linux-toradex.git/arch/x86/kernel/machine_kexec_64.c, branch v4.2.7

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching

2015-06-23T21:07:26+00:00

Pull livepatching fixes from Jiri Kosina:

 - symbol lookup locking fix, from Miroslav Benes

 - error handling improvements in case of failure of the module coming
   notifier, from Minfei Huang

 - we were too pessimistic when kASLR has been enabled on x86 and were
   dropping address hints on the floor unnecessarily in such case.  Fix
   from Jiri Kosina

 - a few other small fixes and cleanups

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: add module locking around kallsyms calls
  livepatch: annotate klp_init() with __init
  livepatch: introduce patch/func-walking helpers
  livepatch: make kobject in klp_object statically allocated
  livepatch: Prevent patch inconsistencies if the coming module notifier fails
  livepatch: match return value to function signature
  x86: kaslr: fix build due to missing ALIGN definition
  livepatch: x86: make kASLR logic more accurate
  x86: introduce kaslr_offset()

x86/mm: Decouple from

2015-06-03T10:02:00+00:00

Nothing in  uses anything from , so
remove it from there and fix up the resulting build problems
triggered on x86 {64|32}-bit {def|allmod|allno}configs.

The breakages were triggering in places where x86 builds relied
on vmalloc() facilities but did not include 
explicitly and relied on the implicit inclusion via .

Also add:

  -  to 
  -  to 

... which were two other implicit header file dependencies.

Suggested-by: David Miller 
Signed-off-by: Stephen Rothwell 
[ Tidied up the changelog. ]
Acked-by: David Miller 
Acked-by: Takashi Iwai 
Acked-by: Viresh Kumar 
Acked-by: Vinod Koul 
Cc: Andrew Morton 
Cc: Anton Vorontsov 
Cc: Boris Ostrovsky 
Cc: Colin Cross 
Cc: David Vrabel 
Cc: H. Peter Anvin 
Cc: Haiyang Zhang 
Cc: James E.J. Bottomley 
Cc: Jaroslav Kysela 
Cc: K. Y. Srinivasan 
Cc: Kees Cook 
Cc: Konrad Rzeszutek Wilk 
Cc: Kristen Carlson Accardi 
Cc: Len Brown 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Rafael J. Wysocki 
Cc: Suma Ramars 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Signed-off-by: Ingo Molnar

x86: introduce kaslr_offset()

2015-04-29T14:51:33+00:00

Offset that has been chosen for kaslr during kernel decompression can be
easily computed as a difference between _text and __START_KERNEL. We are
already making use of this in dump_kernel_offset() notifier and in
arch_crash_save_vmcoreinfo().

Introduce kaslr_offset() that makes this computation instead of hard-coding
it, so that other kernel code (such as live patching) can make use of it.
Also convert existing users to make use of it.

This patch is equivalent transofrmation without any effects on the resulting
code:

	$ diff -u vmlinux.old.asm vmlinux.new.asm
	--- vmlinux.old.asm     2015-04-28 17:55:19.520983368 +0200
	+++ vmlinux.new.asm     2015-04-28 17:55:24.141206072 +0200
	@@ -1,5 +1,5 @@

	-vmlinux.old:     file format elf64-x86-64
	+vmlinux.new:     file format elf64-x86-64

	Disassembly of section .text:
	$

Acked-by: Borislav Petkov 
Signed-off-by: Jiri Kosina

x86, irq: Move IOAPIC related declarations from hw_irq.h into io_apic.h

2014-12-16T13:08:17+00:00

Clean up code by moving IOAPIC related declarations from hw_irq.h into
io_apic.h.

Signed-off-by: Jiang Liu 
Cc: Konrad Rzeszutek Wilk 
Cc: Tony Luck 
Cc: Joerg Roedel 
Cc: Greg Kroah-Hartman 
Cc: H. Peter Anvin 
Cc: Benjamin Herrenschmidt 
Cc: Rafael J. Wysocki 
Cc: Bjorn Helgaas 
Cc: Randy Dunlap 
Cc: Yinghai Lu 
Cc: Borislav Petkov 
Cc: Prarit Bhargava 
Cc: Grant Likely 
Cc: Vivek Goyal 
Cc: Baoquan He 
Cc: Matt Fleming 
Cc: Fenghua Yu 
Cc: Christian Gmeiner 
Cc: Aubrey 
Cc: Ryan Desfosses 
Cc: Quentin Lambert 
Cc: Rafael J. Wysocki 
Link: http://lkml.kernel.org/r/1414397531-28254-14-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner

kexec: create a new config option CONFIG_KEXEC_FILE for new syscall

2014-08-29T23:28:16+00:00

Currently new system call kexec_file_load() and all the associated code
compiles if CONFIG_KEXEC=y.  But new syscall also compiles purgatory
code which currently uses gcc option -mcmodel=large.  This option seems
to be available only gcc 4.4 onwards.

Hiding new functionality behind a new config option will not break
existing users of old gcc.  Those who wish to enable new functionality
will require new gcc.  Having said that, I am trying to figure out how
can I move away from using -mcmodel=large but that can take a while.

I think there are other advantages of introducing this new config
option.  As this option will be enabled only on x86_64, other arches
don't have to compile generic kexec code which will never be used.  This
new code selects CRYPTO=y and CRYPTO_SHA256=y.  And all other arches had
to do this for CONFIG_KEXEC.  Now with introduction of new config
option, we can remove crypto dependency from other arches.

Now CONFIG_KEXEC_FILE is available only on x86_64.  So whereever I had
CONFIG_X86_64 defined, I got rid of that.

For CONFIG_KEXEC_FILE, instead of doing select CRYPTO=y, I changed it to
"depends on CRYPTO=y".  This should be safer as "select" is not
recursive.

Signed-off-by: Vivek Goyal 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Tested-by: Shaun Ruffell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: verify the signature of signed PE bzImage

2014-08-08T22:57:33+00:00

This is the final piece of the puzzle of verifying kernel image signature
during kexec_file_load() syscall.

This patch calls into PE file routines to verify signature of bzImage.  If
signature are valid, kexec_file_load() succeeds otherwise it fails.

Two new config options have been introduced.  First one is
CONFIG_KEXEC_VERIFY_SIG.  This option enforces that kernel has to be
validly signed otherwise kernel load will fail.  If this option is not
set, no signature verification will be done.  Only exception will be when
secureboot is enabled.  In that case signature verification should be
automatically enforced when secureboot is enabled.  But that will happen
when secureboot patches are merged.

Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG.  This option
enables signature verification support on bzImage.  If this option is not
set and previous one is set, kernel image loading will fail because kernel
does not have support to verify signature of bzImage.

I tested these patches with both "pesign" and "sbsign" signed bzImages.

I used signing_key.priv key and signing_key.x509 cert for signing as
generated during kernel build process (if module signing is enabled).

Used following method to sign bzImage.

pesign
======
- Convert DER format cert to PEM format cert
openssl x509 -in signing_key.x509 -inform DER -out signing_key.x509.PEM -outform
PEM

- Generate a .p12 file from existing cert and private key file
openssl pkcs12 -export -out kernel-key.p12 -inkey signing_key.priv -in
signing_key.x509.PEM

- Import .p12 file into pesign db
pk12util -i /tmp/kernel-key.p12 -d /etc/pki/pesign

- Sign bzImage
pesign -i /boot/vmlinuz-3.16.0-rc3+ -o /boot/vmlinuz-3.16.0-rc3+.signed.pesign
-c "Glacier signing key - Magrathea" -s

sbsign
======
sbsign --key signing_key.priv --cert signing_key.x509.PEM --output
/boot/vmlinuz-3.16.0-rc3+.signed.sbsign /boot/vmlinuz-3.16.0-rc3+

Patch details:

Well all the hard work is done in previous patches.  Now bzImage loader
has just call into that code and verify whether bzImage signature are
valid or not.

Also create two config options.  First one is CONFIG_KEXEC_VERIFY_SIG.
This option enforces that kernel has to be validly signed otherwise kernel
load will fail.  If this option is not set, no signature verification will
be done.  Only exception will be when secureboot is enabled.  In that case
signature verification should be automatically enforced when secureboot is
enabled.  But that will happen when secureboot patches are merged.

Second config option is CONFIG_KEXEC_BZIMAGE_VERIFY_SIG.  This option
enables signature verification support on bzImage.  If this option is not
set and previous one is set, kernel image loading will fail because kernel
does not have support to verify signature of bzImage.

Signed-off-by: Vivek Goyal 
Cc: Borislav Petkov 
Cc: Michael Kerrisk 
Cc: Yinghai Lu 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Cc: Matthew Garrett 
Cc: Greg Kroah-Hartman 
Cc: Dave Young 
Cc: WANG Chao 
Cc: Baoquan He 
Cc: Andy Lutomirski 
Cc: Matt Fleming 
Cc: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: support for kexec on panic using new system call

2014-08-08T22:57:33+00:00

This patch adds support for loading a kexec on panic (kdump) kernel usning
new system call.

It prepares ELF headers for memory areas to be dumped and for saved cpu
registers.  Also prepares the memory map for second kernel and limits its
boot to reserved areas only.

Signed-off-by: Vivek Goyal 
Cc: Borislav Petkov 
Cc: Michael Kerrisk 
Cc: Yinghai Lu 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Cc: Matthew Garrett 
Cc: Greg Kroah-Hartman 
Cc: Dave Young 
Cc: WANG Chao 
Cc: Baoquan He 
Cc: Andy Lutomirski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec-bzImage64: support for loading bzImage using 64bit entry

2014-08-08T22:57:33+00:00

This is loader specific code which can load bzImage and set it up for
64bit entry.  This does not take care of 32bit entry or real mode entry.

32bit mode entry can be implemented if somebody needs it.

Signed-off-by: Vivek Goyal 
Cc: Borislav Petkov 
Cc: Michael Kerrisk 
Cc: Yinghai Lu 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Cc: Matthew Garrett 
Cc: Greg Kroah-Hartman 
Cc: Dave Young 
Cc: WANG Chao 
Cc: Baoquan He 
Cc: Andy Lutomirski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: load and relocate purgatory at kernel load time

2014-08-08T22:57:32+00:00

Load purgatory code in RAM and relocate it based on the location.
Relocation code has been inspired by module relocation code and purgatory
relocation code in kexec-tools.

Also compute the checksums of loaded kexec segments and store them in
purgatory.

Arch independent code provides this functionality so that arch dependent
bootloaders can make use of it.

Helper functions are provided to get/set symbol values in purgatory which
are used by bootloaders later to set things like stack and entry point of
second kernel etc.

Signed-off-by: Vivek Goyal 
Cc: Borislav Petkov 
Cc: Michael Kerrisk 
Cc: Yinghai Lu 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Cc: Matthew Garrett 
Cc: Greg Kroah-Hartman 
Cc: Dave Young 
Cc: WANG Chao 
Cc: Baoquan He 
Cc: Andy Lutomirski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kexec: implementation of new syscall kexec_file_load

2014-08-08T22:57:32+00:00

Previous patch provided the interface definition and this patch prvides
implementation of new syscall.

Previously segment list was prepared in user space.  Now user space just
passes kernel fd, initrd fd and command line and kernel will create a
segment list internally.

This patch contains generic part of the code.  Actual segment preparation
and loading is done by arch and image specific loader.  Which comes in
next patch.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vivek Goyal 
Cc: Borislav Petkov 
Cc: Michael Kerrisk 
Cc: Yinghai Lu 
Cc: Eric Biederman 
Cc: H. Peter Anvin 
Cc: Matthew Garrett 
Cc: Greg Kroah-Hartman 
Cc: Dave Young 
Cc: WANG Chao 
Cc: Baoquan He 
Cc: Andy Lutomirski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds