Commit Graph

11 Commits

Author SHA1 Message Date
Arnd Bergmann 4ae987894c s390: fix clang -Wpointer-sign warnigns in boot code
The arch/s390/boot directory is built with its own set of compiler
options that does not include -Wno-pointer-sign like the rest of
the kernel does, this causes a lot of harmless but correct warnings
when building with clang.

For the atomics, we can add type casts to avoid the warnings, for
everything else the easiest way is to slightly adapt the types
to be more consistent.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-05-03 17:17:58 +02:00
Gerald Schaefer b2d24b97b2 s390/kernel: add support for kernel address space layout randomization (KASLR)
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 <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29 10:47:10 +02:00
Martin Schwidefsky 5f1207fbe7 s390/ipl: provide uapi header for list directed IPL
The IPL parameter block is used as an interface between Linux and
the machine to query and change the boot device and boot options.
To be able to create IPL parameter block in user space and pass it
as segment to kexec provide an uapi header with proper structure
definitions for the block.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26 12:34:05 +02:00
Martin Schwidefsky 86c74d869d s390/ipl: make ipl_info less confusing
The ipl_info union in struct ipl_parameter_block has the same name as
the struct ipl_info. This does not help while reading the code and the
union in struct ipl_parameter_block does not need to be named. Drop
the name from the union.

Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-26 12:34:05 +02:00
Vasily Gorbik 093ddccb55 s390/protvirt: block kernel command line alteration
Disallow kernel command line alteration via ipl parameter block if
running in protected virtualization environment.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10 17:47:22 +02:00
Vasily Gorbik db9492cef4 s390/protvirt: add memory sharing for diag 308 set/store
Add sharing of ipl parameter block for diag 308 set/store calls to allow
kvm access in protected virtualization environment.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10 17:47:22 +02:00
Vasily Gorbik 1e941d3949 s390: move ipl block to .boot.preserved.data section
.boot.preserved.data is a better fit for ipl block than .boot.data
which is discarded after init. Reusing .boot.preserved.data allows to
simplify code a little bit and avoid copying data from .boot.data to
persistent variables.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10 17:47:11 +02:00
Vasily Gorbik 6d85dac2ab s390: warn about clearing als implied facilities
Add a warning about removing required architecture level set facilities
via "facilities=" command line option.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-01 08:00:42 +01:00
Vasily Gorbik b5e804598d s390: allow overriding facilities via command line
Add "facilities=" command line option which allows to override
facility bits returned by stfle. The main purpose of that is debugging
aids which allows to test specific kernel behaviour depending on
specific facilities presence. It also affects CPU alternatives.

"facilities=" command line option format is comma separated list of
integer values to be additionally set or cleared (if value is starting
with "!"). Values ranges are also supported. e.g.:

facilities=!130-160,159,167-169

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-03-01 08:00:41 +01:00
Vasily Gorbik d58106c3ec s390/kasan: use noexec and large pages
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 <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:24 +02:00
Vasily Gorbik 49698745e5 s390: move ipl block and cmd line handling to early boot phase
To distinguish zfcpdump case and to be able to parse some of the kernel
command line arguments early (e.g. mem=) ipl block retrieval and command
line construction code is moved to the early boot phase.

"memory_end" is set up correctly respecting "mem=" and hsa_size in case
of the zfcpdump.

arch/s390/boot/string.c is introduced to provide string handling and
command line parsing functions to early boot phase code for the compressed
kernel image case.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:14 +02:00