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2018-07-20x86/pgtable/32: Allocate 8k page-tables when PTI is enabledJoerg Roedel1-5/+15
Allocate a kernel and a user page-table root when PTI is enabled. Also allocate a full page per root for PAE because otherwise the bit to flip in CR3 to switch between them would be non-constant, which creates a lot of hassle. Keep that for a later optimization. Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Pavel Machek <pavel@ucw.cz> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: linux-mm@kvack.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Laight <David.Laight@aculab.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Eduardo Valentin <eduval@amazon.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Will Deacon <will.deacon@arm.com> Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Waiman Long <llong@redhat.com> Cc: "David H . Gutteridge" <dhgutteridge@sympatico.ca> Cc: joro@8bytes.org Link: https://lkml.kernel.org/r/1531906876-13451-18-git-send-email-joro@8bytes.org
2018-06-14Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variablesLinus Torvalds1-1/+1
The changes to automatically test for working stack protector compiler support in the Kconfig files removed the special STACKPROTECTOR_AUTO option that picked the strongest stack protector that the compiler supported. That was all a nice cleanup - it makes no sense to have the AUTO case now that the Kconfig phase can just determine the compiler support directly. HOWEVER. It also meant that doing "make oldconfig" would now _disable_ the strong stackprotector if you had AUTO enabled, because in a legacy config file, the sane stack protector configuration would look like CONFIG_HAVE_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_NONE is not set # CONFIG_CC_STACKPROTECTOR_REGULAR is not set # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_STACKPROTECTOR_AUTO=y and when you ran this through "make oldconfig" with the Kbuild changes, it would ask you about the regular CONFIG_CC_STACKPROTECTOR (that had been renamed from CONFIG_CC_STACKPROTECTOR_REGULAR to just CONFIG_CC_STACKPROTECTOR), but it would think that the STRONG version used to be disabled (because it was really enabled by AUTO), and would disable it in the new config, resulting in: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_CC_STACKPROTECTOR=y # CONFIG_CC_STACKPROTECTOR_STRONG is not set CONFIG_CC_HAS_SANE_STACKPROTECTOR=y That's dangerously subtle - people could suddenly find themselves with the weaker stack protector setup without even realizing. The solution here is to just rename not just the old RECULAR stack protector option, but also the strong one. This does that by just removing the CC_ prefix entirely for the user choices, because it really is not about the compiler support (the compiler support now instead automatially impacts _visibility_ of the options to users). This results in "make oldconfig" actually asking the user for their choice, so that we don't have any silent subtle security model changes. The end result would generally look like this: CONFIG_HAVE_CC_STACKPROTECTOR=y CONFIG_CC_HAS_STACKPROTECTOR_NONE=y CONFIG_STACKPROTECTOR=y CONFIG_STACKPROTECTOR_STRONG=y CONFIG_CC_HAS_SANE_STACKPROTECTOR=y where the "CC_" versions really are about internal compiler infrastructure, not the user selections. Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-15x86/cpu: Rename cpu_data.x86_mask to cpu_data.x86_steppingJia Zhang1-2/+2
x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. Signed-off-by: Jia Zhang <qianyue.zj@alibaba-inc.com> [ Updated it to more recent kernels. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17Merge commit 'upstream-x86-entry' into WIP.x86/mmIngo Molnar1-4/+1
Pull in a minimal set of v4.15 entry code changes, for a base for the MM isolation patches. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02Merge branch 'x86/mpx/prep' into x86/asmIngo Molnar1-3/+0
Pick up some of the MPX commits that modify the syscall entry code, to have a common base and to reduce conflicts. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-01x86/boot: Relocate definition of the initial state of CR0Ricardo Neri1-3/+0
Both head_32.S and head_64.S utilize the same value to initialize the control register CR0. Also, other parts of the kernel might want to access this initial definition (e.g., emulation code for User-Mode Instruction Prevention uses this state to provide a sane dummy value for CR0 when emulating the smsw instruction). Thus, relocate this definition to a header file from which it can be conveniently accessed. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: ricardo.neri@intel.com Cc: linux-mm@kvack.org Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Huang Rui <ray.huang@amd.com> Cc: Shuah Khan <shuah@kernel.org> Cc: linux-arch@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jiri Slaby <jslaby@suse.cz> Cc: "Ravi V. Shankar" <ravi.v.shankar@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/1509135945-13762-3-git-send-email-ricardo.neri-calderon@linux.intel.com
2017-10-23x86/asm: Don't use the confusing '.ifeq' directiveJosh Poimboeuf1-1/+1
I find the '.ifeq <expression>' directive to be confusing. Reading it quickly seems to suggest its opposite meaning, or that it's missing an argument. Improve readability by replacing all of its x86 uses with '.if <expression> == 0'. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrei Vagin <avagin@virtuozzo.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/757da028e802c7e98d23fbab8d234b1063e161cf.1508516398.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-31x86/idt: Remove superfluous ALIGNmentJiri Slaby1-1/+1
Commit 87e81786b13b ("x86/idt: Move early IDT setup out of 32-bit asm") switched early_ignore_irq to use ENTRY. ENTRY aligns the code, so there is no need for one more ALIGN right before the function. And add one \n after the function to separate it from the data. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Link: http://lkml.kernel.org/r/20170831121653.28917-1-jslaby@suse.cz
2017-08-29x86/idt: Move early IDT setup out of 32-bit asmThomas Gleixner1-34/+2
The early IDT setup can be done in C code like it's done on 64-bit kernels. Reuse the 64-bit version. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064958.757980775@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29x86/idt: Move 32-bit idt_descr to C codeThomas Gleixner1-6/+0
32-bit kernels have the idt_descr defined in the low level assembly entry code, but there is no good reason for that. Move it into the C file and use the 64-bit version of it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064958.445862201@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-24x86/lguest: Remove lguest supportJuergen Gross1-2/+0
Lguest seems to be rather unused these days. It has seen only patches ensuring it still builds the last two years and its official state is "Odd Fixes". Remove it in order to be able to clean up the paravirt code. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: boris.ostrovsky@oracle.com Cc: lguest@lists.ozlabs.org Cc: rusty@rustcorp.com.au Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-30x86/traps: Don't clear segment high bits in early_idt_handler_common()Andy Lutomirski1-12/+8
Now that pt_regs defines the segment fields as 16-bit, there's no need to sanitize the values. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bpetkov@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-06x86/boot/32: Convert the 32-bit pgtable setup code from assembly to CBoris Ostrovsky1-114/+7
The new Xen PVH entry point requires page tables to be setup by the kernel since it is entered with paging disabled. Pull the common code out of head_32.S so that mk_early_pgtbl_32() can be invoked from both the new Xen entry point and the existing startup_32() code. Convert resulting common code to C. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: matt@codeblueprint.co.uk Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1481215471-9639-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-12Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds1-20/+29
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this development cycle were: - a large number of call stack dumping/printing improvements: higher robustness, better cross-context dumping, improved output, etc. (Josh Poimboeuf) - vDSO getcpu() performance improvement for future Intel CPUs with the RDPID instruction (Andy Lutomirski) - add two new Intel AVX512 features and the CPUID support infrastructure for it: AVX512IFMA and AVX512VBMI. (Gayatri Kammela, He Chen) - more copy-user unification (Borislav Petkov) - entry code assembly macro simplifications (Alexander Kuleshov) - vDSO C/R support improvements (Dmitry Safonov) - misc fixes and cleanups (Borislav Petkov, Paul Bolle)" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) scripts/decode_stacktrace.sh: Fix address line detection on x86 x86/boot/64: Use defines for page size x86/dumpstack: Make stack name tags more comprehensible selftests/x86: Add test_vdso to test getcpu() x86/vdso: Use RDPID in preference to LSL when available x86/dumpstack: Handle NULL stack pointer in show_trace_log_lvl() x86/cpufeatures: Enable new AVX512 cpu features x86/cpuid: Provide get_scattered_cpuid_leaf() x86/cpuid: Cleanup cpuid_regs definitions x86/copy_user: Unify the code by removing the 64-bit asm _copy_*_user() variants x86/unwind: Ensure stack grows down x86/vdso: Set vDSO pointer only after success x86/prctl/uapi: Remove #ifdef for CHECKPOINT_RESTORE x86/unwind: Detect bad stack return address x86/dumpstack: Warn on stack recursion x86/unwind: Warn on bad frame pointer x86/decoder: Use stderr if insn sanity test fails x86/decoder: Use stdout if insn decoder test is successful mm/page_alloc: Remove kernel address exposure in free_reserved_area() x86/dumpstack: Remove raw stack dump ...
2016-11-17x86/boot: Avoid warning for zero-filling .bssArnd Bergmann1-3/+6
The latest binutils are warning about a .fill directive with an explicit value in a .bss section: arch/x86/kernel/head_32.S: Assembler messages: arch/x86/kernel/head_32.S:677: Warning: ignoring fill value in section `.bss..page_aligned' arch/x86/kernel/head_32.S:679: Warning: ignoring fill value in section `.bss..page_aligned' This comes from the 'ENTRY()' macro padding the space between the symbols with 'nop' via: .align 4,0x90 Open-coding the .globl directive without the padding avoids that warning, as all the symbols are already page aligned. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161116141726.2013389-1-arnd@arndb.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-20x86/boot: Fix the end of the stack for idle tasksJosh Poimboeuf1-1/+8
Thanks to all the recent x86 entry code refactoring, most tasks' kernel stacks start at the same offset right below their saved pt_regs, regardless of which syscall was used to enter the kernel. That creates a nice convention which makes it straightforward to identify the end of the stack, which can be useful for the unwinder to verify the stack is sane. However, the boot CPU's idle "swapper" task doesn't follow that convention. Fix that by starting its stack at a sizeof(pt_regs) offset from the end of the stack page. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/81aee3beb6ed88e44f1bea6986bb7b65c368f77a.1474480779.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-20x86/boot/32: Fix the end of the stack for idle tasksJosh Poimboeuf1-3/+5
The frame at the end of each idle task stack is inconsistent with real task stacks, which have a stack frame header and a real return address before the pt_regs area. This inconsistency can be confusing for stack unwinders. It also hides useful information about what asm code was involved in calling into C. Fix that by changing the initial code jumps to calls. Also add infinite loops after the calls to make it clear that the calls don't return, and to hang if they do. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2588f34b6fbac4ae6f6f9ead2a78d7f8d58a6341.1474480779.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-20x86/entry/32, x86/boot/32: Use local labelsJosh Poimboeuf1-16/+16
Add the local label prefix to all non-function named labels in head_32.S and entry_32.S. In addition to decluttering the symbol table, it also will help stack traces to be more sensible. For example, the last reported function in the idle task stack trace will be startup_32_smp() instead of is486(). Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/14f9f7afd478b23a762f40734da1a57c0c273f6e.1474480779.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-14Merge branch 'kbuild' of ↵Linus Torvalds1-0/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - EXPORT_SYMBOL for asm source by Al Viro. This does bring a regression, because genksyms no longer generates checksums for these symbols (CONFIG_MODVERSIONS). Nick Piggin is working on a patch to fix this. Plus, we are talking about functions like strcpy(), which rarely change prototypes. - Fixes for PPC fallout of the above by Stephen Rothwell and Nick Piggin - fixdep speedup by Alexey Dobriyan. - preparatory work by Nick Piggin to allow architectures to build with -ffunction-sections, -fdata-sections and --gc-sections - CONFIG_THIN_ARCHIVES support by Stephen Rothwell - fix for filenames with colons in the initramfs source by me. * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (22 commits) initramfs: Escape colons in depfile ppc: there is no clear_pages to export powerpc/64: whitelist unresolved modversions CRCs kbuild: -ffunction-sections fix for archs with conflicting sections kbuild: add arch specific post-link Makefile kbuild: allow archs to select link dead code/data elimination kbuild: allow architectures to use thin archives instead of ld -r kbuild: Regenerate genksyms lexer kbuild: genksyms fix for typeof handling fixdep: faster CONFIG_ search ia64: move exports to definitions sparc32: debride memcpy.S a bit [sparc] unify 32bit and 64bit string.h sparc: move exports to definitions ppc: move exports to definitions arm: move exports to definitions s390: move exports to definitions m68k: move exports to definitions alpha: move exports to actual definitions x86: move exports to actual definitions ...
2016-08-18x86/asm/head: Rename 'stack_start' -> 'initial_stack'Josh Poimboeuf1-4/+4
The 'stack_start' variable is similar in usage to 'initial_code' and 'initial_gs': they're all stored in head_64.S and they're all updated by SMP and ACPI suspend before starting a CPU. Rename it to 'initial_stack' to be consistent with the others. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Byungchul Park <byungchul.park@lge.com> 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: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/87063d773a3212051b77e17b0ee427f6582a5050.1471535549.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-07x86: move exports to actual definitionsAl Viro1-0/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-29Merge branch 'x86/urgent' into x86/asm, to refresh the treeIngo Molnar1-6/+0
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-26Revert "x86/mm/32: Set NX in __supported_pte_mask before enabling paging"Andy Lutomirski1-6/+0
This reverts commit 320d25b6a05f8b73c23fc21025d2906ecdd2d4fc. This change was problematic for a couple of reasons: 1. It missed a some entry points (Xen things and 64-bit native). 2. The entry it changed can be executed more than once. This isn't really a problem, but it conflated per-cpu state setup and global state setup. 3. It broke 64-bit non-NX. 64-bit non-NX worked the other way around from 32-bit -- __supported_pte_mask had NX set initially and was *cleared* in x86_configure_nx. With the patch applied, it never got cleared. Reported-and-tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/59bd15f7f4b56b633a611b7f70876c6d2ad01a98.1461685884.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13x86/head: Move early exception panic code into early_fixup_exception()Andy Lutomirski1-44/+5
This removes a bunch of assembly and adds some C code instead. It changes the actual printouts on both 32-bit and 64-bit kernels, but they still seem okay. Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: KVM list <kvm@vger.kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel <Xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/4085070316fc3ab29538d3fcfe282648d1d4ee2e.1459605520.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13x86/head: Move the early NMI fixup into CAndy Lutomirski1-7/+0
C is nicer than asm. Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: KVM list <kvm@vger.kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel <Xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/dd068269f8d59fe44e9e43a50d0efd67da65c2b5.1459605520.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13x86/head: Pass a real pt_regs and trapnr to early_fixup_exception()Andy Lutomirski1-23/+51
early_fixup_exception() is limited by the fact that it doesn't have a real struct pt_regs. Change both the 32-bit and 64-bit asm and the C code to pass and accept a real pt_regs. Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: KVM list <kvm@vger.kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: xen-devel <Xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/e3fb680fcfd5e23e38237e8328b64a25cc121d37.1459605520.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-15Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: "The main changes in this cycle were: - Enable full ASLR randomization for 32-bit programs (Hector Marco-Gisbert) - Add initial minimal INVPCI support, to flush global mappings (Andy Lutomirski) - Add KASAN enhancements (Andrey Ryabinin) - Fix mmiotrace for huge pages (Karol Herbst) - ... misc cleanups and small enhancements" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm/32: Enable full randomization on i386 and X86_32 x86/mm/kmmio: Fix mmiotrace for hugepages x86/mm: Avoid premature success when changing page attributes x86/mm/ptdump: Remove paravirt_enabled() x86/mm: Fix INVPCID asm constraint x86/dmi: Switch dmi_remap() from ioremap() [uncached] to ioremap_cache() x86/mm: If INVPCID is available, use it to flush global mappings x86/mm: Add a 'noinvpcid' boot option to turn off INVPCID x86/mm: Add INVPCID helpers x86/kasan: Write protect kasan zero shadow x86/kasan: Clear kasan_zero_page after TLB flush x86/mm/numa: Check for failures in numa_clear_kernel_node_hotplug() x86/mm/numa: Clean up numa_clear_kernel_node_hotplug() x86/mm: Make kmap_prot into a #define x86/mm/32: Set NX in __supported_pte_mask before enabling paging x86/mm: Streamline and restore probe_memory_block_size()
2016-01-30x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov1-1/+1
Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-20x86/mm/32: Set NX in __supported_pte_mask before enabling pagingAndy Lutomirski1-0/+6
There's a short window in which very early mappings can end up with NX clear because they are created before we've noticed that we have NX. It turns out that we detect NX very early, so there's no need to defer __supported_pte_mask setup. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2b544627345f7110160545a3f47031eb45c3ad4f.1453239349.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-21x86/microcode: Merge the early microcode loaderBorislav Petkov1-3/+2
Merge the early loader functionality into the driver proper. The diff is huge but logically, it is simply moving code from the _early.c files into the main driver. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/1445334889-300-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-22Merge branch 'x86-core-for-linus' of ↵Linus Torvalds1-2/+2
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() ...
2015-06-19x86/boot: Fix overflow warning with 32-bit binutilsBorislav Petkov1-3/+10
When building the kernel with 32-bit binutils built with support only for the i386 target, we get the following warning: arch/x86/kernel/head_32.S:66: Warning: shift count out of range (32 is not between 0 and 31) The problem is that in that case, binutils' internal type representation is 32-bit wide and the shift range overflows. In order to fix this, manipulate the shift expression which creates the 4GiB constant to not overflow the shift count. Suggested-by: Michael Matz <matz@suse.de> Reported-and-tested-by: Enrico Mioso <mrkiko.rs@gmail.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-02x86/asm/irq: Stop relying on magic JMP behavior for early_idt_handlersAndy Lutomirski1-15/+18
The early_idt_handlers asm code generates an array of entry points spaced nine bytes apart. It's not really clear from that code or from the places that reference it what's going on, and the code only works in the first place because GAS never generates two-byte JMP instructions when jumping to global labels. Clean up the code to generate the correct array stride (member size) explicitly. This should be considerably more robust against screw-ups, as GAS will warn if a .fill directive has a negative count. Using '. =' to advance would have been even more robust (it would generate an actual error if it tried to move backwards), but it would pad with nulls, confusing anyone who tries to disassemble the code. The new scheme should be much clearer to future readers. While we're at it, improve the comments and rename the array and common code. Binutils may start relaxing jumps to non-weak labels. If so, this change will fix our build, and we may need to backport this change. Before, on x86_64: 0000000000000000 <early_idt_handlers>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 00 00 00 00 jmpq 9 <early_idt_handlers+0x9> 5: R_X86_64_PC32 early_idt_handler-0x4 ... 48: 66 90 xchg %ax,%ax 4a: 6a 08 pushq $0x8 4c: e9 00 00 00 00 jmpq 51 <early_idt_handlers+0x51> 4d: R_X86_64_PC32 early_idt_handler-0x4 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: e9 00 00 00 00 jmpq 120 <early_idt_handler> 11c: R_X86_64_PC32 early_idt_handler-0x4 After: 0000000000000000 <early_idt_handler_array>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 14 01 00 00 jmpq 11d <early_idt_handler_common> ... 48: 6a 08 pushq $0x8 4a: e9 d1 00 00 00 jmpq 120 <early_idt_handler_common> 4f: cc int3 50: cc int3 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: eb 03 jmp 120 <early_idt_handler_common> 11d: cc int3 11e: cc int3 11f: cc int3 Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Binutils <binutils@sourceware.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/ac027962af343b0c599cbfcf50b945ad2ef3d7a8.1432336324.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-24x86/asm/irq: Stop relying on magic JMP behavior for early_idt_handlersAndy Lutomirski1-15/+18
The early_idt_handlers asm code generates an array of entry points spaced nine bytes apart. It's not really clear from that code or from the places that reference it what's going on, and the code only works in the first place because GAS never generates two-byte JMP instructions when jumping to global labels. Clean up the code to generate the correct array stride (member size) explicitly. This should be considerably more robust against screw-ups, as GAS will warn if a .fill directive has a negative count. Using '. =' to advance would have been even more robust (it would generate an actual error if it tried to move backwards), but it would pad with nulls, confusing anyone who tries to disassemble the code. The new scheme should be much clearer to future readers. While we're at it, improve the comments and rename the array and common code. Binutils may start relaxing jumps to non-weak labels. If so, this change will fix our build, and we may need to backport this change. Before, on x86_64: 0000000000000000 <early_idt_handlers>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 00 00 00 00 jmpq 9 <early_idt_handlers+0x9> 5: R_X86_64_PC32 early_idt_handler-0x4 ... 48: 66 90 xchg %ax,%ax 4a: 6a 08 pushq $0x8 4c: e9 00 00 00 00 jmpq 51 <early_idt_handlers+0x51> 4d: R_X86_64_PC32 early_idt_handler-0x4 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: e9 00 00 00 00 jmpq 120 <early_idt_handler> 11c: R_X86_64_PC32 early_idt_handler-0x4 After: 0000000000000000 <early_idt_handler_array>: 0: 6a 00 pushq $0x0 2: 6a 00 pushq $0x0 4: e9 14 01 00 00 jmpq 11d <early_idt_handler_common> ... 48: 6a 08 pushq $0x8 4a: e9 d1 00 00 00 jmpq 120 <early_idt_handler_common> 4f: cc int3 50: cc int3 ... 117: 6a 00 pushq $0x0 119: 6a 1f pushq $0x1f 11b: eb 03 jmp 120 <early_idt_handler_common> 11d: cc int3 11e: cc int3 11f: cc int3 Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Binutils <binutils@sourceware.org> Cc: Borislav Petkov <bp@alien8.de> Cc: H.J. Lu <hjl.tools@gmail.com> Cc: Jan Beulich <JBeulich@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/ac027962af343b0c599cbfcf50b945ad2ef3d7a8.1432336324.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-17x86/asm/head*.S: Change global labels to localBorislav Petkov1-2/+2
Make the disassembly look less confusing: -- head_64.o.before.asm ++ head_64.o.after.asm 0000000000000120 <early_idt_handler>: 120: fc cld 121: 83 3c 24 02 cmpl $0x2,(%rsp) - 125: 0f 84 9d 00 00 00 je 1c8 <is_nmi> + 125: 0f 84 9d 00 00 00 je 1c8 <early_idt_handler+0xa8> 12b: 83 3d 00 00 00 00 02 cmpl $0x2,0x0(%rip) # 132 <early_idt_handler+0x12> 132: 74 7e je 1b2 <early_idt_handler+0x92> 134: ff 05 00 00 00 00 incl 0x0(%rip) # 13a <early_idt_handler+0x1a> @@ -1198,9 +1198,7 @@ Disassembly of section .init.text: 1bf: 5a pop %rdx 1c0: 59 pop %rcx 1c1: 58 pop %rax - 1c2: ff 0d 00 00 00 00 decl 0x0(%rip) # 1c8 <is_nmi> - -00000000000001c8 <is_nmi>: + 1c2: ff 0d 00 00 00 00 decl 0x0(%rip) # 1c8 <early_idt_handler+0xa8> 1c8: 48 83 c4 10 add $0x10,%rsp 1cc: 48 cf iretq -- head_32.o.before.asm ++ head_32.o.after.asm 0000016c <early_idt_handler>: 16c: fc cld 16d: 83 3c 24 02 cmpl $0x2,(%esp) - 171: 74 73 je 1e6 <is_nmi> + 171: 74 73 je 1e6 <ex_entry+0xc> 173: 36 83 3d 00 00 00 00 cmpl $0x2,%ss:0x0 17a: 02 17b: 74 5a je 1d7 <hlt_loop> @@ -483,8 +483,6 @@ Disassembly of section .init.text: 1dd: 59 pop %ecx 1de: 58 pop %eax 1df: 36 ff 0d 00 00 00 00 decl %ss:0x0 - -000001e6 <is_nmi>: 1e6: 83 c4 08 add $0x8,%esp 1e9: cf iret 1ea: 66 90 xchg %ax,%ax No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1431793079-11153-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-19x86/asm/boot: Use already defined KEEP_SEGMENTS macro in head_{32,64}.SAlexander Kuleshov1-1/+2
There is already defined macro KEEP_SEGMENTS in <asm/bootparam.h>, let's use it instead of hardcoded constants. Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1424331298-7456-1-git-send-email-kuleshovmail@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-03-07x86: fix compile error due to X86_TRAP_NMI use in asm filesLinus Torvalds1-1/+1
It's an enum, not a #define, you can't use it in asm files. Introduced in commit 5fa10196bdb5 ("x86: Ignore NMIs that come in during early boot"), and sadly I didn't compile-test things like I should have before pushing out. My weak excuse is that the x86 tree generally doesn't introduce stupid things like this (and the ARM pull afterwards doesn't cause me to do a compile-test either, since I don't cross-compile). Cc: Don Zickus <dzickus@redhat.com> Cc: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-07x86: Ignore NMIs that come in during early bootH. Peter Anvin1-1/+6
Don Zickus reports: A customer generated an external NMI using their iLO to test kdump worked. Unfortunately, the machine hung. Disabling the nmi_watchdog made things work. I speculated the external NMI fired, caused the machine to panic (as expected) and the perf NMI from the watchdog came in and was latched. My guess was this somehow caused the hang. ---- It appears that the latched NMI stays latched until the early page table generation on 64 bits, which causes exceptions to happen which end in IRET, which re-enable NMI. Therefore, ignore NMIs that come in during early execution, until we have proper exception handling. Reported-and-tested-by: Don Zickus <dzickus@redhat.com> Link: http://lkml.kernel.org/r/1394221143-29713-1-git-send-email-dzickus@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: <stable@vger.kernel.org> # v3.5+, older with some backport effort
2013-09-04Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu feature fixes from Ingo Molnar: "Two small cpufeature support updates" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Fix override new_cpu_data.x86 with 486 x86, cpufeature: Use new CC_HAVE_ASM_GOTO
2013-07-14x86: delete __cpuinit usage from all x86 filesPaul Gortmaker1-1/+0
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>
2013-06-28x86: Fix override new_cpu_data.x86 with 486Wang YanQing1-1/+1
We should set X86 to 486 before use cpuid to detect the cpu type, if we set X86 to 486 after cpuid, then we will get 486 until cpu_detect runs. Signed-off-by: Wang YanQing <udknight@gmail.com> Link: http://lkml.kernel.org/r/20130628144516.GA2177@udknight Acked-by: Borislav Petkov <bp@suse.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 Anvin1-21/+0
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>
2013-02-22Merge branch 'x86/microcode' of ↵Linus Torvalds1-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode loading update from Peter Anvin: "This patchset lets us update the CPU microcode very, very early in initialization if the BIOS fails to do so (never happens, right?) This is handy for dealing with things like the Atom erratum where we have to run without PSE because microcode loading happens too late. As I mentioned in the x86/mm push request it depends on that infrastructure but it is otherwise a standalone feature." * 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/Kconfig: Make early microcode loading a configuration feature x86/mm/init.c: Copy ucode from initrd image to kernel memory x86/head64.c: Early update ucode in 64-bit x86/head_32.S: Early update ucode in 32-bit x86/microcode_intel_early.c: Early update ucode on Intel's CPU x86/tlbflush.h: Define __native_flush_tlb_global_irq_disabled() x86/microcode_intel_lib.c: Early update ucode on Intel's CPU x86/microcode_core_early.c: Define interfaces for early loading ucode x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on AP x86/common.c: Make have_cpuid_p() a global function x86/microcode_intel.h: Define functions and macros for early loading ucode x86, doc: Documentation for early microcode loading
2013-02-12x86, head_32: Give the 6 label a real nameBorislav Petkov1-6/+6
Jumping here we are about to enable paging so rename the label accordingly. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1360592538-10643-5-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-12x86, head_32: Remove second CPUID detection from default_entryBorislav Petkov1-13/+4
We do that once earlier now and cache it into new_cpu_data.cpuid_level so no need for the EFLAGS.ID toggling dance anymore. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1360592538-10643-4-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-12x86: Detect CPUID support early at bootBorislav Petkov1-25/+25
We detect CPUID function support on each CPU and save it for later use, obviating the need to play the toggle EFLAGS.ID game every time. C code is looking at ->cpuid_level anyway. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1360592538-10643-3-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-02-12x86, head_32: Remove i386 piecesBorislav Petkov1-17/+5
Remove code fragments detecting a 386 CPU since we don't support those anymore. Also, do not do alignment checks because they're done only at CPL3. Also, no need to preserve EFLAGS. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1360592538-10643-2-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-31x86/head_32.S: Early update ucode in 32-bitFenghua Yu1-0/+11
This updates ucode in 32-bit kernel on BSP and AP. At this point, there is no paging and no virtual address yet. Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Link: http://lkml.kernel.org/r/1356075872-3054-10-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-01-19x86-32: Start out cr0 clean, disable paging before modifying cr3/4H. Peter Anvin1-2/+7
Patch 5a5a51db78e x86-32: Start out eflags and cr4 clean ... made x86-32 match x86-64 in that we initialize %eflags and %cr4 from scratch. This broke OLPC XO-1.5, because the XO enters the kernel with paging enabled, which the kernel doesn't expect. Since we no longer support 386 (the source of most of the variability in %cr0 configuration), we can simply match further x86-64 and initialize %cr0 to a fixed value -- the one variable part remaining in %cr0 is for FPU control, but all that is handled later on in initialization; in particular, configuring %cr0 as if the FPU is present until proven otherwise is correct and necessary for the probe to work. To deal with the XO case sanely, explicitly disable paging in %cr0 before we muck with %cr3, %cr4 or EFER -- those operations are inherently unsafe with paging enabled. NOTE: There is still a lot of 386-related junk in head_32.S which we can and should get rid of, however, this is intended as a minimal fix whereas the cleanup can be deferred to the next merge window. Reported-by: Andres Salomon <dilinger@queued.net> Tested-by: Daniel Drake <dsd@laptop.org> Link: http://lkml.kernel.org/r/50FA0661.2060400@linux.intel.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>