s390 hardware supports the definition of a so-call Physical NETwork
IDentifier (short PNETID) per network device port. These PNETIDS
can be used to identify network devices that are attached to the same
physical network (broadcast domain).

This patch provides the interface to extract the PNETID of a port of
a device attached to the ccw-bus or pci-bus.

Parts of this patch are based on an initial implementation by
Thomas Richter.
Signed-off-by: NUrsula Braun <ubraun@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add a test to check if a given device is a ccwgroup device.
Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: NSebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

VMLINUX_SYMBOL() is no-op unless CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
is defined.  It has ever been selected only by BLACKFIN and METAG.
VMLINUX_SYMBOL() is unneeded for s390-specific code.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

There should not be a '.' at the end of the spectre syslog messages.
Remove them.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Introduce compile time check for files which should avoid using .bss
section, because of the following reasons:
- .bss section has not been zeroed yet,
- initrd has not been moved to a safe location and could be overlapping
with .bss section.
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Move functions which may not access bss section to extra file. This
makes it easier to verify that all early functions which may not rely
on an initialized bss section are not accessing it.
Reviewed-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use IS_ENABLED to get rid of an #ifdef statement.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

memmove_early was introduced with commit d543a106 ("s390: fix
initrd corruptions with gcov/kcov instrumented kernels"). The reason
for writing this extra memmove implementation was to be able to move
memory from an unknown location (aka SCSI IPL parameter block) to a
known location.

This had to done early before it was known if the SCSI IPL parameter
block pointer was valid or not, and therefore the memmove
implementation was supposed to be able to handle program checks.

The code has been changed and especially with commit d08091ac
("s390/ipl: rely on diag308 store to get ipl info") and
commit b4623d4e ("s390: provide memmove implementation") there
is no need to have a memmove version that can handle program checks,
and in addition it cannot be gcov/kcov instrumented anymore.
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The CPU Measurement sampling facility creates a trailer entry for each
Sample-Data-Block of stored samples. The trailer entry contains the sizes
(in bytes) of the stored sampling types:
 - basic-sampling data entry size
 - diagnostic-sampling data entry size
Both sizes are 2 bytes long.

This patch changes the trailer entry definition to reflect this.

Fixes: fcc77f50 ("s390/cpum_sf: Atomically reset trailer entry fields of sample-data-blocks")
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The s390 CPU measurement facility sampling mode supports basic entries
and diagnostic entries. Each entry has a valid bit to indicate the
status of the entry as valid or invalid.

This bit is bit 31 in the diagnostic entry, but the bit mask definition
refers to bit 30.

Fix this by making the reserved field one bit larger.

Fixes: 7e75fc3f ("s390/cpum_sf: Add raw data sampling to support the diagnostic-sampling function")
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Reviewed-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Correct a trinity finding for the perf_event_open() system call with
a perf event attribute structure that uses a frequency but has the
sampling frequency set to zero.  This causes a FP divide exception during
the sample rate initialization for the hardware sampling facility.

Fixes: 8c069ff4 ("s390/perf: add support for the CPU-Measurement Sampling Facility")
Cc: stable@vger.kernel.org # 3.14+
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NHendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The BPF JIT need safe guarding against spectre v2 in the sk_load_xxx
assembler stubs and the indirect branches generated by the JIT itself
need to be converted to expolines.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The BPF JIT uses a 'b <disp>(%r<x>)' instruction in the definition
of the sk_load_word and sk_load_half functions.

Add support for branch-on-condition instructions contained in the
thunk code of an expoline.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The inline assembly to call __do_softirq on the irq stack uses
an indirect branch. This can be replaced with a normal relative
branch.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Reviewed-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The nospec-branch.c file is compiled without the gcc options to
generate expoline thunks. The return branch of the sysfs show
functions cpu_show_spectre_v1 and cpu_show_spectre_v2 is an indirect
branch as well. These need to be compiled with expolines.

Move the sysfs functions for spectre reporting to a separate file
and loose an '.' for one of the messages.

Cc: stable@vger.kernel.org # 4.16
Fixes: d424986f ("s390: add sysfs attributes for spectre")
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The assember code in arch/s390/kernel uses a few more indirect branches
which need to be done with execute trampolines for CONFIG_EXPOLINE=y.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Reviewed-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The return from the ftrace_stub, _mcount, ftrace_caller and
return_to_handler functions is done with "br %r14" and "br %r1".
These are indirect branches as well and need to use execute
trampolines for CONFIG_EXPOLINE=y.

The ftrace_caller function is a special case as it returns to the
start of a function and may only use %r0 and %r1. For a pre z10
machine the standard execute trampoline uses a LARL + EX to do
this, but this requires *two* registers in the range %r1..%r15.
To get around this the 'br %r1' located in the lowcore is used,
then the EX instruction does not need an address register.
But the lowcore trick may only be used for pre z14 machines,
with noexec=on the mapping for the first page may not contain
instructions. The solution for that is an ALTERNATIVE in the
expoline THUNK generated by 'GEN_BR_THUNK %r1' to switch to
EXRL, this relies on the fact that a machine that supports
noexec=on has EXRL as well.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The return from the memmove, memset, memcpy, __memset16, __memset32 and
__memset64 functions are done with "br %r14". These are indirect branches
as well and need to use execute trampolines for CONFIG_EXPOLINE=y.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Reviewed-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The return from the crc32_le_vgfm_16/crc32c_le_vgfm_16 and the
crc32_be_vgfm_16 functions are done with "br %r14". These are indirect
branches as well and need to use execute trampolines for CONFIG_EXPOLINE=y.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Reviewed-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

To be able to use the expoline branches in different assembler
files move the associated macros from entry.S to a new header
nospec-insn.h.

While we are at it make the macros a bit nicer to use.

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix the following sparse complaints:

arch/s390/purgatory/purgatory.c:18:5: warning: symbol 'kernel_entry' was not declared. Should it be static?
arch/s390/purgatory/purgatory.c:19:5: warning: symbol 'kernel_type' was not declared. Should it be static?
arch/s390/purgatory/purgatory.c:21:5: warning: symbol 'crash_start' was not declared. Should it be static?
arch/s390/purgatory/purgatory.c:22:5: warning: symbol 'crash_size' was not declared. Should it be static?
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Change the following to y:

arch/s390/configs/performance_defconfig:262:warning: symbol value 'm' invalid for NF_TABLES_IPV4
arch/s390/configs/performance_defconfig:264:warning: symbol value 'm' invalid for NF_TABLES_ARP
arch/s390/configs/performance_defconfig:285:warning: symbol value 'm' invalid for NF_TABLES_IPV6
arch/s390/configs/performance_defconfig:306:warning: symbol value 'm' invalid for NF_TABLES_BRIDGE
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The main linker script vmlinux.lds.S for the kernel image merges
the expoline code patch tables into two section ".nospec_call_table"
and ".nospec_return_table". This is *not* done for the modules,
there the sections retain their original names as generated by gcc:
".s390_indirect_call", ".s390_return_mem" and ".s390_return_reg".

The module_finalize code has to check for the compiler generated
section names, otherwise no code patching is done. This slows down
the module code in case of "spectre_v2=off".

Cc: stable@vger.kernel.org # 4.16
Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches")
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

In a multi-threaded program any thread can call execve(). If this
is not done by the thread group leader, the de_thread() function
replaces the pid of the task that calls execve() with the pid of
thread group leader. If the task reaches user space again without
going over __switch_to() the sampling tag is still set to the old
pid.

Define the arch_setup_new_exec function to verify the task pid
and udpate the tag with LPP if it has changed.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Change the IBM z13/z14 counter names to be in sync with all other models.

Cc: stable@vger.kernel.org # v4.12+
Fixes: 3593eb94 ("s390/cpum_cf: add hardware counter support for IBM z14")
Fixes: 3fc7aceb ("s390/cpum_cf: add IBM z13 counter event names")
Signed-off-by: NAndré Wild <wild@linux.ibm.com>
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Implement s390 specific arch_uretprobe_is_alive() to avoid SIGSEGVs
observed with uretprobes in combination with setjmp/longjmp.

See commit 2dea1d9c ("powerpc/uprobes: Implement
arch_uretprobe_is_alive()") for more details.

With this implemented all test cases referenced in the above commit
pass.
Reported-by: NZiqian SUN <zsun@redhat.com>
Cc: <stable@vger.kernel.org> # v4.3+
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The struct sigaction for user space in arch/s390/include/uapi/asm/signal.h
is ill defined. The kernel uses two structures 'struct sigaction' and
'struct old_sigaction', the correlation in the kernel for both 31 and
64 bit is as follows

    sys_sigaction -> struct old_sigaction
    sys_rt_sigaction -> struct sigaction

The correlation of the (single) uapi definition for 'struct sigaction'
under '#ifndef __KERNEL__':

    31-bit: sys_sigaction -> uapi struct sigaction
    31-bit: sys_rt_sigaction -> no structure available

    64-bit: sys_sigaction -> no structure available
    64-bit: sys_rt_sigaction -> uapi struct sigaction

This is quite confusing. To make it a bit less confusing make the
uapi definition of 'struct sigaction' usable for sys_rt_sigaction for
both 31-bit and 64-bit.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The name debug_defconfig reflects what the config is actually good
for and should be less confusing.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This config is not needed anymore.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Just add the new machine type number to the two places that matter.

Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

ccflags-y has no effect (no code is built in that directory,
arch/s390/boot/compressed/Makefile defines its own KBUILD_CFLAGS).
Removing ccflags-y together with COMPILE_VERSION.
Reviewed-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix the following sparse warnings:
symbol 'cpu_show_spectre_v1' was not declared. Should it be static?
symbol 'cpu_show_spectre_v2' was not declared. Should it be static?
Signed-off-by: NSebastian Ott <sebott@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Commit 81796a3c ("s390/decompressor: trim uncompressed
image head during the build") introduced a new
file named vmlinux.bin.full in directory
arch/s390/boot/compressed.

Add this file to the list of ignored files so it does
not show up on git status.
Signed-off-by: NThomas Richter <tmricht@linux.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The config options for kexec are currently not under any menu directory. Up
until now this was not a problem as standard kexec is always compiled in
and thus does not create a menu entry. This changed when kexec_file_load
was enabled. Its config option requires a menu entry which, when added
beneath standard kexec option, appears on the main directory above "General
Setup". Thus move the whole block further down such that the entry in now
in "Processor type and features".

While at it also update the help text for kexec file.
Signed-off-by: NPhilipp Rudo <prudo@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add an ELF loader for kexec_file. The main task here is to do proper sanity
checks on the ELF file. Basically all other functionality was already
implemented for the image loader.
Signed-off-by: NPhilipp Rudo <prudo@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add support to load a crash kernel to the image loader. This requires
extending the purgatory.
Signed-off-by: NPhilipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Add an image loader for kexec_file_load. For simplicity first skip crash
support. The functions defined in machine_kexec_file will later be shared
with the ELF loader.
Signed-off-by: NPhilipp Rudo <prudo@linux.vnet.ibm.com>
Reviewed-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>