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* perf/x86: Enable raw event access to Intel offcore eventsPeter Zijlstra2011-11-141-5/+1
| | | | | | | | | | | | | | | | | | Now that the core offcore support is fixed up (thanks Stephane) and we have sane generic events utilizing them, re-enable the raw access to the feature as well. Note that it doesn't matter if you use event 0x1b7 or 0x1bb to specify an offcore event, either one works and neither guarantees you'll end up on a particular offcore MSR. Based on original patch from: Vince Weaver <vweaver1@eecs.utk.edu>. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Vince Weaver <vweaver1@eecs.utk.edu>. Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1108031200390.703@cl320.eecs.utk.edu Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf: Don't use -ENOSPC for out of PMU resourcesPeter Zijlstra2011-11-142-6/+6
| | | | | | | | | | | | | | | | People (Linus) objected to using -ENOSPC to signal not having enough resources on the PMU to satisfy the request. Use -EINVAL. Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Stephane Eranian <eranian@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Deng-Cheng Zhu <dengcheng.zhu@gmail.com> Cc: David Daney <david.daney@cavium.com> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-xv8geaz2zpbjhlx0svmpp28n@git.kernel.org [ merged to newer kernel, fixed up MIPS impact ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* perf/x86: Fix PEBS instruction unwindPeter Zijlstra2011-11-141-1/+5
| | | | | | | | | | | | | | Masami spotted that we always try to decode the instruction stream as 64bit instructions when running a 64bit kernel, this doesn't work for ia32-compat proglets. Use TIF_IA32 to detect if we need to use the 32bit instruction decoder. Reported-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: stable@kernel.org Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds2011-11-065-0/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
| * x86: Fix files explicitly requiring export.h for EXPORT_SYMBOL/THIS_MODULEPaul Gortmaker2011-10-315-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These files were implicitly getting EXPORT_SYMBOL via device.h which was including module.h, but that will be fixed up shortly. By fixing these now, we can avoid seeing things like: arch/x86/kernel/rtc.c:29: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ arch/x86/kernel/pci-dma.c:20: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL’ arch/x86/kernel/e820.c:69: warning: type defaults to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’ [ with input from Randy Dunlap <rdunlap@xenotime.net> and also from Stephen Rothwell <sfr@canb.auug.org.au> ] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | Merge branch 'linux_next' of ↵Linus Torvalds2011-11-021-12/+6
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac * 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac: (21 commits) MAINTAINERS: add an entry for Edac Sandy Bridge driver edac: tag sb_edac as EXPERIMENTAL, as it requires more testing EDAC: Fix incorrect edac mode reporting in sb_edac edac: sb_edac: Add it to the building system edac: Add an experimental new driver to support Sandy Bridge CPU's i7300_edac: Fix error cleanup logic i7core_edac: Initialize memory name with cpu, channel, bank i7core_edac: Fix compilation on 32 bits arch i7core_edac: scrubbing fixups EDAC: Correct Kconfig dependencies i7core_edac: return -ENODEV if no MC is found i7core_edac: use edac's own way to print errors MAINTAINERS: remove dropped edac_mce.* from the file i7core_edac: Drop the edac_mce facility x86, MCE: Use notifier chain only for MCE decoding EDAC i7core: Use mce socketid for better compatibility i7core_edac: Don't enable memory scrubbing for Xeon 35xx i7core_edac: Add scrubbing support edac: Move edac main structs to include/linux/edac.h i7core_edac: Fix oops when trying to inject errors ...
| * i7core_edac: Drop the edac_mce facilityBorislav Petkov2011-11-011-1/+0
| | | | | | | | | | | | | | | | Remove edac_mce pieces and use the normal MCE decoder notifier chain by retaining the same functionality with considerably less code. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| * x86, MCE: Use notifier chain only for MCE decodingBorislav Petkov2011-10-311-11/+6
| | | | | | | | | | | | | | | | | | | | Drop the edac_mce custom hook in favor of the generic notifier mechanism. Also, do not log the error to mcelog if the notified agent was able to decode it. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
* | Merge branch 'x86-rdrand-for-linus' of ↵Linus Torvalds2011-10-283-0/+76
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-rdrand-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, random: Verify RDRAND functionality and allow it to be disabled x86, random: Architectural inlines to get random integers with RDRAND random: Add support for architectural random hooks Fix up trivial conflicts in drivers/char/random.c: the architectural random hooks touched "get_random_int()" that was simplified to use MD5 and not do the keyptr thing any more (see commit 6e5714eaf77d: "net: Compute protocol sequence numbers and fragment IDs using MD5").
| * | x86, random: Verify RDRAND functionality and allow it to be disabledH. Peter Anvin2011-07-313-0/+76
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If the CPU declares that RDRAND is available, go through a guranteed reseed sequence, and make sure that it is actually working (producing data.) If it does not, disable the CPU feature flag. Allow RDRAND to be disabled on the command line (as opposed to at compile time) for a user who has special requirements with regards to random numbers. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Matt Mackall <mpm@selenic.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "Theodore Ts'o" <tytso@mit.edu>
* | | Merge branch 'x86-microcode-for-linus' of ↵Linus Torvalds2011-10-284-13/+26
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, microcode, AMD: Add microcode revision to /proc/cpuinfo x86, microcode: Correct microcode revision format coretemp: Get microcode revision from cpu_data x86, intel: Use c->microcode for Atom errata check x86, intel: Output microcode revision in /proc/cpuinfo x86, microcode: Don't request microcode from userspace unnecessarily Fix up trivial conflicts in arch/x86/kernel/cpu/amd.c (conflict between moving AMD BSP code to cpu_dev helper function and adding AMD microcode revision to /proc/cpuinfo code)
| * | | x86, microcode, AMD: Add microcode revision to /proc/cpuinfoBorislav Petkov2011-10-191-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable microcode revision output for AMD after 506ed6b53e00 ("x86, intel: Output microcode revision in /proc/cpuinfo") did it for Intel. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
| * | | x86, microcode: Correct microcode revision formatBorislav Petkov2011-10-192-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 506ed6b53e00 ("x86, intel: Output microcode revision in /proc/cpuinfo") added microcode revision format to /proc/cpuinfo and the MCE handler in decimal format but both AMD and Intel patch levels are handled as hex numbers. Fix it. Acked-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
| * | | x86, intel: Use c->microcode for Atom errata checkAndi Kleen2011-10-141-11/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that the cpu update level is available the Atom PSE errata check can use it directly without reading the MSR again. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1318466795-7393-2-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86, intel: Output microcode revision in /proc/cpuinfoAndi Kleen2011-10-143-2/+18
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I got a request to make it easier to determine the microcode update level on Intel CPUs. This patch adds a new "microcode" field to /proc/cpuinfo. The microcode level is also outputed on fatal machine checks together with the other CPUID model information. I removed the respective code from the microcode update driver, it just reads the field from cpu_data. Also when the microcode is updated it fills in the new values too. I had to add a memory barrier to native_cpuid to prevent it being optimized away when the result is not used. This turns out to clean up further code which already got this information manually. This is done in followon patches. Signed-off-by: Andi Kleen <ak@linux.intel.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1318466795-7393-1-git-send-email-andi@firstfloor.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | Merge branch 'x86-hyperv-for-linus' of ↵Linus Torvalds2011-10-281-0/+23
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-hyperv-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Hyper-V: Integrate the clocksource with Hyper-V detection code Fix up conflicts in drivers/staging/hv/Makefile manually (some of the hv code has moved out of staging to drivers/hv/)
| * | | x86: Hyper-V: Integrate the clocksource with Hyper-V detection codeK. Y. Srinivasan2011-09-081-0/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Hyper-V clocksource driver is best integrated with Hyper-V detection code since: (a) Linux guests running on Hyper-V require it (b) Integration into that code significanly reduces code size Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com> Cc: gregkh@suse.de Cc: devel@linuxdriverproject.org Cc: virtualization@lists.osdl.org Link: http://lkml.kernel.org/r/1315434310-4827-1-git-send-email-kys@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds2011-10-284-97/+81
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, amd: Include linux/elf.h since we use stuff from asm/elf.h x86: cache_info: Update calculation of AMD L3 cache indices x86: cache_info: Kill the atomic allocation in amd_init_l3_cache() x86: cache_info: Kill the moronic shadow struct x86: cache_info: Remove bogus free of amd_l3_cache data x86, amd: Include elf.h explicitly, prepare the code for the module.h split x86-32, amd: Move va_align definition to unbreak 32-bit build x86, amd: Move BSP code to cpu_dev helper x86: Add a BSP cpu_dev helper x86, amd: Avoid cache aliasing penalties on AMD family 15h
| * | | | x86: cache_info: Update calculation of AMD L3 cache indicesFrank Arnold2011-09-121-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | L3 subcaches 0 and 1 of AMD Family 15h CPUs can have a size of 2MB. Update the calculation routine for the number of L3 indices to reflect that. Signed-off-by: Frank Arnold <frank.arnold@amd.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Rosenfeld Hans <Hans.Rosenfeld@amd.com> Cc: Herrmann3 Andreas <Andreas.Herrmann3@amd.com> Cc: Mike Travis <travis@sgi.com> Cc: Frank Arnold <Frank.Arnold@amd.com> Link: http://lkml.kernel.org/r/20110726170449.GB32536@aftab Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: cache_info: Kill the atomic allocation in amd_init_l3_cache()Thomas Gleixner2011-09-121-48/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It's not a good reason to allocate memory in the smp function call just because someone thought it's the most conveniant place. The AMD L3 data is coupled to the northbridge info by a pointer to the corresponding north bridge data. So allocating it with the northbridge data and referencing the northbridge in the cache_info code instead uses less memory and gets rid of that atomic allocation hack in the smp function call. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <borislav.petkov@amd.com> Cc: Hans Rosenfeld <hans.rosenfeld@amd.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mike Travis <travis@sgi.com> Link: http://lkml.kernel.org/r/20110723212626.688229918@linutronix.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: cache_info: Kill the moronic shadow structThomas Gleixner2011-09-121-38/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit f9b90566c ("x86: reduce stack usage in init_intel_cacheinfo") introduced a shadow structure to reduce the stack usage on large machines instead of making the smaller structure embedded into the large one. That's definitely a candidate for the bad taste award. Move the small struct into the large one and get rid of the ugly type casts. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Hans Rosenfeld <hans.rosenfeld@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mike Travis <travis@sgi.com> Link: http://lkml.kernel.org/r/20110723212626.625651773@linutronix.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86: cache_info: Remove bogus free of amd_l3_cache dataThomas Gleixner2011-09-121-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | free_cache_attributes() kfree's: per_cpu(ici_cpuid4_info, cpu)->l3 which is a pointer to memory which was allocated as a block in amd_init_l3_cache(). l3 of a particular cpu points to a part of this memory blob. The part and the rest of the blob are still referenced by other cpus. As far as I can tell from the git history this is a leftover from the conversion from per cpu to node data with commit ba06edb63(x86, cacheinfo: Make L3 cache info per node) and the following commit f658bcfb2(x86, cacheinfo: Cleanup L3 cache index disable support) Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Hans Rosenfeld <hans.rosenfeld@amd.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Mike Travis <travis@sgi.com> Link: http://lkml.kernel.org/r/20110723212626.550539989@linutronix.de Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86, amd: Include elf.h explicitly, prepare the code for the module.h splitStephen Rothwell2011-08-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the moduleu.h splitting tree is merged to the latest tip:x86/cpu tree, the x86_64 allmodconfig build fails like this: arch/x86/kernel/cpu/amd.c: In function 'bsp_init_amd': arch/x86/kernel/cpu/amd.c:437:3: error: 'va_align' undeclared (first use in this function) arch/x86/kernel/cpu/amd.c:438:23: error: 'ALIGN_VA_32' undeclared (first use in this function) arch/x86/kernel/cpu/amd.c:438:37: error: 'ALIGN_VA_64' undeclared (first use in this function) This is caused by the module.h split up intreacting with commit dfb09f9b7ab0 ("x86, amd: Avoid cache aliasing penalties on AMD family 15h") from the tip:x86/cpu tree. I have added the following patch for today (this, or something similar, could be applied to the tip tree directly - the export.h include below was added by the module.h splitup). So include elf.h to use va_align and remove this implicit dependency on module.h doing it for us. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Link: http://lkml.kernel.org/r/20110810114956.238d66772883636e3040d29f@canb.auug.org.au Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | x86, amd: Move BSP code to cpu_dev helperBorislav Petkov2011-08-051-30/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move code which is run once on the BSP during boot into the cpu_dev helper. [ hpa: removed bogus cpu_has -> static_cpu_has conversion ] Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/20110805180409.GC26217@aftab Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | | | x86: Add a BSP cpu_dev helperBorislav Petkov2011-08-052-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a function ptr to struct cpu_dev which is destined to be run only once on the BSP during boot. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/20110805180116.GB26217@aftab Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | | | x86, amd: Avoid cache aliasing penalties on AMD family 15hBorislav Petkov2011-08-051-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch provides performance tuning for the "Bulldozer" CPU. With its shared instruction cache there is a chance of generating an excessive number of cache cross-invalidates when running specific workloads on the cores of a compute module. This excessive amount of cross-invalidations can be observed if cache lines backed by shared physical memory alias in bits [14:12] of their virtual addresses, as those bits are used for the index generation. This patch addresses the issue by clearing all the bits in the [14:12] slice of the file mapping's virtual address at generation time, thus forcing those bits the same for all mappings of a single shared library across processes and, in doing so, avoids instruction cache aliases. It also adds the command line option "align_va_addr=(32|64|on|off)" with which virtual address alignment can be enabled for 32-bit or 64-bit x86 individually, or both, or be completely disabled. This change leaves virtual region address allocation on other families and/or vendors unaffected. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1312550110-24160-2-git-send-email-bp@amd64.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | | | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2011-10-2612-553/+1048
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (121 commits) perf symbols: Increase symbol KSYM_NAME_LEN size perf hists browser: Refuse 'a' hotkey on non symbolic views perf ui browser: Use libslang to read keys perf tools: Fix tracing info recording perf hists browser: Elide DSO column when it is set to just one DSO, ditto for threads perf hists: Don't consider filtered entries when calculating column widths perf hists: Don't decay total_period for filtered entries perf hists browser: Honour symbol_conf.show_{nr_samples,total_period} perf hists browser: Do not exit on tab key with single event perf annotate browser: Don't change selection line when returning from callq perf tools: handle endianness of feature bitmap perf tools: Add prelink suggestion to dso update message perf script: Fix unknown feature comment perf hists browser: Apply the dso and thread filters when merging new batches perf hists: Move the dso and thread filters from hist_browser perf ui browser: Honour the xterm colors perf top tui: Give color hints just on the percentage, like on --stdio perf ui browser: Make the colors configurable and change the defaults perf tui: Remove unneeded call to newtCls on startup perf hists: Don't format the percentage on hist_entry__snprintf ... Fix up conflicts in arch/x86/kernel/kprobes.c manually. Ingo's tree did the insane "add volatile to const array", which just doesn't make sense ("volatile const"?). But we could remove the const *and* make the array volatile to make doubly sure that gcc doesn't optimize it away.. Also fix up kernel/trace/ring_buffer.c non-data-conflicts manually: the reader_lock has been turned into a raw lock by the core locking merge, and there was a new user of it introduced in this perf core merge. Make sure that new use also uses the raw accessor functions.
| * | | | | perf, x86: Implement IBS initializationRobert Richter2011-10-102-1/+295
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch implements IBS feature detection and initialzation. The code is shared between perf and oprofile. If IBS is available on the system for perf, a pmu is setup. Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1316597423-25723-3-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | perf, x86: Share IBS macros between perf and oprofileRobert Richter2011-10-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Moving IBS macros from oprofile to <asm/perf_event.h> to make it available to perf. No additional changes. Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1316597423-25723-2-git-send-email-robert.richter@amd.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | x86, nmi: Wire up NMI handlers to new routinesDon Zickus2011-10-103-81/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Just convert all the files that have an nmi handler to the new routines. Most of it is straight forward conversion. A couple of places needed some tweaking like kgdb which separates the debug notifier from the nmi handler and mce removes a call to notify_die. [Thanks to Ying for finding out the history behind that mce call https://lkml.org/lkml/2010/5/27/114 And Boris responding that he would like to remove that call because of it https://lkml.org/lkml/2011/9/21/163] The things that get converted are the registeration/unregistration routines and the nmi handler itself has its args changed along with code removal to check which list it is on (most are on one NMI list except for kgdb which has both an NMI routine and an NMI Unknown routine). Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Corey Minyard <minyard@acm.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Robert Richter <robert.richter@amd.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Corey Minyard <minyard@acm.org> Cc: Jack Steiner <steiner@sgi.com> Link: http://lkml.kernel.org/r/1317409584-23662-4-git-send-email-dzickus@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | perf, intel: Use GO/HO bits in perf-ctrGleb Natapov2011-10-102-3/+100
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel does not have guest/host-only bit in perf counters like AMD does. To support GO/HO bits KVM needs to switch EVENTSELn values (or PERF_GLOBAL_CTRL if available) at a guest entry. If a counter is configured to count only in a guest mode it stays disabled in a host, but VMX is configured to switch it to enabled value during guest entry. This patch adds GO/HO tracking to Intel perf code and provides interface for KVM to get a list of MSRs that need to be switched on a guest entry. Only cpus with architectural PMU (v1 or later) are supported with this patch. To my knowledge there is not p6 models with VMX but without architectural PMU and p4 with VMX are rare and the interface is general enough to support them if need arise. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317816084-18026-7-git-send-email-gleb@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | perf, amd: Use GO/HO bits in perf-ctrJoerg Roedel2011-10-061-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The AMD perf-counters support counting in guest or host-mode only. Make use of that feature when user-space specified guest/host-mode only counting. Signed-off-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1317816084-18026-3-git-send-email-gleb@redhat.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | Merge branch 'ras' of git://amd64.org/linux/bp into perf/coreIngo Molnar2011-10-061-6/+14
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| | * | | | | x86, mce: Do not call del_timer_sync() in IRQ contextHidetoshi Seto2011-09-141-6/+14
| | | |_|/ / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | del_timer_sync() can cause a deadlock when called in interrupt context. It is used with on_each_cpu() in some parts for sysfs files like bank*, check_interval, cmci_disabled and ignore_ce. However, use of on_each_cpu() results in calling the function passed as the argument in interrupt context. This causes a flood of nested warnings from del_timer_sync() (it runs on each CPU) caused even by a simple file access like: $ echo 300 > /sys/devices/system/machinecheck/machinecheck0/check_interval Fortunately, these MCE-specific files are rarely used and AFAIK only few MCE geeks experience this warning. To remove the warning, move timer deletion outside of the interrupt context. Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
| * | | | | x86: Perf_event_amd.c needs <asm/apicdef.h>Randy Dunlap2011-09-271-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix (rare) build error by adding <asm/apicdef.h> header file: arch/x86/kernel/cpu/perf_event_amd.c:350:2: error: 'BAD_APICID' undeclared (first use in this function) Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Robert Richter <robert.richter@amd.com> Cc: Andre Przywara <andre.przywara@amd.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Link: http://lkml.kernel.org/r/4E820138.90301@xenotime.net Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | x86, perf: Clean up perf_event cpu codeKevin Winchester2011-09-269-460/+604
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The CPU support for perf events on x86 was implemented via included C files with #ifdefs. Clean this up by creating a new header file and compiling the vendor-specific files as needed. Signed-off-by: Kevin Winchester <kjwinchester@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1314747665-2090-1-git-send-email-kjwinchester@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | Merge commit 'v3.1-rc7' into perf/coreIngo Molnar2011-09-262-2/+3
| |\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge reason: Pick up the latest upstream fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | | perf, x86: Avoid kfree() in CPU_STARTINGPeter Zijlstra2011-08-143-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On -rt kfree() can schedule, but CPU_STARTING is before the CPU is fully up and running. These are contradictory, so avoid it. Instead push the kfree() to CPU_ONLINE where we're free to schedule. Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/n/tip-kwd4j6ayld5thrscvaxgjquv@git.kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | | locking, x86: mce: Annotate cmci_discover_lock as rawThomas Gleixner2011-09-131-5/+5
| |/ / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The cmci_discover_lock can be taken in atomic context (cpu bring up sequence) and therefore cannot be preempted on -rt. In mainline this change documents the low level nature of the lock - otherwise there's no functional difference. Lockdep and Sparse checking will work as usual. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | x86, perf: Check that current->mm is alive before getting user callchainAndrey Vagin2011-08-311-0/+3
| |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An event may occur when an mm is already released. I added an event in dequeue_entity() and caught a panic with the following backtrace: [ 434.421110] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050 [ 434.421258] IP: [<ffffffff810464ac>] __get_user_pages_fast+0x9c/0x120 ... [ 434.421258] Call Trace: [ 434.421258] [<ffffffff8101ae81>] copy_from_user_nmi+0x51/0xf0 [ 434.421258] [<ffffffff8109a0d5>] ? sched_clock_local+0x25/0x90 [ 434.421258] [<ffffffff8101b048>] perf_callchain_user+0x128/0x170 [ 434.421258] [<ffffffff811154cd>] ? __perf_event_header__init_id+0xed/0x100 [ 434.421258] [<ffffffff81116690>] perf_prepare_sample+0x200/0x280 [ 434.421258] [<ffffffff81118da8>] __perf_event_overflow+0x1b8/0x290 [ 434.421258] [<ffffffff81065240>] ? tg_shares_up+0x0/0x670 [ 434.421258] [<ffffffff8104fe1a>] ? walk_tg_tree+0x6a/0xb0 [ 434.421258] [<ffffffff81118f44>] perf_swevent_overflow+0xc4/0xf0 [ 434.421258] [<ffffffff81119150>] do_perf_sw_event+0x1e0/0x250 [ 434.421258] [<ffffffff81119204>] perf_tp_event+0x44/0x70 [ 434.421258] [<ffffffff8105701f>] ftrace_profile_sched_block+0xdf/0x110 [ 434.421258] [<ffffffff8106121d>] dequeue_entity+0x2ad/0x2d0 [ 434.421258] [<ffffffff810614ec>] dequeue_task_fair+0x1c/0x60 [ 434.421258] [<ffffffff8105818a>] dequeue_task+0x9a/0xb0 [ 434.421258] [<ffffffff810581e2>] deactivate_task+0x42/0xe0 [ 434.421258] [<ffffffff814bc019>] thread_return+0x191/0x808 [ 434.421258] [<ffffffff81098a44>] ? switch_task_namespaces+0x24/0x60 [ 434.421258] [<ffffffff8106f4c4>] do_exit+0x464/0x910 [ 434.421258] [<ffffffff8106f9c8>] do_group_exit+0x58/0xd0 [ 434.421258] [<ffffffff8106fa57>] sys_exit_group+0x17/0x20 [ 434.421258] [<ffffffff8100b202>] system_call_fastpath+0x16/0x1b Signed-off-by: Andrey Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: stable@kernel.org Link: http://lkml.kernel.org/r/1314693156-24131-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | mtrr: fix UP breakage caused during switch to stop_machineTejun Heo2011-08-251-2/+0
|/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While removing custom rendezvous code and switching to stop_machine, commit 192d8857427d ("x86, mtrr: use stop_machine APIs for doing MTRR rendezvous") completely dropped mtrr setting code on !CONFIG_SMP breaking MTRR settting on UP. Fix it by removing the incorrect CONFIG_SMP. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Anders Eriksson <aeriksson@fastmail.fm> Tested-and-acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | perf, x86: Add model 45 SandyBridge supportYouquan Song2011-08-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support to Romely-EP SandyBridge. Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: Anhua Xu <anhua.xu@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1312264895-2010-1-git-send-email-youquan.song@intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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*---. \ \ Merge branches 'x86-detect-hyper-for-linus', 'x86-fpu-for-linus', ↵Linus Torvalds2011-07-232-2/+6
|\ \ \ \ \ | | | | |/ | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'x86-kexec-for-linus', 'x86-platform-for-linus', 'x86-quirks-for-linus', 'x86-tsc-for-linus' and 'x86-smpboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-detect-hyper-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, hyper: Change hypervisor detection order * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86-32, fpu: Fix DNA exception during check_fpu() * 'x86-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: kexec, x86: Fix incorrect jump back address if not preserving context * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, config: Introduce an INTEL_MID configuration * 'x86-quirks-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, quirks: Use pci_dev->revision * 'x86-tsc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86: tsc: Remove unneeded DMI-based blacklisting * 'x86-smpboot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, boot: Wait for boot cpu to show up if nr_cpus limit is about to hit
| | * / | x86-32, fpu: Fix DNA exception during check_fpu()Suresh Siddha2011-06-301-0/+4
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before check_fpu() is called, we have cr0.TS bit set and hence the floating point code to check the FDIV bug was generating a DNA exception. Use kernel_fpu_begin()/kernel_fpu_end() around the floating point code to avoid this unnecessary device not available exception during boot. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1309479572.2665.1372.camel@sbsiddha-MOBL3.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * / / x86, hyper: Change hypervisor detection orderAnupam Chanda2011-07-081-2/+2
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Detect Xen before HyperV because in Viridian compatibility mode Xen presents itself as HyperV. Move Xen to the top since it seems more likely that Xen would emulate VMware than vice versa. Signed-off-by: Anupam Chanda <achanda@nicira.com> Link: http://lkml.kernel.org/r/1310150570-26810-1-git-send-email-achanda@nicira.com Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Yaozu (Eddie) Dong <eddie.dong@intel.com> Reviewed-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | | Merge branch 'x86-mtrr-for-linus' of ↵Linus Torvalds2011-07-221-136/+46
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-mtrr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, mtrr: Use pci_dev->revision x86, mtrr: use stop_machine APIs for doing MTRR rendezvous stop_machine: implement stop_machine_from_inactive_cpu() stop_machine: reorganize stop_cpus() implementation x86, mtrr: lock stop machine during MTRR rendezvous sequence
| * | | x86, mtrr: Use pci_dev->revisionSergei Shtylyov2011-07-021-8/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This code uses PCI_CLASS_REVISION instead of PCI_REVISION_ID, so it wasn't converted by commit 44c10138fd4 ("PCI: Change all drivers to use pci_device->revision") before being moved to arch/x86/... Do it now at last -- and save one level of indentation... Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/201107012242.08347.sshtylyov@ru.mvista.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | x86, mtrr: use stop_machine APIs for doing MTRR rendezvousSuresh Siddha2011-06-271-151/+41
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MTRR rendezvous sequence is not implemened using stop_machine() before, as this gets called both from the process context aswell as the cpu online paths (where the cpu has not come online and the interrupts are disabled etc). Now that we have a new stop_machine_from_inactive_cpu() API, use it for rendezvous during mtrr init of a logical processor that is coming online. For the rest (runtime MTRR modification, system boot, resume paths), use stop_machine() to implement the rendezvous sequence. This will consolidate and cleanup the code. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/20110623182057.076997177@sbsiddha-MOBL3.sc.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| * | | x86, mtrr: lock stop machine during MTRR rendezvous sequenceSuresh Siddha2011-06-271-0/+23
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | MTRR rendezvous sequence using stop_one_cpu_nowait() can potentially happen in parallel with another system wide rendezvous using stop_machine(). This can lead to deadlock (The order in which works are queued can be different on different cpu's. Some cpu's will be running the first rendezvous handler and others will be running the second rendezvous handler. Each set waiting for the other set to join for the system wide rendezvous, leading to a deadlock). MTRR rendezvous sequence is not implemented using stop_machine() as this gets called both from the process context aswell as the cpu online paths (where the cpu has not come online and the interrupts are disabled etc). stop_machine() works with only online cpus. For now, take the stop_machine mutex in the MTRR rendezvous sequence that gets called from an online cpu (here we are in the process context and can potentially sleep while taking the mutex). And the MTRR rendezvous that gets triggered during cpu online doesn't need to take this stop_machine lock (as the stop_machine() already ensures that there is no cpu hotplug going on in parallel by doing get_online_cpus()) TBD: Pursue a cleaner solution of extending the stop_machine() infrastructure to handle the case where the calling cpu is still not online and use this for MTRR rendezvous sequence. fixes: https://bugzilla.novell.com/show_bug.cgi?id=672008 Reported-by: Vadim Kotelnikov <vadimuzzz@inbox.ru> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/20110623182056.807230326@sbsiddha-MOBL3.sc.intel.com Cc: stable@kernel.org # 2.6.35+, backport a week or two after this gets more testing in mainline Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>