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2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497Thomas Gleixner1-3/+1
Based on 1 normalized pattern(s): this file is part of the linux kernel and is made available under the terms of the gnu general public license version 2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 28 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.534229504@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-29x86: Clean up 'sizeof x' => 'sizeof(x)'Jordan Borgner1-1/+1
"sizeof(x)" is the canonical coding style used in arch/x86 most of the time. Fix the few places that didn't follow the convention. (Also do some whitespace cleanups in a few places while at it.) [ mingo: Rewrote the changelog. ] Signed-off-by: Jordan Borgner <mail@jordan-borgner.de> 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> Link: http://lkml.kernel.org/r/20181028125828.7rgammkgzep2wpam@JordanDesktop Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-04x86/boot: Detect 5-level paging supportKirill A. Shutemov1-0/+9
In this initial implementation we force-require 5-level paging support from the hardware, when compiled with CONFIG_X86_5LEVEL=y. (The kernel will panic during boot on CPUs that don't support 5-level paging.) We will implement boot-time switch between 4- and 5-level paging later. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> 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: Dave Hansen <dave.hansen@intel.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: linux-arch@vger.kernel.org Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20170330080731.65421-2-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-13x86/mm: Disallow running with 32-bit PTEs to work around erratumDave Hansen1-0/+33
The Intel(R) Xeon Phi(TM) Processor x200 Family (codename: Knights Landing) has an erratum where a processor thread setting the Accessed or Dirty bits may not do so atomically against its checks for the Present bit. This may cause a thread (which is about to page fault) to set A and/or D, even though the Present bit had already been atomically cleared. These bits are truly "stray". In the case of the Dirty bit, the thread associated with the stray set was *not* allowed to write to the page. This means that we do not have to launder the bit(s); we can simply ignore them. If the PTE is used for storing a swap index or a NUMA migration index, the A bit could be misinterpreted as part of the swap type. The stray bits being set cause a software-cleared PTE to be interpreted as a swap entry. In some cases (like when the swap index ends up being for a non-existent swapfile), the kernel detects the stray value and WARN()s about it, but there is no guarantee that the kernel can always detect it. When we have 64-bit PTEs (64-bit mode or 32-bit PAE), we were able to move the swap PTE format around to avoid these troublesome bits. But, 32-bit non-PAE is tight on bits. So, disallow it from running on this hardware. I can't imagine anyone wanting to run 32-bit non-highmem kernels on this hardware, but disallowing them from running entirely is surely the safe thing to do. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> 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: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: dave.hansen@intel.com Cc: linux-mm@kvack.org Cc: mhocko@suse.com Link: http://lkml.kernel.org/r/20160708001914.D0B50110@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-02Merge branch 'x86/boot' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds1-0/+1
Pull x86 boot changes from Peter Anvin: "This patchset is a set of cleanups aiming at librarize some of the common code from the boot environments. We currently have three different "little environments" (boot, boot/compressed, and realmode/rm) in x86, and we are likely to soon get a fourth one (kexec/purgatory, which will have to be integrated in the kernel to support secure kexec). This is primarily a cleanup in the anticipation of the latter. While Vivek implemented this, he ran into some bugs, in particular the memcmp implementation for when gcc punts from using the builtin would have a misnamed symbol, causing compilation errors if we were ever unlucky enough that gcc didn't want to inline the test" * 'x86/boot' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, boot: Move memset() definition in compressed/string.c x86, boot: Move memcmp() into string.h and string.c x86, boot: Move optimized memcpy() 32/64 bit versions to compressed/string.c x86, boot: Create a separate string.h file to provide standard string functions x86, boot: Undef memcmp before providing a new definition
2014-03-20x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled ↵Chris Bainbridge1-0/+20
Pentium M Many Pentium M systems disable PAE but may have a functionally usable PAE implementation. This adds the "forcepae" parameter which bypasses the boot check for PAE, and sets the CPU as being PAE capable. Using this parameter will taint the kernel with TAINT_CPU_OUT_OF_SPEC. Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-03-19x86, boot: Create a separate string.h file to provide standard string functionsVivek Goyal1-0/+1
Create a separate arch/x86/boot/string.h file to provide declaration of some of the common string functions. By default memcpy, memset and memcmp functions will default to gcc builtin functions. If code wants to use an optimized version of any of these functions, they need to #undef the respective macro and link against a local file providing definition of undefed function. For example, arch/x86/boot/* code links against copy.S to get memcpy() and memcmp() definitions. arch/86/boot/compressed/* links against compressed/string.c. There are quite a few places in arch/x86/ where these functions are used. Idea is to try to consilidate their declaration and possibly definitions so that it can be reused. I am planning to reuse boot/string.h in arch/x86/purgatory/ and use gcc builtin functions for memcpy, memset and memcmp. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Link: http://lkml.kernel.org/r/1395170800-11059-3-git-send-email-vgoyal@redhat.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-10-13x86, boot: Rename get_flags() and check_flags() to *_cpuflags()H. Peter Anvin1-7/+7
When a function is used in more than one file it may not be possible to immediately tell from context what the intended meaning is. As such, it is more important that the naming be self-evident. Thus, change get_flags() to get_cpuflags(). For consistency, change check_flags() to check_cpuflags() even though it is only used in cpucheck.c. Link: http://lkml.kernel.org/r/1381450698-28710-2-git-send-email-keescook@chromium.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-10-13x86, boot: Move CPU flags out of cpucheckKees Cook1-86/+0
Refactor the CPU flags handling out of the cpucheck routines so that they can be reused by the future ASLR routines (in order to detect CPU features like RDRAND and RDTSC). This reworks has_eflag() and has_fpu() to be used on both 32-bit and 64-bit, and refactors the calls to cpuid to make them PIC-safe on 32-bit. Signed-off-by: Kees Cook <keescook@chromium.org> Link: http://lkml.kernel.org/r/1381450698-28710-2-git-send-email-keescook@chromium.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2008-09-05x86: boot: stub out unimplemented CPU feature wordsH. Peter Anvin1-4/+4
The CPU feature detection code in the boot code is somewhat minimal, and doesn't include all possible CPUID words. In particular, it doesn't contain the code for CPU feature words 2 (Transmeta), 3 (Linux-specific), 5 (VIA), or 7 (scattered). Zero them out, so we can still set those bits as known at compile time; in particular, this allows creating a Linux-specific NOPL flag and have it required (and therefore resolvable at compile time) in 64-bit mode. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-08-14x86: cleanup for setup code crashes during IST probeH. Peter Anvin1-2/+0
Clean up the code for crashes during SpeedStep probing on older machines. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-08-13x86: fix setup code crashes on my old 486 boxJoerg Roedel1-7/+1
yesterday I tried to reactivate my old 486 box and wanted to install a current Linux with latest kernel on it. But it turned out that the latest kernel does not boot because the machine crashes early in the setup code. After some debugging it turned out that the problem is the query_ist() function. If this interrupt with that function is called the machine simply locks up. It looks like a BIOS bug. Looking for a workaround for this problem I wrote the attached patch. It checks for the CPUID instruction and if it is not implemented it does not call the speedstep BIOS function. As far as I know speedstep should be available since some Pentium earliest. Alan Cox observed that it's available since the Pentium II, so cpuid levels 4 and 5 can be excluded altogether. H. Peter Anvin cleaned up the code some more: > Right in concept, but I dislike the implementation (duplication of the > CPU detect code we already have). Could you try this patch and see if > it works for you? which, with a small modification to fix a build error with it the resulting kernel boots on my machine. Signed-off-by: Joerg Roedel <joro@8bytes.org> Signed-off-by: "H. Peter Anvin" <hpa@zytor.com> Cc: <stable@kernel.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-04-19x86: remove pointless commentsWANG Cong1-2/+0
Remove old comments that include the old arch/i386 directory. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2008-04-17x86: coding style fixes to arch/x86/boot/cpucheck.cPaolo Ciarrocchi1-10/+10
Before: total: 30 errors, 0 warnings, 262 lines checked After: total: 0 errors, 0 warnings, 262 lines checked No code changed: arch/x86/boot/cpucheck.o: text data bss dec hex filename 989 0 96 1085 43d cpucheck.o.before 989 0 96 1085 43d cpucheck.o.after md5: 06634cfefb8438fa284ff903b4cafbce cpucheck.o.before.asm 06634cfefb8438fa284ff903b4cafbce cpucheck.o.after.asm Signed-off-by: Paolo Ciarrocchi <paolo.ciarrocchi@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-11-12x86: arch/x86/Kconfig.cpu unificationSam Ravnborg1-6/+0
Move all CPU definitions to Kconfig.cpu Always define X86_MINIMUM_CPU_FAMILY and do the obvious code cleanup in boot/cpucheck.c Comments from: Adrian Bunk <bunk@kernel.org> incorporated. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Adrian Bunk <bunk@kernel.org> Cc: Brian Gerst <bgerst@didntduck.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
2007-10-11i386: move bootThomas Gleixner1-0/+268
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>