Commit Graph

540 Commits

Author SHA1 Message Date
Linus Torvalds
85fbf15bc9 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes were:

   - Extend the boot protocol to allow future extensions without hitting
     the setup_header size limit.

   - Add quirk to devicetree systems to disable the RTC unless it's
     listed as a supported device.

   - Fix ld.lld linker pedantry"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Introduce setup_indirect
  x86/boot: Introduce kernel_info.setup_type_max
  x86/boot: Introduce kernel_info
  x86/init: Allow DT configured systems to disable RTC at boot time
  x86/realmode: Explicitly set entry point via ENTRY in linker script
2019-11-26 08:40:20 -08:00
Daniel Kiper
b3c72fc9a7 x86/boot: Introduce setup_indirect
The setup_data is a bit awkward to use for extremely large data objects,
both because the setup_data header has to be adjacent to the data object
and because it has a 32-bit length field. However, it is important that
intermediate stages of the boot process have a way to identify which
chunks of memory are occupied by kernel data. Thus introduce an uniform
way to specify such indirect data as setup_indirect struct and
SETUP_INDIRECT type.

And finally bump setup_header version in arch/x86/boot/header.S.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: ard.biesheuvel@linaro.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: dave.hansen@linux.intel.com
Cc: eric.snowberg@oracle.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: kanth.ghatraju@oracle.com
Cc: linux-doc@vger.kernel.org
Cc: linux-efi <linux-efi@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rdunlap@infradead.org
Cc: ross.philipson@oracle.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191112134640.16035-4-daniel.kiper@oracle.com
2019-11-12 16:21:15 +01:00
Daniel Kiper
00cd1c154d x86/boot: Introduce kernel_info.setup_type_max
This field contains maximal allowed type for setup_data.

Do not bump setup_header version in arch/x86/boot/header.S because it
will be followed by additional changes coming into the Linux/x86 boot
protocol.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: ard.biesheuvel@linaro.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: dave.hansen@linux.intel.com
Cc: eric.snowberg@oracle.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: kanth.ghatraju@oracle.com
Cc: linux-doc@vger.kernel.org
Cc: linux-efi <linux-efi@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rdunlap@infradead.org
Cc: ross.philipson@oracle.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191112134640.16035-3-daniel.kiper@oracle.com
2019-11-12 16:16:54 +01:00
Daniel Kiper
2c33c27fd6 x86/boot: Introduce kernel_info
The relationships between the headers are analogous to the various data
sections:

  setup_header = .data
  boot_params/setup_data = .bss

What is missing from the above list? That's right:

  kernel_info = .rodata

We have been (ab)using .data for things that could go into .rodata or .bss for
a long time, for lack of alternatives and -- especially early on -- inertia.
Also, the BIOS stub is responsible for creating boot_params, so it isn't
available to a BIOS-based loader (setup_data is, though).

setup_header is permanently limited to 144 bytes due to the reach of the
2-byte jump field, which doubles as a length field for the structure, combined
with the size of the "hole" in struct boot_params that a protected-mode loader
or the BIOS stub has to copy it into. It is currently 119 bytes long, which
leaves us with 25 very precious bytes. This isn't something that can be fixed
without revising the boot protocol entirely, breaking backwards compatibility.

boot_params proper is limited to 4096 bytes, but can be arbitrarily extended
by adding setup_data entries. It cannot be used to communicate properties of
the kernel image, because it is .bss and has no image-provided content.

kernel_info solves this by providing an extensible place for information about
the kernel image. It is readonly, because the kernel cannot rely on a
bootloader copying its contents anywhere, but that is OK; if it becomes
necessary it can still contain data items that an enabled bootloader would be
expected to copy into a setup_data chunk.

Do not bump setup_header version in arch/x86/boot/header.S because it
will be followed by additional changes coming into the Linux/x86 boot
protocol.

Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: ard.biesheuvel@linaro.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: dave.hansen@linux.intel.com
Cc: eric.snowberg@oracle.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: kanth.ghatraju@oracle.com
Cc: linux-doc@vger.kernel.org
Cc: linux-efi <linux-efi@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rdunlap@infradead.org
Cc: ross.philipson@oracle.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191112134640.16035-2-daniel.kiper@oracle.com
2019-11-12 16:10:34 +01:00
Kairui Song
220dd7699c x86, efi: Never relocate kernel below lowest acceptable address
Currently, kernel fails to boot on some HyperV VMs when using EFI.
And it's a potential issue on all x86 platforms.

It's caused by broken kernel relocation on EFI systems, when below three
conditions are met:

1. Kernel image is not loaded to the default address (LOAD_PHYSICAL_ADDR)
   by the loader.
2. There isn't enough room to contain the kernel, starting from the
   default load address (eg. something else occupied part the region).
3. In the memmap provided by EFI firmware, there is a memory region
   starts below LOAD_PHYSICAL_ADDR, and suitable for containing the
   kernel.

EFI stub will perform a kernel relocation when condition 1 is met. But
due to condition 2, EFI stub can't relocate kernel to the preferred
address, so it fallback to ask EFI firmware to alloc lowest usable memory
region, got the low region mentioned in condition 3, and relocated
kernel there.

It's incorrect to relocate the kernel below LOAD_PHYSICAL_ADDR. This
is the lowest acceptable kernel relocation address.

The first thing goes wrong is in arch/x86/boot/compressed/head_64.S.
Kernel decompression will force use LOAD_PHYSICAL_ADDR as the output
address if kernel is located below it. Then the relocation before
decompression, which move kernel to the end of the decompression buffer,
will overwrite other memory region, as there is no enough memory there.

To fix it, just don't let EFI stub relocate the kernel to any address
lower than lowest acceptable address.

[ ardb: introduce efi_low_alloc_above() to reduce the scope of the change ]

Signed-off-by: Kairui Song <kasong@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20191029173755.27149-6-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-31 09:40:19 +01:00
Zhenzhong Duan
228d120051 x86/boot/acpi: Move get_cmdline_acpi_rsdp() under #ifdef guard
When building with "EXTRA_CFLAGS=-Wall" gcc warns:

arch/x86/boot/compressed/acpi.c:29:30: warning: get_cmdline_acpi_rsdp defined but not used [-Wunused-function]

get_cmdline_acpi_rsdp() is only used when CONFIG_RANDOMIZE_BASE and
CONFIG_MEMORY_HOTREMOVE are both enabled, so any build where one of these
config options is disabled has this issue.

Move the function under the same ifdef guard as the call site.

[ tglx: Add context to the changelog so it becomes useful ]

Fixes: 41fa1ee9c6 ("acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1569719633-32164-1-git-send-email-zhenzhong.duan@oracle.com
2019-10-18 13:33:38 +02:00
Steve Wahl
1869dbe87c x86/boot/64: Round memory hole size up to next PMD page
The kernel image map is created using PMD pages, which can include
some extra space beyond what's actually needed.  Round the size of the
memory hole we search for up to the next PMD boundary, to be certain
all of the space to be mapped is usable RAM and includes no reserved
areas.

Signed-off-by: Steve Wahl <steve.wahl@hpe.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: dimitri.sivanich@hpe.com
Cc: Feng Tang <feng.tang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jordan Borgner <mail@jordan-borgner.de>
Cc: Juergen Gross <jgross@suse.com>
Cc: mike.travis@hpe.com
Cc: russ.anderson@hpe.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Link: https://lkml.kernel.org/r/df4f49f05c0c27f108234eb93db5c613d09ea62e.1569358539.git.steve.wahl@hpe.com
2019-10-11 18:47:23 +02:00
Linus Torvalds
aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Jiri Slaby
98ededb61f x86/asm: Make some functions local labels
Boris suggests to make a local label (prepend ".L") to these functions
to eliminate them from the symbol table. These are functions with very
local names and really should not be visible anywhere.

Note that objtool won't see these functions anymore (to generate ORC
debug info). But all the functions are not annotated with ENDPROC, so
they won't have objtool's attention anyway.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steve Winslow <swinslow@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Huang <wei@redhat.com>
Cc: x86-ml <x86@kernel.org>
Cc: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Link: https://lkml.kernel.org/r/20190906075550.23435-2-jslaby@suse.cz
2019-09-06 10:41:11 +02:00
Kirill A. Shutemov
c96e8483cb x86/boot/compressed/64: Fix missing initialization in find_trampoline_placement()
Gustavo noticed that 'new' can be left uninitialized if 'bios_start'
happens to be less or equal to 'entry->addr + entry->size'.

Initialize the variable at the begin of the iteration to the current value
of 'bios_start'.

Fixes: 0a46fff2f9 ("x86/boot/compressed/64: Fix boot on machines with broken E820 table")
Reported-by: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190826133326.7cxb4vbmiawffv2r@box
2019-08-27 10:46:27 +02:00
Josh Boyer
41fa1ee9c6 acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
This option allows userspace to pass the RSDP address to the kernel, which
makes it possible for a user to modify the workings of hardware. Reject
the option when the kernel is locked down. This requires some reworking
of the existing RSDP command line logic, since the early boot code also
makes use of a command-line passed RSDP when locating the SRAT table
before the lockdown code has been initialised. This is achieved by
separating the command line RSDP path in the early boot code from the
generic RSDP path, and then copying the command line RSDP into boot
params in the kernel proper if lockdown is not enabled. If lockdown is
enabled and an RSDP is provided on the command line, this will only be
used when parsing SRAT (which shouldn't permit kernel code execution)
and will be ignored in the rest of the kernel.

(Modified by Matthew Garrett in order to handle the early boot RSDP
environment)

Signed-off-by: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: Dave Young <dyoung@redhat.com>
cc: linux-acpi@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Kirill A. Shutemov
0a46fff2f9 x86/boot/compressed/64: Fix boot on machines with broken E820 table
BIOS on Samsung 500C Chromebook reports very rudimentary E820 table that
consists of 2 entries:

  BIOS-e820: [mem 0x0000000000000000-0x0000000000000fff] usable
  BIOS-e820: [mem 0x00000000fffff000-0x00000000ffffffff] reserved

It breaks logic in find_trampoline_placement(): bios_start lands on the
end of the first 4k page and trampoline start gets placed below 0.

Detect underflow and don't touch bios_start for such cases. It makes
kernel ignore E820 table on machines that doesn't have two usable pages
below BIOS_START_MAX.

Fixes: 1b3a626436 ("x86/boot/compressed/64: Validate trampoline placement against E820")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=203463
Link: https://lkml.kernel.org/r/20190813131654.24378-1-kirill.shutemov@linux.intel.com
2019-08-19 15:59:13 +02:00
Zhenzhong Duan
8c5477e804 x86, boot: Remove multiple copy of static function sanitize_boot_params()
Kernel build warns:
 'sanitize_boot_params' defined but not used [-Wunused-function]

at below files:
  arch/x86/boot/compressed/cmdline.c
  arch/x86/boot/compressed/error.c
  arch/x86/boot/compressed/early_serial_console.c
  arch/x86/boot/compressed/acpi.c

That's becausethey each include misc.h which includes a definition of
sanitize_boot_params() via bootparam_utils.h.

Remove the inclusion from misc.h and have the c file including
bootparam_utils.h directly.

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1563283092-1189-1-git-send-email-zhenzhong.duan@oracle.com
2019-07-18 21:41:57 +02:00
Zhenzhong Duan
449f328637 x86/boot/compressed/64: Remove unused variable
Fix gcc warning:

arch/x86/boot/compressed/pgtable_64.c: In function 'find_trampoline_placement':
arch/x86/boot/compressed/pgtable_64.c:43:16: warning: unused variable 'trampoline_start' [-Wunused-variable]
  unsigned long trampoline_start;
               ^

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/1563283040-31101-1-git-send-email-zhenzhong.duan@oracle.com
2019-07-18 21:41:57 +02:00
Zhenzhong Duan
cd6697b8b8 x86/boot/efi: Remove unused variables
Fix gcc warnings:

arch/x86/boot/compressed/eboot.c: In function 'make_boot_params':
arch/x86/boot/compressed/eboot.c:394:6: warning: unused variable 'i' [-Wunused-variable]
  int i;
      ^
arch/x86/boot/compressed/eboot.c:393:6: warning: unused variable 's1' [-Wunused-variable]
  u8 *s1;
      ^
arch/x86/boot/compressed/eboot.c:392:7: warning: unused variable 's2' [-Wunused-variable]
  u16 *s2;
       ^
arch/x86/boot/compressed/eboot.c:387:8: warning: unused variable 'options' [-Wunused-variable]
  void *options, *handle;
        ^
arch/x86/boot/compressed/eboot.c: In function 'add_e820ext':
arch/x86/boot/compressed/eboot.c:498:16: warning: unused variable 'size' [-Wunused-variable]
  unsigned long size;
                ^
arch/x86/boot/compressed/eboot.c:497:15: warning: unused variable 'status' [-Wunused-variable]
  efi_status_t status;
               ^
arch/x86/boot/compressed/eboot.c: In function 'exit_boot_func':
arch/x86/boot/compressed/eboot.c:681:15: warning: unused variable 'status' [-Wunused-variable]
  efi_status_t status;
               ^
arch/x86/boot/compressed/eboot.c:680:8: warning: unused variable 'nr_desc' [-Wunused-variable]
  __u32 nr_desc;
        ^
arch/x86/boot/compressed/eboot.c: In function 'efi_main':
arch/x86/boot/compressed/eboot.c:750:22: warning: unused variable 'image' [-Wunused-variable]
  efi_loaded_image_t *image;
                      ^

Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1563282957-26898-1-git-send-email-zhenzhong.duan@oracle.com
2019-07-18 21:41:57 +02:00
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
Xiaoyao Li
2238246ff8 x86/boot: Make the GDT 8-byte aligned
The segment descriptors are loaded with an implicitly LOCK-ed instruction,
which could trigger the split lock #AC exception if the variable is not
properly aligned and crosses a cache line.

Align the GDT properly so the descriptors are all 8 byte aligned.

Signed-off-by: Xiaoyao Li <xiaoyao.li@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Link: https://lkml.kernel.org/r/20190627045525.105266-1-xiaoyao.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-27 10:56:11 +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
Thomas Gleixner
97873a3daf treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497
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>
2019-06-19 17:09:53 +02:00
Borislav Petkov
5b51ae969e x86/boot: Call get_rsdp_addr() after console_init()
... so that early debugging output from the RSDP parsing code can be
visible and collected.

Suggested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: kexec@lists.infradead.org
Cc: x86@kernel.org
2019-06-06 20:29:27 +02:00
Borislav Petkov
8e44c78404 Revert "x86/boot: Disable RSDP parsing temporarily"
TODO:

- ask dyoung and Dirk van der Merwe <dirk.vandermerwe@netronome.com> to
test again.

This reverts commit 36f0c42355.

Now that the required fixes are in place, reenable early RSDP parsing.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
2019-06-06 20:29:06 +02:00
Junichi Nomura
0a23ebc66a x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernels
Commit

  3a63f70bf4 ("x86/boot: Early parse RSDP and save it in boot_params")

broke kexec boot on EFI systems. efi_get_rsdp_addr() in the early
parsing code tries to search RSDP from the EFI tables but that will
crash because the table address is virtual when the kernel was booted by
kexec (set_virtual_address_map() has run in the first kernel and cannot
be run again in the second kernel).

In the case of kexec, the physical address of EFI tables is provided via
efi_setup_data in boot_params, which is set up by kexec(1).

Factor out the table parsing code and use different pointers depending
on whether the kernel is booted by kexec or not.

 [ bp: Massage. ]

Fixes: 3a63f70bf4 ("x86/boot: Early parse RSDP and save it in boot_params")
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Dave Young <dyoung@redhat.com>
Link: https://lkml.kernel.org/r/20190408231011.GA5402@jeru.linux.bs1.fc.nec.co.jp
2019-06-06 20:28:37 +02:00
Thomas Gleixner
04672fe6d6 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 268
Based on 1 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
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 51 franklin street fifth floor boston ma
  02110 1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 46 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141334.135501091@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:30:29 +02:00
Ard Biesheuvel
c3ee82ce47 x86/boot: Provide KASAN compatible aliases for string routines
The KASAN subsystem wraps calls to memcpy(), memset() and memmove()
to sanitize the arguments before invoking the actual routines, which
have been renamed to __memcpy(), __memset() and __memmove(),
respectively. When CONFIG_KASAN is enabled for the kernel build but
KASAN code generation is disabled for the compilation unit (which is
needed for things like the EFI stub or the decompressor), the string
routines are just #define'd to their __ prefixed names so that they
are simply invoked directly.

This does however rely on those __ prefixed names to exist in the
symbol namespace, which is not currently the case for the x86
decompressor, which may lead to errors like

  drivers/firmware/efi/libstub/tpm.o: In function `efi_retrieve_tpm2_eventlog':
  tpm.c:(.text+0x2a8): undefined reference to `__memcpy'

So let's expose the __ prefixed symbols in the decompressor when
KASAN is enabled.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <matthewgarrett@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-05-24 08:44:16 +02:00
Rafael J. Wysocki
317e2cac45 Merge branch 'acpica'
* acpica:
  ACPICA: Update version to 20190405
  ACPICA: Namespace: add check to avoid null pointer dereference
  ACPICA: Update version to 20190329
  ACPICA: utilities: fix spelling of PCC to platform_comm_channel
  ACPICA: Rename nameseg length macro/define for clarity
  ACPICA: Rename nameseg compare macro for clarity
  ACPICA: Rename nameseg copy macro for clarity
2019-05-06 10:49:01 +02:00
Borislav Petkov
36f0c42355 x86/boot: Disable RSDP parsing temporarily
The original intention to move RDSP parsing very early, before KASLR
does its ranges selection, was to accommodate movable memory regions
machines (CONFIG_MEMORY_HOTREMOVE) to still be able to do memory
hotplug.

However, that broke kexec'ing a kernel on EFI machines because depending
on where the EFI systab was mapped, on at least one machine it isn't
present in the kexec mapping of the second kernel, leading to a triple
fault in the early code.

Fixing this properly requires significantly involved surgery and we
cannot allow ourselves to do that, that close to the merge window.

So disable the RSDP parsing code temporarily until it is fixed properly
in the next release cycle.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190419141952.GE10324@zn.tnic
2019-04-22 11:36:43 +02:00
Bob Moore
5599fb6935 ACPICA: Rename nameseg compare macro for clarity
ACPICA commit 92ec0935f27e217dff0b176fca02c2ec3d782bb5

ACPI_COMPARE_NAME changed to ACPI_COMPARE_NAMESEG
This clarifies (1) this is a compare on 4-byte namesegs, not
a generic compare. Improves understanding of the code.

Link: https://github.com/acpica/acpica/commit/92ec0935
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-09 10:08:28 +02:00
Baoquan He
0f02daed4e x86/boot: Fix incorrect ifdeffery scope
The declarations related to immovable memory handling are out of the
BOOT_COMPRESSED_MISC_H #ifdef scope, wrap them inside.

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190304055546.18566-1-bhe@redhat.com
2019-03-27 14:00:51 +01:00
Linus Torvalds
b6e3cb4e86 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot fix from Thomas Gleixner:
 "A trivial fix for the previous x86/boot pull request which did not
  make it in time"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/KASLR: Always return a value from process_mem_region
2019-03-10 14:44:35 -07:00
Linus Torvalds
bcd49c3dd1 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Various cleanups and simplifications, none of them really stands out,
  they are all over the place"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/uaccess: Remove unused __addr_ok() macro
  x86/smpboot: Remove unused phys_id variable
  x86/mm/dump_pagetables: Remove the unused prev_pud variable
  x86/fpu: Move init_xstate_size() to __init section
  x86/cpu_entry_area: Move percpu_setup_debug_store() to __init section
  x86/mtrr: Remove unused variable
  x86/boot/compressed/64: Explain paging_prepare()'s return value
  x86/resctrl: Remove duplicate MSR_MISC_FEATURE_CONTROL definition
  x86/asm/suspend: Drop ENTRY from local data
  x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery
  x86/boot: Save several bytes in decompressor
  x86/trap: Remove useless declaration
  x86/mm/tlb: Remove unused cpu variable
  x86/events: Mark expected switch-case fall-throughs
  x86/asm-prototypes: Remove duplicate include <asm/page.h>
  x86/kernel: Mark expected switch-case fall-throughs
  x86/insn-eval: Mark expected switch-case fall-through
  x86/platform/UV: Replace kmalloc() and memset() with k[cz]alloc() calls
  x86/e820: Replace kmalloc() + memcpy() with kmemdup()
2019-03-07 16:36:57 -08:00
Linus Torvalds
f14b5f05cd Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 build updates from Ingo Molnar:
 "Misc cleanups and a retpoline code generation optimization"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, retpolines: Raise limit for generating indirect calls from switch-case
  x86/build: Use the single-argument OUTPUT_FORMAT() linker script command
  x86/build: Specify elf_i386 linker emulation explicitly for i386 objects
  x86/build: Mark per-CPU symbols as absolute explicitly for LLD
2019-03-07 13:38:27 -08:00
Linus Torvalds
37d18565e4 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Most of the changes center around the difficult problem of KASLR
  pinning down hot-removable memory regions. At the very early stage
  KASRL is making irreversible kernel address layout decisions we don't
  have full knowledge about the memory maps yet.

  So the changes from Chao Fan add this (parsing the RSDP table early),
  together with fixes from Borislav Petkov"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/compressed/64: Do not read legacy ROM on EFI system
  x86/boot: Correct RSDP parsing with 32-bit EFI
  x86/kexec: Fill in acpi_rsdp_addr from the first kernel
  x86/boot: Fix randconfig build error due to MEMORY_HOTREMOVE
  x86/boot: Fix cmdline_find_option() prototype visibility
  x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only
  x86/boot: Parse SRAT table and count immovable memory regions
  x86/boot: Early parse RSDP and save it in boot_params
  x86/boot: Search for RSDP in memory
  x86/boot: Search for RSDP in the EFI tables
  x86/boot: Add "acpi_rsdp=" early parsing
  x86/boot: Copy kstrtoull() to boot/string.c
  x86/boot: Build the command line parsing code unconditionally
2019-03-07 13:35:41 -08:00
Louis Taylor
e4a0bd0308 x86/boot/KASLR: Always return a value from process_mem_region
When compiling with -Wreturn-type, clang warns:

arch/x86/boot/compressed/kaslr.c:704:1: warning: control may reach end of
      non-void function [-Wreturn-type]

This function's return statement should have been placed outside the
ifdeffed region. Move it there.

Fixes: 690eaa5320 ("x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only")
Signed-off-by: Louis Taylor <louis@kragniz.eu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: bhe@redhat.com
Cc: kirill.shutemov@linux.intel.com
Cc: jflat@chromium.org
Link: https://lkml.kernel.org/r/20190302184929.28971-1-louis@kragniz.eu
2019-03-06 22:55:30 +01:00
Kirill A. Shutemov
6f913de323 x86/boot/compressed/64: Do not read legacy ROM on EFI system
EFI systems do not necessarily provide a legacy ROM. If the ROM is missing
the memory is not mapped at all.

Trying to dereference values in the legacy ROM area leads to a crash on
Macbook Pro.

Only look for values in the legacy ROM area for non-EFI system.

Fixes: 3548e131ec ("x86/boot/compressed/64: Find a place for 32-bit trampoline")
Reported-by: Pitam Mitra <pitamm@gmail.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Bockjoo Kim <bockjoo@phys.ufl.edu>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190219075224.35058-1-kirill.shutemov@linux.intel.com
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202351
2019-02-28 12:25:05 +01:00
Borislav Petkov
f9d230e893 x86/boot: Correct RSDP parsing with 32-bit EFI
Guenter Roeck reported triple faults of a 64-bit VM using a 32-bit OVMF
EFI image. After some singlestepping of the image in gdb, it turned out
that some of the EFI config tables were at bogus addresses. Which, as
Ard pointed out, results from using the wrong efi_config_table typedef.

So switch all EFI table pointers to unsigned longs and convert them to
the proper typedef only when accessing them. This way, the proper table
type is being used.

Shorten variable names, while at it.

Fixes: 33f0df8d84 ("x86/boot: Search for RSDP in the EFI tables")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190208190248.GA10854@roeck-us.net
2019-02-13 12:19:05 +01:00
Kirill A. Shutemov
82434d23f3 x86/boot/compressed/64: Explain paging_prepare()'s return value
paging_prepare() returns a two-quadword structure which lands
into RDX:RAX:

  - Address of the trampoline is returned in RAX.
  - Non zero RDX means trampoline needs to enable 5-level paging.

Document that explicitly.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: dave.hansen@linux.intel.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Kyle D Pelton <kyle.d.pelton@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Huang <wei@redhat.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190206154756.matwldebbxkmlnae@black.fi.intel.com
2019-02-06 19:08:34 +01:00
Kirill A. Shutemov
45b13b424f x86/boot/compressed/64: Do not corrupt EDX on EFER.LME=1 setting
RDMSR in the trampoline code overwrites EDX but that register is used
to indicate whether 5-level paging has to be enabled and if clobbered,
leads to failure to boot on a 5-level paging machine.

Preserve EDX on the stack while we are dealing with EFER.

Fixes: b677dfae5a ("x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning to long mode")
Reported-by: Kyle D Pelton <kyle.d.pelton@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: dave.hansen@linux.intel.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Huang <wei@redhat.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190206115253.1907-1-kirill.shutemov@linux.intel.com
2019-02-06 18:56:18 +01:00
Borislav Petkov
82df8261c6 x86/boot: Fix randconfig build error due to MEMORY_HOTREMOVE
When building randconfigs, one of the failures is:

  ld: arch/x86/boot/compressed/kaslr.o: in function `choose_random_location':
  kaslr.c:(.text+0xbf7): undefined reference to `count_immovable_mem_regions'
  ld: kaslr.c:(.text+0xcbe): undefined reference to `immovable_mem'
  make[2]: *** [arch/x86/boot/compressed/vmlinux] Error 1

because CONFIG_ACPI is not enabled in this particular .config but
CONFIG_MEMORY_HOTREMOVE is and count_immovable_mem_regions() is
unresolvable because it is defined in compressed/acpi.c which is the
compilation unit that depends on CONFIG_ACPI.

Add CONFIG_ACPI to the explicit dependencies for MEMORY_HOTREMOVE.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190205131033.9564-1-bp@alien8.de
2019-02-06 11:48:42 +01:00
Borislav Petkov
82f9ed3a93 x86/boot: Fix cmdline_find_option() prototype visibility
ac09c5f43c ("x86/boot: Build the command line parsing code unconditionally")

enabled building the command line parsing code unconditionally but it
forgot to remove the respective ifdeffery around the prototypes in the
misc.h header, leading to

  arch/x86/boot/compressed/acpi.c: In function ‘get_acpi_rsdp’:
  arch/x86/boot/compressed/acpi.c:37:8: warning: implicit declaration of function \
	  ‘cmdline_find_option’ [-Wimplicit-function-declaration]
    ret = cmdline_find_option("acpi_rsdp", val, MAX_ADDR_LEN);
          ^~~~~~~~~~~~~~~~~~~

for configs where neither CONFIG_EARLY_PRINTK nor CONFIG_RANDOMIZE_BASE
was defined.

Drop the ifdeffery in the header too.

Fixes: ac09c5f43c ("x86/boot: Build the command line parsing code unconditionally")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/5c51daf0.83pQEkvDZILqoSYW%lkp@intel.com
Link: https://lkml.kernel.org/r/20190205131352.GA27396@zn.tnic
2019-02-06 11:41:21 +01:00
Chao Fan
690eaa5320 x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only
KASLR may randomly choose a range which is located in movable memory
regions. As a result, this will break memory hotplug and make the
movable memory chosen by KASLR immovable.

Therefore, limit KASLR to choose memory regions in the immovable range
after consulting the SRAT table.

 [ bp:
    - Rewrite commit message.
    - Trim comments.
 ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: caoj.fnst@cn.fujitsu.com
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-8-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:55 +01:00
Chao Fan
02a3e3cdb7 x86/boot: Parse SRAT table and count immovable memory regions
Parse SRAT for the immovable memory regions and use that information to
control which offset KASLR selects so that it doesn't overlap with any
movable region.

 [ bp:
   - Move struct mem_vector where it is visible so that it builds.
   - Correct comments.
   - Rewrite commit message.
   ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: <caoj.fnst@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <indou.takao@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: <kasong@redhat.com>
Cc: <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <msys.mizuma@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-7-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:55 +01:00
Chao Fan
3a63f70bf4 x86/boot: Early parse RSDP and save it in boot_params
The RSDP is needed by KASLR so parse it early and save it in
boot_params.acpi_rsdp_addr, before KASLR setup runs.

RSDP is needed by other kernel facilities so have the parsing code
built-in instead of a long "depends on" line in Kconfig.

 [ bp:
    - Trim commit message and comments
    - Add CONFIG_ACPI dependency in the Makefile
    - Move ->acpi_rsdp_addr assignment with the rest of boot_params massaging in extract_kernel().
 ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-6-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:55 +01:00
Chao Fan
93a209aaaa x86/boot: Search for RSDP in memory
Scan memory (EBDA) for the RSDP and verify RSDP by signature and
checksum.

 [ bp:
   - Trim commit message.
   - Simplify bios_get_rsdp_addr() and cleanup mad casting.
 ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-5-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:55 +01:00
Chao Fan
33f0df8d84 x86/boot: Search for RSDP in the EFI tables
The immovable memory ranges information in the SRAT table is necessary
to fix the issue of KASLR not paying attention to movable memory regions
when selecting the offset. Therefore, SRAT needs to be parsed.

Depending on the boot: KEXEC/EFI/BIOS, the methods to compute RSDP are
different. When booting from EFI, the EFI table points to the RSDP. So
iterate over the EFI system tables in order to find the RSDP.

 [ bp:
   - Heavily massage commit message
   - Trim comments
   - Move the CONFIG_ACPI ifdeffery into the Makefile.
 ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-4-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:54 +01:00
Chao Fan
3c98e71b42 x86/boot: Add "acpi_rsdp=" early parsing
KASLR may randomly choose offsets which are located in movable memory
regions resulting in the movable memory becoming immovable.

The ACPI SRAT (System/Static Resource Affinity Table) describes memory
ranges including ranges of memory provided by hot-added memory devices.
In order to access SRAT, one needs the Root System Description Pointer
(RSDP) with which to find the Root/Extended System Description Table
(R/XSDT) which then contains the system description tables of which SRAT
is one of.

In case the RSDP address has been passed on the command line (kexec-ing
a second kernel) parse it from there.

 [ bp: Rewrite the commit message and cleanup the code. ]

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: caoj.fnst@cn.fujitsu.com
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-3-fanc.fnst@cn.fujitsu.com
2019-02-01 11:52:54 +01:00
Borislav Petkov
ac09c5f43c x86/boot: Build the command line parsing code unconditionally
Just drop the three-item ifdeffery and build it in unconditionally.
Early cmdline parsing is needed more often than not.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: bhe@redhat.com
Cc: hpa@zytor.com
Cc: indou.takao@jp.fujitsu.com
Cc: kasong@redhat.com
Cc: keescook@chromium.org
Cc: mingo@redhat.com
Cc: msys.mizuma@gmail.com
Cc: tglx@linutronix.de
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190130112238.GB18383@zn.tnic
2019-02-01 11:51:01 +01:00
Cao jin
0a278662f5 x86/boot: Save several bytes in decompressor
gdt64 represents the content of GDTR under x86-64, which actually needs
10 bytes only, ".long" & ".word" is superfluous.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <bp@alien8.de>
Cc: <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20190123100014.23721-1-caoj.fnst@cn.fujitsu.com
2019-01-29 22:09:12 +01:00
Wei Huang
b677dfae5a x86/boot/compressed/64: Set EFER.LME=1 in 32-bit trampoline before returning to long mode
In some old AMD KVM implementation, guest's EFER.LME bit is cleared by KVM
when the hypervsior detects that the guest sets CR0.PG to 0. This causes
the guest OS to reboot when it tries to return from 32-bit trampoline code
because the CPU is in incorrect state: CR4.PAE=1, CR0.PG=1, CS.L=1, but
EFER.LME=0.  As a precaution, set EFER.LME=1 as part of long mode
activation procedure. This extra step won't cause any harm when Linux is
booted on a bare-metal machine.

Signed-off-by: Wei Huang <wei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Link: https://lkml.kernel.org/r/20190104054411.12489-1-wei@redhat.com
2019-01-29 21:58:59 +01:00
Borislav Petkov
e6d7bc0bdf x86/build: Use the single-argument OUTPUT_FORMAT() linker script command
The various x86 linker scripts use the three-argument linker script
command variant OUTPUT_FORMAT(DEFAULT, BIG, LITTLE) which specifies
three object file formats when the -EL and -EB linker command line
options are used. When -EB is specified, OUTPUT_FORMAT issues the BIG
object file format, when -EL, LITTLE, respectively, and when neither is
specified, DEFAULT.

However, those -E[LB] options are not used by arch/x86/ so switch to the
simple OUTPUT_FORMAT(BFDNAME) macro variant.

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190109181531.27513-1-bp@alien8.de
2019-01-16 12:21:53 +01:00
Masahiro Yamada
172caf1993 kbuild: remove redundant target cleaning on failure
Since commit 9c2af1c737 ("kbuild: add .DELETE_ON_ERROR special
target"), the target file is automatically deleted on failure.

The boilerplate code

  ... || { rm -f $@; false; }

is unneeded.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-06 09:46:51 +09:00