Commit Graph

412 Commits

Author SHA1 Message Date
Vivek Goyal
3d379225c4 x86, boot: Do not include boot.h in string.c
string.c does not require whole of boot.h. Just inclusion of linux/types.h
and ctypes.h seems to be sufficient.

Keep list of stuff being included in string.c to bare minimal so that
string.c can be included in other places easily.

For example, Currently boot/compressed/string.c includes boot/string.c
but looks like it does not want boot/boot.h. Hence there is a define
in boot/compressed/misc.h "define BOOT_BOOT_H" which prevents inclusion
of boot.h in compressed/string.c. And compressed/string.c is forced to
include misc.h just for that reason.

So by removing inclusion of boot.h, we can also get rid of inclusion of
misch.h in compressed/misc.c.

This also enables including of boot/string.c in purgatory/ code relatively
easily.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1398447972-27896-2-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-05-08 08:00:01 -07:00
Linus Torvalds
8eab6cd031 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Peter Anvin:
 "This is a collection of minor fixes for x86, plus the IRET information
  leak fix (forbid the use of 16-bit segments in 64-bit mode)"

NOTE! We may have to relax the "forbid the use of 16-bit segments in
64-bit mode" part, since there may be people who still run and depend on
16-bit Windows binaries under Wine.

But I'm taking this in the current unconditional form for now to see who
(if anybody) screams bloody murder.  Maybe nobody cares.  And maybe
we'll have to update it with some kind of runtime enablement (like our
vm.mmap_min_addr tunable that people who run dosemu/qemu/wine already
need to tweak).

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64, modify_ldt: Ban 16-bit segments on 64-bit kernels
  efi: Pass correct file handle to efi_file_{read,close}
  x86/efi: Correct EFI boot stub use of code32_start
  x86/efi: Fix boot failure with EFI stub
  x86/platform/hyperv: Handle VMBUS driver being a module
  x86/apic: Reinstate error IRQ Pentium erratum 3AP workaround
  x86, CMCI: Add proper detection of end of CMCI storms
2014-04-11 11:58:33 -07:00
Ingo Molnar
3151b942ba * Fix EFI boot regression introduced during the merge window where the
firmware was reading random values from the stack because we were
    passing a pointer to the wrong object type.
 
  * Kernel corruption has been reported when booting with the EFI boot
    stub which was tracked down to setting a bogus value for
    bp->hdr.code32_start, resulting in corruption during relocation.
 
  * Olivier Martin reported that the wrong file handles were being passed
    to efi_file_(read|close), which works for x86 by luck due to the way
    that the FAT driver is implemented, but doesn't work on ARM.
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Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

"* Fix EFI boot regression introduced during the merge window where the
   firmware was reading random values from the stack because we were
   passing a pointer to the wrong object type.

 * Kernel corruption has been reported when booting with the EFI boot
   stub which was tracked down to setting a bogus value for
   bp->hdr.code32_start, resulting in corruption during relocation.

 * Olivier Martin reported that the wrong file handles were being passed
   to efi_file_(read|close), which works for x86 by luck due to the way
   that the FAT driver is implemented, but doesn't work on ARM."

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-11 10:25:28 +02:00
Matt Fleming
47514c996f efi: Pass correct file handle to efi_file_{read,close}
We're currently passing the file handle for the root file system to
efi_file_read() and efi_file_close(), instead of the file handle for the
file we wish to read/close.

While this has worked up until now, it seems that it has only been by
pure luck. Olivier explains,

 "The issue is the UEFI Fat driver might return the same function for
  'fh->read()' and 'h->read()'. While in our case it does not work with
  a different implementation of EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. In our
  case, we return a different pointer when reading a directory and
  reading a file."

Fixing this actually clears up the two functions because we can drop one
of the arguments, and instead only pass a file 'handle' argument.

Reported-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-10 21:20:03 +01:00
Matt Fleming
7e8213c1f3 x86/efi: Correct EFI boot stub use of code32_start
code32_start should point at the start of the protected mode code, and
*not* at the beginning of the bzImage. This is much easier to do in
assembly so document that callers of make_boot_params() need to fill out
code32_start.

The fallout from this bug is that we would end up relocating the image
but copying the image at some offset, resulting in what appeared to be
memory corruption.

Reported-by: Thomas Bächler <thomas@archlinux.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-10 21:19:52 +01:00
Matt Fleming
396f1a08db x86/efi: Fix boot failure with EFI stub
commit 54b52d8726 ("x86/efi: Build our own EFI services pointer
table") introduced a regression because the 64-bit file_size()
implementation passed a pointer to a 32-bit data object, instead of a
pointer to a 64-bit object.

Because the firmware treats the object as 64-bits regardless it was
reading random values from the stack for the upper 32-bits.

This resulted in people being unable to boot their machines, after
seeing the following error messages,

    Failed to get file info size
    Failed to alloc highmem for files

Reported-by: Dzmitry Sledneu <dzmitry.sledneu@gmail.com>
Reported-by: Koen Kooi <koen@dominion.thruhere.net>
Tested-by: Koen Kooi <koen@dominion.thruhere.net>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-04-10 21:19:47 +01:00
Linus Torvalds
9447dc4394 Merge branch 'x86/boot' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot changes from Peter Anvin:
 "This patchset is a set of cleanups aiming at librarize some of the
  common code from the boot environments.  We currently have three
  different "little environments" (boot, boot/compressed, and
  realmode/rm) in x86, and we are likely to soon get a fourth one
  (kexec/purgatory, which will have to be integrated in the kernel to
  support secure kexec).  This is primarily a cleanup in the
  anticipation of the latter.

  While Vivek implemented this, he ran into some bugs, in particular the
  memcmp implementation for when gcc punts from using the builtin would
  have a misnamed symbol, causing compilation errors if we were ever
  unlucky enough that gcc didn't want to inline the test"

* 'x86/boot' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, boot: Move memset() definition in compressed/string.c
  x86, boot: Move memcmp() into string.h and string.c
  x86, boot: Move optimized memcpy() 32/64 bit versions to compressed/string.c
  x86, boot: Create a separate string.h file to provide standard string functions
  x86, boot: Undef memcmp before providing a new definition
2014-04-02 12:23:49 -07:00
Linus Torvalds
7cc3afdf43 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI changes from Ingo Molnar:
 "The main changes:

  - Add debug code to the dump EFI pagetable - Borislav Petkov

  - Make 1:1 runtime mapping robust when booting on machines with lots
    of memory - Borislav Petkov

  - Move the EFI facilities bits out of 'x86_efi_facility' and into
    efi.flags which is the standard architecture independent place to
    keep EFI state, by Matt Fleming.

  - Add 'EFI mixed mode' support: this allows 64-bit kernels to be
    booted from 32-bit firmware.  This needs a bootloader that supports
    the 'EFI handover protocol'.  By Matt Fleming"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  x86, efi: Abstract x86 efi_early calls
  x86/efi: Restore 'attr' argument to query_variable_info()
  x86/efi: Rip out phys_efi_get_time()
  x86/efi: Preserve segment registers in mixed mode
  x86/boot: Fix non-EFI build
  x86, tools: Fix up compiler warnings
  x86/efi: Re-disable interrupts after calling firmware services
  x86/boot: Don't overwrite cr4 when enabling PAE
  x86/efi: Wire up CONFIG_EFI_MIXED
  x86/efi: Add mixed runtime services support
  x86/efi: Firmware agnostic handover entry points
  x86/efi: Split the boot stub into 32/64 code paths
  x86/efi: Add early thunk code to go from 64-bit to 32-bit
  x86/efi: Build our own EFI services pointer table
  efi: Add separate 32-bit/64-bit definitions
  x86/efi: Delete dead code when checking for non-native
  x86/mm/pageattr: Always dump the right page table in an oops
  x86, tools: Consolidate #ifdef code
  x86/boot: Cleanup header.S by removing some #ifdefs
  efi: Use NULL instead of 0 for pointer
  ...
2014-03-31 12:26:05 -07:00
Linus Torvalds
918d80a136 Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu handling changes from Ingo Molnar:
 "Bigger changes:

   - Intel CPU hardware-enablement: new vector instructions support
     (AVX-512), by Fenghua Yu.

   - Support the clflushopt instruction and use it in appropriate
     places.  clflushopt is similar to clflush but with more relaxed
     ordering, by Ross Zwisler.

   - MSR accessor cleanups, by Borislav Petkov.

   - 'forcepae' boot flag for those who have way too much time to spend
     on way too old Pentium-M systems and want to live way too
     dangerously, by Chris Bainbridge"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M
  Rename TAINT_UNSAFE_SMP to TAINT_CPU_OUT_OF_SPEC
  x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic
  x86, Intel: Convert to the new bit access MSR accessors
  x86, AMD: Convert to the new bit access MSR accessors
  x86: Add another set of MSR accessor functions
  x86: Use clflushopt in drm_clflush_virt_range
  x86: Use clflushopt in drm_clflush_page
  x86: Use clflushopt in clflush_cache_range
  x86: Add support for the clflushopt instruction
  x86, AVX-512: Enable AVX-512 States Context Switch
  x86, AVX-512: AVX-512 Feature Detection
2014-03-31 12:00:45 -07:00
Matt Fleming
204b0a1a4b x86, efi: Abstract x86 efi_early calls
The ARM EFI boot stub doesn't need to care about the efi_early
infrastructure that x86 requires in order to do mixed mode thunking. So
wrap everything up in an efi_call_early() macro.

This allows x86 to do the necessary indirection jumps to call whatever
firmware interface is necessary (native or mixed mode), but also allows
the ARM folks to mask the fact that they don't support relocation in the
boot stub and need to pass 'sys_table_arg' to every function.

[ hpa: there are no object code changes from this patch ]

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/20140326091011.GB2958@console-pimps.org
Cc: Roy Franz <roy.franz@linaro.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-26 11:30:03 -07:00
Chris Bainbridge
69f2366c94 x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.

Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-03-20 16:31:54 -07:00
Vivek Goyal
04999550f9 x86, boot: Move memset() definition in compressed/string.c
Currently compressed/misc.c needs to link against memset(). I think one of
the reasons of this need is inclusion of various header files which define
static inline functions and use memset() inside these. For example,
include/linux/bitmap.h

I think trying to include "../string.h" and using builtin version of memset
does not work because by the time "#define memset" shows up, it is too
late. Some other header file has already used memset() and expects to
find a definition during link phase.

Currently we have a C definitoin of memset() in misc.c. Move it to
compressed/string.c so that others can use it if need be.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-6-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-19 15:44:09 -07:00
Vivek Goyal
fb4cac573e x86, boot: Move memcmp() into string.h and string.c
Try to treat memcmp() in same way as memcpy() and memset(). Provide a
declaration in boot/string.h and by default user gets a memcmp() which
maps to builtin function.

Move optimized definition of memcmp() in boot/string.c. Now a user can
do #undef memcmp and link against string.c to use optimzied memcmp().

It also simplifies boot/compressed/string.c where we had to redefine
memcmp(). That extra definition is gone now.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-5-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-19 15:44:04 -07:00
Vivek Goyal
820e8feca0 x86, boot: Move optimized memcpy() 32/64 bit versions to compressed/string.c
Move optimized versions of memcpy to compressed/string.c This will allow
any other code to use these functions too if need be in future. Again
trying to put definition in a common place instead of hiding it in misc.c

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-4-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-19 15:43:59 -07:00
Vivek Goyal
c041b5ad86 x86, boot: Create a separate string.h file to provide standard string functions
Create a separate arch/x86/boot/string.h file to provide declaration of
some of the common string functions.

By default memcpy, memset and memcmp functions will default to gcc
builtin functions. If code wants to use an optimized version of any
of these functions, they need to #undef the respective macro and link
against a local file providing definition of undefed function.

For example, arch/x86/boot/* code links against copy.S to get memcpy()
and memcmp() definitions. arch/86/boot/compressed/* links against
compressed/string.c.

There are quite a few places in arch/x86/ where these functions are
used. Idea is to try to consilidate  their declaration and possibly
definitions so that it can be reused.

I am planning to reuse boot/string.h in arch/x86/purgatory/ and use
gcc builtin functions for memcpy, memset and memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-3-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-19 15:43:45 -07:00
Vivek Goyal
aad830938e x86, boot: Undef memcmp before providing a new definition
With CONFIG_X86_32=y, string_32.h gets pulled in compressed/string.c by
"misch.h". string_32.h defines a macro to map memcmp to __builtin_memcmp().
And that macro in turn changes the name of memcmp() defined here and
converts it to __builtin_memcmp().

I thought that's not the intention though. We probably want to provide
our own optimized definition of memcmp(). If yes, then undef the memcmp
before we define a new memcmp.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1395170800-11059-2-git-send-email-vgoyal@redhat.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-19 15:43:37 -07:00
Borislav Petkov
3e920b532a x86, boot: Correct max ramdisk size name
The name in struct bootparam is ->initrd_addr_max and not ramdisk_max.
Fix that.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1394633584-5509-2-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-03-13 15:32:42 -07:00
Matt Fleming
617b3c37da Merge branch 'mixed-mode' into efi-for-mingo 2014-03-05 18:18:50 +00:00
Matt Fleming
994448f1af Merge remote-tracking branch 'tip/x86/efi-mixed' into efi-for-mingo
Conflicts:
	arch/x86/kernel/setup.c
	arch/x86/platform/efi/efi.c
	arch/x86/platform/efi/efi_64.c
2014-03-05 18:15:37 +00:00
Matt Fleming
3db4cafdfd x86/boot: Fix non-EFI build
The kbuild test robot reported the following errors, introduced with
commit 54b52d8726 ("x86/efi: Build our own EFI services pointer
table"),

 arch/x86/boot/compressed/head_32.o: In function `efi32_config':
>> (.data+0x58): undefined reference to `efi_call_phys'

 arch/x86/boot/compressed/head_64.o: In function `efi64_config':
>> (.data+0x90): undefined reference to `efi_call6'

Wrap the efi*_config structures in #ifdef CONFIG_EFI_STUB so that we
don't make references to EFI functions if they're not compiled in.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-05 10:19:07 +00:00
Matt Fleming
b663a68583 x86, tools: Fix up compiler warnings
The kbuild test robot reported the following errors that were introduced
with commit 993c30a04e ("x86, tools: Consolidate #ifdef code"),

  arch/x86/boot/tools/build.c: In function 'update_pecoff_setup_and_reloc':
>> arch/x86/boot/tools/build.c:252:1: error: parameter name omitted
    static inline void update_pecoff_setup_and_reloc(unsigned int) {}
    ^
  arch/x86/boot/tools/build.c: In function 'update_pecoff_text':
>> arch/x86/boot/tools/build.c:253:1: error: parameter name omitted
    static inline void update_pecoff_text(unsigned int, unsigned int) {}
    ^
>> arch/x86/boot/tools/build.c:253:1: error: parameter name omitted

   arch/x86/boot/tools/build.c: In function 'main':
>> arch/x86/boot/tools/build.c:372:2: warning: implicit declaration of function 'efi_stub_entry_update' [-Wimplicit-function-declaration]
    efi_stub_entry_update();
    ^
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-05 10:12:39 +00:00
Matt Fleming
108d3f44b1 x86/boot: Don't overwrite cr4 when enabling PAE
Some EFI firmware makes use of the FPU during boottime services and
clearing X86_CR4_OSFXSR by overwriting %cr4 causes the firmware to
crash.

Add the PAE bit explicitly instead of trashing the existing contents,
leaving the rest of the bits as the firmware set them.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:43:59 +00:00
Matt Fleming
7d453eee36 x86/efi: Wire up CONFIG_EFI_MIXED
Add the Kconfig option and bump the kernel header version so that boot
loaders can check whether the handover code is available if they want.

The xloadflags field in the bzImage header is also updated to reflect
that the kernel supports both entry points by setting both of
XLF_EFI_HANDOVER_32 and XLF_EFI_HANDOVER_64 when CONFIG_EFI_MIXED=y.
XLF_CAN_BE_LOADED_ABOVE_4G is disabled so that the kernel text is
guaranteed to be addressable with 32-bits.

Note that no boot loaders should be using the bits set in xloadflags to
decide which entry point to jump to. The entire scheme is based on the
concept that 32-bit bootloaders always jump to ->handover_offset and
64-bit loaders always jump to ->handover_offset + 512. We set both bits
merely to inform the boot loader that it's safe to use the native
handover offset even if the machine type in the PE/COFF header claims
otherwise.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:43:57 +00:00
Matt Fleming
b8ff87a615 x86/efi: Firmware agnostic handover entry points
The EFI handover code only works if the "bitness" of the firmware and
the kernel match, i.e. 64-bit firmware and 64-bit kernel - it is not
possible to mix the two. This goes against the tradition that a 32-bit
kernel can be loaded on a 64-bit BIOS platform without having to do
anything special in the boot loader. Linux distributions, for one thing,
regularly run only 32-bit kernels on their live media.

Despite having only one 'handover_offset' field in the kernel header,
EFI boot loaders use two separate entry points to enter the kernel based
on the architecture the boot loader was compiled for,

    (1) 32-bit loader: handover_offset
    (2) 64-bit loader: handover_offset + 512

Since we already have two entry points, we can leverage them to infer
the bitness of the firmware we're running on, without requiring any boot
loader modifications, by making (1) and (2) valid entry points for both
CONFIG_X86_32 and CONFIG_X86_64 kernels.

To be clear, a 32-bit boot loader will always use (1) and a 64-bit boot
loader will always use (2). It's just that, if a single kernel image
supports (1) and (2) that image can be used with both 32-bit and 64-bit
boot loaders, and hence both 32-bit and 64-bit EFI.

(1) and (2) must be 512 bytes apart at all times, but that is already
part of the boot ABI and we could never change that delta without
breaking existing boot loaders anyhow.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:25:06 +00:00
Matt Fleming
c116e8d60a x86/efi: Split the boot stub into 32/64 code paths
Make the decision which code path to take at runtime based on
efi_early->is64.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:25:05 +00:00
Matt Fleming
0154416a71 x86/efi: Add early thunk code to go from 64-bit to 32-bit
Implement the transition code to go from IA32e mode to protected mode in
the EFI boot stub. This is required to use 32-bit EFI services from a
64-bit kernel.

Since EFI boot stub is executed in an identity-mapped region, there's
not much we need to do before invoking the 32-bit EFI boot services.
However, we do reload the firmware's global descriptor table
(efi32_boot_gdt) in case things like timer events are still running in
the firmware.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:25:04 +00:00
Matt Fleming
54b52d8726 x86/efi: Build our own EFI services pointer table
It's not possible to dereference the EFI System table directly when
booting a 64-bit kernel on a 32-bit EFI firmware because the size of
pointers don't match.

In preparation for supporting the above use case, build a list of
function pointers on boot so that callers don't have to worry about
converting pointer sizes through multiple levels of indirection.

Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:25:03 +00:00
Matt Fleming
677703cef0 efi: Add separate 32-bit/64-bit definitions
The traditional approach of using machine-specific types such as
'unsigned long' does not allow the kernel to interact with firmware
running in a different CPU mode, e.g. 64-bit kernel with 32-bit EFI.

Add distinct EFI structure definitions for both 32-bit and 64-bit so
that we can use them in the 32-bit and 64-bit code paths.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:25:02 +00:00
Matt Fleming
993c30a04e x86, tools: Consolidate #ifdef code
Instead of littering main() with #ifdef CONFIG_EFI_STUB, move the logic
into separate functions that do nothing if the config option isn't set.
This makes main() much easier to read.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:23:35 +00:00
Matt Fleming
86134a1b39 x86/boot: Cleanup header.S by removing some #ifdefs
handover_offset is now filled out by build.c. Don't set a default value
as it will be overwritten anyway.

Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-03-04 21:23:34 +00:00
Kees Cook
e290e8c59d x86, kaslr: add missed "static" declarations
This silences build warnings about unexported variables and functions.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20140209215644.GA30339@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-02-25 16:59:29 -08:00
David Woodhouse
5fbbc25a99 x86, boot: Fix word-size assumptions in has_eflag() inline asm
Commit dd78b97367 ("x86, boot: Move CPU
flags out of cpucheck") introduced ambiguous inline asm in the
has_eflag() function. In 16-bit mode want the instruction to be
'pushfl', but we just say 'pushf' and hope the compiler does what we
wanted.

When building with 'clang -m16', it won't, because clang doesn't use
the horrid '.code16gcc' hack that even 'gcc -m16' uses internally.

Say what we mean and don't make the compiler make assumptions.

[ hpa: ideally we would be able to use the gcc %zN construct here, but
  that is broken for 64-bit integers in gcc < 4.5.

  The code with plain "pushf/popf" is fine for 32- or 64-bit mode, but
  not for 16-bit mode; in 16-bit mode those are 16-bit instructions in
  .code16 mode, and 32-bit instructions in .code16gcc mode. ]

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1391079628.26079.82.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-30 08:04:32 -08:00
H. Peter Anvin
4064e0ea3c Merge commit 'f4bcd8ccddb02833340652e9f46f5127828eb79d' into x86/build
Bring in upstream merge of x86/kaslr for future patches.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-29 09:07:00 -08:00
David Woodhouse
9b3965f740 x86, boot: Use __attribute__((used)) to ensure videocard structs are emitted
It looks like GCC will always emit an object that is marked with an
explicit section, although the documentation doesn't say that and we
possibly shouldn't be relying on it.

Clang does *not* do so, so add __attribute__((used)) to make sure.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1389180083-23249-2-git-send-email-David.Woodhouse@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-22 04:21:45 -08:00
David Woodhouse
1c678da3bd x86: Remove duplication of 16-bit CFLAGS
Define them once in arch/x86/Makefile instead of twice.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1389180083-23249-1-git-send-email-David.Woodhouse@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-22 04:21:45 -08:00
Linus Torvalds
f4bcd8ccdd Merge branch 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 kernel address space randomization support from Peter Anvin:
 "This enables kernel address space randomization for x86"

* 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, kaslr: Clarify RANDOMIZE_BASE_MAX_OFFSET
  x86, kaslr: Remove unused including <linux/version.h>
  x86, kaslr: Use char array to gain sizeof sanity
  x86, kaslr: Add a circular multiply for better bit diffusion
  x86, kaslr: Mix entropy sources together as needed
  x86/relocs: Add percpu fixup for GNU ld 2.23
  x86, boot: Rename get_flags() and check_flags() to *_cpuflags()
  x86, kaslr: Raise the maximum virtual address to -1 GiB on x86_64
  x86, kaslr: Report kernel offset on panic
  x86, kaslr: Select random position from e820 maps
  x86, kaslr: Provide randomness functions
  x86, kaslr: Return location from decompress_kernel
  x86, boot: Move CPU flags out of cpucheck
  x86, relocs: Add more per-cpu gold special cases
2014-01-20 14:45:50 -08:00
Linus Torvalds
972d5e7e5b Merge branch 'x86-efi-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI changes from Ingo Molnar:
 "This consists of two main parts:

   - New static EFI runtime services virtual mapping layout which is
     groundwork for kexec support on EFI (Borislav Petkov)

   - EFI kexec support itself (Dave Young)"

* 'x86-efi-kexec-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/efi: parse_efi_setup() build fix
  x86: ksysfs.c build fix
  x86/efi: Delete superfluous global variables
  x86: Reserve setup_data ranges late after parsing memmap cmdline
  x86: Export x86 boot_params to sysfs
  x86: Add xloadflags bit for EFI runtime support on kexec
  x86/efi: Pass necessary EFI data for kexec via setup_data
  efi: Export EFI runtime memory mapping to sysfs
  efi: Export more EFI table variables to sysfs
  x86/efi: Cleanup efi_enter_virtual_mode() function
  x86/efi: Fix off-by-one bug in EFI Boot Services reservation
  x86/efi: Add a wrapper function efi_map_region_fixed()
  x86/efi: Remove unused variables in __map_region()
  x86/efi: Check krealloc return value
  x86/efi: Runtime services virtual mapping
  x86/mm/cpa: Map in an arbitrary pgd
  x86/mm/pageattr: Add last levels of error path
  x86/mm/pageattr: Add a PUD error unwinding path
  x86/mm/pageattr: Add a PTE pagetable populating function
  x86/mm/pageattr: Add a PMD pagetable populating function
  ...
2014-01-20 12:05:30 -08:00
Wei Yongjun
19259943f0 x86, kaslr: Remove unused including <linux/version.h>
Remove including <linux/version.h> that don't need it.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Link: http://lkml.kernel.org/r/CAPgLHd-Fjx1RybjWFAu1vHRfTvhWwMLL3x46BouC5uNxHPjy1A@mail.gmail.com
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-14 10:45:56 -08:00
Ingo Molnar
ef0b8b9a52 Linux 3.13-rc7
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Merge tag 'v3.13-rc7' into x86/efi-kexec to resolve conflicts

Conflicts:
	arch/x86/platform/efi/efi.c
	drivers/firmware/efi/Kconfig

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-01-05 12:34:29 +01:00
H. Peter Anvin
6f34152f54 x86, boot: Move intcall() to the .inittext section
The .inittext section tries to aggregate all functions which are
needed to get a message out in the case of a load failure.  However,
putchar() uses intcall(), so intcall() should be in the .inittext
section.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-twxm8igouzbmsklmf6lfyq0w@git.kernel.org
2014-01-04 14:29:08 -08:00
David Woodhouse
e24df921af x86, boot: Use .code16 instead of .code16gcc
This reverts commit 28b48688 ("x86, boot: use .code16gcc instead
of .code16").

Versions of binutils older than 2.16 are already not working, so this
workaround is no longer necessary either.  At the same time, some of
the transformations that .code16gcc does can be *extremely*
counterintuitive to a human programmer.

[ hpa: folded ret -> retl and call -> calll fixes from followup patch ]

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Link: http://lkml.kernel.org/r/1388788242.2391.75.camel@shinybook.infradead.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2014-01-04 13:59:06 -08:00
Dave Young
456a29ddad x86: Add xloadflags bit for EFI runtime support on kexec
Old kexec-tools can not load new kernels. The reason is kexec-tools does
not fill efi_info in x86 setup header previously, thus EFI failed to
initialize.  In new kexec-tools it will by default to fill efi_info and
pass other EFI required infomation to 2nd kernel so kexec kernel EFI
initialization can succeed finally.

To prevent from breaking userspace, add a new xloadflags bit so
kexec-tools can check the flag and switch to old logic.

Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Borislav Petkov <bp@suse.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-12-29 13:09:06 +00:00
H. Peter Anvin
8b3b005d67 x86, build: Pass in additional -mno-mmx, -mno-sse options
In checkin

    5551a34e5a x86-64, build: Always pass in -mno-sse

we unconditionally added -mno-sse to the main build, to keep newer
compilers from generating SSE instructions from autovectorization.
However, this did not extend to the special environments
(arch/x86/boot, arch/x86/boot/compressed, and arch/x86/realmode/rm).
Add -mno-sse to the compiler command line for these environments, and
add -mno-mmx to all the environments as well, as we don't want a
compiler to generate MMX code either.

This patch also removes a $(cc-option) call for -m32, since we have
long since stopped supporting compilers too old for the -m32 option,
and in fact hardcode it in other places in the Makefiles.

Reported-by: Kevin B. Smith <kevin.b.smith@intel.com>
Cc: Sunil K. Pandey <sunil.k.pandey@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/n/tip-j21wzqv790q834n7yc6g80j1@git.kernel.org
Cc: <stable@vger.kernel.org> # build fix only
2013-12-09 15:52:39 -08:00
Kees Cook
327f7d7245 x86, kaslr: Use char array to gain sizeof sanity
The build_str needs to be char [] not char * for the sizeof() to report
the string length.

Reported-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20131112165607.GA5921@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-11-12 08:58:35 -08:00
H. Peter Anvin
e8236c4d93 x86, kaslr: Add a circular multiply for better bit diffusion
If we don't have RDRAND (in which case nothing else *should* matter),
most sources have a highly biased entropy distribution.  Use a
circular multiply to diffuse the entropic bits.  A circular multiply
is a good operation for this: it is cheap on standard hardware and
because it is symmetric (unlike an ordinary multiply) it doesn't
introduce its own bias.

Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20131111222839.GA28616@www.outflux.net
2013-11-11 23:05:49 -08:00
Kees Cook
a653f3563c x86, kaslr: Mix entropy sources together as needed
Depending on availability, mix the RDRAND and RDTSC entropy together with
XOR. Only when neither is available should the i8254 be used. Update
the Kconfig documentation to reflect this. Additionally, since bits
used for entropy is masked elsewhere, drop the needless masking in
the get_random_long(). Similarly, use the entire TSC, not just the low
32 bits.

Finally, to improve the starting entropy, do a simple hashing of a
build-time versions string and the boot-time boot_params structure for
some additional level of unpredictability.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20131111222839.GA28616@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2013-11-11 22:29:44 -08:00
Linus Torvalds
69019d77c7 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 EFI changes from Ingo Molnar:
 "Main changes:

   - Add support for earlyprintk=efi which uses the EFI framebuffer.
     Very useful for debugging boot problems.

   - EFI stub support for large memory maps (more than 128 entries)

   - EFI ARM support - this was mostly done by generalizing x86 <-> ARM
     platform differences, such as by moving x86 EFI code into
     drivers/firmware/efi/ and sharing it with ARM.

   - Documentation updates

   - misc fixes"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  x86/efi: Add EFI framebuffer earlyprintk support
  boot, efi: Remove redundant memset()
  x86/efi: Fix config_table_type array termination
  x86 efi: bugfix interrupt disabling sequence
  x86: EFI stub support for large memory maps
  efi: resolve warnings found on ARM compile
  efi: Fix types in EFI calls to match EFI function definitions.
  efi: Renames in handle_cmdline_files() to complete generalization.
  efi: Generalize handle_ramdisks() and rename to handle_cmdline_files().
  efi: Allow efi_free() to be called with size of 0
  efi: use efi_get_memory_map() to get final map for x86
  efi: generalize efi_get_memory_map()
  efi: Rename __get_map() to efi_get_memory_map()
  efi: Move unicode to ASCII conversion to shared function.
  efi: Generalize relocate_kernel() for use by other architectures.
  efi: Move relocate_kernel() to shared file.
  efi: Enforce minimum alignment of 1 page on allocations.
  efi: Rename memory allocation/free functions
  efi: Add system table pointer argument to shared functions.
  efi: Move common EFI stub code from x86 arch code to common location
  ...
2013-11-12 10:48:30 +09:00
Linus Torvalds
d96d8aa261 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Two small cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, msr: Use file_inode(), not f_mapping->host
  x86: mkpiggy.c: Explicitly close the output file
2013-11-12 10:45:01 +09:00
H. Peter Anvin
6e6a4932b0 x86, boot: Rename get_flags() and check_flags() to *_cpuflags()
When a function is used in more than one file it may not be possible
to immediately tell from context what the intended meaning is.  As
such, it is more important that the naming be self-evident.  Thus,
change get_flags() to get_cpuflags().

For consistency, change check_flags() to check_cpuflags() even though
it is only used in cpucheck.c.

Link: http://lkml.kernel.org/r/1381450698-28710-2-git-send-email-keescook@chromium.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-10-13 04:08:56 -07:00
Kees Cook
82fa9637a2 x86, kaslr: Select random position from e820 maps
Counts available alignment positions across all e820 maps, and chooses
one randomly for the new kernel base address, making sure not to collide
with unsafe memory areas.

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1381450698-28710-5-git-send-email-keescook@chromium.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-10-13 03:12:19 -07:00