3 - also test for BMI2
crypto: mv_cesa - Remove redundant of_match_ptr
crypto: sahara - Remove redundant of_match_ptr
...
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Pull DRM fixes from Dave Airlie:
"I was going to leave this until post -rc1 but sysfs fixes broke
hotplug in userspace, so I had to fix it harder, otherwise a set of
pulls from intel, radeon and vmware,
The vmware/ttm changes are bit larger but since its early and they are
unlikely to break anything else I put them in, it lets vmware work
with dri3"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (36 commits)
drm/sysfs: fix hotplug regression since lifetime changes
drm/exynos: g2d: fix memory leak to userptr
drm/i915: Fix gen3 self-refresh watermarks
drm/ttm: Remove set_need_resched from the ttm fault handler
drm/ttm: Don't move non-existing data
drm/radeon: hook up backlight functions for CI and KV family.
drm/i915: Replicate BIOS eDP bpp clamping hack for hsw
drm/i915: Do not enable package C8 on unsupported hardware
drm/i915: Hold pc8 lock around toggling pc8.gpu_idle
drm/i915: encoder->get_config is no longer optional
drm/i915/tv: add ->get_config callback
drm/radeon/cik: Add macrotile mode array query
drm/radeon/cik: Return backend map information to userspace
drm/vmwgfx: Make vmwgfx dma buffers prime aware
drm/vmwgfx: Make surfaces prime-aware
drm/vmwgfx: Hook up the prime ioctls
drm/ttm: Add a minimal prime implementation for ttm base objects
drm/vmwgfx: Fix false lockdep warning
drm/ttm: Allow execbuf util reserves without ticket
drm/i915: restore the early forcewake cleanup
...
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Pull KVM fixes from Gleb Natapov.
* 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: kvm_clear_guest_page(): fix empty_zero_page usage
kvm: mmu: delay mmu audit activation
arm/arm64: KVM: Fix hyp mappings of vmalloc regions
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There are two code paths how page with pmd page table can be freed:
pmd_free() and pmd_free_tlb().
I've missed the second one and didn't add page table destructor call
there. It leads to leak of page->ptl for pmd page tables, if
dynamically allocated page->ptl is in use.
The patch adds the missed destructor and modifies documentation
accordingly.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Andrey Vagin <avagin@openvz.org>
Tested-by: Andrey Vagin <avagin@openvz.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://people.freedesktop.org/~danvet/drm-intel into drm-fixes
Just a small pile of fixes for bugs and a few regressions. I'm still
trying to track down a driver load hang on my g33 (which infuriatingly
doesn't happen when loading the module manually after boot), somehow
bisecting loves to go astray on this one :( And there's a (harmless)
locking WARN in the suspend code due to one of Jesse's vlv backlight
rework patches. Otherwise nothing outstanding afaik.
* tag 'drm-intel-fixes-2013-11-20' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: Fix gen3 self-refresh watermarks
drm/i915: Replicate BIOS eDP bpp clamping hack for hsw
drm/i915: Do not enable package C8 on unsupported hardware
drm/i915: Hold pc8 lock around toggling pc8.gpu_idle
drm/i915: encoder->get_config is no longer optional
drm/i915/tv: add ->get_config callback
drm/i915: restore the early forcewake cleanup
Partially revert "drm/i915: tune the RC6 threshold for stability"
drm/i915: flush cursors harder
i915: Use 120MHz LVDS SSC clock for gen5/gen6/gen7
x86/early quirk: use gen6 stolen detection for VLV
drm/i915/dp: set sink to power down mode on dp disable
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Note that pmds[i] is simply uninitialized at that point...
Granted, it's very hard to hit (you need split page locks *and*
kmalloc(sizeof(spinlock_t), GFP_KERNEL) failing), but the code is
obviously bogus.
Introduced by commit 09ef4939850a ("x86: add missed
pgtable_pmd_page_ctor/dtor calls for preallocated pmds")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI and power management updates from Rafael Wysocki:
- ACPI-based device hotplug fixes for issues introduced recently and a
fix for an older error code path bug in the ACPI PCI host bridge
driver
- Fix for recently broken OMAP cpufreq build from Viresh Kumar
- Fix for a recent hibernation regression related to s2disk
- Fix for a locking-related regression in the ACPI EC driver from
Puneet Kumar
- System suspend error code path fix related to runtime PM and runtime
PM documentation update from Ulf Hansson
- cpufreq's conservative governor fix from Xiaoguang Chen
- New processor IDs for intel_idle and turbostat and removal of an
obsolete Kconfig option from Len Brown
- New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg
- Removal of several ACPI video DMI blacklist entries that are not
necessary any more from Aaron Lu
- Rework of the ACPI companion representation in struct device and code
cleanup related to that change from Rafael J Wysocki, Lan Tianyu and
Jarkko Nikula
- Fixes for assigning names to ACPI-enumerated I2C and SPI devices from
Jarkko Nikula
* tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (24 commits)
PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration
ACPI / scan: Set flags.match_driver in acpi_bus_scan_fixed()
ACPI / PCI root: Clear driver_data before failing enumeration
ACPI / hotplug: Fix PCI host bridge hot removal
ACPI / hotplug: Fix acpi_bus_get_device() return value check
cpufreq: governor: Remove fossil comment in the cpufreq_governor_dbs()
ACPI / video: clean up DMI table for initial black screen problem
ACPI / EC: Ensure lock is acquired before accessing ec struct members
PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()
ACPI / AC: Remove struct acpi_device pointer from struct acpi_ac
spi: Use stable dev_name for ACPI enumerated SPI slaves
i2c: Use stable dev_name for ACPI enumerated I2C slaves
ACPI: Provide acpi_dev_name accessor for struct acpi_device device name
ACPI / bind: Use (put|get)_device() on ACPI device objects too
ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro
ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
cpufreq: OMAP: Fix compilation error 'r & ret undeclared'
PM / Runtime: Fix error path for prepare
PM / Runtime: Update documentation around probe|remove|suspend
cpufreq: conservative: set requested_freq to policy max when it is over policy max
...
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We should not be using jump labels before they were initialized. Push back
the callback to until after jump label initialization.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
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Pull UML changes from Richard Weinberger:
"This pile contains a nice defconfig cleanup, a rewritten stack
unwinder and various cleanups"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Remove unused declarations from <as-layout.h>
um: remove used STDIO_CONSOLE Kconfig param
um/vdso: add .gitignore for a couple of targets
arch/um: make it work with defconfig and x86_64
um: Make kstack_depth_to_print conform to arch/x86
um: Get rid of thread_struct->saved_task
um: Make stack trace reliable against kernel mode faults
um: Rewrite show_stack()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Ingo Molnar:
"A modular build fix for certain .config's"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Export 'boot_cpu_physical_apicid' to modules
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq cleanups from Ingo Molnar:
"This is a multi-arch cleanup series from Thomas Gleixner, which we
kept to near the end of the merge window, to not interfere with
architecture updates.
This series (motivated by the -rt kernel) unifies more aspects of IRQ
handling and generalizes PREEMPT_ACTIVE"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
preempt: Make PREEMPT_ACTIVE generic
sparc: Use preempt_schedule_irq
ia64: Use preempt_schedule_irq
m32r: Use preempt_schedule_irq
hardirq: Make hardirq bits generic
m68k: Simplify low level interrupt handling code
genirq: Prevent spurious detection for unconditionally polled interrupts
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Vince's perf-trinity fuzzer found yet another 'interesting' problem.
When we sample the irq_work_exit tracepoint with period==1 (or
PERF_SAMPLE_PERIOD) and we add an fasync SIGNAL handler we create an
infinite event generation loop:
,-> <IPI>
| irq_work_exit() ->
| trace_irq_work_exit() ->
| ...
| __perf_event_overflow() -> (due to fasync)
| irq_work_queue() -> (irq_work_list must be empty)
'--------- arch_irq_work_raise()
Similar things can happen due to regular poll() wakeups if we exceed
the ring-buffer wakeup watermark, or have an event_limit.
To avoid this, dis-allow sampling this particular tracepoint.
In order to achieve this, create a special perf_perm function pointer
for each event and call this (when set) on trying to create a
tracepoint perf event.
[ roasted: use expr... to allow for ',' in your expression ]
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Dave Jones <davej@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20131114152304.GC5364@laptop.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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* pm-tools:
tools / power turbostat: Support Silvermont
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Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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arch/um/defconfig only lists one default configuration, and that applies
only to the i386 architecture. Replace it with two minimal
configuration files generated using `make savedefconfig`:
i386_defconfig and x86_64_defconfig
The build scripts now require two updates:
1. um's Kconfig (arch/x86/um/Kconfig) should specify an ARCH_DEFCONFIG
section explicitly pointing to these scripts if the required
variables are set. Take care to remove the DEFCONFIG_LIST section
defined in the included file arch/um/Kconfig.common.
2. um's Makefile (arch/um/Makefile) should set KBUILD_DEFCONFIG properly
for the top-level Makefile to pick up. Copy the logic in
arch/x86/Makefile to properly pick the defconfig file depending on
the actual architecture; except we're working with $SUBARCH here,
instead of $ARCH.
Now, you can do:
$ ARCH=um make defconfig
$ ARCH=um make
and successfully build User-Mode Linux on an x86_64 box in default
configuration.
Cc: Richard Weinberger <richard@nod.at>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
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Currently on UML stack traces are not very reliable and both
x86 and x86_64 have their on implementations.
This patch unifies both and adds support to outline unreliable
functions calls.
Signed-off-by: Richard Weinberger <richard@nod.at>
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing update from Steven Rostedt:
"This batch of changes is mostly clean ups and small bug fixes. The
only real feature that was added this release is from Namhyung Kim,
who introduced "set_graph_notrace" filter that lets you run the
function graph tracer and not trace particular functions and their
call chain.
Tom Zanussi added some updates to the ftrace multibuffer tracing that
made it more consistent with the top level tracing.
One of the fixes for perf function tracing required an API change in
RCU; the addition of "rcu_is_watching()". As Paul McKenney is pushing
that change in this release too, he gave me a branch that included all
the changes to get that working, and I pulled that into my tree in
order to complete the perf function tracing fix"
* tag 'trace-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Add rcu annotation for syscall trace descriptors
tracing: Do not use signed enums with unsigned long long in fgragh output
tracing: Remove unused function ftrace_off_permanent()
tracing: Do not assign filp->private_data to freed memory
tracing: Add helper function tracing_is_disabled()
tracing: Open tracer when ftrace_dump_on_oops is used
tracing: Add support for SOFT_DISABLE to syscall events
tracing: Make register/unregister_ftrace_command __init
tracing: Update event filters for multibuffer
recordmcount.pl: Add support for __fentry__
ftrace: Have control op function callback only trace when RCU is watching
rcu: Do not trace rcu_is_watching() functions
ftrace/x86: skip over the breakpoint for ftrace caller
trace/trace_stat: use rbtree postorder iteration helper instead of opencoding
ftrace: Add set_graph_notrace filter
ftrace: Narrow down the protected area of graph_lock
ftrace: Introduce struct ftrace_graph_data
ftrace: Get rid of ftrace_graph_filter_enabled
tracing: Fix potential out-of-bounds in trace_get_user()
tracing: Show more exact help information about snapshot
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git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial tree updates from Jiri Kosina:
"Usual earth-shaking, news-breaking, rocket science pile from
trivial.git"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
doc: add missing files to timers/00-INDEX
timekeeping: Fix some trivial typos in comments
mm: Fix some trivial typos in comments
irq: Fix some trivial typos in comments
NUMA: fix typos in Kconfig help text
mm: update 00-INDEX
doc: Documentation/DMA-attributes.txt fix typo
DRM: comment: `halve' -> `half'
Docs: Kconfig: `devlopers' -> `developers'
doc: typo on word accounting in kprobes.c in mutliple architectures
treewide: fix "usefull" typo
treewide: fix "distingush" typo
mm/Kconfig: Grammar s/an/a/
kexec: Typo s/the/then/
Documentation/kvm: Update cpuid documentation for steal time and pv eoi
treewide: Fix common typo in "identify"
__page_to_pfn: Fix typo in comment
Correct some typos for word frequency
clk: fixed-factor: Fix a trivial typo
...
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Pull Kconfig cleanups from Mark Salter:
"Remove some unused config options from C6X and clean up PC_PARPORT
dependencies. The latter was discussed here:
https://lkml.org/lkml/2013/10/8/12"
* tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming:
c6x: remove unused COMMON_CLKDEV Kconfig parameter
Kconfig cleanup (PARPORT_PC dependencies)
x86: select ARCH_MIGHT_HAVE_PC_PARPORT
unicore32: select ARCH_MIGHT_HAVE_PC_PARPORT
sparc: select ARCH_MIGHT_HAVE_PC_PARPORT
sh: select ARCH_MIGHT_HAVE_PC_PARPORT
powerpc: select ARCH_MIGHT_HAVE_PC_PARPORT
parisc: select ARCH_MIGHT_HAVE_PC_PARPORT
mips: select ARCH_MIGHT_HAVE_PC_PARPORT
microblaze: select ARCH_MIGHT_HAVE_PC_PARPORT
m68k: select ARCH_MIGHT_HAVE_PC_PARPORT
ia64: select ARCH_MIGHT_HAVE_PC_PARPORT
arm: select ARCH_MIGHT_HAVE_PC_PARPORT
alpha: select ARCH_MIGHT_HAVE_PC_PARPORT
c6x: remove unused parameter in Kconfig
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Commit 9ebddac7ea2a "ACPI, x86: Fix extended error log driver to depend on
CONFIG_X86_LOCAL_APIC" fixed a build error when CONFIG_X86_LOCAL_APIC was not
selected and !CONFIG_SMP.
However, since CONFIG_ACPI_EXTLOG is tristate, there is a second build error:
ERROR: "boot_cpu_physical_apicid" [drivers/acpi/acpi_extlog.ko] undefined!
The symbol needs to be exported for it to be available.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: Chen Gong <gong.chen@linux.intel.com>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1311141504080.30112@chino.kir.corp.google.com
[ Changed it to a _GPL() export. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Pull drm updates from Dave Airlie:
"This is a combo of -next and some -fixes that came in in the
intervening time.
Highlights:
New drivers:
ARM Armada driver for Marvell Armada 510 SOCs
Intel:
Broadwell initial support under a default off switch,
Stereo/3D HDMI mode support
Valleyview improvements
Displayport improvements
Haswell fixes
initial mipi dsi panel support
CRC support for debugging
build with CONFIG_FB=n
Radeon:
enable DPM on a number of GPUs by default
secondary GPU powerdown support
enable HDMI audio by default
Hawaii support
Nouveau:
dynamic pm code infrastructure reworked, does nothing major yet
GK208 modesetting support
MSI fixes, on by default again
PMPEG improvements
pageflipping fixes
GMA500:
minnowboard SDVO support
VMware:
misc fixes
MSM:
prime, plane and rendernodes support
Tegra:
rearchitected to put the drm driver into the drm subsystem.
HDMI and gr2d support for tegra 114 SoC
QXL:
oops fix, and multi-head fixes
DRM core:
sysfs lifetime fixes
client capability ioctl
further cleanups to device midlayer
more vblank timestamp fixes"
* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (789 commits)
drm/nouveau: do not map evicted vram buffers in nouveau_bo_vma_add
drm/nvc0-/gr: shift wrapping bug in nvc0_grctx_generate_r406800
drm/nouveau/pwr: fix missing mutex unlock in a failure path
drm/nv40/therm: fix slowing down fan when pstate undefined
drm/nv11-: synchronise flips to vblank, unless async flip requested
drm/nvc0-: remove nasty fifo swmthd hack for flip completion method
drm/nv10-: we no longer need to create nvsw object on user channels
drm/nouveau: always queue flips relative to kernel channel activity
drm/nouveau: there is no need to reserve/fence the new fb when flipping
drm/nouveau: when bailing out of a pushbuf ioctl, do not remove previous fence
drm/nouveau: allow nouveau_fence_ref() to be a noop
drm/nvc8/mc: msi rearm is via the nvc0 method
drm/ttm: Fix vma page_prot bit manipulation
drm/vmwgfx: Fix a couple of compile / sparse warnings and errors
drm/vmwgfx: Resource evict fixes
drm/edid: compare actual vrefresh for all modes for quirks
drm: shmob_drm: Convert to clk_prepare/unprepare
drm/nouveau: fix 32-bit build
drm/i915/opregion: fix build error on CONFIG_ACPI=n
Revert "drm/radeon/audio: don't set speaker allocation on DCE4+"
...
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Pull KVM changes from Paolo Bonzini:
"Here are the 3.13 KVM changes. There was a lot of work on the PPC
side: the HV and emulation flavors can now coexist in a single kernel
is probably the most interesting change from a user point of view.
On the x86 side there are nested virtualization improvements and a few
bugfixes.
ARM got transparent huge page support, improved overcommit, and
support for big endian guests.
Finally, there is a new interface to connect KVM with VFIO. This
helps with devices that use NoSnoop PCI transactions, letting the
driver in the guest execute WBINVD instructions. This includes some
nVidia cards on Windows, that fail to start without these patches and
the corresponding userspace changes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
kvm, vmx: Fix lazy FPU on nested guest
arm/arm64: KVM: PSCI: propagate caller endianness to the incoming vcpu
arm/arm64: KVM: MMIO support for BE guest
kvm, cpuid: Fix sparse warning
kvm: Delete prototype for non-existent function kvm_check_iopl
kvm: Delete prototype for non-existent function complete_pio
hung_task: add method to reset detector
pvclock: detect watchdog reset at pvclock read
kvm: optimize out smp_mb after srcu_read_unlock
srcu: API for barrier after srcu read unlock
KVM: remove vm mmap method
KVM: IOMMU: hva align mapping page size
KVM: x86: trace cpuid emulation when called from emulator
KVM: emulator: cleanup decode_register_operand() a bit
KVM: emulator: check rex prefix inside decode_register()
KVM: x86: fix emulation of "movzbl %bpl, %eax"
kvm_host: typo fix
KVM: x86: emulate SAHF instruction
MAINTAINERS: add tree for kvm.git
Documentation/kvm: add a 00-INDEX file
...
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git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull Xen updates from Konrad Rzeszutek Wilk:
"This has tons of fixes and two major features which are concentrated
around the Xen SWIOTLB library.
The short <blurb> is that the tracing facility (just one function) has
been added to SWIOTLB to make it easier to track I/O progress.
Additionally under Xen and ARM (32 & 64) the Xen-SWIOTLB driver
"is used to translate physical to machine and machine to physical
addresses of foreign[guest] pages for DMA operations" (Stefano) when
booting under hardware without proper IOMMU.
There are also bug-fixes, cleanups, compile warning fixes, etc.
The commit times for some of the commits is a bit fresh - that is b/c
we wanted to make sure we have the Ack's from the ARM folks - which
with the string of back-to-back conferences took a bit of time. Rest
assured - the code has been stewing in #linux-next for some time.
Features:
- SWIOTLB has tracing added when doing bounce buffer.
- Xen ARM/ARM64 can use Xen-SWIOTLB. This work allows Linux to
safely program real devices for DMA operations when running as a
guest on Xen on ARM, without IOMMU support. [*1]
- xen_raw_printk works with PVHVM guests if needed.
Bug-fixes:
- Make memory ballooning work under HVM with large MMIO region.
- Inform hypervisor of MCFG regions found in ACPI DSDT.
- Remove deprecated IRQF_DISABLED.
- Remove deprecated __cpuinit.
[*1]:
"On arm and arm64 all Xen guests, including dom0, run with second
stage translation enabled. As a consequence when dom0 programs a
device for a DMA operation is going to use (pseudo) physical
addresses instead machine addresses. This work introduces two trees
to track physical to machine and machine to physical mappings of
foreign pages. Local pages are assumed mapped 1:1 (physical address
== machine address). It enables the SWIOTLB-Xen driver on ARM and
ARM64, so that Linux can translate physical addresses to machine
addresses for dma operations when necessary. " (Stefano)"
* tag 'stable/for-linus-3.13-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (32 commits)
xen/arm: pfn_to_mfn and mfn_to_pfn return the argument if nothing is in the p2m
arm,arm64/include/asm/io.h: define struct bio_vec
swiotlb-xen: missing include dma-direction.h
pci-swiotlb-xen: call pci_request_acs only ifdef CONFIG_PCI
arm: make SWIOTLB available
xen: delete new instances of added __cpuinit
xen/balloon: Set balloon's initial state to number of existing RAM pages
xen/mcfg: Call PHYSDEVOP_pci_mmcfg_reserved for MCFG areas.
xen: remove deprecated IRQF_DISABLED
x86/xen: remove deprecated IRQF_DISABLED
swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
grant-table: call set_phys_to_machine after mapping grant refs
arm,arm64: do not always merge biovec if we are running on Xen
swiotlb: print a warning when the swiotlb is full
swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
tracing/events: Fix swiotlb tracepoint creation
swiotlb-xen: use xen_alloc/free_coherent_pages
xen: introduce xen_alloc/free_coherent_pages
...
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We've switched over every architecture that supports SMP to it, so
remove the new useless config variable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
Linus Torvalds
Jan Kiszka
Jan Kiszka
Len Brown
Rik van Riel
Mel Gorman
Gleb Natapov
Andy Honig
Peter Zijlstra
Matthew Garrett
cpw
H. Peter Anvin
Maria Dimakopoulou
Fenghua Yu
Matt Fleming
Kirill A. Shutemov
Dave Airlie
Al Viro
Sasha Levin
Rafael J. Wysocki
Ramkumar Ramachandra
Richard Weinberger
David Rientjes
Christoph Hellwig