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* x86: Fix ASM_X86__ header guardsH. Peter Anvin2008-10-22271-805/+805
| | | | | | | | | Change header guards named "ASM_X86__*" to "_ASM_X86_*" since: a. the double underscore is ugly and pointless. b. no leading underscore violates namespace constraints. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of uml-config.hAl Viro2008-10-223-16/+17
| | | | | | | Take a few symbols we need into kern_constants.h Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of arch/um/Kconfig.archAl Viro2008-10-225-132/+131
| | | | | | | | | | Teach scripts/kconfig/Makefile and top-level Makefile that arch/*/Makefile is allowed to say Kconfig := <whatever I want instead of arch/blah/Kconfig>. Rewrite arch/um/Kconfig and arch/um/Kconfig.<subarch> so that the latter would be top-level one (and include the pieces of the former). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of arch/um/os symlinkAl Viro2008-10-225-25/+4
| | | | | | | | we can get DEV_NULL defined for arch/um/drivers/null.c in less convoluted ways, TYVM... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of excessive includes of uml-config.hAl Viro2008-10-229-9/+0
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of header symlinksAl Viro2008-10-2250-19/+5
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: merge Kconfig.i386 and Kconfig.x86_64Al Viro2008-10-224-57/+23
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of sysdep symlinkAl Viro2008-10-2241-10/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: trim the junk from uml ptrace-*.hAl Viro2008-10-222-15/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: take vm-flags.h to sysdepAl Viro2008-10-224-3/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of uml asm/archAl Viro2008-10-222-18/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of uml highmem.hAl Viro2008-10-224-17/+14
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of uml unistd.hAl Viro2008-10-225-41/+4
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of system.h -> system.h includeAl Viro2008-10-227-55/+266
| | | | | | | | Long-term we want to split system.h and include barriers part from underlying target; for now copy that part to sysdep. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: uml atomic.h is not needed anymoreAl Viro2008-10-221-11/+0
| | | | | | | | Its only difference from underlying atomic.h used to be the include of kernel.h; it's not needed there anymore. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: untangle uml ldt.hAl Viro2008-10-229-9/+9
| | | | | | | | | * turn asm/ldt.h into ldt.h; update the (very few) users * take host_ldt.h into sysdep, kill symlink mess * includes of asm/arch/ldt.h turn into asm/ldt.h now Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of more uml asm/arch usesAl Viro2008-10-223-3/+3
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: remove dead header (uml module-generic.h; never used these days)Al Viro2008-10-221-6/+0
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: get rid of uml signal.hAl Viro2008-10-223-30/+2
| | | | | | | | | the only theoretical reason for it these days is ppc; aside of uml/ppc being dead, do_signal() would be happier in arch/powerpc/kernel/signal.h anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: sanitize uml sigcontext.h usesAl Viro2008-10-227-71/+2
| | | | | | | | | | | | a) the only difference between sigcontext and sysdep/sigcontext is that the former contains externs for two long-dead functions. Removed, switched the only user to sysdep/sigcontext b) asm/sigcontext.h is removable - that of underlying architecture would get used. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: now we can get rid of trivial uml headersAl Viro2008-10-2260-371/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: ... and asm-x86 moveAl Viro2008-10-22338-9/+38681
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: initial part of asm-um moveAl Viro2008-10-22145-8/+3699
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* x86, um: take arch/um/include/* out of the wayAl Viro2008-10-2279-27/+26
| | | | | | | | | We can't just plop asm/* into it - userland helpers are built with it in search path and seeing asm/* show up there suddenly would be a bad idea. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* misc: replace remaining __FUNCTION__ with __func__Harvey Harrison2008-10-203-5/+5
| | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6Linus Torvalds2008-10-20133-287/+12211
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6: parisc: convert to generic compat_sys_ptrace parisc: add rtc platform driver parisc: initialize unwinder much earlier parisc: add new syscalls parisc: hijack jump to start_kernel parisc: add pdc_coproc_cfg_unlocked and set_firmware_width_unlocked parisc: move include/asm-parisc to arch/parisc/include/asm parisc: move pdc_result to real2.S parisc: unify CCIO_COLLECT_STATS implementation parisc: add arch/parisc/kernel/.gitignore parisc: ropes.h - fix <asm-parisc/*> -> <asm/*> parisc: parisc-agp - fix <asm-parisc/*> -> <asm/*> Resolve remove/rename conflict: include/asm-parisc/a.out.h is no longer relevant.
| * parisc: convert to generic compat_sys_ptraceHelge Deller2008-10-173-258/+183
| | | | | | | | | | | | | | | | | | This patch does the compat_sys_ptrace conversion for parisc. In addition it does convert the parisc ptrace code to use the architecture-independent ptrace infrastructure instead of own coding. Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
| * parisc: add rtc platform driverKyle McMartin2008-10-102-1/+21
| | | | | | | | Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
| * parisc: initialize unwinder much earlierJames Bottomley2008-10-103-3/+5
| | | | | | | | | | | | | | | | | | | | The unwinder was being initialized way too late to be any use debugging early boot crashes. Instead of relying on module_init initcalls to initialize it, let's do it explicitly as early as we can. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
| * parisc: add new syscallsKyle McMartin2008-10-102-2/+14
| | | | | | | | Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
| * parisc: hijack jump to start_kernelKyle McMartin2008-10-102-2/+27
| | | | | | | | | | | | | | | | | | | | | | | | Bang in our own start_parisc call, which initializes the PDC width, and turns on the FPU. Previously, if CONFIG_PRINTK_TIME was on, we'd attempt to use the FPU before we had enabled it, resulting in a difficult to diagnose panic. This patch causes init_per_cpu to redundantly set these for cpu0, but this is harmless.
| * parisc: add pdc_coproc_cfg_unlocked and set_firmware_width_unlockedKyle McMartin2008-10-102-21/+46
| | | | | | | | | | | | | | These functions are called only when bringing up the monarch cpu, so it is safe to call them without taking the pdc spinlock. In the future, this may become relevant for lockdep, since these functions were taking spinlocks before start_kernel called the lockdep initializers.
| * parisc: move include/asm-parisc to arch/parisc/include/asmKyle McMartin2008-10-10123-0/+11977
| |
| * parisc: move pdc_result to real2.SKyle McMartin2008-10-103-2/+17
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| * parisc: add arch/parisc/kernel/.gitignoreKyle McMartin2008-10-101-0/+1
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* | Merge branch 'linux-next' of ↵Linus Torvalds2008-10-206-18/+174
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: (41 commits) PCI: fix pci_ioremap_bar() on s390 PCI: fix AER capability check PCI: use pci_find_ext_capability everywhere PCI: remove #ifdef DEBUG around dev_dbg call PCI hotplug: fix get_##name return value problem PCI: document the pcie_aspm kernel parameter PCI: introduce an pci_ioremap(pdev, barnr) function powerpc/PCI: Add legacy PCI access via sysfs PCI: Add ability to mmap legacy_io on some platforms PCI: probing debug message uniformization PCI: support PCIe ARI capability PCI: centralize the capabilities code in probe.c PCI: centralize the capabilities code in pci-sysfs.c PCI: fix 64-vbit prefetchable memory resource BARs PCI: replace cfg space size (256/4096) by macros. PCI: use resource_size() everywhere. PCI: use same arg names in PCI_VDEVICE comment PCI hotplug: rpaphp: make debug var unique PCI: use %pF instead of print_fn_descriptor_symbol() in quirks.c PCI: fix hotplug get_##name return value problem ...
| * | powerpc/PCI: Add legacy PCI access via sysfsBenjamin Herrenschmidt2008-10-203-1/+153
| | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for legacy_io and legacy_mem files in bus class directories in sysfs for powerpc Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
| * | PCI: Add ability to mmap legacy_io on some platformsBenjamin Herrenschmidt2008-10-202-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the ability to mmap legacy IO space to the legacy_io files in sysfs on platforms that support it. This will allow to clean up X to use this instead of /dev/mem for legacy IO accesses such as those performed by Int10. While at it I moved pci_create/remove_legacy_files() to pci-sysfs.c where I think they belong, thus making more things statis in there and cleaned up some spurrious prototypes in the ia64 pci.h file Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
| * | x86/PCI: irq and pci_ids patch for Intel Ibex Peak DeviceIDsSeth Heasley2008-10-201-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates the Intel Ibex Peak (PCH) LPC and SMBus Controller DeviceIDs. The LPC Controller ID is set by Firmware within the range of 0x3b00-3b1f. This range is included in pci_ids.h using min and max values, and irq.c now has code to handle the range (in lieu of 32 additions to a SWITCH statement). The SMBus Controller ID is a fixed-value and will not change. Signed-off-by: Seth Heasley <seth.heasley@intel.com> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
| * | x86/PCI: follow lspci device/vendor styleBjorn Helgaas2008-10-201-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | Use "[%04x:%04x]" for PCI vendor/device IDs to follow the format used by lspci(8). Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* | | Merge branch 'tracing-v28-for-linus' of ↵Linus Torvalds2008-10-209-192/+197
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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.
| * | | ftrace: make ftrace_test_p6nop disassembler-friendlyAnders Kaseorg2008-10-141-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 4c3dc21b136f8cb4b72afee16c3ba7e961656c0b in tip introduced the 5-byte NOP ftrace_test_p6nop: jmp . + 5 .byte 0x00, 0x00, 0x00 This is not friendly to disassemblers because an odd number of 0x00s ends in the middle of an instruction boundary. This changes the 0x00s to 1-byte NOPs (0x90). Signed-off-by: Anders Kaseorg <andersk@mit.edu> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sputrace: use marker_synchronize_unregister()Mathieu Desnoyers2008-10-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We need a marker_synchronize_unregister() before the end of exit() to make sure every probe callers have exited the non preemptible section and thus are not executing the probe code anymore. Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Acked-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86/ftrace: use uaccess in atomic contextFrédéric Weisbecker2008-10-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With latest -tip I get this bug: [ 49.439988] in_atomic():0, irqs_disabled():1 [ 49.440118] INFO: lockdep is turned off. [ 49.440118] Pid: 2814, comm: modprobe Tainted: G W 2.6.27-rc7 #4 [ 49.440118] [<c01215e1>] __might_sleep+0xe1/0x120 [ 49.440118] [<c01148ea>] ftrace_modify_code+0x2a/0xd0 [ 49.440118] [<c01148a2>] ? ftrace_test_p6nop+0x0/0xa [ 49.440118] [<c016e80e>] __ftrace_update_code+0xfe/0x2f0 [ 49.440118] [<c01148a2>] ? ftrace_test_p6nop+0x0/0xa [ 49.440118] [<c016f190>] ftrace_convert_nops+0x50/0x80 [ 49.440118] [<c016f1d6>] ftrace_init_module+0x16/0x20 [ 49.440118] [<c015498b>] load_module+0x185b/0x1d30 [ 49.440118] [<c01767a0>] ? find_get_page+0x0/0xf0 [ 49.440118] [<c02463c0>] ? sprintf+0x0/0x30 [ 49.440118] [<c034e012>] ? mutex_lock_interruptible_nested+0x1f2/0x350 [ 49.440118] [<c0154eb3>] sys_init_module+0x53/0x1b0 [ 49.440118] [<c0352340>] ? do_page_fault+0x0/0x740 [ 49.440118] [<c0104012>] syscall_call+0x7/0xb [ 49.440118] ======================= It is because ftrace_modify_code() calls copy_to_user and copy_from_user. These functions have been inserted after guessing that there couldn't be any race condition but copy_[to/from]_user might sleep and __ftrace_update_code is called with local_irq_saved. These function have been inserted since this commit: d5e92e8978fd2574e415dc2792c5eb592978243d: "ftrace: x86 use copy from user function" Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86: suppress trivial sparse signedness warningsHarvey Harrison2008-10-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Could just as easily change the three casts to cast to the correct type...this patch changes the type of ftrace_nop instead. Supresses sparse warnings: arch/x86/kernel/ftrace.c:157:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:157:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:157:14: got unsigned long *<noident> arch/x86/kernel/ftrace.c:161:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:161:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:161:14: got unsigned long *<noident> arch/x86/kernel/ftrace.c:165:14: warning: incorrect type in assignment (different signedness) arch/x86/kernel/ftrace.c:165:14: expected long *static [toplevel] ftrace_nop arch/x86/kernel/ftrace.c:165:14: got unsigned long *<noident> Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | mmiotrace: remove left-over marker cruftPekka Paalanen2008-10-141-64/+0
| | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Pekka Paalanen <pq@iki.fi> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86 mmiotrace: implement mmiotrace_printk()Pekka Paalanen2008-10-142-1/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Offer mmiotrace users a function to inject markers from inside the kernel. This depends on the trace_vprintk() patch. Signed-off-by: Pekka Paalanen <pq@iki.fi> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86 mmiotrace: fix a rare memory leakPekka Paalanen2008-10-141-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Pekka Paalanen <pq@iki.fi> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | ftrace: x86 use copy to and from user functionsSteven Rostedt2008-10-141-25/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The modification of code is performed either by kstop_machine, before SMP starts, or on module code before the module is executed. There is no reason to do the modifications from assembly. The copy to and from user functions are sufficient and produces cleaner and easier to read code. Thanks to Benjamin Herrenschmidt for suggesting the idea. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | ftrace: use only 5 byte nops for x86Steven Rostedt2008-10-141-7/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mathieu Desnoyers revealed a bug in the original code. The nop that is used to relpace the mcount caller can be a two part nop. This runs the risk where a process can be preempted after executing the first nop, but before the second part of the nop. The ftrace code calls kstop_machine to keep multiple CPUs from executing code that is being modified, but it does not protect against a task preempting in the middle of a two part nop. If the above preemption happens and the tracer is enabled, after the kstop_machine runs, all those nops will be calls to the trace function. If the preempted process that was preempted between the two nops is executed again, it will execute half of the call to the trace function, and this might crash the system. This patch instead uses what both the latest Intel and AMD spec suggests. That is the P6_NOP5 sequence of "0x0f 0x1f 0x44 0x00 0x00". Note, some older CPUs and QEMU might fault on this nop, so this nop is executed with fault handling first. If it detects a fault, it will then use the code "0x66 0x66 0x66 0x66 0x90". If that faults, it will then default to a simple "jmp 1f; .byte 0x00 0x00 0x00; 1:". The jmp is not optimal but will do if the first two can not be executed. TODO: Examine the cpuid to determine the nop to use. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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