linux.git/arch/s390/kernel/setup.c, branch v4.13

kexec: move vmcoreinfo out of the kernel's .bss section

2017-07-12T23:25:59+00:00

As Eric said,
 "what we need to do is move the variable vmcoreinfo_note out of the
  kernel's .bss section. And modify the code to regenerate and keep this
  information in something like the control page.

  Definitely something like this needs a page all to itself, and ideally
  far away from any other kernel data structures. I clearly was not
  watching closely the data someone decided to keep this silly thing in
  the kernel's .bss section."

This patch allocates extra pages for these vmcoreinfo_XXX variables, one
advantage is that it enhances some safety of vmcoreinfo, because
vmcoreinfo now is kept far away from other kernel data structures.

Link: http://lkml.kernel.org/r/1493281021-20737-1-git-send-email-xlpang@redhat.com
Signed-off-by: Xunlei Pang 
Tested-by: Michael Holzheu 
Reviewed-by: Juergen Gross 
Suggested-by: Eric Biederman 
Cc: Benjamin Herrenschmidt 
Cc: Dave Young 
Cc: Hari Bathini 
Cc: Mahesh Salgaonkar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

s390: add a system call for guarded storage

2017-03-22T07:14:25+00:00

This adds a new system call to enable the use of guarded storage for
user space processes. The system call takes two arguments, a command
and pointer to a guarded storage control block:

    s390_guarded_storage(int command, struct gs_cb *gs_cb);

The second argument is relevant only for the GS_SET_BC_CB command.

The commands in detail:

0 - GS_ENABLE
    Enable the guarded storage facility for the current task. The
    initial content of the guarded storage control block will be
    all zeros. After the enablement the user space code can use
    load-guarded-storage-controls instruction (LGSC) to load an
    arbitrary control block. While a task is enabled the kernel
    will save and restore the current content of the guarded
    storage registers on context switch.
1 - GS_DISABLE
    Disables the use of the guarded storage facility for the current
    task. The kernel will cease to save and restore the content of
    the guarded storage registers, the task specific content of
    these registers is lost.
2 - GS_SET_BC_CB
    Set a broadcast guarded storage control block. This is called
    per thread and stores a specific guarded storage control block
    in the task struct of the current task. This control block will
    be used for the broadcast event GS_BROADCAST.
3 - GS_CLEAR_BC_CB
    Clears the broadcast guarded storage control block. The guarded-
    storage control block is removed from the task struct that was
    established by GS_SET_BC_CB.
4 - GS_BROADCAST
    Sends a broadcast to all thread siblings of the current task.
    Every sibling that has established a broadcast guarded storage
    control block will load this control block and will be enabled
    for guarded storage. The broadcast guarded storage control block
    is used up, a second broadcast without a refresh of the stored
    control block with GS_SET_BC_CB will not have any effect.

Signed-off-by: Martin Schwidefsky

sched/headers: Prepare to move _init() prototypes from to

2017-03-02T07:42:40+00:00

But first introduce a trivial header and update usage sites.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:35+00:00

We are going to split  out of , which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder  file that just
maps to  to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

s390: get rid of MACHINE_HAS_PFMF and MACHINE_HAS_HPAGE

2017-02-17T06:41:01+00:00

Both MACHINE_HAS_PFMF and MACHINE_HAS_HPAGE are just an alias for
MACHINE_HAS_EDAT1. So simply use MACHINE_HAS_EDAT1 instead.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390: report new vector facilities

2017-02-08T13:13:24+00:00

Add hardware capability bits and feature tags to /proc/cpuinfo for
the "Vector Packed Decimal Facility" (tag "vxd" / hwcap bit 2^12)
and the "Vector Enhancements Facility 1" (tag "vxe" / hwcap bit 2^13).

Signed-off-by: Martin Schwidefsky

s390: use correct input data address for setup_randomness

2017-02-08T13:13:23+00:00

The current implementation of setup_randomness uses the stack address
and therefore the pointer to the SYSIB 3.2.2 block as input data
address. Furthermore the length of the input data is the number of
virtual-machine description blocks which is typically one.

This means that typically a single zero byte is fed to
add_device_randomness.

Fix both of these and use the address of the first virtual machine
description block as input data address and also use the correct
length.

Fixes: bcfcbb6bae64 ("s390: add system information as device randomness")
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390: make setup_randomness work

2017-02-07T06:27:10+00:00

Commit bcfcbb6bae64 ("s390: add system information as device
randomness") intended to add some virtual machine specific information
to the randomness pool.

Unfortunately it uses the page allocator before it is ready to use. In
result the page allocator always returns NULL and the setup_randomness
function never adds anything to the randomness pool.

To fix this use memblock_alloc and memblock_free instead.

Fixes: bcfcbb6bae64 ("s390: add system information as device randomness")
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/setup: call memblock_reserve only for size > 0

2017-01-16T06:27:53+00:00

reserve_initrd currently calls memblock_reserve even if the to be
reserved size is zero. Even though the memblock core code can handle
this correctly, it still yields confusing debug messages if
memblock debugging is enabled.
Therefore make sure to not call memblock_reserve with a size of zero.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/setup: reword printk messages

2016-12-14T15:33:40+00:00

Two of the messages introduced by the memblock conversion are reworded.

Signed-off-by: Martin Schwidefsky