* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (75 commits)
PCI hotplug: clean up acpi_run_hpp()
PCI hotplug: acpiphp: use generic pci_configure_slot()
PCI hotplug: shpchp: use generic pci_configure_slot()
PCI hotplug: pciehp: use generic pci_configure_slot()
PCI hotplug: add pci_configure_slot()
PCI hotplug: clean up acpi_get_hp_params_from_firmware() interface
PCI hotplug: acpiphp: don't cache hotplug_params in acpiphp_bridge
PCI hotplug: acpiphp: remove superfluous _HPP/_HPX evaluation
PCI: Clear saved_state after the state has been restored
PCI PM: Return error codes from pci_pm_resume()
PCI: use dev_printk in quirk messages
PCI / PCIe portdrv: Fix pcie_portdrv_slot_reset()
PCI Hotplug: convert acpi_pci_detect_ejectable() to take an acpi_handle
PCI Hotplug: acpiphp: find bridges the easy way
PCI: pcie portdrv: remove unused variable
PCI / ACPI PM: Propagate wake-up enable for devices w/o ACPI support
ACPI PM: Replace wakeup.prepared with reference counter
PCI PM: Introduce device flag wakeup_prepared
PCI / ACPI PM: Rework some debug messages
PCI PM: Simplify PCI wake-up code
...
Fixed up conflict in arch/powerpc/kernel/pci_64.c due to OF device tree
scanning having been moved and merged for the 32- and 64-bit cases. The
'needs_freset' initialization added in 6e19314cc ("PCI/powerpc: support
PCIe fundamental reset") is now in arch/powerpc/kernel/pci_of_scan.c.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (46 commits)
powerpc64: convert to dynamic percpu allocator
sparc64: use embedding percpu first chunk allocator
percpu: kill lpage first chunk allocator
x86,percpu: use embedding for 64bit NUMA and page for 32bit NUMA
percpu: update embedding first chunk allocator to handle sparse units
percpu: use group information to allocate vmap areas sparsely
vmalloc: implement pcpu_get_vm_areas()
vmalloc: separate out insert_vmalloc_vm()
percpu: add chunk->base_addr
percpu: add pcpu_unit_offsets[]
percpu: introduce pcpu_alloc_info and pcpu_group_info
percpu: move pcpu_lpage_build_unit_map() and pcpul_lpage_dump_cfg() upward
percpu: add @align to pcpu_fc_alloc_fn_t
percpu: make @dyn_size mandatory for pcpu_setup_first_chunk()
percpu: drop @static_size from first chunk allocators
percpu: generalize first chunk allocator selection
percpu: build first chunk allocators selectively
percpu: rename 4k first chunk allocator to page
percpu: improve boot messages
percpu: fix pcpu_reclaim() locking
...
Fix trivial conflict as by Tejun Heo in kernel/sched.c
* 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, pat: Fix cacheflush address in change_page_attr_set_clr()
mm: remove !NUMA condition from PAGEFLAGS_EXTENDED condition set
x86: Fix earlyprintk=dbgp for machines without NX
x86, pat: Sanity check remap_pfn_range for RAM region
x86, pat: Lookup the protection from memtype list on vm_insert_pfn()
x86, pat: Add lookup_memtype to get the current memtype of a paddr
x86, pat: Use page flags to track memtypes of RAM pages
x86, pat: Generalize the use of page flag PG_uncached
x86, pat: Add rbtree to do quick lookup in memtype tracking
x86, pat: Add PAT reserve free to io_mapping* APIs
x86, pat: New i/f for driver to request memtype for IO regions
x86, pat: ioremap to follow same PAT restrictions as other PAT users
x86, pat: Keep identity maps consistent with mmaps even when pat_disabled
x86, mtrr: make mtrr_aps_delayed_init static bool
x86, pat/mtrr: Rendezvous all the cpus for MTRR/PAT init
generic-ipi: Allow cpus not yet online to call smp_call_function with irqs disabled
x86: Fix an incorrect argument of reserve_bootmem()
x86: Fix system crash when loading with "reservetop" parameter
* 'agp-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/agp-2.6:
agp/intel: remove restore in resume
agp: fix uninorth build
intel-agp: Set dma mask for i915
agp: kill phys_to_gart() and gart_to_phys()
intel-agp: fix sglist allocation to avoid vmalloc()
intel-agp: Move repeated sglist free into separate function
agp: Switch agp_{un,}map_page() to take struct page * argument
agp: tidy up handling of scratch pages w.r.t. DMA API
intel_agp: Use PCI DMA API correctly on chipsets new enough to have IOMMU
agp: Add generic support for graphics dma remapping
agp: Switch mask_memory() method to take address argument again, not page
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: (23 commits)
at_hdmac: Rework suspend_late()/resume_early()
PM: Reset transition_started at dpm_resume_noirq
PM: Update kerneldoc comments in drivers/base/power/main.c
PM: Add convenience macro to make switching to dev_pm_ops less error-prone
hp-wmi: Switch driver to dev_pm_ops
floppy: Switch driver to dev_pm_ops
PM: Trivial fixes
PM / Hibernate / Memory hotplug: Always use for_each_populated_zone()
PM/Hibernate: Do not try to allocate too much memory too hard (rev. 2)
PM/Hibernate: Do not release preallocated memory unnecessarily (rev. 2)
PM/Hibernate: Rework shrinking of memory
PM: Fix typo in label name s/Platofrm_finish/Platform_finish/
PM: Run-time PM platform device bus support
PM: Introduce core framework for run-time PM of I/O devices (rev. 17)
Driver Core: Make PM operations a const pointer
PM: Remove platform device suspend_late()/resume_early() V2
USB: Rework musb suspend()/resume_early()
I2C: Rework i2c-s3c2410 suspend_late()/resume() V2
I2C: Rework i2c-pxa suspend_late()/resume_early()
DMA: Rework txx9dmac suspend_late()/resume_early()
...
Fix trivial conflict in drivers/base/platform.c (due to same
constification patch being merged in both sides, along with some other
PM work in the PM branch)
* 'kvm-updates/2.6.32' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (202 commits)
MAINTAINERS: update KVM entry
KVM: correct error-handling code
KVM: fix compile warnings on s390
KVM: VMX: Check cpl before emulating debug register access
KVM: fix misreporting of coalesced interrupts by kvm tracer
KVM: x86: drop duplicate kvm_flush_remote_tlb calls
KVM: VMX: call vmx_load_host_state() only if msr is cached
KVM: VMX: Conditionally reload debug register 6
KVM: Use thread debug register storage instead of kvm specific data
KVM guest: do not batch pte updates from interrupt context
KVM: Fix coalesced interrupt reporting in IOAPIC
KVM guest: fix bogus wallclock physical address calculation
KVM: VMX: Fix cr8 exiting control clobbering by EPT
KVM: Optimize kvm_mmu_unprotect_page_virt() for tdp
KVM: Document KVM_CAP_IRQCHIP
KVM: Protect update_cr8_intercept() when running without an apic
KVM: VMX: Fix EPT with WP bit change during paging
KVM: Use kvm_{read,write}_guest_virt() to read and write segment descriptors
KVM: x86 emulator: Add adc and sbb missing decoder flags
KVM: Add missing #include
...
console_print() is an old legacy interface mostly unused in the entire
kernel tree. It's best to clean up its existing use and let developers
use their own implementation of it as they feel fit.
Signed-off-by: Anirban Sinha <asinha@zeugmasystems.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1623 commits)
netxen: update copyright
netxen: fix tx timeout recovery
netxen: fix file firmware leak
netxen: improve pci memory access
netxen: change firmware write size
tg3: Fix return ring size breakage
netxen: build fix for INET=n
cdc-phonet: autoconfigure Phonet address
Phonet: back-end for autoconfigured addresses
Phonet: fix netlink address dump error handling
ipv6: Add IFA_F_DADFAILED flag
net: Add DEVTYPE support for Ethernet based devices
mv643xx_eth.c: remove unused txq_set_wrr()
ucc_geth: Fix hangs after switching from full to half duplex
ucc_geth: Rearrange some code to avoid forward declarations
phy/marvell: Make non-aneg speed/duplex forcing work for 88E1111 PHYs
drivers/net/phy: introduce missing kfree
drivers/net/wan: introduce missing kfree
net: force bridge module(s) to be GPL
Subject: [PATCH] appletalk: Fix skb leak when ipddp interface is not loaded
...
Fixed up trivial conflicts:
- arch/x86/include/asm/socket.h
converted to <asm-generic/socket.h> in the x86 tree. The generic
header has the same new #define's, so that works out fine.
- drivers/net/tun.c
fix conflict between 89f56d1e9 ("tun: reuse struct sock fields") that
switched over to using 'tun->socket.sk' instead of the redundantly
available (and thus removed) 'tun->sk', and 2b980dbd ("lsm: Add hooks
to the TUN driver") which added a new 'tun->sk' use.
Noted in 'next' by Stephen Rothwell.
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (28 commits)
rcu: Move end of special early-boot RCU operation earlier
rcu: Changes from reviews: avoid casts, fix/add warnings, improve comments
rcu: Create rcutree plugins to handle hotplug CPU for multi-level trees
rcu: Remove lockdep annotations from RCU's _notrace() API members
rcu: Add #ifdef to suppress __rcu_offline_cpu() warning in !HOTPLUG_CPU builds
rcu: Add CPU-offline processing for single-node configurations
rcu: Add "notrace" to RCU function headers used by ftrace
rcu: Remove CONFIG_PREEMPT_RCU
rcu: Merge preemptable-RCU functionality into hierarchical RCU
rcu: Simplify rcu_pending()/rcu_check_callbacks() API
rcu: Use debugfs_remove_recursive() simplify code.
rcu: Merge per-RCU-flavor initialization into pre-existing macro
rcu: Fix online/offline indication for rcudata.csv trace file
rcu: Consolidate sparse and lockdep declarations in include/linux/rcupdate.h
rcu: Renamings to increase RCU clarity
rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.h
rcu: Expunge lingering references to CONFIG_CLASSIC_RCU, optimize on !SMP
rcu: Delay rcu_barrier() wait until beginning of next CPU-hotunplug operation.
rcu: Fix typo in rcu_irq_exit() comment header
rcu: Make rcupreempt_trace.c look at offline CPUs
...
* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (59 commits)
x86/gart: Do not select AGP for GART_IOMMU
x86/amd-iommu: Initialize passthrough mode when requested
x86/amd-iommu: Don't detach device from pt domain on driver unbind
x86/amd-iommu: Make sure a device is assigned in passthrough mode
x86/amd-iommu: Align locking between attach_device and detach_device
x86/amd-iommu: Fix device table write order
x86/amd-iommu: Add passthrough mode initialization functions
x86/amd-iommu: Add core functions for pd allocation/freeing
x86/dma: Mark iommu_pass_through as __read_mostly
x86/amd-iommu: Change iommu_map_page to support multiple page sizes
x86/amd-iommu: Support higher level PTEs in iommu_page_unmap
x86/amd-iommu: Remove old page table handling macros
x86/amd-iommu: Use 2-level page tables for dma_ops domains
x86/amd-iommu: Remove bus_addr check in iommu_map_page
x86/amd-iommu: Remove last usages of IOMMU_PTE_L0_INDEX
x86/amd-iommu: Change alloc_pte to support 64 bit address space
x86/amd-iommu: Introduce increase_address_space function
x86/amd-iommu: Flush domains if address space size was increased
x86/amd-iommu: Introduce set_dte_entry function
x86/amd-iommu: Add a gneric version of amd_iommu_flush_all_devices
...
Remove kvm_cpu_has_interrupt() and kvm_arch_interrupt_allowed() from
interface between general code and arch code. kvm_arch_vcpu_runnable()
checks for interrupts instead.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This changes bus accesses to use high-level kvm_io_bus_read/kvm_io_bus_write
functions. in_range now becomes unused so it is removed from device ops in
favor of read/write callbacks performing range checks internally.
This allows aliasing (mostly for in-kernel virtio), as well as better error
handling by making it possible to pass errors up to userspace.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Archs are free to use vcpu_id as they see fit. For x86 it is used as
vcpu's apic id. New ioctl is added to configure boot vcpu id that was
assumed to be 0 till now.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Protect irq injection/acking data structures with a separate irq_lock
mutex. This fixes the following deadlock:
CPU A CPU B
kvm_vm_ioctl_deassign_dev_irq()
mutex_lock(&kvm->lock); worker_thread()
-> kvm_deassign_irq() -> kvm_assigned_dev_interrupt_work_handler()
-> deassign_host_irq() mutex_lock(&kvm->lock);
-> cancel_work_sync() [blocked]
[gleb: fix ia64 path]
Reported-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Init the itc_offset for all possible vCPUs. The current code by
mistake ends up only initializing the offset on vCPU 0.
Spotted by Gleb Natapov.
Signed-off-by: Jes Sorensen <jes@sgi.com>
Acked-by : Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This was #define'd as 0 on all platforms, so let's get rid of it.
This change makes pci_scan_slot() slightly easier to read.
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Russell King <linux@arm.linux.org.uk>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The 32-bit parameters (len and csum) of csum_ipv6_magic() are passed in 64-bit
registers in2 and in4. The high order 32 bits of the registers were never
cleared, and garbage was sometimes calculated into the checksum.
Fix this by clearing the high order 32 bits of these registers.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/dma-mapping.c:14: warning: control reaches end of non-void function
arch/ia64/kernel/dma-mapping.c:14: warning: no return statement in function returning non-void
This warning was introduced by commit: 390bd132b2
Add dma_debug_init() for ia64
Signed-off-by: Tony Luck <tony.luck@intel.com>
Add a keyctl to install a process's session keyring onto its parent. This
replaces the parent's session keyring. Because the COW credential code does
not permit one process to change another process's credentials directly, the
change is deferred until userspace next starts executing again. Normally this
will be after a wait*() syscall.
To support this, three new security hooks have been provided:
cred_alloc_blank() to allocate unset security creds, cred_transfer() to fill in
the blank security creds and key_session_to_parent() - which asks the LSM if
the process may replace its parent's session keyring.
The replacement may only happen if the process has the same ownership details
as its parent, and the process has LINK permission on the session keyring, and
the session keyring is owned by the process, and the LSM permits it.
Note that this requires alteration to each architecture's notify_resume path.
This has been done for all arches barring blackfin, m68k* and xtensa, all of
which need assembly alteration to support TIF_NOTIFY_RESUME. This allows the
replacement to be performed at the point the parent process resumes userspace
execution.
This allows the userspace AFS pioctl emulation to fully emulate newpag() and
the VIOCSETTOK and VIOCSETTOK2 pioctls, all of which require the ability to
alter the parent process's PAG membership. However, since kAFS doesn't use
PAGs per se, but rather dumps the keys into the session keyring, the session
keyring of the parent must be replaced if, for example, VIOCSETTOK is passed
the newpag flag.
This can be tested with the following program:
#include <stdio.h>
#include <stdlib.h>
#include <keyutils.h>
#define KEYCTL_SESSION_TO_PARENT 18
#define OSERROR(X, S) do { if ((long)(X) == -1) { perror(S); exit(1); } } while(0)
int main(int argc, char **argv)
{
key_serial_t keyring, key;
long ret;
keyring = keyctl_join_session_keyring(argv[1]);
OSERROR(keyring, "keyctl_join_session_keyring");
key = add_key("user", "a", "b", 1, keyring);
OSERROR(key, "add_key");
ret = keyctl(KEYCTL_SESSION_TO_PARENT);
OSERROR(ret, "KEYCTL_SESSION_TO_PARENT");
return 0;
}
Compiled and linked with -lkeyutils, you should see something like:
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
355907932 --alswrv 4043 -1 \_ keyring: _uid.4043
[dhowells@andromeda ~]$ /tmp/newpag
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: _ses
1055658746 --alswrv 4043 4043 \_ user: a
[dhowells@andromeda ~]$ /tmp/newpag hello
[dhowells@andromeda ~]$ keyctl show
Session Keyring
-3 --alswrv 4043 4043 keyring: hello
340417692 --alswrv 4043 4043 \_ user: a
Where the test program creates a new session keyring, sticks a user key named
'a' into it and then installs it on its parent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Reason: Change to is_new_memtype_allowed() in x86/urgent
Resolved semantic conflicts in:
arch/x86/mm/pat.c
arch/x86/mm/ioremap.c
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Only IA64 was using PG_uncached as of now. We now intend to use this bit
in x86 as well, to keep track of memory type of those addresses that
have page struct for them. So, generalize the use of that bit across
ia64 and x86.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Conflicts:
arch/sparc/kernel/smp_64.c
arch/x86/kernel/cpu/perf_counter.c
arch/x86/kernel/setup_percpu.c
drivers/cpufreq/cpufreq_ondemand.c
mm/percpu.c
Conflicts in core and arch percpu codes are mostly from commit
ed78e1e078dd44249f88b1dd8c76dafb39567161 which substituted many
num_possible_cpus() with nr_cpu_ids. As for-next branch has moved all
the first chunk allocators into mm/percpu.c, the changes are moved
from arch code to mm/percpu.c.
Signed-off-by: Tejun Heo <tj@kernel.org>
Between GCC version 3.4.0 and 4.3.3 (including 3.4.0 and 4.3.3), -mtune=merced
is implemented in GCC. Starting from 4.4.0, -mtune=merced is deprecated.
Even implemented in versions between 3.4.0 and 4.3.3, the -mtune=merced
feature has been broken in some of the versions. For example, GCC 4.1.2 reports
interanl tuning function errors during kernel building with -mtune=merced. Or
GCC Bugzilla 16130 reports another -mtune=merced issue on GCC 3.4.1.
So I would remove the -mtune=merced from IA64 kernel build. Without this option,
kernel on Merced will remain the same except losing an unstable and out-of-date
performance tunning feature.
Since GCC version 3.4.0, -mtune=mckinley has been implemented. The
-mtune=mckinley option functions the same as mtune=itanium2. And mtune=itanium2
is the default option. So we don't need to add mtune=mckinley either since its
been the default option in any GCC version which implements this option.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/include/asm/pgtable.h: asm/processor.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
fix the following 'make includecheck' warning:
arch/ia64/kernel/ia64_ksyms.c: asm/page.h is included more than once.
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
__test_and_clear_bit() returns a bitfield with the tested-for bit set.
Make it consistent with the other bitops - of ia64 but also every
other architecture - and return a boolean value.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Fenghua Yu <fenghua.yu@intel.com>
In commit 160c1d8e40,
dma_ops->dma_supported = iommu_dma_supported;
This dma_ops->dma_supported is first called in platform_dma_init() during kernel
boot. Then dma_ops->dma_supported will be called recursively in
iommu_dma_supported.
Kernel can not boot because kernel can not get out of iommu_dma_supported until
it runs out of stack memory.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
flush_write_buffers() in dma-mapping-common.h was removed so we
can remove NULL flush_write_buffers() in IA64.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: davem@davemloft.net
LKML-Reference: <1249872797-1314-3-git-send-email-fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This sockopt goes in line with SO_TYPE and SO_PROTOCOL. It makes it
possible for userspace programs to pass around file descriptors — I
am referring to arguments-to-functions, but it may even work for the
fd passing over UNIX sockets — without needing to also pass the
auxiliary information (PF_INET6/IPPROTO_TCP).
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to SO_TYPE returning the socket type, SO_PROTOCOL allows to
retrieve the protocol used with a given socket.
I am not quite sure why we have that-many copies of socket.h, and why
the values are not the same on all arches either, but for where hex
numbers dominate, I use 0x1029 for SO_PROTOCOL as that seems to be
the next free unused number across a bunch of operating systems, or
so Google results make me want to believe. SO_PROTOCOL for others
just uses the next free Linux number, 38.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds two functions, phys_to_dma() and dma_to_phys() to x86, IA64
and powerpc. swiotlb uses them. phys_to_dma() converts a physical
address to a dma address. dma_to_phys() does the opposite.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Becky Bruce <beckyb@kernel.crashing.org>
Linus Torvalds