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2008-12-10atomic: fix a typo in atomic_long_xchg()Eric Dumazet
atomic_long_xchg() is not correctly defined for 32bit arches. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-09[PATCH] asm/generic: fix bug - kernel fails to build when enable some common ↵Mike Frysinger
audit code on Blackfin If you enable some common audit code, the kernel fails to build. In file included from lib/audit.c:17: include/asm-generic/audit_write.h:3: error: '__NR_swapon' undeclared here (not in a function) make[1]: *** [lib/audit.o] Error 1 make: *** [lib] Error 2 So do not use __NR_swapon if it isnt defined for a port. Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-11-08Fix __pfn_to_page(pfn) for CONFIG_DISCONTIGMEM=yRafael J. Wysocki
Fix the __pfn_to_page(pfn) macro so that it doesn't evaluate its argument twice in the CONFIG_DISCONTIGMEM=y case, because 'pfn' may be a result of a funtion call having side effects. For example, the hibernation code applies pfn_to_page(pfn) to the result of a function returning the pfn corresponding to the next set bit in a bitmap and the current bit position is modified on each call. This leads to "interesting" failures for CONFIG_DISCONTIGMEM=y due to the current behavior of __pfn_to_page(pfn). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-27asm-generic: define DIE_OOPS in asm-genericJonas Bonn
Impact: build fix DIE_OOPS is now used in the generic trace handling code so it needs to be defined for all architectures. Define it in asm-generic so that it's available to all by default and doesn't cause build errors for architectures that rely on the generic implementation. Signed-off-by: Jonas Bonn <jonas.bonn@gmail.com> Acked-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-23mutex: speed up generic mutex implementationsNick Piggin
- atomic operations which both modify the variable and return something imply full smp memory barriers before and after the memory operations involved (failing atomic_cmpxchg, atomic_add_unless, etc don't imply a barrier because they don't modify the target). See Documentation/atomic_ops.txt. So remove extra barriers and branches. - All architectures support atomic_cmpxchg. This has no relation to __HAVE_ARCH_CMPXCHG. We can just take the atomic_cmpxchg path unconditionally This reduces a simple single threaded fastpath lock+unlock test from 590 cycles to 203 cycles on a ppc970 system. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20fix WARN() for PPCArjan van de Ven
powerpc doesn't use the generic WARN_ON infrastructure. The newly introduced WARN() as a result didn't print the message, this patch adds the printk for this specific case. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20Merge branch 'tracing-v28-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (131 commits) tracing/fastboot: improve help text tracing/stacktrace: improve help text tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix bootgraph.pl initcall name regexp tracing/fastboot: fix issues and improve output of bootgraph.pl tracepoints: synchronize unregister static inline tracepoints: tracepoint_synchronize_unregister() ftrace: make ftrace_test_p6nop disassembler-friendly markers: fix synchronize marker unregister static inline tracing/fastboot: add better resolution to initcall debug/tracing trace: add build-time check to avoid overrunning hex buffer ftrace: fix hex output mode of ftrace tracing/fastboot: fix initcalls disposition in bootgraph.pl tracing/fastboot: fix printk format typo in boot tracer ftrace: return an error when setting a nonexistent tracer ftrace: make some tracers reentrant ring-buffer: make reentrant ring-buffer: move page indexes into page headers tracing/fastboot: only trace non-module initcalls ftrace: move pc counter in irqtrace ... Manually fix conflicts: - init/main.c: initcall tracing - kernel/module.c: verbose level vs tracepoints - scripts/bootgraph.pl: fallout from cherry-picking commits.
2008-10-20rtc: use bcd2bin/bin2bcdAdrian Bunk
Change various rtc related code to use the new bcd2bin/bin2bcd functions instead of the obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Alessandro Zummo <a.zummo@towertech.it> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (46 commits) UIO: Fix mapping of logical and virtual memory UIO: add automata sercos3 pci card support UIO: Change driver name of uio_pdrv UIO: Add alignment warnings for uio-mem Driver core: add bus_sort_breadthfirst() function NET: convert the phy_device file to use bus_find_device_by_name kobject: Cleanup kobject_rename and !CONFIG_SYSFS kobject: Fix kobject_rename and !CONFIG_SYSFS sysfs: Make dir and name args to sysfs_notify() const platform: add new device registration helper sysfs: use ilookup5() instead of ilookup5_nowait() PNP: create device attributes via default device attributes Driver core: make bus_find_device_by_name() more robust usb: turn dev_warn+WARN_ON combos into dev_WARN debug: use dev_WARN() rather than WARN_ON() in device_pm_add() debug: Introduce a dev_WARN() function sysfs: fix deadlock device model: Do a quickcheck for driver binding before doing an expensive check Driver core: Fix cleanup in device_create_vargs(). Driver core: Clarify device cleanup. ...
2008-10-16gpiolib: request/free hooksDavid Brownell
Add a new internal mechanism to gpiolib to support low power operations by letting gpio_chip instances see when their GPIOs are in use. When no GPIOs are active, chips may be able to enter lower powered runtime states by disabling clocks and/or power domains. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: "Magnus Damm" <magnus.damm@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16gpiolib: gpio_to_irq() hooksDavid Brownell
Add a new gpiolib mechanism: gpio_chip instances can provide mappings between their (input) GPIOs and any associated IRQs. This makes it easier for platforms to support IRQs that are provided by board-specific external chips instead of as part of their core (such as SOC-integrated GPIOs). Also update the irq_to_gpio() description, saying to avoid it because it's not always supported. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16gpio: make gpiochip label constDmitry Baryshkov
Mark gpiochip label as a const char pointer. Fixes things like arch/arm/common/scoop.c: In function `scoop_probe': arch/arm/common/scoop.c:250: warning: assignment discards qualifiers from pointer target type Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16include: replace __FUNCTION__ with __func__Harvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16driver core: basic infrastructure for per-module dynamic debug messagesJason Baron
Base infrastructure to enable per-module debug messages. I've introduced CONFIG_DYNAMIC_PRINTK_DEBUG, which when enabled centralizes control of debugging statements on a per-module basis in one /proc file, currently, <debugfs>/dynamic_printk/modules. When, CONFIG_DYNAMIC_PRINTK_DEBUG, is not set, debugging statements can still be enabled as before, often by defining 'DEBUG' for the proper compilation unit. Thus, this patch set has no affect when CONFIG_DYNAMIC_PRINTK_DEBUG is not set. The infrastructure currently ties into all pr_debug() and dev_dbg() calls. That is, if CONFIG_DYNAMIC_PRINTK_DEBUG is set, all pr_debug() and dev_dbg() calls can be dynamically enabled/disabled on a per-module basis. Future plans include extending this functionality to subsystems, that define their own debug levels and flags. Usage: Dynamic debugging is controlled by the debugfs file, <debugfs>/dynamic_printk/modules. This file contains a list of the modules that can be enabled. The format of the file is as follows: <module_name> <enabled=0/1> . . . <module_name> : Name of the module in which the debug call resides <enabled=0/1> : whether the messages are enabled or not For example: snd_hda_intel enabled=0 fixup enabled=1 driver enabled=0 Enable a module: $echo "set enabled=1 <module_name>" > dynamic_printk/modules Disable a module: $echo "set enabled=0 <module_name>" > dynamic_printk/modules Enable all modules: $echo "set enabled=1 all" > dynamic_printk/modules Disable all modules: $echo "set enabled=0 all" > dynamic_printk/modules Finally, passing "dynamic_printk" at the command line enables debugging for all modules. This mode can be turned off via the above disable command. [gkh: minor cleanups and tweaks to make the build work quietly] Signed-off-by: Jason Baron <jbaron@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-10-14ftrace: create __mcount_loc sectionSteven Rostedt
This patch creates a section in the kernel called "__mcount_loc". This will hold a list of pointers to the mcount relocation for each call site of mcount. For example: objdump -dr init/main.o [...] Disassembly of section .text: 0000000000000000 <do_one_initcall>: 0: 55 push %rbp [...] 000000000000017b <init_post>: 17b: 55 push %rbp 17c: 48 89 e5 mov %rsp,%rbp 17f: 53 push %rbx 180: 48 83 ec 08 sub $0x8,%rsp 184: e8 00 00 00 00 callq 189 <init_post+0xe> 185: R_X86_64_PC32 mcount+0xfffffffffffffffc [...] We will add a section to point to each function call. .section __mcount_loc,"a",@progbits [...] .quad .text + 0x185 [...] The offset to of the mcount call site in init_post is an offset from the start of the section, and not the start of the function init_post. The mcount relocation is at the call site 0x185 from the start of the .text section. .text + 0x185 == init_post + 0xa We need a way to add this __mcount_loc section in a way that we do not lose the relocations after final link. The .text section here will be attached to all other .text sections after final link and the offsets will be meaningless. We need to keep track of where these .text sections are. To do this, we use the start of the first function in the section. do_one_initcall. We can make a tmp.s file with this function as a reference to the start of the .text section. .section __mcount_loc,"a",@progbits [...] .quad do_one_initcall + 0x185 [...] Then we can compile the tmp.s into a tmp.o gcc -c tmp.s -o tmp.o And link it into back into main.o. ld -r main.o tmp.o -o tmp_main.o mv tmp_main.o main.o But we have a problem. What happens if the first function in a section is not exported, and is a static function. The linker will not let the tmp.o use it. This case exists in main.o as well. Disassembly of section .init.text: 0000000000000000 <set_reset_devices>: 0: 55 push %rbp 1: 48 89 e5 mov %rsp,%rbp 4: e8 00 00 00 00 callq 9 <set_reset_devices+0x9> 5: R_X86_64_PC32 mcount+0xfffffffffffffffc The first function in .init.text is a static function. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices The lowercase 't' means that set_reset_devices is local and is not exported. If we simply try to link the tmp.o with the set_reset_devices we end up with two symbols: one local and one global. .section __mcount_loc,"a",@progbits .quad set_reset_devices + 0x10 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices U set_reset_devices We still have an undefined reference to set_reset_devices, and if we try to compile the kernel, we will end up with an undefined reference to set_reset_devices, or even worst, it could be exported someplace else, and then we will have a reference to the wrong location. To handle this case, we make an intermediate step using objcopy. We convert set_reset_devices into a global exported symbol before linking it with tmp.o and set it back afterwards. 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 T set_reset_devices 00000000000000a8 t __setup_set_reset_devices 000000000000105f t __setup_str_set_reset_devices 0000000000000000 t set_reset_devices Now we have a section in main.o called __mcount_loc that we can place somewhere in the kernel using vmlinux.ld.S and access it to convert all these locations that call mcount into nops before starting SMP and thus, eliminating the need to do this with kstop_machine. Note, A well documented perl script (scripts/recordmcount.pl) is used to do all this in one location. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-14tracing: Kernel TracepointsMathieu Desnoyers
Implementation of kernel tracepoints. Inspired from the Linux Kernel Markers. Allows complete typing verification by declaring both tracing statement inline functions and probe registration/unregistration static inline functions within the same macro "DEFINE_TRACE". No format string is required. See the tracepoint Documentation and Samples patches for usage examples. Taken from the documentation patch : "A tracepoint placed in code provides a hook to call a function (probe) that you can provide at runtime. A tracepoint can be "on" (a probe is connected to it) or "off" (no probe is attached). When a tracepoint is "off" it has no effect, except for adding a tiny time penalty (checking a condition for a branch) and space penalty (adding a few bytes for the function call at the end of the instrumented function and adds a data structure in a separate section). When a tracepoint is "on", the function you provide is called each time the tracepoint is executed, in the execution context of the caller. When the function provided ends its execution, it returns to the caller (continuing from the tracepoint site). You can put tracepoints at important locations in the code. They are lightweight hooks that can pass an arbitrary number of parameters, which prototypes are described in a tracepoint declaration placed in a header file." Addition and removal of tracepoints is synchronized by RCU using the scheduler (and preempt_disable) as guarantees to find a quiescent state (this is really RCU "classic"). The update side uses rcu_barrier_sched() with call_rcu_sched() and the read/execute side uses "preempt_disable()/preempt_enable()". We make sure the previous array containing probes, which has been scheduled for deletion by the rcu callback, is indeed freed before we proceed to the next update. It therefore limits the rate of modification of a single tracepoint to one update per RCU period. The objective here is to permit fast batch add/removal of probes on _different_ tracepoints. Changelog : - Use #name ":" #proto as string to identify the tracepoint in the tracepoint table. This will make sure not type mismatch happens due to connexion of a probe with the wrong type to a tracepoint declared with the same name in a different header. - Add tracepoint_entry_free_old. - Change __TO_TRACE to get rid of the 'i' iterator. Masami Hiramatsu <mhiramat@redhat.com> : Tested on x86-64. Performance impact of a tracepoint : same as markers, except that it adds about 70 bytes of instructions in an unlikely branch of each instrumented function (the for loop, the stack setup and the function call). It currently adds a memory read, a test and a conditional branch at the instrumentation site (in the hot path). Immediate values will eventually change this into a load immediate, test and branch, which removes the memory read which will make the i-cache impact smaller (changing the memory read for a load immediate removes 3-4 bytes per site on x86_32 (depending on mov prefixes), or 7-8 bytes on x86_64, it also saves the d-cache hit). About the performance impact of tracepoints (which is comparable to markers), even without immediate values optimizations, tests done by Hideo Aoki on ia64 show no regression. His test case was using hackbench on a kernel where scheduler instrumentation (about 5 events in code scheduler code) was added. Quoting Hideo Aoki about Markers : I evaluated overhead of kernel marker using linux-2.6-sched-fixes git tree, which includes several markers for LTTng, using an ia64 server. While the immediate trace mark feature isn't implemented on ia64, there is no major performance regression. So, I think that we don't have any issues to propose merging marker point patches into Linus's tree from the viewpoint of performance impact. I prepared two kernels to evaluate. The first one was compiled without CONFIG_MARKERS. The second one was enabled CONFIG_MARKERS. I downloaded the original hackbench from the following URL: http://devresources.linux-foundation.org/craiger/hackbench/src/hackbench.c I ran hackbench 5 times in each condition and calculated the average and difference between the kernels. The parameter of hackbench: every 50 from 50 to 800 The number of CPUs of the server: 2, 4, and 8 Below is the results. As you can see, major performance regression wasn't found in any case. Even if number of processes increases, differences between marker-enabled kernel and marker- disabled kernel doesn't increase. Moreover, if number of CPUs increases, the differences doesn't increase either. Curiously, marker-enabled kernel is better than marker-disabled kernel in more than half cases, although I guess it comes from the difference of memory access pattern. * 2 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 4.811 | 4.872 | +0.061 | +1.27 | 100 | 9.854 | 10.309 | +0.454 | +4.61 | 150 | 15.602 | 15.040 | -0.562 | -3.6 | 200 | 20.489 | 20.380 | -0.109 | -0.53 | 250 | 25.798 | 25.652 | -0.146 | -0.56 | 300 | 31.260 | 30.797 | -0.463 | -1.48 | 350 | 36.121 | 35.770 | -0.351 | -0.97 | 400 | 42.288 | 42.102 | -0.186 | -0.44 | 450 | 47.778 | 47.253 | -0.526 | -1.1 | 500 | 51.953 | 52.278 | +0.325 | +0.63 | 550 | 58.401 | 57.700 | -0.701 | -1.2 | 600 | 63.334 | 63.222 | -0.112 | -0.18 | 650 | 68.816 | 68.511 | -0.306 | -0.44 | 700 | 74.667 | 74.088 | -0.579 | -0.78 | 750 | 78.612 | 79.582 | +0.970 | +1.23 | 800 | 85.431 | 85.263 | -0.168 | -0.2 | -------------------------------------------------------------- * 4 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.586 | 2.584 | -0.003 | -0.1 | 100 | 5.254 | 5.283 | +0.030 | +0.56 | 150 | 8.012 | 8.074 | +0.061 | +0.76 | 200 | 11.172 | 11.000 | -0.172 | -1.54 | 250 | 13.917 | 14.036 | +0.119 | +0.86 | 300 | 16.905 | 16.543 | -0.362 | -2.14 | 350 | 19.901 | 20.036 | +0.135 | +0.68 | 400 | 22.908 | 23.094 | +0.186 | +0.81 | 450 | 26.273 | 26.101 | -0.172 | -0.66 | 500 | 29.554 | 29.092 | -0.461 | -1.56 | 550 | 32.377 | 32.274 | -0.103 | -0.32 | 600 | 35.855 | 35.322 | -0.533 | -1.49 | 650 | 39.192 | 38.388 | -0.804 | -2.05 | 700 | 41.744 | 41.719 | -0.025 | -0.06 | 750 | 45.016 | 44.496 | -0.520 | -1.16 | 800 | 48.212 | 47.603 | -0.609 | -1.26 | -------------------------------------------------------------- * 8 CPUs Number of | without | with | diff | diff | processes | Marker [Sec] | Marker [Sec] | [Sec] | [%] | -------------------------------------------------------------- 50 | 2.094 | 2.072 | -0.022 | -1.07 | 100 | 4.162 | 4.273 | +0.111 | +2.66 | 150 | 6.485 | 6.540 | +0.055 | +0.84 | 200 | 8.556 | 8.478 | -0.078 | -0.91 | 250 | 10.458 | 10.258 | -0.200 | -1.91 | 300 | 12.425 | 12.750 | +0.325 | +2.62 | 350 | 14.807 | 14.839 | +0.032 | +0.22 | 400 | 16.801 | 16.959 | +0.158 | +0.94 | 450 | 19.478 | 19.009 | -0.470 | -2.41 | 500 | 21.296 | 21.504 | +0.208 | +0.98 | 550 | 23.842 | 23.979 | +0.137 | +0.57 | 600 | 26.309 | 26.111 | -0.198 | -0.75 | 650 | 28.705 | 28.446 | -0.259 | -0.9 | 700 | 31.233 | 31.394 | +0.161 | +0.52 | 750 | 34.064 | 33.720 | -0.344 | -1.01 | 800 | 36.320 | 36.114 | -0.206 | -0.57 | -------------------------------------------------------------- Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: 'Peter Zijlstra' <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13Merge branch 'master' of ↵David Woodhouse
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 Conflicts: include/asm-x86/statfs.h
2008-10-12Merge branch 'x86/urgent' into core/signalIngo Molnar
Conflicts: arch/x86/kernel/signal_64.c
2008-10-11Merge branch 'x86/unify-cpu-detect' into x86-v28-for-linus-phase4-DIngo Molnar
Conflicts: arch/x86/kernel/cpu/common.c arch/x86/kernel/signal_64.c include/asm-x86/cpufeature.h
2008-09-23signals: demultiplexing SIGTRAP signalSrinivasa Ds
Currently a SIGTRAP can denote any one of below reasons. - Breakpoint hit - H/W debug register hit - Single step - Signal sent through kill() or rasie() Architectures like powerpc/parisc provides infrastructure to demultiplex SIGTRAP signal by passing down the information for receiving SIGTRAP through si_code of siginfot_t structure. Here is an attempt is generalise this infrastructure by extending it to x86 and x86_64 archs. Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com> Cc: Roland McGrath <roland@redhat.com> Cc: akpm@linux-foundation.org Cc: paulus@samba.org Cc: linuxppc-dev@ozlabs.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-16warn: Turn the netdev timeout WARN_ON() into a WARN()Arjan van de Ven
this patch turns the netdev timeout WARN_ON_ONCE() into a WARN_ONCE(), so that the device and driver names are inside the warning message. This helps automated tools like kerneloops.org to collect the data and do statistics, as well as making it more likely that humans cut-n-paste the important message as part of a bugreport. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-10Merge commit 'v2.6.27-rc6' into x86/unify-cpu-detectIngo Molnar
Conflicts: arch/x86/kernel/cpu/amd.c arch/x86/kernel/cpu/common.c arch/x86/kernel/cpu/common_64.c arch/x86/kernel/cpu/feature_names.c include/asm-x86/cpufeature.h Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-09lib: Correct printk %pF to work on all architecturesJames Bottomley
It was introduced by "vsprintf: add support for '%pS' and '%pF' pointer formats" in commit 0fe1ef24f7bd0020f29ffe287dfdb9ead33ca0b2. However, the current way its coded doesn't work on parisc64. For two reasons: 1) parisc isn't in the #ifdef and 2) parisc has a different format for function descriptors Make dereference_function_descriptor() more accommodating by allowing architecture overrides. I put the three overrides (for parisc64, ppc64 and ia64) in arch/kernel/module.c because that's where the kernel internal linker which knows how to deal with function descriptors sits. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Tony Luck <tony.luck@intel.com> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-05tracehook: comment pasto fixesRoland McGrath
Fix some pasto's in comments in the new linux/tracehook.h and asm-generic/syscall.h files. Reported-by: Wenji Huang <wenji.huang@oracle.com> Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-05Fix conditional export of kvh.h and a.out.h to userspace.Khem Raj
Some architectures have moved the asm/ into arch/ and some have not. This patch checks for a.out.h and kvh.h in both places before exporting the corresponding file from linux/ [dwmw2: simplified a little] Signed-off-by: Khem Raj <raj.khem@gmail.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-09-05Merge commit '63cc8c75156462d4b42cbdd76c293b7eee7ddbfe':Ingo Molnar
"percpu: introduce DEFINE_PER_CPU_PAGE_ALIGNED() macro" into x86/core Conflicts: arch/x86/kernel/cpu/common.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-04Make <asm-generic/statfs.h> suitable for 64-bit platforms.David Woodhouse
At the moment, 64-bit platforms (other than Alpha) are all redefining things for themselves instead of using <asm-generic/statfs.h>. As is ARM, since it has special requirements w.r.t. padding. Make <asm-generic/statfs.h> more generic, and they can use it directly. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-08-23rtc: fix deadlockIngo Molnar
if get_rtc_time() is _ever_ called with IRQs off, we deadlock badly in it, waiting for jiffies to increment. So make the code more robust by doing an explicit mdelay(20). This solves a very hard to reproduce/debug hard lockup reported by Mikael Pettersson. Reported-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-12Make ioctl.h compatible with userlandMichael Abbott
The attached patch seems to already exist in a number of branches -- it keeps popping up on Google for me, and is certainly already in Debian -- but is strangely absent from mainstream. The problem appears to be that the patched file ends up as part of the target toolchain, but unfortunately the gcc constant folding doesn't appear to eliminate the __invalid_size_argument_for_IOC value early enough. Certainly compiling C++ programs which use _IO... macros as constants fails without this patch. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-01Missing symbol prefix on vmlinux.lds.hYoshinori Sato
ARCH=h8300: init/main.c:781: undefined reference to `___early_initcall_end' Same problem have __start___bug_table __stop___bug_table __tracedata_start __tracedata_end __per_cpu_start __per_cpu_end When defining a symbol in vmlinux.lds, use the VMLINUX_SYMBOL macro. VMLINUX_SYMBOL adds a prefix charactor. You can't just use straight symbol names in common header files as they dont take into consideration weird arch-specific ABI conventions. in the case of Blackfin/h8300, the ABI dictates that any C-visible symbols have an underscore prefixed to them. Thus all symbols in vmlinux.lds.h need to be wrapped in VMLINUX_SYMBOL() so that each arch can put hide this magic in their own files. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: "Mike Frysinger" <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-28Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (21 commits) x86/PCI: use dev_printk when possible PCI: add D3 power state avoidance quirk PCI: fix bogus "'device' may be used uninitialized" warning in pci_slot PCI: add an option to allow ASPM enabled forcibly PCI: disable ASPM on pre-1.1 PCIe devices PCI: disable ASPM per ACPI FADT setting PCI MSI: Don't disable MSIs if the mask bit isn't supported PCI: handle 64-bit resources better on 32-bit machines PCI: rewrite PCI BAR reading code PCI: document pci_target_state PCI hotplug: fix typo in pcie hotplug output x86 gart: replace to_pages macro with iommu_num_pages x86, AMD IOMMU: replace to_pages macro with iommu_num_pages iommu: add iommu_num_pages helper function dma-coherent: add documentation to new interfaces Cris: convert to using generic dma-coherent mem allocator Sh: use generic per-device coherent dma allocator ARM: support generic per-device coherent dma mem Generic dma-coherent: fix DMA_MEMORY_EXCLUSIVE x86: use generic per-device dma coherent allocator ...
2008-07-28include/asm-generic/pgtable-nopmd.h: macros are noxious, reason #435Andrew Morton
arch/x86/mm/pgtable.c: In function 'pgd_mop_up_pmds': arch/x86/mm/pgtable.c:194: warning: unused variable 'pmd' Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-28gpio: fix build on CONFIG_GPIO_SYSFS=nAtsushi Nemoto
If CONFIG_GENERIC_GPIO=y && CONFIG_GPIO_SYSFS=n, gpio_export() in asm-generic/gpio.h refers -ENOSYS and causes build error. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-29Merge branch 'linus' into core/generic-dma-coherentIngo Molnar
Conflicts: arch/x86/Kconfig Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-nextLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-next: (25 commits) setlocalversion: do not describe if there is nothing to describe kconfig: fix typos: "Suport" -> "Support" kconfig: make defconfig is no longer chatty kconfig: make oldconfig is now less chatty kconfig: speed up all*config + randconfig kconfig: set all new symbols automatically kconfig: add diffconfig utility kbuild: remove Module.markers during mrproper kbuild: sparse needs CF not CHECKFLAGS kernel-doc: handle/strip __init vmlinux.lds: move __attribute__((__cold__)) functions back into final .text section init: fix URL of "The GNU Accounting Utilities" kbuild: add arch/$ARCH/include to search path kbuild: asm symlink support for arch/$ARCH/include kbuild: support arch/$ARCH/include for tags, cscope kbuild: prepare headers_* for arch/$ARCH/include kbuild: install all headers when arch is changed kbuild: make clean removes *.o.* as well kbuild: optimize headers_* targets kbuild: only one call for include/ in make headers_* ...
2008-07-26gpiolib: fix typo in commentMichael Buesch
This fixes an off-by-one error in a comment. Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26tracehook: asm/syscall.hRoland McGrath
This adds asm-generic/syscall.h, which documents what a real asm-ARCH/syscall.h file should define. This is not used yet, but will provide all the machine-dependent details of examining a user system call about to begin, in progress, or just ended. Each arch should add an asm-ARCH/syscall.h that defines all the entry points documented in asm-generic/syscall.h, as short inlines if possible. This lets us write new tracing code that understands user system call registers, without any new arch-specific work. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Reviewed-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26Better interface for hooking early initcallsEduard - Gabriel Munteanu
Added early initcall (pre-SMP) support, using an identical interface to that of regular initcalls. Functions called from do_pre_smp_initcalls() could be converted to use this cleaner interface. This is required by CPU hotplug, because early users have to register notifiers before going SMP. One such CPU hotplug user is the relay interface with buffer-only channels, which needs to register such a notifier, to be usable in early code. This in turn is used by kmemtrace. Signed-off-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: Tom Zanussi <tzanussi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26dma-mapping: add the device argument to dma_mapping_error()FUJITA Tomonori
Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER architecture does: This enables us to cleanly fix the Calgary IOMMU issue that some devices are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423). I think that per-device dma_mapping_ops support would be also helpful for KVM people to support PCI passthrough but Andi thinks that this makes it difficult to support the PCI passthrough (see the above thread). So I CC'ed this to KVM camp. Comments are appreciated. A pointer to dma_mapping_ops to struct dev_archdata is added. If the pointer is non NULL, DMA operations in asm/dma-mapping.h use it. If it's NULL, the system-wide dma_ops pointer is used as before. If it's useful for KVM people, I plan to implement a mechanism to register a hook called when a new pci (or dma capable) device is created (it works with hot plugging). It enables IOMMUs to set up an appropriate dma_mapping_ops per device. The major obstacle is that dma_mapping_error doesn't take a pointer to the device unlike other DMA operations. So x86 can't have dma_mapping_ops per device. Note all the POWER IOMMUs use the same dma_mapping_error function so this is not a problem for POWER but x86 IOMMUs use different dma_mapping_error functions. The first patch adds the device argument to dma_mapping_error. The patch is trivial but large since it touches lots of drivers and dma-mapping.h in all the architecture. This patch: dma_mapping_error() doesn't take a pointer to the device unlike other DMA operations. So we can't have dma_mapping_ops per device. Note that POWER already has dma_mapping_ops per device but all the POWER IOMMUs use the same dma_mapping_error function. x86 IOMMUs use device argument. [akpm@linux-foundation.org: fix sge] [akpm@linux-foundation.org: fix svc_rdma] [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix bnx2x] [akpm@linux-foundation.org: fix s2io] [akpm@linux-foundation.org: fix pasemi_mac] [akpm@linux-foundation.org: fix sdhci] [akpm@linux-foundation.org: build fix] [akpm@linux-foundation.org: fix sparc] [akpm@linux-foundation.org: fix ibmvscsi] Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: Avi Kivity <avi@qumranet.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25vmlinux.lds: move __attribute__((__cold__)) functions back into final .text ↵Jan Beulich
section Due to the addition of __attribute__((__cold__)) to a few symbols without adjusting the linker scripts, those symbols currently may end up outside the [_stext,_etext) range, as they get placed in .text.unlikely by (at least) gcc 4.3.0. This may confuse code not only outside of the kernel, symbol_put_addr()'s BUG() could also trigger. Hence we need to add .text.unlikely (and for future uses of __attribute__((__hot__)) also .text.hot) to the TEXT_TEXT() macro. Issue observed by Lukas Lipavsky. Signed-off-by: Jan Beulich <jbeulich@novell.com> Tested-by: Lukas Lipavsky <llipavsky@suse.cz> Cc: <stable@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-07-25Merge git://git.infradead.org/~dwmw2/random-2.6Linus Torvalds
* git://git.infradead.org/~dwmw2/random-2.6: remove dummy asm/kvm.h files firmware: create firmware binaries during 'make modules'.
2008-07-25remove dummy asm/kvm.h filesAdrian Bunk
This patch removes the dummy asm/kvm.h files on architectures not (yet) supporting KVM and uses the same conditional headers installation as already used for a.out.h . Also removed are superfluous install rules in the s390 and x86 Kbuild files (they are already in Kbuild.asm). Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2008-07-25gpiolib: allow user-selectionMichael Buesch
This patch adds functionality to the gpio-lib subsystem to make it possible to enable the gpio-lib code even if the architecture code didn't request to get it built in. The archtitecture code does still need to implement the gpiolib accessor functions in its asm/gpio.h file. This patch adds the implementations for x86 and PPC. With these changes it is possible to run generic GPIO expansion cards on every architecture that implements the trivial wrapper functions. Support for more architectures can easily be added. Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: David Brownell <david-b@pacbell.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Cc: Samuel Ortiz <sameo@openedhand.com> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25gpio: sysfs interfaceDavid Brownell
This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25printk ratelimiting rewriteDave Young
All ratelimit user use same jiffies and burst params, so some messages (callbacks) will be lost. For example: a call printk_ratelimit(5 * HZ, 1) b call printk_ratelimit(5 * HZ, 1) before the 5*HZ timeout of a, then b will will be supressed. - rewrite __ratelimit, and use a ratelimit_state as parameter. Thanks for hints from andrew. - Add WARN_ON_RATELIMIT, update rcupreempt.h - remove __printk_ratelimit - use __ratelimit in net_ratelimit Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25Add a WARN() macro; this is WARN_ON() + printk argumentsArjan van de Ven
Add a WARN() macro that acts like WARN_ON(), with the added feature that it takes a printk like argument that is printed as part of the warning message. [akpm@linux-foundation.org: fix printk arguments] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25asm-generic/int-ll64.h: always provide __{s,u}64Adrian Bunk
Several compilers offer "long long" without claiming to support C99. Considering how frequent __s64/__u64 are used our userspace headers are anyway unusable without __s64/__u64 available. Always offer __s64/__u64 to non-gcc non-C99 compilers - if they provide "long long" that makes the headers compiling and if they don't they are anyway screwed. Signed-off-by: Adrian Bunk <bunk@kernel.org> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-18Merge branch 'linus' into core/generic-dma-coherentIngo Molnar
Conflicts: kernel/Makefile Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-16Merge branch 'linux-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits) Revert "x86/PCI: ACPI based PCI gap calculation" PCI: remove unnecessary volatile in PCIe hotplug struct controller x86/PCI: ACPI based PCI gap calculation PCI: include linux/pm_wakeup.h for device_set_wakeup_capable PCI PM: Fix pci_prepare_to_sleep x86/PCI: Fix PCI config space for domains > 0 Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n PCI: Simplify PCI device PM code PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep PCI ACPI: Rework PCI handling of wake-up ACPI: Introduce new device wakeup flag 'prepared' ACPI: Introduce acpi_device_sleep_wake function PCI: rework pci_set_power_state function to call platform first PCI: Introduce platform_pci_power_manageable function ACPI: Introduce acpi_bus_power_manageable function PCI: make pci_name use dev_name PCI: handle pci_name() being const PCI: add stub for pci_set_consistent_dma_mask() PCI: remove unused arch pcibios_update_resource() functions PCI: fix pci_setup_device()'s sprinting into a const buffer ... Fixed up conflicts in various files (arch/x86/kernel/setup_64.c, arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c, drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86 and ACPI updates manually.
2008-07-15mm: fix build on non-mmu machinesSebastian Siewior
Commit 1ea0704e0d aka "mm: add a ptep_modify_prot transaction abstraction" caused: | CC init/main.o |In file included from include2/asm/pgtable.h:68, | from /home/bigeasy/git/linux-2.6-m68k/include/linux/mm.h:39, | from include2/asm/uaccess.h:8, | from /home/bigeasy/git/linux-2.6-m68k/include/linux/poll.h:13, | from /home/bigeasy/git/linux-2.6-m68k/include/linux/rtc.h:113, | from /home/bigeasy/git/linux-2.6-m68k/include/linux/efi.h:19, | from /home/bigeasy/git/linux-2.6-m68k/init/main.c:43: |/linux-2.6/include/asm-generic/pgtable.h: In function '__ptep_modify_prot_start': |/linux-2.6/include/asm-generic/pgtable.h:209: error: implicit declaration of function 'ptep_get_and_clear' |/linux-2.6/include/asm-generic/pgtable.h:209: error: incompatible types in return |/linux-2.6/include/asm-generic/pgtable.h: In function '__ptep_modify_prot_commit': |/linux-2.6/include/asm-generic/pgtable.h:220: error: implicit declaration of function 'set_pte_at' |make[2]: *** [init/main.o] Error 1 |make[1]: *** [init] Error 2 |make: *** [sub-make] Error 2 on my m68knommu box. Acked-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Hugh Dickins <hugh@veritas.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>