linux-stable.git/arch/s390/include/asm/setup.h, branch linux-5.2.y

s390/kernel: add support for kernel address space layout randomization (KASLR)

2019-04-29T08:47:10+00:00

This patch adds support for relocating the kernel to a random address.
The random kernel offset is obtained from cpacf, using either TRNG, PRNO,
or KMC_PRNG, depending on supported MSA level.

KERNELOFFSET is added to vmcoreinfo, for crash --kaslr support.

Signed-off-by: Gerald Schaefer 
Reviewed-by: Philipp Rudo 
Signed-off-by: Martin Schwidefsky

s390/sclp: do not use static sccbs

2019-04-29T08:47:10+00:00

The sccbs for init/read/sdias/early have to be located below 2 GB, and
they are currently defined as a static buffer.

With a relocatable kernel that could reside at any place in memory, this
will no longer guarantee the location below 2 GB, so use a dynamic
GFP_DMA allocation instead.

The sclp_early_sccb buffer needs special handling, as it can be used
very early, and by both the decompressor and also the decompressed
kernel. Therefore, a fixed 4 KB buffer is introduced at 0x11000, the
former PARMAREA_END. The new PARMAREA_END is now 0x12000, and it is
renamed to HEAD_END, as it is rather the end of head.S and not the end
of the parmarea.

Signed-off-by: Gerald Schaefer 
Reviewed-by: Philipp Rudo 
Signed-off-by: Martin Schwidefsky

s390/kexec_file: Simplify parmarea access

2019-04-29T08:43:57+00:00

Access the parmarea in head.S via a struct instead of individual offsets.

While at it make the fields in the parmarea .quads.

Signed-off-by: Philipp Rudo 
Signed-off-by: Martin Schwidefsky

s390/kasan: use noexec and large pages

2018-10-09T09:21:24+00:00

To lower memory footprint and speed up kasan initialisation detect
EDAT availability and use large pages if possible. As we know how
much memory is needed for initialisation, another simplistic large
page allocator is introduced to avoid memory fragmentation.

Since facilities list is retrieved anyhow, detect noexec support and
adjust pages attributes. Handle noexec kernel option to avoid inconsistent
kasan shadow memory pages flags.

Signed-off-by: Vasily Gorbik 
Signed-off-by: Martin Schwidefsky

s390/mem_detect: move tprot loop to early boot phase

2018-10-09T09:21:08+00:00

Move memory detection to early boot phase. To store online memory
regions "struct mem_detect_info" has been introduced together with
for_each_mem_detect_block iterator. mem_detect_info is later converted
to memblock.

Also introduces sclp_early_get_meminfo function to get maximum physical
memory and maximum increment number.

Reviewed-by: Heiko Carstens 
Reviewed-by: Martin Schwidefsky 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Martin Schwidefsky

s390/boot: block uncompressed vmlinux booting attempts

2018-07-02T09:25:05+00:00

Since the plain vmlinux ELF file no longer carries all necessary parts
for starting up (like the entry point and decompressor), add a check
which would block boot process and encourage users to use bzImage or
arch/s390/boot/compressed/vmlinux instead.

The check relies on s390 linux entry point ABI definition, which is only
present in bzImage and arch/s390/boot/compressed/vmlinux.

Reported-by: Guenter Roeck 
Tested-by: Guenter Roeck 
Acked-by: Cornelia Huck 
Acked-by: Christian Borntraeger 
Reviewed-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Martin Schwidefsky

s390/setup: do not reserve the decompressor code

2018-06-25T08:14:41+00:00

Introduce PARMAREA_END, and use it for memblock reserve of low
memory, which is used for lowcore, kdump data mover code and page
buffer, early stack and parmarea. There is no need to reserve an
area between PARMAREA_END and the decompressor _ehead.

Reviewed-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik 
Signed-off-by: Martin Schwidefsky

s390/kexec_file: Prepare setup.h for kexec_file_load

2018-04-16T07:10:21+00:00

kexec_file_load needs to prepare the new kernels before they are loaded.
For that it has to know the offsets in head.S, e.g. to register the new
command line. Unfortunately there are no macros right now defining those
offsets. Define them now.

Signed-off-by: Philipp Rudo 
Signed-off-by: Martin Schwidefsky

s390/lpp: use assembler alternatives for the LPP instruction

2018-03-28T06:38:28+00:00

With the new macros for CPU alternatives the MACHINE_FLAG_LPP check
around the LPP instruction can be optimized. After this is done the
flag can be removed.

Signed-off-by: Martin Schwidefsky

s390/cpum_sf: correctly set the PID and TID in perf samples

2017-11-16T14:06:17+00:00

The hardware sampler creates samples that are processed at a later
point in time.  The PID and TID values of the perf samples that are
created for hardware samples are initialized with values from the
current task.  Hence, the PID and TID values are not correct and
perf samples are associated with wrong processes.

The PID and TID values are obtained from the Host Program Parameter
(HPP) field in the basic-sampling data entries.  These PIDs are
valid in the init PID namespace.  Ensure that the PIDs in the perf
samples are resolved considering the PID namespace in which the
perf event was created.

To correct the PID and TID values in the created perf samples,
a special overflow handler is installed.  It replaces the default
overflow handler and does not become effective if any other
overflow handler is used.  With the special overflow handler most
of the perf samples are associated with the right processes.
For processes, that are no longer exist, the association might
still be wrong.

Signed-off-by: Hendrik Brueckner 
Signed-off-by: Martin Schwidefsky