Allow disabling the source id checking while programming the interrupt
remap table entry. Useful for debugging or working around the broken
source id checks on some platforms.
Signed-off-by: Chris Wright <chrisw@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Commit 69309a0590 ("x86, asm: Clean up and simplify set_64bit()")
sanitized the x86-64 types to set_64bit(), and incidentally resulted in
warnings like
drivers/pci/intr_remapping.c: In function 'modify_irte':
drivers/pci/intr_remapping.c:314: warning: passing argument 1 of 'set_64bit' from incompatible pointer type
arch/x86/include/asm/cmpxchg_64.h:6: note:expected 'volatile u64 *' but argument is of type 'long unsigned int *'
It turns out that the change to set_64bit() really does clean up things,
and the PCI intr_remapping.c file did a rather ugly cast in order to
avoid warnings with the previous set_64bit() type model.
Removing the ugly cast fixes the warning, and makes everybody happy and
expects a set_64bit() to take the logical "u64 *" argument.
Pointed-out-by: Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.infradead.org/iommu-2.6:
intel-iommu: Set a more specific taint flag for invalid BIOS DMAR tables
intel-iommu: Combine the BIOS DMAR table warning messages
panic: Add taint flag TAINT_FIRMWARE_WORKAROUND ('I')
panic: Allow warnings to set different taint flags
intel-iommu: intel_iommu_map_range failed at very end of address space
intel-iommu: errors with smaller iommu widths
intel-iommu: Fix boot inside 64bit virtualbox with io-apic disabled
intel-iommu: use physfn to search drhd for VF
intel-iommu: Print out iommu seq_id
intel-iommu: Don't complain that ACPI_DMAR_SCOPE_TYPE_IOAPIC is not supported
intel-iommu: Avoid global flushes with caching mode.
intel-iommu: Use correct domain ID when caching mode is enabled
intel-iommu mistakenly uses offset_pfn when caching mode is enabled
intel-iommu: use for_each_set_bit()
intel-iommu: Fix section mismatch dmar_ir_support() uses dmar_tbl.
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI/cardbus: Add a fixup hook and fix powerpc
PCI: change PCI nomenclature in drivers/pci/ (non-comment changes)
PCI: change PCI nomenclature in drivers/pci/ (comment changes)
PCI: fix section mismatch on update_res()
PCI: add Intel 82599 Virtual Function specific reset method
PCI: add Intel USB specific reset method
PCI: support device-specific reset methods
PCI: Handle case when no pci device can provide cache line size hint
PCI/PM: Propagate wake-up enable for PCIe devices too
vgaarbiter: fix a typo in the vgaarbiter Documentation
* git://git.infradead.org/iommu-2.6:
implement early_io{re,un}map for ia64
Revert "Intel IOMMU: Avoid memory allocation failures in dma map api calls"
intel-iommu: ignore page table validation in pass through mode
intel-iommu: Fix oops with intel_iommu=igfx_off
intel-iommu: Check for an RMRR which ends before it starts.
intel-iommu: Apply BIOS sanity checks for interrupt remapping too.
intel-iommu: Detect DMAR in hyperspace at probe time.
dmar: Fix build failure without NUMA, warn on bogus RHSA tables and don't abort
iommu: Allocate dma-remapping structures using numa locality info
intr_remap: Allocate intr-remapping table using numa locality info
dmar: Allocate queued invalidation structure using numa locality info
dmar: support for parsing Remapping Hardware Static Affinity structure
* 'timers-for-linus-hpet' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: hpet: Make WARN_ON understandable
x86: arch specific support for remapping HPET MSIs
intr-remap: generic support for remapping HPET MSIs
x86, hpet: Simplify the HPET code
x86, hpet: Disable per-cpu hpet timer if ARAT is supported
Change for PCI core to use pci_is_pcie() instead of checking
pci_dev->is_pcie.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Allocate intr-remapping table using numa locality info. On platforms
having remapping hardware units span different nodes, this enables
optimized intr-remapping table entry access by remapping hardware.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* git://git.infradead.org/iommu-2.6: (23 commits)
intel-iommu: Disable PMRs after we enable translation, not before
intel-iommu: Kill DMAR_BROKEN_GFX_WA option.
intel-iommu: Fix integer wrap on 32 bit kernels
intel-iommu: Fix integer overflow in dma_pte_{clear_range,free_pagetable}()
intel-iommu: Limit DOMAIN_MAX_PFN to fit in an 'unsigned long'
intel-iommu: Fix kernel hang if interrupt remapping disabled in BIOS
intel-iommu: Disallow interrupt remapping if not all ioapics covered
intel-iommu: include linux/dmi.h to use dmi_ routines
pci/dmar: correct off-by-one error in dmar_fault()
intel-iommu: Cope with yet another BIOS screwup causing crashes
intel-iommu: iommu init error path bug fixes
intel-iommu: Mark functions with __init
USB: Work around BIOS bugs by quiescing USB controllers earlier
ia64: IOMMU passthrough mode shouldn't trigger swiotlb init
intel-iommu: make domain_add_dev_info() call domain_context_mapping()
intel-iommu: Unify hardware and software passthrough support
intel-iommu: Cope with broken HP DC7900 BIOS
iommu=pt is a valid early param
intel-iommu: double kfree()
intel-iommu: Kill pointless intel_unmap_single() function
...
Fixed up trivial include lines conflict in drivers/pci/intel-iommu.c
BIOS clear DMAR table INTR_REMAP flag to disable interrupt remapping. Current
kernel only check interrupt remapping(IR) flag in DRHD's extended capability
register to decide interrupt remapping support or not. But IR flag will not
change when BIOS disable/enable interrupt remapping.
When user disable interrupt remapping in BIOS or BIOS often defaultly disable
interrupt remapping feature when BIOS is not mature.Though BIOS disable
interrupt remapping but intr_remapping_supported function will always report
to OS support interrupt remapping if VT-d2 chipset populated. On this
cases, kernel will continue enable interrupt remapping and result kernel panic.
This bug exist on almost all platforms with interrupt remapping support.
This patch add DMAR table INTR_REMAP flag check before enable interrupt
remapping.
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Current kernel enable interrupt remapping only when all the vt-d unit support
interrupt remapping. So it is reasonable we should also disallow enabling
intr-remapping if there any io-apics that are not listed under vt-d units.
Otherwise we can run into issues.
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
make it use the node from irq_desc.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A95C392.5050903@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Generic support for remapping HPET MSI's by parsing the HPET timer block
device scope in the ACPI DRHD tables. This is needed for platforms
supporting interrupt-remapping and MSI capable HPET timer block.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Jay Fenlason <fenlason@redhat.com>
LKML-Reference: <20090804190729.477649000@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
To support domain-isolation usages, the platform hardware must be
capable of uniquely identifying the requestor (source-id) for each
interrupt message. Without source-id checking for interrupt remapping
, a rouge guest/VM with assigned devices can launch interrupt attacks
to bring down anothe guest/VM or the VMM itself.
This patch adds source-id checking for interrupt remapping, and then
really isolates interrupts for guests/VMs with assigned devices.
Because PCI subsystem is not initialized yet when set up IOAPIC
entries, use read_pci_config_byte to access PCI config space directly.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Interrupt remapping table entry is 128bits. Currently, it only sets low
64bits of irte in modify_irte and free_irte. This ignores high 64bits
setting of irte, that means source-id setting will be ignored. This patch
sets the whole 128bits of irte when modify/free it. Following source-id
checking patch depends on this.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* git://git.infradead.org/~dwmw2/iommu-2.6.31:
intel-iommu: Fix one last ia64 build problem in Pass Through Support
VT-d: support the device IOTLB
VT-d: cleanup iommu_flush_iotlb_psi and flush_unmaps
VT-d: add device IOTLB invalidation support
VT-d: parse ATSR in DMA Remapping Reporting Structure
PCI: handle Virtual Function ATS enabling
PCI: support the ATS capability
intel-iommu: dmar_set_interrupt return error value
intel-iommu: Tidy up iommu->gcmd handling
intel-iommu: Fix tiny theoretical race in write-buffer flush.
intel-iommu: Clean up handling of "caching mode" vs. IOTLB flushing.
intel-iommu: Clean up handling of "caching mode" vs. context flushing.
VT-d: fix invalid domain id for KVM context flush
Fix !CONFIG_DMAR build failure introduced by Intel IOMMU Pass Through Support
Intel IOMMU Pass Through Support
Fix up trivial conflicts in drivers/pci/{intel-iommu.c,intr_remapping.c}
Conflicts:
arch/x86/kernel/apic/io_apic.c
Merge reason: non-trivial interaction between ongoing work in io_apic.c
and the NUMA migration feature in the irq tree.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This simplifies the node awareness of the code. All our allocators
only deal with a NUMA node ID locality not with CPU ids anyway - so
there's no need to maintain (and transform) a CPU id all across the
IRq layer.
v2: keep move_irq_desc related
[ Impact: cleanup, prepare IRQ code to be NUMA-aware ]
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
LKML-Reference: <49F65536.2020300@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently, when x2apic is not enabled, interrupt remapping
will be enabled in init_dmars(), where it is too late to remap
ioapic interrupts, that is, ioapic interrupts are really in
compatibility mode, not remappable mode.
This patch always enables interrupt remapping before ioapic
setup, it guarantees all interrupts will be remapped when
interrupt remapping is enabled. Thus it doesn't need to set
the compatibility interrupt bit.
[ Impact: refactor intr-remap init sequence, enable fuller remap mode ]
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Weidong Han <weidong.han@intel.com>
Acked-by: David Woodhouse <David.Woodhouse@intel.com>
Cc: iommu@lists.linux-foundation.org
Cc: allen.m.kay@intel.com
Cc: fenghua.yu@intel.com
LKML-Reference: <1239957736-6161-4-git-send-email-weidong.han@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix this build error:
drivers/pci/intr_remapping.c: In function 'ir_parse_ioapic_scope':
drivers/pci/intr_remapping.c:617: error: invalid use of undefined type
'struct acpi_dmar_hardware_unit'
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
If queue invalidation is disabled after it's already initialized,
dmar_enable_qi won't re-enable it due to iommu->qi is allocated.
It may result in system hang when use queue invalidation. Add this
check to avoid this case.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
When extended interrupt mode (x2apic mode) is not supported in a
system, it must set compatibility format interrupt to bypass
interrupt remapping, otherwise compatibility format interrupts
will be blocked.
This will be used when interrupt remapping is enabled while x2apic
is not supported.
Signed-off-by: Weidong Han <weidong.han@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This patch enables suspend/resume for interrupt remapping. During suspend,
interrupt remapping is disabled. When resume, interrupt remapping is enabled
again.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Impact: invalid use of GFP_KERNEL in interrupt context
Queued invalidation and interrupt-remapping will get initialized with
interrupts disabled (while enabling interrupt-remapping). So use
GFP_ATOMIC instead of GFP_KERNEL for memory alloacations.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: fix interrupt table entry leak
Fix the typo which was not clearing all the interrupt remapping table
entries corresponding to an irq.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: cleanup/sanitization
Start from a sane state while enabling dma and interrupt-remapping, by
clearing the previous recorded faults and disabling previously
enabled queued invalidation and interrupt-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: new interfaces (not yet used)
Routines for disabling queued invalidation and interrupt remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: interface augmentation (not yet used)
Enable fault handling flow for intr-remapping aswell. Fault handling
code now shared by both dma-remapping and intr-remapping.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Impact: fix potential deadlock on x2apic
fix "hard-safe -> hard-unsafe lock order detected" with irq_2_ir_lock
On x2apic enabled system:
[ INFO: hard-safe -> hard-unsafe lock order detected ]
2.6.27-03151-g4480f15b #1
------------------------------------------------------
swapper/1 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
(irq_2_ir_lock){--..}, at: [<ffffffff8038ebc0>] get_irte+0x2f/0x95
and this task is already holding:
(&irq_desc_lock_class){+...}, at: [<ffffffff802649ed>] setup_irq+0x67/0x281
which would create a new lock dependency:
(&irq_desc_lock_class){+...} -> (irq_2_ir_lock){--..}
but this new dependency connects a hard-irq-safe lock:
(&irq_desc_lock_class){+...}
... which became hard-irq-safe at:
[<ffffffffffffffff>] 0xffffffffffffffff
to a hard-irq-unsafe lock:
(irq_2_ir_lock){--..}
... which became hard-irq-unsafe at:
... [<ffffffff802547b5>] __lock_acquire+0x571/0x706
[<ffffffff8025499f>] lock_acquire+0x55/0x71
[<ffffffff8062f2c4>] _spin_lock+0x2c/0x38
[<ffffffff8038ee50>] alloc_irte+0x8a/0x14b
[<ffffffff8021f733>] setup_IO_APIC_irq+0x119/0x30e
[<ffffffff8090860e>] setup_IO_APIC+0x146/0x6e5
[<ffffffff809058fc>] native_smp_prepare_cpus+0x24e/0x2e9
[<ffffffff808f982c>] kernel_init+0x5a/0x176
[<ffffffff8020c289>] child_rip+0xa/0x11
[<ffffffffffffffff>] 0xffffffffffffffff
Fix this theoretical lock order issue by using spin_lock_irqsave() instead of
spin_lock()
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
When hardware detects any error with a descriptor from the invalidation
queue, it stops fetching new descriptors from the queue until software
clears the Invalidation Queue Error bit in the Fault Status register.
Following fix handles the IQE so the kernel won't be trapped in an
infinite loop.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Impact: clean up sparseirq fallout on random.c
Ingo suggested to change some ifdef from SPARSE_IRQ to GENERIC_HARDIRQS
so we could some #ifdef later if all arch support genirq
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: build fix
make intr_remapping.c to include smp.h, so could use boot_cpu_id there
also remove old change that disabling sparseirq with !SMP
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new feature
Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.
To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.
When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).
This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu
and x86/uv.
The sparseirq branch is just preliminary groundwork: no sparse IRQs are
actually implemented by this tree anymore - just the new APIs are added
while keeping the old way intact as well (the new APIs map 1:1 to
irq_desc[]). The 'real' sparse IRQ support will then be a relatively
small patch ontop of this - with a v2.6.29 merge target.
* 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits)
genirq: improve include files
intr_remapping: fix typo
io_apic: make irq_mis_count available on 64-bit too
genirq: fix name space collisions of nr_irqs in arch/*
genirq: fix name space collision of nr_irqs in autoprobe.c
genirq: use iterators for irq_desc loops
proc: fixup irq iterator
genirq: add reverse iterator for irq_desc
x86: move ack_bad_irq() to irq.c
x86: unify show_interrupts() and proc helpers
x86: cleanup show_interrupts
genirq: cleanup the sparseirq modifications
genirq: remove artifacts from sparseirq removal
genirq: revert dynarray
genirq: remove irq_to_desc_alloc
genirq: remove sparse irq code
genirq: use inline function for irq_to_desc
genirq: consolidate nr_irqs and for_each_irq_desc()
x86: remove sparse irq from Kconfig
genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
...
This code is not ready, but we need to rip it out instead of rebasing
as we would lose the APIC/IO_APIC unification otherwise.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In irq_2_iommu_alloc() and set_irte_irq(), irq_to_desc or
irq_2_iommu pointers may not be allocated. So use the routines
which will allocate them if they are not already allocated.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
