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* x86: opt into HAVE_COPY_THREAD_TLS, for both 32-bit and 64-bitJosh Triplett2015-07-011-4/+4
| | | | | | | | | | | | | | | | | | | For 32-bit userspace on a 64-bit kernel, this requires modifying stub32_clone to actually swap the appropriate arguments to match CONFIG_CLONE_BACKWARDS, rather than just leaving the C argument for tls broken. Patch co-authored by Josh Triplett and Thiago Macieira. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thiago Macieira <thiago.macieira@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-core-for-linus' of ↵Linus Torvalds2015-06-231-3/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Ingo Molnar: "There were so many changes in the x86/asm, x86/apic and x86/mm topics in this cycle that the topical separation of -tip broke down somewhat - so the result is a more traditional architecture pull request, collected into the 'x86/core' topic. The topics were still maintained separately as far as possible, so bisectability and conceptual separation should still be pretty good - but there were a handful of merge points to avoid excessive dependencies (and conflicts) that would have been poorly tested in the end. The next cycle will hopefully be much more quiet (or at least will have fewer dependencies). The main changes in this cycle were: * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas Gleixner) - This is the second and most intrusive part of changes to the x86 interrupt handling - full conversion to hierarchical interrupt domains: [IOAPIC domain] ----- | [MSI domain] --------[Remapping domain] ----- [ Vector domain ] | (optional) | [HPET MSI domain] ----- | | [DMAR domain] ----------------------------- | [Legacy domain] ----------------------------- This now reflects the actual hardware and allowed us to distangle the domain specific code from the underlying parent domain, which can be optional in the case of interrupt remapping. It's a clear separation of functionality and removes quite some duct tape constructs which plugged the remap code between ioapic/msi/hpet and the vector management. - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt injection into guests (Feng Wu) * x86/asm changes: - Tons of cleanups and small speedups, micro-optimizations. This is in preparation to move a good chunk of the low level entry code from assembly to C code (Denys Vlasenko, Andy Lutomirski, Brian Gerst) - Moved all system entry related code to a new home under arch/x86/entry/ (Ingo Molnar) - Removal of the fragile and ugly CFI dwarf debuginfo annotations. Conversion to C will reintroduce many of them - but meanwhile they are only getting in the way, and the upstream kernel does not rely on them (Ingo Molnar) - NOP handling refinements. (Borislav Petkov) * x86/mm changes: - Big PAT and MTRR rework: making the code more robust and preparing to phase out exposing direct MTRR interfaces to drivers - in favor of using PAT driven interfaces (Toshi Kani, Luis R Rodriguez, Borislav Petkov) - New ioremap_wt()/set_memory_wt() interfaces to support Write-Through cached memory mappings. This is especially important for good performance on NVDIMM hardware (Toshi Kani) * x86/ras changes: - Add support for deferred errors on AMD (Aravind Gopalakrishnan) This is an important RAS feature which adds hardware support for poisoned data. That means roughly that the hardware marks data which it has detected as corrupted but wasn't able to correct, as poisoned data and raises an APIC interrupt to signal that in the form of a deferred error. It is the OS's responsibility then to take proper recovery action and thus prolonge system lifetime as far as possible. - Add support for Intel "Local MCE"s: upcoming CPUs will support CPU-local MCE interrupts, as opposed to the traditional system- wide broadcasted MCE interrupts (Ashok Raj) - Misc cleanups (Borislav Petkov) * x86/platform changes: - Intel Atom SoC updates ... and lots of other cleanups, fixlets and other changes - see the shortlog and the Git log for details" * 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits) x86/hpet: Use proper hpet device number for MSI allocation x86/hpet: Check for irq==0 when allocating hpet MSI interrupts x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail genirq: Prevent crash in irq_move_irq() genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain iommu, x86: Properly handle posted interrupts for IOMMU hotplug iommu, x86: Provide irq_remapping_cap() interface iommu, x86: Setup Posted-Interrupts capability for Intel iommu iommu, x86: Add cap_pi_support() to detect VT-d PI capability iommu, x86: Avoid migrating VT-d posted interrupts iommu, x86: Save the mode (posted or remapped) of an IRTE iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip iommu: dmar: Provide helper to copy shared irte fields iommu: dmar: Extend struct irte for VT-d Posted-Interrupts iommu: Add new member capability to struct irq_remap_ops x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry() ...
| * x86/entry: Remove unused 'kernel_stack' per-cpu variableDenys Vlasenko2015-05-081-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1429889495-27850-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/fpu: Rename fpu-internal.h to fpu/internal.hIngo Molnar2015-05-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This unifies all the FPU related header files under a unified, hiearchical naming scheme: - asm/fpu/types.h: FPU related data types, needed for 'struct task_struct', widely included in almost all kernel code, and hence kept as small as possible. - asm/fpu/api.h: FPU related 'public' methods exported to other subsystems. - asm/fpu/internal.h: FPU subsystem internal methods - asm/fpu/xsave.h: XSAVE support internal methods (Also standardize the header guard in asm/fpu/internal.h.) Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/fpu: Use 'struct fpu' in switch_fpu_finish()Ingo Molnar2015-05-191-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Migrate this function to pure 'struct fpu' usage. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/fpu: Use 'struct fpu' in switch_fpu_prepare()Ingo Molnar2015-05-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Migrate this function to pure 'struct fpu' usage. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/fpu: Rename math_state_restore() to fpu__restore()Ingo Molnar2015-05-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Move to the new fpu__*() namespace. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/fpu: Fix header file dependencies of fpu-internal.hIngo Molnar2015-05-191-1/+0
|/ | | | | | | | | | | | | | | | | | | | | | Fix a minor header file dependency bug in asm/fpu-internal.h: it relies on i387.h but does not include it. All users of fpu-internal.h included it explicitly. Also remove unnecessary includes, to reduce compilation time. This also makes it easier to use it as a standalone header file for FPU internals, such as an upcoming C module in arch/x86/kernel/fpu/. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86_64, asm: Work around AMD SYSRET SS descriptor attribute issueAndy Lutomirski2015-04-271-0/+28
| | | | | | | | | | | | | | | | | | | AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with SS == 0 results in an invalid usermode state in which SS is apparently equal to __USER_DS but causes #SS if used. Work around the issue by setting SS to __KERNEL_DS __switch_to, thus ensuring that SYSRET never happens with SS set to NULL. This was exposed by a recent vDSO cleanup. Fixes: e7d6eefaaa44 x86/vdso32/syscall.S: Do not load __USER32_DS to %ss Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Peter Anvin <hpa@zytor.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <vda.linux@googlemail.com> Cc: Brian Gerst <brgerst@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86/asm/entry: Get rid of KERNEL_STACK_OFFSETDenys Vlasenko2015-03-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PER_CPU_VAR(kernel_stack) was set up in a way where it points five stack slots below the top of stack. Presumably, it was done to avoid one "sub $5*8,%rsp" in syscall/sysenter code paths, where iret frame needs to be created by hand. Ironically, none of them benefits from this optimization, since all of them need to allocate additional data on stack (struct pt_regs), so they still have to perform subtraction. This patch eliminates KERNEL_STACK_OFFSET. PER_CPU_VAR(kernel_stack) now points directly to top of stack. pt_regs allocations are adjusted to allocate iret frame as well. Hopefully we can merge it later with 32-bit specific PER_CPU_VAR(cpu_current_top_of_stack) variable... Net result in generated code is that constants in several insns are changed. This change is necessary for changing struct pt_regs creation in SYSCALL64 code path from MOV to PUSH instructions. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1426785469-15125-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Fix execve() and sigreturn() syscalls to always return via IRETBrian Gerst2015-03-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both the execve() and sigreturn() family of syscalls have the ability to change registers in ways that may not be compatabile with the syscall path they were called from. In particular, SYSRET and SYSEXIT can't handle non-default %cs and %ss, and some bits in eflags. These syscalls have stubs that are hardcoded to jump to the IRET path, and not return to the original syscall path. The following commit: 76f5df43cab5e76 ("Always allocate a complete "struct pt_regs" on the kernel stack") recently changed this for some 32-bit compat syscalls, but introduced a bug where execve from a 32-bit program to a 64-bit program would fail because it still returned via SYSRETL. This caused Wine to fail when built for both 32-bit and 64-bit. This patch sets TIF_NOTIFY_RESUME for execve() and sigreturn() so that the IRET path is always taken on exit to userspace. Signed-off-by: Brian Gerst <brgerst@gmail.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1426978461-32089-1-git-send-email-brgerst@gmail.com [ Improved the changelog and comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Rename 'old_rsp' to 'rsp_scratch'Ingo Molnar2015-03-171-1/+1
| | | | | | | | | | | | | | | | | | Make clear that the usage of PER_CPU(old_rsp) is purely temporary, by renaming it to 'rsp_scratch'. Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Remove thread_struct::userspIngo Molnar2015-03-171-3/+0
| | | | | | | | | | | | | | | | | | | Nothing uses thread_struct::usersp anymore, so remove it. Originally-from: Denys Vlasenko <dvlasenk@redhat.com> Tested-by: Borislav Petkov <bp@alien8.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Simplify 'old_rsp' usageIngo Molnar2015-03-171-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove all manipulations of PER_CPU(old_rsp) in C code: - it is not used on SYSRET return anymore, and system entries are atomic, so updating it from the fork and context switch paths is pointless. - Tweak a few related comments as well: we no longer have a "partial stack frame" on entry, ever. Based on (split out of) patch from Denys Vlasenko. Originally-from: Denys Vlasenko <dvlasenk@redhat.com> Tested-by: Borislav Petkov <bp@alien8.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1426599779-8010-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry/64: Save user RSP in pt_regs->sp on SYSCALL64 fastpathDenys Vlasenko2015-03-101-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare for the removal of 'usersp', by simplifying PER_CPU(old_rsp) usage: - use it only as temp storage - store the userspace stack pointer immediately in pt_regs->sp on syscall entry, instead of using it later, on syscall exit. - change C code to use pt_regs->sp only, instead of PER_CPU(old_rsp) and task->thread.usersp. FIXUP/RESTORE_TOP_OF_STACK are simplified as well. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1425926364-9526-4-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Delay loading sp0 slightly on task switchAndy Lutomirski2015-03-071-3/+3
| | | | | | | | | | | | | | | | | | | | | | | The change: 75182b1632a8 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()") had the unintended side effect of changing the return value of current_thread_info() during part of the context switch process. Change it back. This has no effect as far as I can tell -- it's just for consistency. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/9fcaa47dd8487db59eed7a3911b6ae409476763e.1425692936.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/asm/entry: Rename 'init_tss' to 'cpu_tss'Andy Lutomirski2015-03-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | It has nothing to do with init -- there's only one TSS per cpu. Other names considered include: - current_tss: Confusing because we never switch the tss. - singleton_tss: Too long. This patch was generated with 's/init_tss/cpu_tss/g'. Followup patches will fix INIT_TSS and INIT_TSS_IST by hand. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/da29fb2a793e4f649d93ce2d1ed320ebe8516262.1425611534.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge tag 'v4.0-rc2' into x86/asm, to refresh the treeIngo Molnar2015-03-041-1/+1
|\ | | | | | | Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86: Store a per-cpu shadow copy of CR4Andy Lutomirski2015-02-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Context switches and TLB flushes can change individual bits of CR4. CR4 reads take several cycles, so store a shadow copy of CR4 in a per-cpu variable. To avoid wasting a cache line, I added the CR4 shadow to cpu_tlbstate, which is already touched in switch_mm. The heaviest users of the cr4 shadow will be switch_mm and __switch_to_xtra, and __switch_to_xtra is called shortly after switch_mm during context switch, so the cacheline is likely to be hot. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Kees Cook <keescook@chromium.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Vince Weaver <vince@deater.net> Cc: "hillf.zj" <hillf.zj@alibaba-inc.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/3a54dd3353fffbf84804398e00dfdc5b7c1afd7d.1414190806.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/ia32-compat: Fix CLONE_SETTLS bitness of copy_thread()Andy Lutomirski2015-02-251-1/+1
|/ | | | | | | | | | | | | | | CLONE_SETTLS is expected to write a TLS entry in the GDT for 32-bit callers and to set FSBASE for 64-bit callers. The correct check is is_ia32_task(), which returns true in the context of a 32-bit syscall. TIF_IA32 is set if the task itself has a 32-bit personality, which is not the same thing. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Link: http://lkml.kernel.org/r/45e2d0d695393d76406a0c7225b82c76223e0cc5.1424822291.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86_64, switch_to(): Load TLS descriptors before switching DS and ESAndy Lutomirski2014-12-111-28/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Otherwise, if buggy user code points DS or ES into the TLS array, they would be corrupted after a context switch. This also significantly improves the comments and documents some gotchas in the code. Before this patch, the both tests below failed. With this patch, the es test passes, although the gsbase test still fails. ----- begin es test ----- /* * Copyright (c) 2014 Andy Lutomirski * GPL v2 */ static unsigned short GDT3(int idx) { return (idx << 3) | 3; } static int create_tls(int idx, unsigned int base) { struct user_desc desc = { .entry_number = idx, .base_addr = base, .limit = 0xfffff, .seg_32bit = 1, .contents = 0, /* Data, grow-up */ .read_exec_only = 0, .limit_in_pages = 1, .seg_not_present = 0, .useable = 0, }; if (syscall(SYS_set_thread_area, &desc) != 0) err(1, "set_thread_area"); return desc.entry_number; } int main() { int idx = create_tls(-1, 0); printf("Allocated GDT index %d\n", idx); unsigned short orig_es; asm volatile ("mov %%es,%0" : "=rm" (orig_es)); int errors = 0; int total = 1000; for (int i = 0; i < total; i++) { asm volatile ("mov %0,%%es" : : "rm" (GDT3(idx))); usleep(100); unsigned short es; asm volatile ("mov %%es,%0" : "=rm" (es)); asm volatile ("mov %0,%%es" : : "rm" (orig_es)); if (es != GDT3(idx)) { if (errors == 0) printf("[FAIL]\tES changed from 0x%hx to 0x%hx\n", GDT3(idx), es); errors++; } } if (errors) { printf("[FAIL]\tES was corrupted %d/%d times\n", errors, total); return 1; } else { printf("[OK]\tES was preserved\n"); return 0; } } ----- end es test ----- ----- begin gsbase test ----- /* * gsbase.c, a gsbase test * Copyright (c) 2014 Andy Lutomirski * GPL v2 */ static unsigned char *testptr, *testptr2; static unsigned char read_gs_testvals(void) { unsigned char ret; asm volatile ("movb %%gs:%1, %0" : "=r" (ret) : "m" (*testptr)); return ret; } int main() { int errors = 0; testptr = mmap((void *)0x200000000UL, 1, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS, -1, 0); if (testptr == MAP_FAILED) err(1, "mmap"); testptr2 = mmap((void *)0x300000000UL, 1, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS, -1, 0); if (testptr2 == MAP_FAILED) err(1, "mmap"); *testptr = 0; *testptr2 = 1; if (syscall(SYS_arch_prctl, ARCH_SET_GS, (unsigned long)testptr2 - (unsigned long)testptr) != 0) err(1, "ARCH_SET_GS"); usleep(100); if (read_gs_testvals() == 1) { printf("[OK]\tARCH_SET_GS worked\n"); } else { printf("[FAIL]\tARCH_SET_GS failed\n"); errors++; } asm volatile ("mov %0,%%gs" : : "r" (0)); if (read_gs_testvals() == 0) { printf("[OK]\tWriting 0 to gs worked\n"); } else { printf("[FAIL]\tWriting 0 to gs failed\n"); errors++; } usleep(100); if (read_gs_testvals() == 0) { printf("[OK]\tgsbase is still zero\n"); } else { printf("[FAIL]\tgsbase was corrupted\n"); errors++; } return errors == 0 ? 0 : 1; } ----- end gsbase test ----- Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: <stable@vger.kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/509d27c9fec78217691c3dad91cec87e1006b34a.1418075657.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86: copy_thread: Don't nullify ->ptrace_bps twiceOleg Nesterov2014-09-021-2/+0
| | | | | | | | | Both 32bit and 64bit versions of copy_thread() do memset(ptrace_bps) twice for no reason, kill the 2nd memset(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20140902175733.GA21676@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* x86, fpu: Shift "fpu_counter = 0" from copy_thread() to arch_dup_task_struct()Oleg Nesterov2014-09-021-1/+0
| | | | | | | | | | | Cosmetic, but I think thread.fpu_counter should be initialized in arch_dup_task_struct() too, along with other "fpu" variables. And probably it make sense to turn it into thread.fpu->counter. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Link: http://lkml.kernel.org/r/20140902175730.GA21669@redhat.com Reviewed-by: Suresh Siddha <sbsiddha@gmail.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Merge branch 'perf/urgent' into perf/core, to resolve conflict and to ↵Ingo Molnar2014-06-061-1/+1
|\ | | | | | | | | | | | | | | | | prepare for new patches Conflicts: arch/x86/kernel/traps.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * asmlinkage, x86: Add explicit __visible to arch/x86/*Andi Kleen2014-05-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | As requested by Linus add explicit __visible to the asmlinkage users. This marks all functions visible to assembler. Tree sweep for arch/x86/* Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1398984278-29319-3-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | uprobes/x86: Fix is_64bit_mm() with CONFIG_X86_X32Oleg Nesterov2014-04-301-3/+4
|/ | | | | | | | | | | | | | | | is_64bit_mm() assumes that mm->context.ia32_compat means the 32-bit instruction set, this is not true if the task is TIF_X32. Change set_personality_ia32() to initialize mm->context.ia32_compat by TIF_X32 or TIF_IA32 instead of 1. This allows to fix is_64bit_mm() without affecting other users, they all treat ia32_compat as "bool". TIF_ in ->ia32_compat looks a bit strange, but this is grep-friendly and avoids the new define's. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Jim Keniston <jkenisto@us.ibm.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2013-11-141-1/+1
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull two x86 fixes from Ingo Molnar. * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/microcode/amd: Tone down printk(), don't treat a missing firmware file as an error x86/dumpstack: Fix printk_address for direct addresses
| * x86/dumpstack: Fix printk_address for direct addressesJiri Slaby2013-11-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Consider a kernel crash in a module, simulated the following way: static int my_init(void) { char *map = (void *)0x5; *map = 3; return 0; } module_init(my_init); When we turn off FRAME_POINTERs, the very first instruction in that function causes a BUG. The problem is that we print IP in the BUG report using %pB (from printk_address). And %pB decrements the pointer by one to fix printing addresses of functions with tail calls. This was added in commit 71f9e59800e5ad4 ("x86, dumpstack: Use %pB format specifier for stack trace") to fix the call stack printouts. So instead of correct output: BUG: unable to handle kernel NULL pointer dereference at 0000000000000005 IP: [<ffffffffa01ac000>] my_init+0x0/0x10 [pb173] We get: BUG: unable to handle kernel NULL pointer dereference at 0000000000000005 IP: [<ffffffffa0152000>] 0xffffffffa0151fff To fix that, we use %pS only for stack addresses printouts (via newly added printk_stack_address) and %pB for regs->ip (via printk_address). I.e. we revert to the old behaviour for all except call stacks. And since from all those reliable is 1, we remove that parameter from printk_address. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: joe@perches.com Cc: jirislaby@gmail.com Link: http://lkml.kernel.org/r/1382706418-8435-1-git-send-email-jslaby@suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86: move fpu_counter into ARCH specific thread_structVineet Gupta2013-11-131-1/+1
|/ | | | | | | | | | | | | | Only a couple of arches (sh/x86) use fpu_counter in task_struct so it can be moved out into ARCH specific thread_struct, reducing the size of task_struct for other arches. Compile tested i386_defconfig + gcc 4.7.3 Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Paul Mundt <paul.mundt@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* sched, x86: Provide a per-cpu preempt_count implementationPeter Zijlstra2013-09-251-0/+8
| | | | | | | | | | | | | | | | | | | | | | | 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>
* x86, asmlinkage: Make several variables used from assembler/linker script ↵Andi Kleen2013-08-061-1/+1
| | | | | | | | | | 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>
* x86, asmlinkage: Make 32bit/64bit __switch_to visibleAndi Kleen2013-08-061-1/+1
| | | | | | | | This function is called from inline assembler, so has to be visible. Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-6-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds2013-07-031-1/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 debug update from Ingo Molnar: "Misc debuggability improvements: - Optimize the x86 CPU register printout a bit - Expose the tboot TXT log via debugfs - Small do_debug() cleanup" * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/tboot: Provide debugfs interfaces to access TXT log x86: Remove weird PTR_ERR() in do_debug x86/debug: Only print out DR registers if they are not power-on defaults
| * x86/debug: Only print out DR registers if they are not power-on defaultsDave Jones2013-06-191-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The DR registers are rarely useful when decoding oopses. With screen real estate during oopses at a premium, we can save two lines by only printing out these registers when they are set to something other than they power-on state. Signed-off-by: Dave Jones <davej@redhat.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20130618160911.GA24487@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86, flags: Rename X86_EFLAGS_BIT1 to X86_EFLAGS_FIXEDH. Peter Anvin2013-06-261-1/+1
|/ | | | | | | | | | | | Bit 1 in the x86 EFLAGS is always set. Name the macro something that actually tries to explain what it is all about, rather than being a tautology. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Gleb Natapov <gleb@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: http://lkml.kernel.org/n/tip-f10rx5vjjm6tfnt8o1wseb3v@git.kernel.org
* dump_stack: unify debug information printed by show_regs()Tejun Heo2013-05-011-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | show_regs() is inherently arch-dependent but it does make sense to print generic debug information and some archs already do albeit in slightly different forms. This patch introduces a generic function to print debug information from show_regs() so that different archs print out the same information and it's much easier to modify what's printed. show_regs_print_info() prints out the same debug info as dump_stack() does plus task and thread_info pointers. * Archs which didn't print debug info now do. alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r, metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc, um, xtensa * Already prints debug info. Replaced with show_regs_print_info(). The printed information is superset of what used to be there. arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86 * s390 is special in that it used to print arch-specific information along with generic debug info. Heiko and Martin think that the arch-specific extra isn't worth keeping s390 specfic implementation. Converted to use the generic version. Note that now all archs print the debug info before actual register dumps. An example BUG() dump follows. kernel BUG at /work/os/work/kernel/workqueue.c:4841! invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000 RIP: 0010:[<ffffffff8234a07e>] [<ffffffff8234a07e>] init_workqueues+0x4/0x6 RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Stack: ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650 0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760 Call Trace: [<ffffffff81000312>] do_one_initcall+0x122/0x170 [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8 [<ffffffff81c47760>] ? rest_init+0x140/0x140 [<ffffffff81c4776e>] kernel_init+0xe/0xf0 [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0 [<ffffffff81c47760>] ? rest_init+0x140/0x140 ... v2: Typo fix in x86-32. v3: CPU number dropped from show_regs_print_info() as dump_stack_print_info() has been updated to print it. s390 specific implementation dropped as requested by s390 maintainers. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Fengguang Wu <fengguang.wu@intel.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Sam Ravnborg <sam@ravnborg.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [tile bits] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86/process: Change %8s to %s for pr_warn() in release_thread()Chen Gang2013-01-241-1/+1
| | | | | | | | | | | | | | | | | | | the length of dead_task->comm[] is 16 (TASK_COMM_LEN) on pr_warn(), it is not meaningful to use %8s for task->comm[]. So change it to %s, since the line is not solid anyway. Additional information: %8s limit the width, not for the original string output length if name length is more than 8, it still can be fully displayed. if name length is less than 8, the ' ' will be filled before name. %.8s truly limit the original string output length (precision) Signed-off-by: Chen Gang <gang.chen@asianux.com> Link: http://lkml.kernel.org/n/tip-nridm1zvreai1tgfLjuexDmd@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* flagday: don't pass regs to copy_thread()Al Viro2012-11-291-2/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* x86, um: switch to generic fork/vfork/cloneAl Viro2012-11-291-3/+4
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for-linus' of ↵Linus Torvalds2012-10-101-14/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull generic execve() changes from Al Viro: "This introduces the generic kernel_thread() and kernel_execve() functions, and switches x86, arm, alpha, um and s390 over to them." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (26 commits) s390: convert to generic kernel_execve() s390: switch to generic kernel_thread() s390: fold kernel_thread_helper() into ret_from_fork() s390: fold execve_tail() into start_thread(), convert to generic sys_execve() um: switch to generic kernel_thread() x86, um/x86: switch to generic sys_execve and kernel_execve x86: split ret_from_fork alpha: introduce ret_from_kernel_execve(), switch to generic kernel_execve() alpha: switch to generic kernel_thread() alpha: switch to generic sys_execve() arm: get rid of execve wrapper, switch to generic execve() implementation arm: optimized current_pt_regs() arm: introduce ret_from_kernel_execve(), switch to generic kernel_execve() arm: split ret_from_fork, simplify kernel_thread() [based on patch by rmk] generic sys_execve() generic kernel_execve() new helper: current_pt_regs() preparation for generic kernel_thread() um: kill thread->forking um: let signal_delivered() do SIGTRAP on singlestepping into handler ...
| * x86: split ret_from_forkAl Viro2012-10-011-14/+21
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | x86, fpu: use non-lazy fpu restore for processors supporting xsaveSuresh Siddha2012-09-191-4/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fundamental model of the current Linux kernel is to lazily init and restore FPU instead of restoring the task state during context switch. This changes that fundamental lazy model to the non-lazy model for the processors supporting xsave feature. Reasons driving this model change are: i. Newer processors support optimized state save/restore using xsaveopt and xrstor by tracking the INIT state and MODIFIED state during context-switch. This is faster than modifying the cr0.TS bit which has serializing semantics. ii. Newer glibc versions use SSE for some of the optimized copy/clear routines. With certain workloads (like boot, kernel-compilation etc), application completes its work with in the first 5 task switches, thus taking upto 5 #DNA traps with the kernel not getting a chance to apply the above mentioned pre-load heuristic. iii. Some xstate features (like AMD's LWP feature) don't honor the cr0.TS bit and thus will not work correctly in the presence of lazy restore. Non-lazy state restore is needed for enabling such features. Some data on a two socket SNB system: * Saved 20K DNA exceptions during boot on a two socket SNB system. * Saved 50K DNA exceptions during kernel-compilation workload. * Improved throughput of the AVX based checksumming function inside the kernel by ~15% as xsave/xrstor is faster than the serializing clts/stts pair. Also now kernel_fpu_begin/end() relies on the patched alternative instructions. So move check_fpu() which uses the kernel_fpu_begin/end() after alternative_instructions(). Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1345842782-24175-7-git-send-email-suresh.b.siddha@intel.com Merge 32-bit boot fix from, Link: http://lkml.kernel.org/r/1347300665-6209-4-git-send-email-suresh.b.siddha@intel.com Cc: Jim Kukunas <james.t.kukunas@linux.intel.com> Cc: NeilBrown <neilb@suse.de> Cc: Avi Kivity <avi@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* Merge branch 'x86-debug-for-linus' of ↵Linus Torvalds2012-07-221-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull debug-for-linus git tree from Ingo Molnar. Fix up trivial conflict in arch/x86/kernel/cpu/perf_event_intel.c due to a printk() having changed to a pr_info() differently in the two branches. * 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Move call to print_modules() out of show_regs() x86/mm: Mark free_initrd_mem() as __init x86/microcode: Mark microcode_id[] as __initconst x86/nmi: Clean up register_nmi_handler() usage x86: Save cr2 in NMI in case NMIs take a page fault (for i386) x86: Remove cmpxchg from i386 NMI nesting code x86: Save cr2 in NMI in case NMIs take a page fault x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>
| * x86/debug: Add KERN_<LEVEL> to bare printks, convert printks to pr_<level>Joe Perches2012-06-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use a more current logging style: - Bare printks should have a KERN_<LEVEL> for consistency's sake - Add pr_fmt where appropriate - Neaten some macro definitions - Convert some Ok output to OK - Use "%s: ", __func__ in pr_fmt for summit - Convert some printks to pr_<level> Message output is not identical in all cases. Signed-off-by: Joe Perches <joe@perches.com> Cc: levinsasha928@gmail.com Link: http://lkml.kernel.org/r/1337655007.24226.10.camel@joe2Laptop [ merged two similar patches, tidied up the changelog ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86, cpu: Rename checking_wrmsrl() to wrmsrl_safe()H. Peter Anvin2012-06-071-2/+2
|/ | | | | | | Rename checking_wrmsrl() to wrmsrl_safe(), to match the naming convention used by all the other MSR access functions/macros. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds2012-05-231-9/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull fpu state cleanups from Ingo Molnar: "This tree streamlines further aspects of FPU handling by eliminating the prepare_to_copy() complication and moving that logic to arch_dup_task_struct(). It also fixes the FPU dumps in threaded core dumps, removes and old (and now invalid) assumption plus micro-optimizes the exit path by avoiding an FPU save for dead tasks." Fixed up trivial add-add conflict in arch/sh/kernel/process.c that came in because we now do the FPU handling in arch_dup_task_struct() rather than the legacy (and now gone) prepare_to_copy(). * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, fpu: drop the fpu state during thread exit x86, xsave: remove thread_has_fpu() bug check in __sanitize_i387_state() coredump: ensure the fpu state is flushed for proper multi-threaded core dump fork: move the real prepare_to_copy() users to arch_dup_task_struct()
| * fork: move the real prepare_to_copy() users to arch_dup_task_struct()Suresh Siddha2012-05-171-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Historical prepare_to_copy() is mostly a no-op, duplicated for majority of the architectures and the rest following the x86 model of flushing the extended register state like fpu there. Remove it and use the arch_dup_task_struct() instead. Suggested-by: Oleg Nesterov <oleg@redhat.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Link: http://lkml.kernel.org/r/1336692811-30576-1-git-send-email-suresh.b.siddha@intel.com Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Zankel <chris@zankel.net> Cc: Richard Henderson <rth@twiddle.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Mark Salter <msalter@redhat.com> Cc: Aurelien Jacquiot <a-jacquiot@ti.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Michal Simek <monstr@monstr.eu> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: Lennox Wu <lennox.wu@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
* | x86: replace percpu_xxx funcs with this_cpu_xxxAlex Shi2012-05-141-5/+5
|/ | | | | | | | | | | | | | | | | | | | | | | | | | Since percpu_xxx() serial functions are duplicated with this_cpu_xxx(). Removing percpu_xxx() definition and replacing them by this_cpu_xxx() in code. There is no function change in this patch, just preparation for later percpu_xxx serial function removing. On x86 machine the this_cpu_xxx() serial functions are same as __this_cpu_xxx() without no unnecessary premmpt enable/disable. Thanks for Stephen Rothwell, he found and fixed a i386 build error in the patch. Also thanks for Andrew Morton, he kept updating the patchset in Linus' tree. Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: Christoph Lameter <cl@gentwo.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* IA32 emulation: Fix build problem for modular ia32 a.out supportLarry Finger2012-05-071-0/+1
| | | | | | | | | | | | | | Commit ce7e5d2d19bc ("x86: fix broken TASK_SIZE for ia32_aout") breaks kernel builds when "CONFIG_IA32_AOUT=m" with ERROR: "set_personality_ia32" [arch/x86/ia32/ia32_aout.ko] undefined! make[1]: *** [__modpost] Error 1 The entry point needs to be exported. Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Acked-by: Al Viro <viro@zeniv.linux.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'x86-x32-for-linus' of ↵Linus Torvalds2012-03-301-6/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x32 support for x86-64 from Ingo Molnar: "This tree introduces the X32 binary format and execution mode for x86: 32-bit data space binaries using 64-bit instructions and 64-bit kernel syscalls. This allows applications whose working set fits into a 32 bits address space to make use of 64-bit instructions while using a 32-bit address space with shorter pointers, more compressed data structures, etc." Fix up trivial context conflicts in arch/x86/{Kconfig,vdso/vma.c} * 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits) x32: Fix alignment fail in struct compat_siginfo x32: Fix stupid ia32/x32 inversion in the siginfo format x32: Add ptrace for x32 x32: Switch to a 64-bit clock_t x32: Provide separate is_ia32_task() and is_x32_task() predicates x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls x86/x32: Fix the binutils auto-detect x32: Warn and disable rather than error if binutils too old x32: Only clear TIF_X32 flag once x32: Make sure TS_COMPAT is cleared for x32 tasks fs: Remove missed ->fds_bits from cessation use of fd_set structs internally fs: Fix close_on_exec pointer in alloc_fdtable x32: Drop non-__vdso weak symbols from the x32 VDSO x32: Fix coding style violations in the x32 VDSO code x32: Add x32 VDSO support x32: Allow x32 to be configured x32: If configured, add x32 system calls to system call tables x32: Handle process creation x32: Signal-related system calls x86: Add #ifdef CONFIG_COMPAT to <asm/sys_ia32.h> ...
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