65f4d6d0f8
Pull x86 pti fixes from Thomas Gleixner:
"A set of updates for the x86/pti related code:
- Preserve r8-r11 in int $0x80. r8-r11 need to be preserved, but the
int$80 entry code removed that quite some time ago. Make it correct
again.
- A set of fixes for the Global Bit work which went into 4.17 and
caused a bunch of interesting regressions:
- Triggering a BUG in the page attribute code due to a missing
check for early boot stage
- Warnings in the page attribute code about holes in the kernel
text mapping which are caused by the freeing of the init code.
Handle such holes gracefully.
- Reduce the amount of kernel memory which is set global to the
actual text and do not incidentally overlap with data.
- Disable the global bit when RANDSTRUCT is enabled as it
partially defeats the hardening.
- Make the page protection setup correct for vma->page_prot
population again. The adjustment of the protections fell through
the crack during the Global bit rework and triggers warnings on
machines which do not support certain features, e.g. NX"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/64/compat: Preserve r8-r11 in int $0x80
x86/pti: Filter at vma->vm_page_prot population
x86/pti: Disallow global kernel text with RANDSTRUCT
x86/pti: Reduce amount of kernel text allowed to be Global
x86/pti: Fix boot warning from Global-bit setting
x86/pti: Fix boot problems from Global-bit setting
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.