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2009-06-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguestLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-lguest: (31 commits) lguest: add support for indirect ring entries lguest: suppress notifications in example Launcher lguest: try to batch interrupts on network receive lguest: avoid sending interrupts to Guest when no activity occurs. lguest: implement deferred interrupts in example Launcher lguest: remove obsolete LHREQ_BREAK call lguest: have example Launcher service all devices in separate threads lguest: use eventfds for device notification eventfd: export eventfd_signal and eventfd_fget for lguest lguest: allow any process to send interrupts lguest: PAE fixes lguest: PAE support lguest: Add support for kvm_hypercall4() lguest: replace hypercall name LHCALL_SET_PMD with LHCALL_SET_PGD lguest: use native_set_* macros, which properly handle 64-bit entries when PAE is activated lguest: map switcher with executable page table entries lguest: fix writev returning short on console output lguest: clean up length-used value in example launcher lguest: Segment selectors are 16-bit long. Fix lg_cpu.ss1 definition. lguest: beyond ARRAY_SIZE of cpu->arch.gdt ...
2009-06-12lguest: remove obsolete LHREQ_BREAK callRusty Russell
We no longer need an efficient mechanism to force the Guest back into host userspace, as each device is serviced without bothering the main Guest process (aka. the Launcher). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: use eventfds for device notificationRusty Russell
Currently, when a Guest wants to perform I/O it calls LHCALL_NOTIFY with an address: the main Launcher process returns with this address, and figures out what device to run. A far nicer model is to let processes bind an eventfd to an address: if we find one, we simply signal the eventfd. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Davide Libenzi <davidel@xmailserver.org>
2009-06-12lguest: allow any process to send interruptsRusty Russell
We currently only allow the Launcher process to send interrupts, but it as we already send interrupts from the hrtimer, it's a simple matter of extracting that code into a common set_interrupt routine. As we switch to a thread per virtqueue, this avoids a bottleneck through the main Launcher process. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: PAE fixesRusty Russell
1) j wasn't initialized in setup_pagetables, so they weren't set up for me causing immediate guest crashes. 2) gpte_addr should not re-read the pmd from the Guest. Especially not BUG_ON() based on the value. If we ever supported SMP guests, they could trigger that. And the Launcher could also trigger it (tho currently root-only). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: PAE supportMatias Zabaljauregui
This version requires that host and guest have the same PAE status. NX cap is not offered to the guest, yet. Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: replace hypercall name LHCALL_SET_PMD with LHCALL_SET_PGDMatias Zabaljauregui
replace LHCALL_SET_PMD with LHCALL_SET_PGD hypercall name (That's really what it is, and the confusion gets worse with PAE support) Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Reported-by: Jeremy Fitzhardinge <jeremy@goop.org>
2009-06-12lguest: use native_set_* macros, which properly handle 64-bit entries when ↵Matias Zabaljauregui
PAE is activated Some cleanups and replace direct assignment with native_set_* macros which properly handle 64-bit entries when PAE is activated Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: map switcher with executable page table entriesMatias Zabaljauregui
Map switcher with executable page table entries. (This bug didn't matter before PAE and hence NX support -- RR) Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: Segment selectors are 16-bit long. Fix lg_cpu.ss1 definition.Matias Zabaljauregui
If GDT_ENTRIES were every > 256, this could become a problem. Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: beyond ARRAY_SIZE of cpu->arch.gdtRoel Kluin
Do not go beyond ARRAY_SIZE of cpu->arch.gdt Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: improve interrupt handling, speed up stream networkingRusty Russell
lguest never checked for pending interrupts when enabling interrupts, and things still worked. However, it makes a significant difference to TCP performance, so it's time we fixed it by introducing a pending_irq flag and checking it on irq_restore and irq_enable. These two routines are now too big to patch into the 8/10 bytes patch space, so we drop that code. Note: The high latency on interrupt delivery had a very curious effect: once everything else was optimized, networking without GSO was faster than networking with GSO, since more interrupts were sent and hence a greater chance of one getting through to the Guest! Note2: (Almost) Closing the same loophole for iret doesn't have any measurable effect, so I'm leaving that patch for the moment. Before: 1GB tcpblast Guest->Host: 30.7 seconds 1GB tcpblast Guest->Host (no GSO): 76.0 seconds After: 1GB tcpblast Guest->Host: 6.8 seconds 1GB tcpblast Guest->Host (no GSO): 27.8 seconds Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: fix race in halt codeRusty Russell
When the Guest does the LHCALL_HALT hypercall, we go to sleep, expecting that a timer or the Waker will wake_up_process() us. But we do it in a stupid way, leaving a classic missing wakeup race. So split maybe_do_interrupt() into interrupt_pending() and try_deliver_interrupt(), and check maybe_do_interrupt() and the "break_out" flag before calling schedule. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12lguest: fix lguest wake on guest clock tick, or fd activityRusty Russell
The Launcher could be inside the Guest on another CPU; wake_up_process will do nothing because it is "running". kick_process will knock it back into our kernel in this case, otherwise we'll miss it until the next guest exit. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-06-12virtio: find_vqs/del_vqs virtio operationsMichael S. Tsirkin
This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations, and updates all drivers. This is needed for MSI support, because MSI needs to know the total number of vectors upfront. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ lguest/9p compile fixes)
2009-06-12virtio: add names to virtqueue struct, mapping from devices to queues.Rusty Russell
Add a linked list of all virtqueues for a virtio device: this helps for debugging and is also needed for upcoming interface change. Also, add a "name" field for clearer debug messages. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-05-26lguest: fix on Intel when KVM loaded (unhandled trap 13)Rusty Russell
When KVM is loaded, and hence VT set up, the vmcall instruction in an lguest guest causes a #GP, not #UD. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-19lguest: fix guest crash on non-linear addresses in gdt pvopsRusty Russell
Fixes guest crash 'lguest: bad read address 0x4800000 len 256' The new per-cpu allocator ends up handing a non-linear address to write_gdt_entry. We do __pa() on it, and hand it to the host, which kills us. I've long wanted to make the hypercall "LOAD_GDT_ENTRY" to match the IDT code, but had no pressing reason until now. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: lguest@ozlabs.org
2009-04-19lguest: fix crash on vmlinux imagesMatias Zabaljauregui
Typical message: 'lguest: unhandled trap 6 at 0x418726 (0x0)' vmlinux guests were broken by 4cd8b5e2a159f18a1507f1187b44a1acbfa6341b 'lguest: use KVM hypercalls', which rewrites guest text from kvm hypercalls to trap 31. The Launcher mmaps the kernel image. The Guest executes and immediately faults in the first text page (read-only). Then it hits a hypercall, and we rewrite that hypercall, causing a copy-on-write. But the Guest pagetables still refer to the old page: we fault again, but as Host we see the hypercall already rewritten, and pass the fault back to the Guest. The Guest hasn't set up an IDT yet, so we kill it. This doesn't happen with bzImages: they unpack themselves and so the text pages are already read-write. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Tested-by: Patrick McHardy <kaber@trash.net>
2009-03-30lguest: use bool instead of intMatias Zabaljauregui
Impact: clean up Rusty told me, some time ago, that he had become a fan of "bool". So, here are some replacements. Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-30lguest: use KVM hypercallsMatias Zabaljauregui
Impact: cleanup This patch allow us to use KVM hypercalls Signed-off-by: Matias Zabaljauregui <zabaljauregui at gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-03-30lguest: fix spurious BUG_ON() on invalid guest stack.Rusty Russell
Impact: fix crash on misbehaving guest gpte_addr() contains a BUG_ON(), insisting that the present flag is set. We need to return before we call it if that isn't the case. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: stable@kernel.org
2009-03-27Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2Ingo Molnar
Conflicts: arch/parisc/kernel/irq.c arch/x86/include/asm/fixmap_64.h arch/x86/include/asm/setup.h kernel/irq/handle.c Semantic merge: arch/x86/include/asm/fixmap.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-09lguest: fix for CONFIG_SPARSE_IRQ=yRusty Russell
Impact: remove lots of lguest boot WARN_ON() when CONFIG_SPARSE_IRQ=y We now need to call irq_to_desc_alloc_cpu() before set_irq_chip_and_handler_name(), but we can't do that from init_IRQ (no kmalloc available). So do it as we use interrupts instead. Also means we only alloc for irqs we use, which was the intent of CONFIG_SPARSE_IRQ anyway. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com>
2009-02-23x86: remove the Voyager 32-bit subarchIngo Molnar
Impact: remove unused/broken code The Voyager subarch last built successfully on the v2.6.26 kernel and has been stale since then and does not build on the v2.6.27, v2.6.28 and v2.6.29-rc5 kernels. No actual users beyond the maintainer reported this breakage. Patches were sent and most of the fixes were accepted but the discussion around how to do a few remaining issues cleanly fizzled out with no resolution and the code remained broken. In the v2.6.30 x86 tree development cycle 32-bit subarch support has been reworked and removed - and the Voyager code, beyond the build problems already known, needs serious and significant changes and probably a rewrite to support it. CONFIG_X86_VOYAGER has been marked BROKEN then. The maintainer has been notified but no patches have been sent so far to fix it. While all other subarchs have been converted to the new scheme, voyager is still broken. We'd prefer to receive patches which clean up the current situation in a constructive way, but even in case of removal there is no obstacle to add that support back after the issues have been sorted out in a mutually acceptable fashion. So remove this inactive code for now. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-30lguest: Fix a memory leak with the lg object during launcher closeMark Wallis
Fix a memory leak identified by Rusty Russell during LCA09 by kfree'ing the lg object instead of just clearing it when the launcher closes. Signed-off-by: Mark Wallis <mwallis@serialmonkey.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-30lguest: typos fixAtsushi SAKAI
3 points lguest_asm.S => i386_head.S LHCALL_BREAK => LHREQ_BREAK perferred => preferred Signed-off-by: Atsushi SAKAI <sakaia@jp.fujitsu.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-01-06lguest: do not statically allocate root deviceMark McLoughlin
We shouldn't be statically allocating the root device object, so dynamically allocate it using root_device_register() instead. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-01-02Merge branch 'cpus4096-for-linus-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'cpus4096-for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (66 commits) x86: export vector_used_by_percpu_irq x86: use logical apicid in x2apic_cluster's x2apic_cpu_mask_to_apicid_and() sched: nominate preferred wakeup cpu, fix x86: fix lguest used_vectors breakage, -v2 x86: fix warning in arch/x86/kernel/io_apic.c sched: fix warning in kernel/sched.c sched: move test_sd_parent() to an SMP section of sched.h sched: add SD_BALANCE_NEWIDLE at MC and CPU level for sched_mc>0 sched: activate active load balancing in new idle cpus sched: bias task wakeups to preferred semi-idle packages sched: nominate preferred wakeup cpu sched: favour lower logical cpu number for sched_mc balance sched: framework for sched_mc/smt_power_savings=N sched: convert BALANCE_FOR_xx_POWER to inline functions x86: use possible_cpus=NUM to extend the possible cpus allowed x86: fix cpu_mask_to_apicid_and to include cpu_online_mask x86: update io_apic.c to the new cpumask code x86: Introduce topology_core_cpumask()/topology_thread_cpumask() x86: xen: use smp_call_function_many() x86: use work_on_cpu in x86/kernel/cpu/mcheck/mce_amd_64.c ... Fixed up trivial conflict in kernel/time/tick-sched.c manually
2008-12-30lguest: struct device - replace bus_id with dev_name()Mark McLoughlin
bus_id is gradually being removed, so use dev_name() instead. Signed-off-by: Mark McLoughlin <markmc@redhat.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30lguest: move the initial guest page table creation code to the hostMatias Zabaljauregui
This patch moves the initial guest page table creation code to the host, so the launcher keeps working with PAE enabled configs. Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-30virtio: hand virtio ring alignment as argument to vring_new_virtqueueRusty Russell
This allows each virtio user to hand in the alignment appropriate to their virtio_ring structures. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
2008-12-30virtio: use LGUEST_VRING_ALIGN instead of relying on pagesizeRusty Russell
This doesn't really matter, since lguest is i386 only at the moment, but we could actually choose a different value. (lguest doesn't have a guarenteed ABI). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-12-23x86: fix lguest used_vectors breakage, -v2Yinghai Lu
Impact: fix lguest, clean up 32-bit lguest used used_vectors to record vectors, but that model of allocating vectors changed and got broken, after we changed vector allocation to a per_cpu array. Try enable that for 64bit, and the array is used for all vectors that are not managed by vector_irq per_cpu array. Also kill system_vectors[], that is now a duplication of the used_vectors bitmap. [ merged in cpus4096 due to io_apic.c cpumask changes. ] [ -v2, fix build failure ] Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-26lguest: update commentryRusty Russell
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-08-12lguest: use get_user_pages_fast() instead of get_user_pages()Rusty Russell
Using a simple page table thrashing program I measure a slight improvement. The program creates five processes. Each touches 1000 pages then schedules the next process. We repeat this 1000 times. As lguest only caches 4 cr3 values, this rebuilds a lot of shadow page tables requiring virt->phys mappings. Before: 5.93 seconds After: 5.40 seconds (Counts of slow vs fastpath in this usage are 6092 and 2852462 respectively.) And more importantly for lguest, the code is simpler. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29lguest: use cpu capability accessorsAndrew Morton
To support my little make-x86-bitops-use-proper-typechecking projectlet. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrea Arcangeli <andrea@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29lguest: fix switcher_page leak on unloadJohannes Weiner
map_switcher allocates the array, unmap_switcher has to free it accordingly. Signed-off-by: Johannes Weiner <hannes@saeurebad.de> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-29lguest: Guest int3 fixRusty Russell
Ron Minnich noticed that guest userspace gets a GPF when it tries to int3: we need to copy the privilege level from the guest-supplied IDT to the real IDT. int3 is the only common case where guest userspace expects to invoke an interrupt, so that's the symptom of failing to do this. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25virtio: Add transport feature handling stub for virtio_ring.Rusty Russell
To prepare for virtio_ring transport feature bits, hook in a call in all the users to manipulate them. This currently just clears all the bits, since it doesn't understand any features. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-25virtio: Rename set_features to finalize_featuresRusty Russell
Rather than explicitly handing the features to the lower-level, we just hand the virtio_device and have it set the features. This make it clear that it has the chance to manipulate the features of the device at this point (and that all feature negotiation is already done). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-07-15Merge branch 'generic-ipi' into generic-ipi-for-linusIngo Molnar
Conflicts: arch/powerpc/Kconfig arch/s390/kernel/time.c arch/x86/kernel/apic_32.c arch/x86/kernel/cpu/perfctr-watchdog.c arch/x86/kernel/i8259_64.c arch/x86/kernel/ldt.c arch/x86/kernel/nmi_64.c arch/x86/kernel/smpboot.c arch/x86/xen/smp.c include/asm-x86/hw_irq_32.h include/asm-x86/hw_irq_64.h include/asm-x86/mach-default/irq_vectors.h include/asm-x86/mach-voyager/irq_vectors.h include/asm-x86/smp.h kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-10x86, VisWS: turn into generic arch, eliminate Kconfig specialsIngo Molnar
remove leftover traces of various VISWS related Kconfig specials. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-26on_each_cpu(): kill unused 'retry' parameterJens Axboe
It's not even passed on to smp_call_function() anymore, since that was removed. So kill it. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-06-25Merge commit 'v2.6.26-rc8' into x86/xenIngo Molnar
Conflicts: arch/x86/xen/enlighten.c arch/x86/xen/mmu.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-20x86: fix NULL pointer deref in __switch_toSuresh Siddha
I am able to reproduce the oops reported by Simon in __switch_to() with lguest. My debug showed that there is at least one lguest specific issue (which should be present in 2.6.25 and before aswell) and it got exposed with a kernel oops with the recent fpu dynamic allocation patches. In addition to the previous possible scenario (with fpu_counter), in the presence of lguest, it is possible that the cpu's TS bit it still set and the lguest launcher task's thread_info has TS_USEDFPU still set. This is because of the way the lguest launcher handling the guest's TS bit. (look at lguest_set_ts() in lguest_arch_run_guest()). This can result in a DNA fault while doing unlazy_fpu() in __switch_to(). This will end up causing a DNA fault in the context of new process thats getting context switched in (as opossed to handling DNA fault in the context of lguest launcher/helper process). This is wrong in both pre and post 2.6.25 kernels. In the recent 2.6.26-rc series, this is showing up as NULL pointer dereferences or sleeping function called from atomic context(__switch_to()), as we free and dynamically allocate the FPU context for the newly created threads. Older kernels might show some FPU corruption for processes running inside of lguest. With the appended patch, my test system is running for more than 50 mins now. So atleast some of your oops (hopefully all!) should get fixed. Please give it a try. I will spend more time with this fix tomorrow. Reported-by: Simon Holm Thøgersen <odie@cs.aau.dk> Reported-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-16Merge branch 'linus' into x86/xenIngo Molnar
2008-05-30virtio: set device index in common code.Rusty Russell
Anthony Liguori points out that three different transports use the virtio code, but each one keeps its own counter to set the virtio_device's index field. In theory (though not in current practice) this means that names could be duplicated, and that risk grows as more transports are created. So we move the selection of the unique virtio_device.index into the common code in virtio.c, which has the side-benefit of removing duplicate code. The only complexity is that lguest and S/390 use the index to uniquely identify the device in case of catastrophic failure before register_virtio_device() is called: now we use the offset within the descriptor page as a unique identifier for the printks. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chris Lalancette <clalance@redhat.com> Cc: Anthony Liguori <anthony@codemonkey.ws>
2008-05-30lguest: use ioremap_cache, not ioremapRusty Russell
Thanks to Jon Corbet & LWN. Only took me a day to join the dots. Host->Guest netcat before (with unnecessily large receive buffers): 1073741824 bytes (1.1 GB) copied, 24.7528 seconds, 43.4 MB/s After: 1073741824 bytes (1.1 GB) copied, 17.6369 seconds, 60.9 MB/s Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-05-27x86/paravirt: add pte_flags to just get pte flagsJeremy Fitzhardinge
Add pte_flags() to extract the flags from a pte. This is a special case of pte_val() which is only guaranteed to return the pte's flags correctly; the page number may be corrupted or missing. The intent is to allow paravirt implementations to return pte flags without having to do any translation of the page number (most notably, Xen). Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>