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2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497Thomas Gleixner
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>
2016-12-19Revert "x86/boot: Fail the boot if !M486 and CPUID is missing"Andy Lutomirski
This reverts commit ed68d7e9b9cfb64f3045ffbcb108df03c09a0f98. The patch wasn't quite correct -- there are non-Intel (and hence non-486) CPUs that we support that don't have CPUID. Since we no longer require CPUID for sync_core(), just revert the patch. I think the relevant CPUs are Geode and Elan, but I'm not sure. In principle, we should try to do better at identifying CPUID-less CPUs in early boot, but that's more complicated. Reported-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Juergen Gross <jgross@suse.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Matthew Whitehead <tedheadster@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: xen-devel <Xen-devel@lists.xen.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/82acde18a108b8e353180dd6febcc2876df33f24.1481307769.git.luto@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-21x86/boot: Fail the boot if !M486 and CPUID is missingAndy Lutomirski
Linux will have all kinds of sporadic problems on systems that don't have the CPUID instruction unless CONFIG_M486=y. In particular, sync_core() will explode. I believe that these kernels had a better chance of working before commit 05fb3c199bb0 ("x86/boot: Initialize FPU and X86_FEATURE_ALWAYS even if we don't have CPUID"). That commit inadvertently fixed a serious bug: we used to fail to detect the FPU if CPUID wasn't present. Because we also used to forget to set X86_FEATURE_ALWAYS, we end up with no cpu feature bits set at all. This meant that alternative patching didn't do anything and, if paravirt was disabled, we could plausibly finish the entire boot process without calling sync_core(). Rather than trying to work around these issues, just have the kernel fail loudly if it's running on a CPUID-less 486, doesn't have CPUID, and doesn't have CONFIG_M486 set. Reported-by: Matthew Whitehead <tedheadster@gmail.com> Signed-off-by: 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/70eac6639f23df8be5fe03fa1984aedd5d40077a.1479598603.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-13x86/mm: Disallow running with 32-bit PTEs to work around erratumDave Hansen
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>
2014-08-17x86: Support compiling out human-friendly processor feature namesJosh Triplett
The table mapping CPUID bits to human-readable strings takes up a non-trivial amount of space, and only exists to support /proc/cpuinfo and a couple of kernel messages. Since programs depend on the format of /proc/cpuinfo, force inclusion of the table when building with /proc support; otherwise, support omitting that table to save space, in which case the kernel messages will print features numerically instead. In addition to saving 1408 bytes out of vmlinux, this also saves 1373 bytes out of the uncompressed setup code, which contributes directly to the size of bzImage. Signed-off-by: Josh Triplett <josh@joshtriplett.org>
2008-09-16x86 setup: handle more than 8 CPU flag wordsH. Peter Anvin
Checkin e38e05a85828dac23540cd007df5f20985388afc added a 9th CPU flag word, but didn't adjust the boot code to match. This patch adds the necessary boot code support. Note: due to a typo in an #if statement, it didn't trigger the #error this was supposed to do. Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-08-14x86: cleanup for setup code crashes during IST probeH. Peter Anvin
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>
2008-05-28x86: Fix up silly i1586 boot message.Dave Jones
Trying to boot a 64-bit kernel on a 32bit Pentium 4 gets you an amusing message along the lines of. "you need an x86-64, but you only have an i1586" due to the P4 being family F. Munge it to be 686. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-02-04x86 setup: print missing CPU features in cleartextH. Peter Anvin
Instead of obscure numbers, print the list of missing CPU features in cleartext. To conserve space, use a host program (mkcpustr.c) to produce a compact list of mandatory features only. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-11i386: move bootThomas Gleixner
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>