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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 <[email protected]> Reviewed-by: Enrico Weigelt <[email protected]> Reviewed-by: Allison Randal <[email protected]> Reviewed-by: Kate Stewart <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>
2016-12-19Revert "x86/boot: Fail the boot if !M486 and CPUID is missing"Andy Lutomirski1-6/+0
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 <[email protected]> Signed-off-by: Andy Lutomirski <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Matthew Whitehead <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Henrique de Moraes Holschuh <[email protected]> Cc: Andrew Cooper <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: xen-devel <[email protected]> Cc: Linus Torvalds <[email protected]> Link: http://lkml.kernel.org/r/82acde18a108b8e353180dd6febcc2876df33f24.1481307769.git.luto@kernel.org Signed-off-by: Thomas Gleixner <[email protected]>
2016-11-21x86/boot: Fail the boot if !M486 and CPUID is missingAndy Lutomirski1-0/+6
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 <[email protected]> Signed-off-by: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Link: http://lkml.kernel.org/r/70eac6639f23df8be5fe03fa1984aedd5d40077a.1479598603.git.luto@kernel.org Signed-off-by: Ingo Molnar <[email protected]>
2016-07-13x86/mm: Disallow running with 32-bit PTEs to work around erratumDave Hansen1-0/+2
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 <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Luis R. Rodriguez <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Toshi Kani <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]>
2014-08-17x86: Support compiling out human-friendly processor feature namesJosh Triplett1-27/+41
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 <[email protected]>
2008-09-16x86 setup: handle more than 8 CPU flag wordsH. Peter Anvin1-8/+9
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 <[email protected]>
2008-08-14x86: cleanup for setup code crashes during IST probeH. Peter Anvin1-3/+0
Clean up the code for crashes during SpeedStep probing on older machines. Signed-off-by: H. Peter Anvin <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>
2008-05-28x86: Fix up silly i1586 boot message.Dave Jones1-0/+2
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 <[email protected]> Signed-off-by: H. Peter Anvin <[email protected]>
2008-02-04x86 setup: print missing CPU features in cleartextH. Peter Anvin1-5/+21
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 <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]>
2007-10-11i386: move bootThomas Gleixner1-0/+69
Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>