Commit Graph

5 Commits

Author SHA1 Message Date
Linus Torvalds b7d5c92398 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Thomas Gleixner:
 "Assorted updates to kexec/kdump:

   - Proper kexec support for 4/5-level paging and jumping from a
     5-level to a 4-level paging kernel.

   - Make the EFI support for kexec/kdump more robust

   - Enforce that the GDT is properly aligned instead of getting the
     alignment by chance"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kdump/64: Restrict kdump kernel reservation to <64TB
  x86/kexec/64: Prevent kexec from 5-level paging to a 4-level only kernel
  x86/boot: Add xloadflags bits to check for 5-level paging support
  x86/boot: Make the GDT 8-byte aligned
  x86/kexec: Add the ACPI NVS region to the ident map
  x86/boot: Call get_rsdp_addr() after console_init()
  Revert "x86/boot: Disable RSDP parsing temporarily"
  x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernels
  x86/kexec: Add the EFI system tables and ACPI tables to the ident map
2019-07-09 11:35:38 -07:00
Baoquan He 8ff80fbe7e x86/kdump/64: Restrict kdump kernel reservation to <64TB
Restrict kdump to only reserve crashkernel below 64TB.

The reaons is that the kdump may jump from a 5-level paging mode to a
4-level paging mode kernel. If a 4-level paging mode kdump kernel is put
above 64TB, then the kdump kernel cannot start.

The 1st kernel reserves the kdump kernel region during bootup. At that
point it is not known whether the kdump kernel has 5-level or 4-level
paging support.

To support both restrict the kdump kernel reservation to the lower 64TB
address space to ensure that a 4-level paging mode kdump kernel can be
loaded and successfully started.

[ tglx: Massaged changelog ]

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20190524073810.24298-4-bhe@redhat.com
2019-06-28 07:14:59 +02:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Ard Biesheuvel f2b9ba871b arm64/kernel: kaslr: reduce module randomization range to 4 GB
We currently have to rely on the GCC large code model for KASLR for
two distinct but related reasons:
- if we enable full randomization, modules will be loaded very far away
  from the core kernel, where they are out of range for ADRP instructions,
- even without full randomization, the fact that the 128 MB module region
  is now no longer fully reserved for kernel modules means that there is
  a very low likelihood that the normal bottom-up allocation of other
  vmalloc regions may collide, and use up the range for other things.

Large model code is suboptimal, given that each symbol reference involves
a literal load that goes through the D-cache, reducing cache utilization.
But more importantly, literals are not instructions but part of .text
nonetheless, and hence mapped with executable permissions.

So let's get rid of our dependency on the large model for KASLR, by:
- reducing the full randomization range to 4 GB, thereby ensuring that
  ADRP references between modules and the kernel are always in range,
- reduce the spillover range to 4 GB as well, so that we fallback to a
  region that is still guaranteed to be in range
- move the randomization window of the core kernel to the middle of the
  VMALLOC space

Note that KASAN always uses the module region outside of the vmalloc space,
so keep the kernel close to that if KASAN is enabled.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-08 13:49:26 +00:00
Alessandro Rubini dccd2304cc ARM: 7430/1: sizes.h: move from asm-generic to <linux/sizes.h>
sizes.h is used throughout the AMBA code and drivers, so the header
should be available to everyone in order to driver AMBA/PrimeCell
peripherals behind a PCI bridge where the host can be any platform
(I'm doing it under x86).

At this step <asm-generic/sizes.h> includes <linux/sizes.h>,
to allow a grace period for both in-tree and out-of-tree drivers.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-06-28 17:14:34 +01:00