linux/arch/x86
Dave Hansen 58e65b51e6 x86/pti: Fix boot warning from Global-bit setting
commit 231df823c4f04176f607afc4576c989895cff40e

The pageattr.c code attempts to process "faults" when it goes looking
for PTEs to change and finds non-present entries.  It allows these
faults in the linear map which is "expected to have holes", but
WARN()s about them elsewhere, like when called on the kernel image.

However, change_page_attr_clear() is now called on the kernel image in the
process of trying to clear the Global bit.

This trips the warning in __cpa_process_fault() if a non-present PTE is
encountered in the kernel image.  The "holes" in the kernel image result
from free_init_pages()'s use of set_memory_np().  These holes are totally
fine, and result from normal operation, just as they would be in the kernel
linear map.

Just silence the warning when holes in the kernel image are encountered.

Fixes: 39114b7a7 (x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image)
Reported-by: Mariusz Ceier <mceier@gmail.com>
Reported-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Kees Cook <keescook@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: https://lkml.kernel.org/r/20180420222021.1C7D2B3F@viggo.jf.intel.com
2018-04-25 11:02:50 +02:00
..
boot x86/mm: Do not auto-massage page protections 2018-04-12 09:04:22 +02:00
configs
crypto crypto: x86/des3_ede - des3_ede_skciphers[] can be static 2018-03-09 22:45:53 +08:00
entry Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
events perf/x86/intel/uncore: Fix SBOX support for Broadwell CPUs 2018-04-20 13:17:50 +02:00
hyperv x86/hyper-v: allocate and use Virtual Processor Assist Pages 2018-03-28 22:47:06 +02:00
ia32 syscalls/x86: auto-create compat_sys_*() prototypes 2018-04-02 20:16:18 +02:00
include Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-22 11:40:52 -07:00
kernel Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-22 11:40:52 -07:00
kvm Bug fixes, plus a new test case and the associated infrastructure for 2018-04-16 11:24:28 -07:00
lib Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 15:16:43 -07:00
math-emu
mm x86/pti: Fix boot warning from Global-bit setting 2018-04-25 11:02:50 +02:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
oprofile
pci Merge branch 'x86-dma-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 17:18:45 -07:00
platform Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 17:46:37 -07:00
power x86/power/64: Fix page-table setup for temporary text mapping 2018-04-20 11:52:00 +02:00
purgatory kernel/kexec_file.c: move purgatories sha256 to common code 2018-04-13 17:10:28 -07:00
ras
realmode
tools
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2018-04-11 16:36:47 -07:00
video
xen Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-15 16:12:35 -07:00
.gitignore
Kbuild
Kconfig Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-15 16:12:35 -07:00
Kconfig.cpu Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-03-25 07:36:02 -10:00
Kconfig.debug
Makefile Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 14:37:03 -07:00
Makefile.um
Makefile_32.cpu