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2014-08-13Merge branch 'x86-xsave-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/xsave changes from Peter Anvin: "This is a patchset to support the XSAVES instruction required to support context switch of supervisor-only features in upcoming silicon. This patchset missed the 3.16 merge window, which is why it is based on 3.15-rc7" * 'x86-xsave-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, xsave: Add forgotten inline annotation x86/xsaves: Clean up code in xstate offsets computation in xsave area x86/xsave: Make it clear that the XSAVE macros use (%edi)/(%rdi) Define kernel API to get address of each state in xsave area x86/xsaves: Enable xsaves/xrstors x86/xsaves: Call booting time xsaves and xrstors in setup_init_fpu_buf x86/xsaves: Save xstate to task's xsave area in __save_fpu during booting time x86/xsaves: Add xsaves and xrstors support for booting time x86/xsaves: Clear reserved bits in xsave header x86/xsaves: Use xsave/xrstor for saving and restoring user space context x86/xsaves: Use xsaves/xrstors for context switch x86/xsaves: Use xsaves/xrstors to save and restore xsave area x86/xsaves: Define a macro for handling xsave/xrstor instruction fault x86/xsaves: Define macros for xsave instructions x86/xsaves: Change compacted format xsave area header x86/alternative: Add alternative_input_2 to support alternative with two features and input x86/xsaves: Add a kernel parameter noxsaves to disable xsaves/xrstors
2014-08-04Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm changes from Ingo Molnar: "The main change in this cycle is the rework of the TLB range flushing code, to simplify, fix and consolidate the code. By Dave Hansen" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Set TLB flush tunable to sane value (33) x86/mm: New tunable for single vs full TLB flush x86/mm: Add tracepoints for TLB flushes x86/mm: Unify remote INVLPG code x86/mm: Fix missed global TLB flush stat x86/mm: Rip out complicated, out-of-date, buggy TLB flushing x86/mm: Clean up the TLB flushing code x86/smep: Be more informative when signalling an SMEP fault
2014-07-31x86/mm: Rip out complicated, out-of-date, buggy TLB flushingDave Hansen
I think the flush_tlb_mm_range() code that tries to tune the flush sizes based on the CPU needs to get ripped out for several reasons: 1. It is obviously buggy. It uses mm->total_vm to judge the task's footprint in the TLB. It should certainly be using some measure of RSS, *NOT* ->total_vm since only resident memory can populate the TLB. 2. Haswell, and several other CPUs are missing from the intel_tlb_flushall_shift_set() function. Thus, it has been demonstrated to bitrot quickly in practice. 3. It is plain wrong in my vm: [ 0.037444] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0 [ 0.037444] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0 [ 0.037444] tlb_flushall_shift: 6 Which leads to it to never use invlpg. 4. The assumptions about TLB refill costs are wrong: http://lkml.kernel.org/r/1337782555-8088-3-git-send-email-alex.shi@intel.com (more on this in later patches) 5. I can not reproduce the original data: https://lkml.org/lkml/2012/5/17/59 I believe the sample times were too short. Running the benchmark in a loop yields times that vary quite a bit. Note that this leaves us with a static ceiling of 1 page. This is a conservative, dumb setting, and will be revised in a later patch. This also removes the code which attempts to predict whether we are flushing data or instructions. We expect instruction flushes to be relatively rare and not worth tuning for explicitly. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Link: http://lkml.kernel.org/r/20140731154055.ABC88E89@viggo.jf.intel.com Acked-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-18Merge tag 'v3.16-rc1' into x86/cpufeatureH. Peter Anvin
Linux 3.16-rc1 Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-06-12Merge branch 'perf-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Ingo Molnar: "A second round of perf updates: - wide reaching kprobes sanitization and robustization, with the hope of fixing all 'probe this function crashes the kernel' bugs, by Masami Hiramatsu. - uprobes updates from Oleg Nesterov: tmpfs support, corner case fixes and robustization work. - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo et al: * Add support to accumulate hist periods (Namhyung Kim) * various fixes, refactorings and enhancements" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits) perf: Differentiate exec() and non-exec() comm events perf: Fix perf_event_comm() vs. exec() assumption uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates perf/documentation: Add description for conditional branch filter perf/x86: Add conditional branch filtering support perf/tool: Add conditional branch filter 'cond' to perf record perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND' uprobes: Teach copy_insn() to support tmpfs uprobes: Shift ->readpage check from __copy_insn() to uprobe_register() perf/x86: Use common PMU interrupt disabled code perf/ARM: Use common PMU interrupt disabled code perf: Disable sampled events if no PMU interrupt perf: Fix use after free in perf_remove_from_context() perf tools: Fix 'make help' message error perf record: Fix poll return value propagation perf tools: Move elide bool into perf_hpp_fmt struct perf tools: Remove elide setup for SORT_MODE__MEMORY mode perf tools: Fix "==" into "=" in ui_browser__warning assignment perf tools: Allow overriding sysfs and proc finding with env var perf tools: Consider header files outside perf directory in tags target ...
2014-05-29x86/xsaves: Add a kernel parameter noxsaves to disable xsaves/xrstorsFenghua Yu
This patch adds a kernel parameter noxsaves to disable xsaves/xrstors feature. The kernel will fall back to use xsaveopt and xrstor to save and restor xstates. By using this parameter, xsave area occupies more memory because standard form of xsave area in xsaveopt/xrstor occupies more memory than compacted form of xsave area. This patch adds a description of the kernel parameter noxsaveopt in doc. The code to support the parameter noxsaveopt has been in the kernel before. This patch just adds the description of this parameter in the doc. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1401387164-43416-4-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-29x86/xsaves: Detect xsaves/xrstors featureFenghua Yu
Detect the xsaveopt, xsavec, xgetbv, and xsaves features in processor extended state enumberation sub-leaf (eax=0x0d, ecx=1): Bit 00: XSAVEOPT is available Bit 01: Supports XSAVEC and the compacted form of XRSTOR if set Bit 02: Supports XGETBV with ECX = 1 if set Bit 03: Supports XSAVES/XRSTORS and IA32_XSS if set The above features are defined in the new word 10 in cpu features. The IA32_XSS MSR (index DA0H) contains a state-component bitmap that specifies the state components that software has enabled xsaves and xrstors to manage. If the bit corresponding to a state component is clear in XCR0 | IA32_XSS, xsaves and xrstors will not operate on that state component, regardless of the value of the instruction mask. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1401387164-43416-3-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-05x86, vdso: Move the vvar and hpet mappings next to the 64-bit vDSOAndy Lutomirski
This makes the 64-bit and x32 vdsos use the same mechanism as the 32-bit vdso. Most of the churn is deleting all the old fixmap code. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/8af87023f57f6bb96ec8d17fce3f88018195b49b.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-05-05x86, vdso: Move syscall and sysenter setup into kernel/cpu/common.cAndy Lutomirski
This code is used during CPU setup, and it isn't strictly speaking related to the 32-bit vdso. It's easier to understand how this works when the code is closer to its callers. This also lets syscall32_cpu_init be static, which might save some trivial amount of kernel text. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Link: http://lkml.kernel.org/r/4e466987204e232d7b55a53ff6b9739f12237461.1399317206.git.luto@amacapital.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-04-24kprobes, x86: Prohibit probing on debug_stack_*()Masami Hiramatsu
Prohibit probing on debug_stack_reset and debug_stack_set_zero. Since the both functions are called from TRACE_IRQS_ON/OFF_DEBUG macros which run in int3 ist entry, probing it may cause a soft lockup. This happens when the kernel built with CONFIG_DYNAMIC_FTRACE=y and CONFIG_TRACE_IRQFLAGS=y. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Reviewed-by: Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Jan Beulich <JBeulich@suse.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/20140417081712.26341.32994.stgit@ltc230.yrl.intra.hitachi.co.jp Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-01Merge branch 'x86-threadinfo-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 threadinfo changes from Ingo Molnar: "The main change here is the consolidation/unification of 32 and 64 bit thread_info handling methods, from Steve Rostedt" * 'x86-threadinfo-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, threadinfo: Redo "x86: Use inline assembler to get sp" x86: Clean up dumpstack_64.c code x86: Keep thread_info on thread stack in x86_32 x86: Prepare removal of previous_esp from i386 thread_info structure x86: Nuke GET_THREAD_INFO_WITH_ESP() macro for i386 x86: Nuke the supervisor_stack field in i386 thread_info
2014-03-06x86: Keep thread_info on thread stack in x86_32Steven Rostedt
x86_64 uses a per_cpu variable kernel_stack to always point to the thread stack of current. This is where the thread_info is stored and is accessed from this location even when the irq or exception stack is in use. This removes the complexity of having to maintain the thread info on the stack when interrupts are running and having to copy the preempt_count and other fields to the interrupt stack. x86_32 uses the old method of copying the thread_info from the thread stack to the exception stack just before executing the exception. Having the two different requires #ifdefs and also the x86_32 way is a bit of a pain to maintain. By converting x86_32 to the same method of x86_64, we can remove #ifdefs, clean up the x86_32 code a little, and remove the overhead of the copy. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20110806012354.263834829@goodmis.org Link: http://lkml.kernel.org/r/20140206144321.852942014@goodmis.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-27x86, cpufeature: If we disable CLFLUSH, we should disable CLFLUSHOPTH. Peter Anvin
If we explicitly disable the use of CLFLUSH, we should disable the use of CLFLUSHOPT as well. Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/n/tip-jtdv7btppr4jgzxm3sxx1e74@git.kernel.org
2014-02-27x86, cpufeature: Rename X86_FEATURE_CLFLSH to X86_FEATURE_CLFLUSHH. Peter Anvin
We call this "clflush" in /proc/cpuinfo, and have cpu_has_clflush()... let's be consistent and just call it that. Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/n/tip-mlytfzjkvuf739okyn40p8a5@git.kernel.org
2014-02-13x86, smap: Don't enable SMAP if CONFIG_X86_SMAP is disabledH. Peter Anvin
If SMAP support is not compiled into the kernel, don't enable SMAP in CR4 -- in fact, we should clear it, because the kernel doesn't contain the proper STAC/CLAC instructions for SMAP support. Found by Fengguang Wu's test system. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Link: http://lkml.kernel.org/r/20140213124550.GA30497@localhost Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.7+
2014-01-03x86, cpu: Detect more TLB configurationKirill A. Shutemov
The Intel Software Developer’s Manual covers few more TLB configurations exposed as CPUID 2 descriptors: 61H Instruction TLB: 4 KByte pages, fully associative, 48 entries 63H Data TLB: 1 GByte pages, 4-way set associative, 4 entries 76H Instruction TLB: 2M/4M pages, fully associative, 8 entries B5H Instruction TLB: 4KByte pages, 8-way set associative, 64 entries B6H Instruction TLB: 4KByte pages, 8-way set associative, 128 entries C1H Shared 2nd-Level TLB: 4 KByte/2MByte pages, 8-way associative, 1024 entries C2H DTLB DTLB: 2 MByte/$MByte pages, 4-way associative, 16 entries Let's detect them as well. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Link: http://lkml.kernel.org/r/1387801018-14499-1-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-11-12Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu changes from Ingo Molnar: "The biggest change that stands out is the increase of the CONFIG_NR_CPUS range from 4096 to 8192 - as real hardware out there already went beyond 4k CPUs ... We only allow more than 512 CPUs if offstack cpumasks are enabled. CONFIG_MAXSMP=y remains to be the 'you are nuts!' extreme testcase, which now means a max of 8192 CPUs" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/cpu: Increase max CPU count to 8192 x86/cpu: Allow higher NR_CPUS values x86/cpu: Always print SMP information in /proc/cpuinfo x86/cpu: Track legacy CPU model data only on 32-bit kernels
2013-10-26x86/cpu: Track legacy CPU model data only on 32-bit kernelsJan Beulich
struct cpu_dev's c_models is only ever set inside CONFIG_X86_32 conditionals (or code that's being built for 32-bit only), so there's no use of reserving the (empty) space for the model names in a 64-bit kernel. Similarly, c_size_cache is only used in the #else of a CONFIG_X86_64 conditional, so reserving space for (and in one case even initializing) that field is pointless for 64-bit kernels too. While moving both fields to the end of the structure, I also noticed that: - the c_models array size was one too small, potentially causing table_lookup_model() to return garbage on Intel CPUs (intel.c's instance was lacking the sentinel with family being zero), so the patch bumps that by one, - c_models' vendor sub-field was unused (and anyway redundant with the base structure's c_x86_vendor field), so the patch deletes it. Also rename the legacy fields so that their legacy nature stands out and comment their declarations. Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-25sched, x86: Provide a per-cpu preempt_count implementationPeter Zijlstra
Convert x86 to use a per-cpu preemption count. The reason for doing so is that accessing per-cpu variables is a lot cheaper than accessing thread_info variables. We still need to save/restore the actual preemption count due to PREEMPT_ACTIVE so we place the per-cpu __preempt_count variable in the same cache-line as the other hot __switch_to() variables such as current_task. NOTE: this save/restore is required even for !PREEMPT kernels as cond_resched() also relies on preempt_count's PREEMPT_ACTIVE to ignore task_struct::state. Also rename thread_info::preempt_count to ensure nobody is 'accidentally' still poking at it. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-gzn5rfsf8trgjoqx8hyayy3q@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-06x86, asmlinkage: Make several variables used from assembler/linker script ↵Andi Kleen
visible Plus one function, load_gs_index(). Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-10-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-07-14x86: delete __cpuinit usage from all x86 filesPaul Gortmaker
The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/x86 uses of the __cpuinit macros from all C files. x86 only had the one __CPUINIT used in assembly files, and it wasn't paired off with a .previous or a __FINIT, so we can delete it directly w/o any corresponding additional change there. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2013-07-02Merge branch 'x86-tracing-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 tracing updates from Ingo Molnar: "This tree adds IRQ vector tracepoints that are named after the handler and which output the vector #, based on a zero-overhead approach that relies on changing the IDT entries, by Seiji Aguchi. The new tracepoints look like this: # perf list | grep -i irq_vector irq_vectors:local_timer_entry [Tracepoint event] irq_vectors:local_timer_exit [Tracepoint event] irq_vectors:reschedule_entry [Tracepoint event] irq_vectors:reschedule_exit [Tracepoint event] irq_vectors:spurious_apic_entry [Tracepoint event] irq_vectors:spurious_apic_exit [Tracepoint event] irq_vectors:error_apic_entry [Tracepoint event] irq_vectors:error_apic_exit [Tracepoint event] [...]" * 'x86-tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tracing: Add config option checking to the definitions of mce handlers trace,x86: Do not call local_irq_save() in load_current_idt() trace,x86: Move creation of irq tracepoints from apic.c to irq.c x86, trace: Add irq vector tracepoints x86: Rename variables for debugging x86, trace: Introduce entering/exiting_irq() tracing: Add DEFINE_EVENT_FN() macro
2013-06-20x86, trace: Add irq vector tracepointsSeiji Aguchi
[Purpose of this patch] As Vaibhav explained in the thread below, tracepoints for irq vectors are useful. http://www.spinics.net/lists/mm-commits/msg85707.html <snip> The current interrupt traces from irq_handler_entry and irq_handler_exit provide when an interrupt is handled. They provide good data about when the system has switched to kernel space and how it affects the currently running processes. There are some IRQ vectors which trigger the system into kernel space, which are not handled in generic IRQ handlers. Tracing such events gives us the information about IRQ interaction with other system events. The trace also tells where the system is spending its time. We want to know which cores are handling interrupts and how they are affecting other processes in the system. Also, the trace provides information about when the cores are idle and which interrupts are changing that state. <snip> On the other hand, my usecase is tracing just local timer event and getting a value of instruction pointer. I suggested to add an argument local timer event to get instruction pointer before. But there is another way to get it with external module like systemtap. So, I don't need to add any argument to irq vector tracepoints now. [Patch Description] Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events. But there is an above use case to trace specific irq_vector rather than tracing all events. In this case, we are concerned about overhead due to unwanted events. So, add following tracepoints instead of introducing irq_vector_entry/exit. so that we can enable them independently. - local_timer_vector - reschedule_vector - call_function_vector - call_function_single_vector - irq_work_entry_vector - error_apic_vector - thermal_apic_vector - threshold_apic_vector - spurious_apic_vector - x86_platform_ipi_vector Also, introduce a logic switching IDT at enabling/disabling time so that a time penalty makes a zero when tracepoints are disabled. Detailed explanations are as follows. - Create trace irq handlers with entering_irq()/exiting_irq(). - Create a new IDT, trace_idt_table, at boot time by adding a logic to _set_gate(). It is just a copy of original idt table. - Register the new handlers for tracpoints to the new IDT by introducing macros to alloc_intr_gate() called at registering time of irq_vector handlers. - Add checking, whether irq vector tracing is on/off, into load_current_idt(). This has to be done below debug checking for these reasons. - Switching to debug IDT may be kicked while tracing is enabled. - On the other hands, switching to trace IDT is kicked only when debugging is disabled. In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being used for other purposes. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/51C323ED.5050708@hds.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-20x86: Rename variables for debuggingSeiji Aguchi
Rename variables for debugging to describe meaning of them precisely. Also, introduce a generic way to switch IDT by checking a current state, debug on/off. Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com> Link: http://lkml.kernel.org/r/51C323A8.7050905@hds.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org>
2013-06-20x86: Add a static_cpu_has_safe variantBorislav Petkov
We want to use this in early code where alternatives might not have run yet and for that case we fall back to the dynamic boot_cpu_has. For that, force a 5-byte jump since the compiler could be generating differently sized jumps for each label. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1370772454-6106-5-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-06-20x86: Sanity-check static_cpu_has usageBorislav Petkov
static_cpu_has may be used only after alternatives have run. Before that it always returns false if constant folding with __builtin_constant_p() doesn't happen. And you don't want that. This patch is the result of me debugging an issue where I overzealously put static_cpu_has in code which executed before alternatives have run and had to spend some time with scratching head and cursing at the monitor. So add a jump to a warning which screams loudly when we use this function too early. The alternatives patch that check away in conjunction with patching the rest of the kernel image. [ hpa: factored this into its own configuration option. If we want to have an overarching option, it should be an option which selects other options, not as a group option in the source code. ] Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1370772454-6106-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-06-20x86, cpu: Add a synthetic, always true, cpu featureBorislav Petkov
This will be used in alternatives later as an always-replace flag. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1370772454-6106-2-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-06-06x86: Get rid of ->hard_math and all the FPU asm fuH. Peter Anvin
Reimplement FPU detection code in C and drop old, not-so-recommended detection method in asm. Move all the relevant stuff into i387.c where it conceptually belongs. Finally drop cpuinfo_x86.hard_math. [ hpa: huge thanks to Borislav for taking my original concept patch and productizing it ] [ Boris, note to self: do not use static_cpu_has before alternatives! ] Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1367244262-29511-2-git-send-email-bp@alien8.de Link: http://lkml.kernel.org/r/1365436666-9837-2-git-send-email-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-02x86, cpu: Expand cpufeature facility to include cpu bugsBorislav Petkov
We add another 32-bit vector at the end of the ->x86_capability bitvector which collects bugs present in CPUs. After all, a CPU bug is a kind of a capability, albeit a strange one. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1363788448-31325-2-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-01-31x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on APFenghua Yu
In 64 bit, load ucode on AP in cpu_init(). In 32 bit, show ucode loading info on AP in cpu_init(). Microcode has been loaded earlier before paging. Now it is safe to show the loading microcode info on this AP. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1356075872-3054-5-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-31x86/common.c: Make have_cpuid_p() a global functionFenghua Yu
Remove static declaration in have_cpuid_p() to make it a global function. The function will be called in early loading microcode. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1356075872-3054-4-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-12-12Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull big execve/kernel_thread/fork unification series from Al Viro: "All architectures are converted to new model. Quite a bit of that stuff is actually shared with architecture trees; in such cases it's literally shared branch pulled by both, not a cherry-pick. A lot of ugliness and black magic is gone (-3KLoC total in this one): - kernel_thread()/kernel_execve()/sys_execve() redesign. We don't do syscalls from kernel anymore for either kernel_thread() or kernel_execve(): kernel_thread() is essentially clone(2) with callback run before we return to userland, the callbacks either never return or do successful do_execve() before returning. kernel_execve() is a wrapper for do_execve() - it doesn't need to do transition to user mode anymore. As a result kernel_thread() and kernel_execve() are arch-independent now - they live in kernel/fork.c and fs/exec.c resp. sys_execve() is also in fs/exec.c and it's completely architecture-independent. - daemonize() is gone, along with its parts in fs/*.c - struct pt_regs * is no longer passed to do_fork/copy_process/ copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump. - sys_fork()/sys_vfork()/sys_clone() unified; some architectures still need wrappers (ones with callee-saved registers not saved in pt_regs on syscall entry), but the main part of those suckers is in kernel/fork.c now." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits) do_coredump(): get rid of pt_regs argument print_fatal_signal(): get rid of pt_regs argument ptrace_signal(): get rid of unused arguments get rid of ptrace_signal_deliver() arguments new helper: signal_pt_regs() unify default ptrace_signal_deliver flagday: kill pt_regs argument of do_fork() death to idle_regs() don't pass regs to copy_process() flagday: don't pass regs to copy_thread() bfin: switch to generic vfork, get rid of pointless wrappers xtensa: switch to generic clone() openrisc: switch to use of generic fork and clone unicore32: switch to generic clone(2) score: switch to generic fork/vfork/clone c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone() take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h mn10300: switch to generic fork/vfork/clone h8300: switch to generic fork/vfork/clone tile: switch to generic clone() ... Conflicts: arch/microblaze/include/asm/Kbuild
2012-11-28death to idle_regs()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-14x86, hotplug: During CPU0 online, enable x2apic, set_numa_node.Fenghua Yu
Previously these functions were not run on the BSP (CPU 0, the boot processor) since the boot processor init would only be executed before this functionality was initialized. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1352835171-3958-11-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-10-01Merge branch 'x86-smap-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/smap support from Ingo Molnar: "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU feature on Intel CPUs: a hardware feature that prevents unintended user-space data access from kernel privileged code. It's turned on automatically when possible. This, in combination with SMEP, makes it even harder to exploit kernel bugs such as NULL pointer dereferences." Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added includes right next to each other. * 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, smep, smap: Make the switching functions one-way x86, suspend: On wakeup always initialize cr4 and EFER x86-32: Start out eflags and cr4 clean x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry x86, smap: Reduce the SMAP overhead for signal handling x86, smap: A page fault due to SMAP is an oops x86, smap: Turn on Supervisor Mode Access Prevention x86, smap: Add STAC and CLAC instructions to control user space access x86, uaccess: Merge prototypes for clear_user/__clear_user x86, smap: Add a header file with macros for STAC/CLAC x86, alternative: Add header guards to <asm/alternative-asm.h> x86, alternative: Use .pushsection/.popsection x86, smap: Add CR4 bit for SMAP x86-32, mm: The WP test should be done on a kernel page
2012-10-01Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/mm changes from Ingo Molnar: "The biggest change is new TLB partial flushing code for AMD CPUs. (The v3.6 kernel had the Intel CPU side code, see commits e0ba94f14f74..effee4b9b3b.) There's also various other refinements around the TLB flush code" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Distinguish TLB shootdown interrupts from other functions call interrupts x86/mm: Fix range check in tlbflush debugfs interface x86, cpu: Preset default tlb_flushall_shift on AMD x86, cpu: Add AMD TLB size detection x86, cpu: Push TLB detection CPUID check down x86, cpu: Fixup tlb_flushall_shift formatting
2012-10-01Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/fpu update from Ingo Molnar: "The biggest change is the addition of the non-lazy (eager) FPU saving support model and enabling it on CPUs with optimized xsaveopt/xrstor FPU state saving instructions. There are also various Sparse fixes" Fix up trivial add-add conflict in arch/x86/kernel/traps.c * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, kvm: fix kvm's usage of kernel_fpu_begin/end() x86, fpu: remove cpu_has_xmm check in the fx_finit() x86, fpu: make eagerfpu= boot param tri-state x86, fpu: enable eagerfpu by default for xsaveopt x86, fpu: decouple non-lazy/eager fpu restore from xsave x86, fpu: use non-lazy fpu restore for processors supporting xsave lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu() x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig() x86, fpu: drop_fpu() before restoring new state from sigframe x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels x86, fpu: Consolidate inline asm routines for saving/restoring fpu state x86, signal: Cleanup ifdefs and is_ia32, is_x32
2012-10-01Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 debug update from Ingo Molnar: "Various small enhancements" * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/debug: Dump family, model, stepping of the boot CPU x86/iommu: Use NULL instead of plain 0 for __IOMMU_INIT x86/iommu: Drop duplicate const in __IOMMU_INIT x86/fpu/xsave: Keep __user annotation in casts x86/pci/probe_roms: Add missing __iomem annotation to pci_map_biosrom() x86/signals: ia32_signal.c: add __user casts to fix sparse warnings x86/vdso: Add __user annotation to VDSO32_SYMBOL x86: Fix __user annotations in asm/sys_ia32.h
2012-09-27x86, smep, smap: Make the switching functions one-wayH. Peter Anvin
There is no fundamental reason why we should switch SMEP and SMAP on during early cpu initialization just to switch them off again. Now with %eflags and %cr4 forced to be initialized to a clean state, we only need the one-way enable. Also, make the functions inline to make them (somewhat) harder to abuse. This does mean that SMEP and SMAP do not get initialized anywhere near as early. Even using early_param() instead of __setup() doesn't give us control early enough to do this during the early cpu initialization phase. This seems reasonable to me, because SMEP and SMAP should not matter until we have userspace to protect ourselves from, but it does potentially make it possible for a bug involving a "leak of permissions to userspace" to get uncaught. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-21Merge branch 'x86/fpu' into x86/smapH. Peter Anvin
Reason for merge: x86/fpu changed the structure of some of the code that x86/smap changes; mostly fpu-internal.h but also minor changes to the signal code. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Resolved Conflicts: arch/x86/ia32/ia32_signal.c arch/x86/include/asm/fpu-internal.h arch/x86/kernel/signal.c
2012-09-21x86, smap: Turn on Supervisor Mode Access PreventionH. Peter Anvin
If Supervisor Mode Access Prevention is available and not disabled by the user, turn it on. Also fix the expansion of SMEP (Supervisor Mode Execution Prevention.) Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-10-git-send-email-hpa@linux.intel.com
2012-09-21x86, smap: Add STAC and CLAC instructions to control user space accessH. Peter Anvin
When Supervisor Mode Access Prevention (SMAP) is enabled, access to userspace from the kernel is controlled by the AC flag. To make the performance of manipulating that flag acceptable, there are two new instructions, STAC and CLAC, to set and clear it. This patch adds those instructions, via alternative(), when the SMAP feature is enabled. It also adds X86_EFLAGS_AC unconditionally to the SYSCALL entry mask; there is simply no reason to make that one conditional. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
2012-09-19x86/debug: Dump family, model, stepping of the boot CPUBorislav Petkov
When acting on a user bug report, we find ourselves constantly asking for /proc/cpuinfo in order to know the exact family, model, stepping of the CPU in question. Instead of having to ask this, add this to dmesg so that it is visible and no ambiguities can ensue from looking at the official name string of the CPU coming from CPUID and trying to map it to f/m/s. Output then looks like this: [ 0.146041] smpboot: CPU0: AMD FX(tm)-8100 Eight-Core Processor (fam: 15, model: 01, stepping: 02) Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Link: http://lkml.kernel.org/r/1347640666-13638-1-git-send-email-bp@amd64.org [ tweaked it minimally to add commas. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-09-18x86, fpu: decouple non-lazy/eager fpu restore from xsaveSuresh Siddha
Decouple non-lazy/eager fpu restore policy from the existence of the xsave feature. Introduce a synthetic CPUID flag to represent the eagerfpu policy. "eagerfpu=on" boot paramter will enable the policy. Requested-by: H. Peter Anvin <hpa@zytor.com> Requested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1347300665-6209-2-git-send-email-suresh.b.siddha@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2012-09-13x86: Drop unnecessary kernel_eflags variable on 64-bitIan Campbell
On 64 bit x86 we save the current eflags in cpu_init for use in ret_from_fork. Strictly speaking reserved bits in EFLAGS should be read as written but in practise it is unlikely that EFLAGS could ever be extended in this way and the kernel alread clears any undefined flags early on. The equivalent 32 bit code simply hard codes 0x0202 as the new EFLAGS. This change makes 64 bit use the same mechanism to setup the initial EFLAGS on fork. Note that 64 bit resets EFLAGS before calling schedule_tail() as opposed to 32 bit which calls schedule_tail() first. Therefore the correct value for EFLAGS has opposite IF bit. Signed-off-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Andi Kleen <ak@linux.intel.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Pekka Enberg <penberg@kernel.org> Cc: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/20120824195847.GA31628@moon Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-08x86, avx: don't use avx instructions with "noxsave" boot paramSuresh Siddha
Clear AVX, AVX2 features along with clearing XSAVE feature bits, as part of the parsing "noxsave" parameter. Fixes the kernel boot panic with "noxsave" boot parameter. We could have checked cpu_has_osxsave along with cpu_has_avx etc, but Peter mentioned clearing the feature bits will be better for uses like static_cpu_has() etc. Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1343755754.2041.2.camel@sbsiddha-desk.sc.intel.com Cc: <stable@vger.kernel.org> # v3.5 Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-08-06x86, cpu: Push TLB detection CPUID check downBorislav Petkov
Push the max CPUID leaf check into the ->detect_tlb function and remove general test case from the generic path. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1344272439-29080-3-git-send-email-bp@amd64.org Acked-by: Alex Shi <alex.shi@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-08-06x86, cpu: Fixup tlb_flushall_shift formattingBorislav Petkov
The TLB characteristics appeared like this in dmesg: [ 0.065817] Last level iTLB entries: 4KB 512, 2MB 1024, 4MB 512 [ 0.065817] Last level dTLB entries: 4KB 1024, 2MB 1024, 4MB 512 [ 0.065817] tlb_flushall_shift is 0xffffffff where tlb_flushall_shift is actually -1 but dumped as a hex number. However, the Kconfig option CONFIG_DEBUG_TLBFLUSH and the rest of the code treats this as a signed decimal and states "If you set it to -1, the code flushes the whole TLB unconditionally." So, fix its formatting in accordance with the other references to it. Signed-off-by: Borislav Petkov <borislav.petkov@amd.com> Link: http://lkml.kernel.org/r/1344272439-29080-2-git-send-email-bp@amd64.org Acked-by: Alex Shi <alex.shi@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2012-07-26Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86/mm changes from Peter Anvin: "The big change here is the patchset by Alex Shi to use INVLPG to flush only the affected pages when we only need to flush a small page range. It also removes the special INVALIDATE_TLB_VECTOR interrupts (32 vectors!) and replace it with an ordinary IPI function call." Fix up trivial conflicts in arch/x86/include/asm/apic.h (added code next to changed line) * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tlb: Fix build warning and crash when building for !SMP x86/tlb: do flush_tlb_kernel_range by 'invlpg' x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR x86/tlb: enable tlb flush range support for x86 mm/mmu_gather: enable tlb flush range in generic mmu_gather x86/tlb: add tlb_flushall_shift knob into debugfs x86/tlb: add tlb_flushall_shift for specific CPU x86/tlb: fall back to flush all when meet a THP large page x86/flush_tlb: try flush_tlb_single one by one in flush_tlb_range x86/tlb_info: get last level TLB entry number of CPU x86: Add read_mostly declaration/definition to variables from smp.h x86: Define early read-mostly per-cpu macros
2012-06-27x86/tlb: add tlb_flushall_shift for specific CPUAlex Shi
Testing show different CPU type(micro architectures and NUMA mode) has different balance points between the TLB flush all and multiple invlpg. And there also has cases the tlb flush change has no any help. This patch give a interface to let x86 vendor developers have a chance to set different shift for different CPU type. like some machine in my hands, balance points is 16 entries on Romely-EP; while it is at 8 entries on Bloomfield NHM-EP; and is 256 on IVB mobile CPU. but on model 15 core2 Xeon using invlpg has nothing help. For untested machine, do a conservative optimization, same as NHM CPU. Signed-off-by: Alex Shi <alex.shi@intel.com> Link: http://lkml.kernel.org/r/1340845344-27557-5-git-send-email-alex.shi@intel.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>