Sven Schnelle reported that setting CLOCKSOURCE_VALIDATE_LAST_CYCLE
doesn't make sense: even if our tod clock overflows delta calculation
(now - last) with unsigned 64 bit values will still be correct.
Therefore revert commit 555701a714 ("s390/time: select
CLOCKSOURCE_VALIDATE_LAST_CYCLE").
Fixes: 555701a714 ("s390/time: select CLOCKSOURCE_VALIDATE_LAST_CYCLE")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The value returned by read_tod_clock() will overflow on September 17th 2042.
To avoid that system time jumps back select CLOCKSOURCE_VALIDATE_LAST_CYCLE
which enables a sanity check in order to prevent negative "delta" values.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Get rid of FORCE_MAX_ZONEORDER which limited allocations to order 8 (= 1MB)
and use the default, which allows for order 10 (= 4MB) allocations.
Given that s390 allows less than the default this caused some memory
allocation problems more or less unique to s390 from time to time.
Note: this was originally introduced with commit 684de39bd7 ("[S390]
Fix IPL from NSS.") in order to support Named Saved Segments, which
could start/end at an arbitrary 1 megabyte boundary and also before
support for sparsemem vmemmmap was enabled.
Since NSS support is gone, but sparsemem vmemmap support is available
this limitation can go away.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Trimming to MAX_ORDER was originally done in order to avoid to set
HOLES_IN_ZONE, which in turn would enable a quite expensive
pfn_valid() check. pfn_valid() however only checks if a struct page
exists for a given pfn.
With sparsemen vmemmap there are always struct pages, since memmaps
are allocated for whole sections. Therefore remove the HOLES_IN_ZONE
comment and the trimming.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
There is no interface to userspace which exposes anything that would
require the struct __debug_entry definition. Therefore remove it from
uapi. This allows to change the definition, since it is only kernel
internally used.
The only exception is the crash utility, however that tool must handle
changes all the time anyway.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
There is not a single user of the debug raw view. Therefore remove it
before anybody uses it. If anybody would make use of the view it would
expose the struct __debug_entry definition to userspace and really
would make it uapi. This wouldn't be good, since the definition is
suboptimal and needs to be changed.
Right now the structure definition is only defined to be uapi, however
there is no user.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Qian Cai reported:
"""
When NUMA=n and nr_node_ids=2, in apply_wqattrs_prepare(), it has,
for_each_node(node) {
if (wq_calc_node_cpumask(...
where it will trigger a booting warning,
WARNING: workqueue cpumask: online intersect > possible intersect
because it found 2 nodes and wq_numa_possible_cpumask[1] is an empty
cpumask.
"""
Let NODES_SHIFT depend on NEED_MULTIPLE_NODES like it is done
on other architectures in order to fix this.
Fixes: 701dc81e74 ("s390/mm: remove fake numa support")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
ARCH_SAVE_PAGE_KEYS has been introduced in order to be able to save
and restore s390 specific storage keys into a hibernation image.
With hibernation support removed from s390 there is no point in
keeping the callbacks.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Hibernation is known to be broken for many years on s390. Given that
there aren't any real use cases, remove the code instead of spending
time to fix and maintain it.
Without hibernate support it doesn't make too much sense to keep power
management support; therefore remove it completely.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
It turned out that fake numa support is rather useless on s390, since
there are no scenarios where there is any performance or other benefit
when used.
However it does provide maintenance cost and breaks from time to time.
Therefore remove it.
CONFIG_NUMA is still supported with a very small backend and only one
node. This way userspace applications which require NUMA interfaces
continue to work.
Note that NODES_SHIFT is set to 1 (= 2 nodes) instead of 0 (= 1 node),
since there is quite a bit of kernel code which assumes that more than
one node is possible if CONFIG_NUMA is enabled.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
diag 0x44 is a voluntary undirected yield of a virtual CPU. This has
caused a lot of performance issues in the past.
There is only one caller left, and that one is only executed if diag
0x9c (directed yield) is not present. Given that all hypervisors
implement diag 0x9c anyway, remove the last diag 0x44 to avoid that
more callers will be added.
Worst case that could happen now, if diag 0x9c is not present, is that
a virtual CPU would loop a bit instead of giving its time slice up.
diag 0x44 statistics in debugfs are kept and will always be zero, so
that user space can tell that there are no calls.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Remove compat vdso code, since there is hardly any compat user space
left. Still existing compat user space will have to use system calls
instead.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
getcpu reads the required values for cpu and node with two
instructions. This might lead to an inconsistent result if user space
gets preempted and migrated to a different CPU between the two
instructions.
Fix this by using just a single instruction to read both values at
once.
This is currently rather a theoretical bug, since there is no real
NUMA support available (except for NUMA emulation).
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
When a secondary CPU is brought up it must initialize its control
registers. CPU A which triggers that a secondary CPU B is brought up
stores its control register contents into the lowcore of new CPU B,
which then loads these values on startup.
This is problematic in various ways: the control register which
contains the home space ASCE will correctly contain the kernel ASCE;
however control registers for primary and secondary ASCEs are
initialized with whatever values were present in CPU A.
Typically:
- the primary ASCE will contain the user process ASCE of the process
that triggered onlining of CPU B.
- the secondary ASCE will contain the percpu VDSO ASCE of CPU A.
Due to lazy ASCE handling we may also end up with other combinations.
When then CPU B switches to a different process (!= idle) it will
fixup the primary ASCE. However the problem is that the (wrong) ASCE
from CPU A was loaded into control register 1: as soon as an ASCE is
attached (aka loaded) a CPU is free to generate TLB entries using that
address space.
Even though it is very unlikey that CPU B will actually generate such
entries, this could result in TLB entries of the address space of the
process that ran on CPU A. These entries shouldn't exist at all and
could cause problems later on.
Furthermore the secondary ASCE of CPU B will not be updated correctly.
This means that processes may see wrong results or even crash if they
access VDSO data on CPU B. The correct VDSO ASCE will eventually be
loaded on return to user space as soon as the kernel executed a call
to strnlen_user or an atomic futex operation on CPU B.
Fix both issues by intializing the to be loaded control register
contents with the correct ASCEs and also enforce (re-)loading of the
ASCEs upon first context switch and return to user space.
Fixes: 0aaba41b58 ("s390: remove all code using the access register mode")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
If an SMT capable system is not IPL'ed from the first CPU the setup of
the physical to logical CPU mapping is broken: the IPL core gets CPU
number 0, but then the next core gets CPU number 1. Correct would be
that all SMT threads of CPU 0 get the subsequent logical CPU numbers.
This is important since a lot of code (like e.g. the CPU topology
code) assumes that CPU maps are setup like this. If the mapping is
broken the system will not IPL due to broken topology masks:
[ 1.716341] BUG: arch topology broken
[ 1.716342] the SMT domain not a subset of the MC domain
[ 1.716343] BUG: arch topology broken
[ 1.716344] the MC domain not a subset of the BOOK domain
This scenario can usually not happen since LPARs are always IPL'ed
from CPU 0 and also re-IPL is intiated from CPU 0. However older
kernels did initiate re-IPL on an arbitrary CPU. If therefore a re-IPL
from an old kernel into a new kernel is initiated this may lead to
crash.
Fix this by setting up the physical to logical CPU mapping correctly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The idle time reported in /proc/stat sometimes incorrectly contains
huge values on s390. This is caused by a bug in arch_cpu_idle_time().
The kernel tries to figure out when a different cpu entered idle by
accessing its per-cpu data structure. There is an ordering problem: if
the remote cpu has an idle_enter value which is not zero, and an
idle_exit value which is zero, it is assumed it is idle since
"now". The "now" timestamp however is taken before the idle_enter
value is read.
Which in turn means that "now" can be smaller than idle_enter of the
remote cpu. Unconditionally subtracting idle_enter from "now" can thus
lead to a negative value (aka large unsigned value).
Fix this by moving the get_tod_clock() invocation out of the
loop. While at it also make the code a bit more readable.
A similar bug also exists for show_idle_time(). Fix this is as well.
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This function must be inlined since any caller expects the current
stack pointer; which wouldn't be true if the function isn't inlined.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The current implementation of get_clock_monotonic() leaves it up to
the caller to call the function with preemption disabled. The only
core kernel caller (sched_clock) however does not disable preemption.
In order to make sure that all callers of this function see monotonic
values handle disabling preemption within the function itself.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This is the s390 version of commit 40576e5e63 ("x86: alternative.h:
use asm_inline for all alternative variants").
See commit eb11186930 ("compiler-types.h: add asm_inline
definition") for more details.
With this change the compiler will not generate many out-of-line
versions for the three instruction sized arch_spin_unlock() function
anymore. Due to this gcc seems to change a lot of other inline
decisions which results in a net 6k text size growth according to
bloat-o-meter (gcc 9.2 with defconfig).
But that's still better than having many out-of-line versions of
arch_spin_unlock().
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This is the s390 version of commit 32ee8230b2 ("x86: bug.h: use
asm_inline in _BUG_FLAGS definitions").
See commit eb11186930 ("compiler-types.h: add asm_inline
definition") for more details.
Just like on x86 the .text section size decreases a bit while the
.data section size increases about the same amount (gcc 9.2 with
defconfig).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The names for the z13s and z14 ZR1 machines are missing for the
TUNE_Z13 and TUNE_Z14 descriptions. Just add them.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Make use of 'depends on cc-option' to only display those Kconfig
options for which compiler support is available.
Add this for the MARCH and TUNE options which are the only options
which may result in compile errors if the selected architecture is not
supported by the compiler.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
__insn32_query() will not compile if the compiler decides to not
inline it, since it contains an inline assembly with an "i" constraint
with variable contents.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The inline assembly constraints of __insn32_query() tell the compiler
that only the first byte of "query" is being written to. Intended was
probably that 32 bytes are written to.
Fix and simplify the code and just use a "memory" clobber.
Fixes: d668139718 ("KVM: s390: provide query function for instructions returning 32 byte")
Cc: stable@vger.kernel.org # v5.2+
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Always inline asm inlines with variable operands for "i" constraints,
since they won't compile if the compiler would decide to not inline
them.
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Always inline asm inlines with variable operands for "i" constraints,
since they won't compile if the compiler would decide to not inline
them.
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Always inline asm inlines with variable operands for "i" constraints,
since they won't compile if the compiler would decide to not inline
them.
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Always inline asm inlines with variable operands for "i" constraints,
since they won't compile if the compiler would decide to not inline
them.
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Always inline asm inlines with variable operands for "i" constraints,
since they won't compile if the compiler would decide to not inline
them.
Reported-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This file would need a lot of work to make sense again. Thomas Huth
started working on that four years ago, but that wasn't finished.
Therefore remove this.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
The contents of the file is completely outdated - just remove it.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
s390 does not map the vdso for statically linked binaries, assuming
that this doesn't make sense. See commit fc5243d98a ("[S390]
arch_setup_additional_pages arguments").
However with glibc commit d665367f596d ("linux: Enable vDSO for static
linking as default (BZ#19767)") and commit 5e855c895401 ("s390: Enable
VDSO for static linking") the vdso is also used for statically linked
binaries - if the kernel would make it available.
Therefore map the vdso always, just like all other architectures.
Reported-by: Stefan Liebler <stli@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Masahiro Yamada changed the zcrypt.h header file to use __u{16,32,64}
instead of uint{16,32,64}_t with ("s390: use __u{16,32,64} instead of
uint{16,32,64}_t in uapi header").
This makes all s390 header files pass - remove zcrypt.h from the blacklist.
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
The stfle inline assembly returns the number of double words written
(condition code 0) or the double words it would have written
(condition code 3), if the memory array it got as parameter would have
been large enough.
The current stfle implementation assumes that the array is always
large enough and clears those parts of the array that have not been
written to with a subsequent memset call.
If however the array is not large enough memset will get a negative
length parameter, which means that memset clears memory until it gets
an exception and the kernel crashes.
To fix this simply limit the maximum length. Move also the inline
assembly to an extra function to avoid clobbering of register 0, which
might happen because of the added min_t invocation together with code
instrumentation.
The bug was introduced with commit 14375bc4eb ("[S390] cleanup
facility list handling") but was rather harmless, since it would only
write to a rather large array. It became a potential problem with
commit 3ab121ab18 ("[S390] kernel: Add z/VM LGR detection"). Since
then it writes to an array with only four double words, while some
machines already deliver three double words. As soon as machines have
a facility bit within the fifth double a crash on IPL would happen.
Fixes: 14375bc4eb ("[S390] cleanup facility list handling")
Cc: <stable@vger.kernel.org> # v2.6.37+
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Replace defconfig with performance_defconfig. defconfig had some more
or less random debug options enabled, where nobody knows why anymore.
Just remove the old defconfig and replace it with performance_defconfig,
which reduces the number of configs to maintain. A config with debugging
options enabled is debug_defconfig which is supposed to be rather close
to performance_defconfig except that is has debug options enabled.
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
stop_machine is the only user left of cpu_relax_yield. Given that it
now has special semantics which are tied to stop_machine introduce a
weak stop_machine_yield function which architectures can override, and
get rid of the generic cpu_relax_yield implementation.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Move the CONFIG_CRASH_DUMP ifdef to get rid of this:
arch/s390/kernel/machine_kexec.c:146:22: warning: 'do_start_kdump' defined but not used [-Wunused-function]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Get rid of gcc9 warnings like this:
arch/s390/boot/ipl_report.c: In function 'find_bootdata_space':
arch/s390/boot/ipl_report.c:42:26: warning: taking address of packed member of 'struct ipl_rb_components' may result in an unaligned pointer value [-Waddress-of-packed-member]
42 | for_each_rb_entry(comp, comps)
| ^~~~~
This is effectively the s390 variant of commit 20c6c18904
("x86/boot: Disable the address-of-packed-member compiler warning").
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Get rid of gcc9 warnings like this:
arch/s390/boot/ipl_report.c: In function 'find_bootdata_space':
arch/s390/boot/ipl_report.c:42:26: warning: taking address of packed member of 'struct ipl_rb_components' may result in an unaligned pointer value [-Waddress-of-packed-member]
42 | for_each_rb_entry(comp, comps)
| ^~~~~
This is effectively the s390 variant of commit 20c6c18904
("x86/boot: Disable the address-of-packed-member compiler warning").
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
x86 and powerpc (partially) enforce already CONFIG_HOTPLUG_CPU. On
s390 it is enabled on all distributions by default since ages.
The only exception is our zfcpdump kernel.
However to simplify testing, enforce HOTPLUG_CPU. This was suggested
by Paul McKenney, since his rcutorture test environments for CONFIG_SMP=y
only support HOTPLUG_CPU=y.
Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
There never have been distributions that shiped with CONFIG_SMP=n for
s390. In addition the kernel currently doesn't even compile with
CONFIG_SMP=n for s390. Most likely it wouldn't even work, even if we
fix the compile error, since nobody tests it, since there is no use
case that I can think of.
Therefore simply enforce CONFIG_SMP and get rid of some more or
less unused code.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
After two decades of significant contributions to the s390
architecture, we must say goodbye to our dear colleague.
Blue skies, Martin!
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Commit 626a5f66da ("s390: bpf: implement jitting of JMP32") added
JMP32 code-gen support for s390. However it triggers the warning below
due to some unusual gotos in the original s390 bpf jit code.
Add a couple of additional "is_jmp32" initializations to fix this.
Also fix the wrong opcode for the "llilf" instruction that was
introduced with the same commit.
arch/s390/net/bpf_jit_comp.c: In function 'bpf_jit_insn':
arch/s390/net/bpf_jit_comp.c:248:55: warning: 'is_jmp32' may be used uninitialized in this function [-Wmaybe-uninitialized]
_EMIT6(op1 | reg(b1, b2) << 16 | (rel & 0xffff), op2 | mask); \
^
arch/s390/net/bpf_jit_comp.c:1211:8: note: 'is_jmp32' was declared here
bool is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32;
Fixes: 626a5f66da ("s390: bpf: implement jitting of JMP32")
Cc: Jiong Wang <jiong.wang@netronome.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Jiong Wang <jiong.wang@netronome.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When converting to autogenerated compat syscall wrappers all system
call entry points got a different symbol name: they all got a __s390x_
prefix.
This caused breakage with system call tracing, since an appropriate
arch_syscall_match_sym_name() was not provided. Add this function, and
while at it also add code to avoid compat system call tracing. s390
has different system call tables for native 64 bit system calls and
compat system calls. This isn't really supported in the common
code. However there are hardly any compat binaries left, therefore
just ignore compat system calls, like x86 and arm64 also do for the
same reason.
Fixes: aa0d6e70d3 ("s390: autogenerate compat syscall wrappers")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Fix this allnoconfig build breakage:
arch/s390/boot/mem_detect.c: In function 'tprot':
arch/s390/boot/mem_detect.c:122:12: error: 'EFAULT' undeclared (first use in this function)
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With pointer obfuscation the output of show_registers() became quite useless:
Krnl PSW : (____ptrval____) (____ptrval____) (__list_add_valid+0x98/0xa8)
In order to print the psw mask and address use %px instead of %p.
And the output looks again like this:
Krnl PSW : 0404d00180000000 00000000007c0dd0 (__list_add_valid+0x98/0xa8)
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
git commit cafa0010cd ("Raise the minimum required gcc version to 4.6")
raised the minimum gcc version to 4.6. Therefore remove the s390 specific
gcc 4.3 version check, which wasn't sufficient anyway.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Get rid of this compile warning for !PROC_FS:
CC arch/s390/kernel/sysinfo.o
arch/s390/kernel/sysinfo.c:275:12: warning: 'sysinfo_show' defined but not used [-Wunused-function]
static int sysinfo_show(struct seq_file *m, void *v)
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin 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: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
memmove_early was introduced with commit d543a106f9 ("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 d08091ac96
("s390/ipl: rely on diag308 store to get ipl info") and
commit b4623d4e5b ("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: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin 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 2dea1d9c38 ("powerpc/uprobes: Implement
arch_uretprobe_is_alive()") for more details.
With this implemented all test cases referenced in the above commit
pass.
Reported-by: Ziqian SUN <zsun@redhat.com>
Cc: <stable@vger.kernel.org> # v4.3+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin 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: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Provide base_asce_alloc() and base_asce_free() helper functions which
can be used to allocate an ASCE and all required region, segment and
page tables required to access memory regions of the virtual kernel
address space.
Both, the ASCE and all tables, do not use any features that correspond
to e.g. enhanced DAT features. This is required for some I/O functions
that pass an ASCE, like e.g. some service call requests, but which may
not use any enhanced features.
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Acked-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit df04abfd18 ("fs/proc/kcore.c: Add bounce buffer for ktext
data") added a bounce buffer to avoid hardened usercopy checks. Copying
to the bounce buffer was implemented with a simple memcpy() assuming
that it is always valid to read from kernel memory iff the
kern_addr_valid() check passed.
A simple, but pointless, test case like "dd if=/proc/kcore of=/dev/null"
now can easily crash the kernel, since the former execption handling on
invalid kernel addresses now doesn't work anymore.
Also adding a kern_addr_valid() implementation wouldn't help here. Most
architectures simply return 1 here, while a couple implemented a page
table walk to figure out if something is mapped at the address in
question.
With DEBUG_PAGEALLOC active mappings are established and removed all the
time, so that relying on the result of kern_addr_valid() before
executing the memcpy() also doesn't work.
Therefore simply use probe_kernel_read() to copy to the bounce buffer.
This also allows to simplify read_kcore().
At least on s390 this fixes the observed crashes and doesn't introduce
warnings that were removed with df04abfd18 ("fs/proc/kcore.c: Add
bounce buffer for ktext data"), even though the generic
probe_kernel_read() implementation uses uaccess functions.
While looking into this I'm also wondering if kern_addr_valid() could be
completely removed...(?)
Link: http://lkml.kernel.org/r/20171202132739.99971-1-heiko.carstens@de.ibm.com
Fixes: df04abfd18 ("fs/proc/kcore.c: Add bounce buffer for ktext data")
Fixes: f5509cc18d ("mm: Hardened usercopy")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add the signum system call parameter for documentation purposes only,
and without checking if the passed value is a valid real-time signal.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The man page for the s390_runtime_instr() system call refers to a
header file that was never exported. Therefore it's time to finally
provide the header file, and move large parts of the runtime
instrumentation header file to a new uapi header file.
Reported-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The 64 bit system call table contains three entries that come without
a matching NR_<name> entry in unistd.h. In fact all three of them do
not make sense on 64 bit, but only for compat processes.
llseek and mmap2 were specifically introduced for 32 bit / compat
processes. getrlimit is wired up twice, so that only the entry that
comes with a corresponding NR_getrlimit needs to be kept.
The other entries can be removed, since it seems very unlikely that
this will break user space.
Reported-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Michal Suchánek reported the following compile error with
FORTIFY_SOURCE enabled:
drivers/s390/char/sclp_early_core.o: In function `memcpy':
include/linux/string.h:340: undefined reference to `fortify_panic'
To fix this simply disable FORTIFY_SOURCE on the early sclp code as
well, which I forgot on the initial commit.
Fixes: 79962038df ("s390: add support for FORTIFY_SOURCE")
Reported-by: Michal Suchánek <msuchanek@suse.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When wiring up the socket system calls the compat entries were
incorrectly set. Not all of them point to the corresponding compat
wrapper functions, which clear the upper 33 bits of user space
pointers, like it is required.
Fixes: 977108f89c ("s390: wire up separate socketcalls system calls")
Cc: <stable@vger.kernel.org> # v4.3+
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Martin Cermak reported that setting a uprobe doesn't work. Reason for
this is that the common uprobes code tries to get an unmapped area at
the last possible page within an address space.
This broke with commit 1aea9b3f92 ("s390/mm: implement 5 level pages
tables") which introduced an off-by-one bug which prevents to map
anything at the last possible page within an address space.
The check with the off-by-one bug however can be removed since with
commit 8ab867cb08 ("s390/mm: fix BUG_ON in crst_table_upgrade") the
necessary check is done at both call sites.
Reported-by: Martin Cermak <mcermak@redhat.com>
Bisected-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Fixes: 1aea9b3f92 ("s390/mm: implement 5 level pages tables")
Cc: <stable@vger.kernel.org> # v4.13+
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The switch_to() macro has an optimization to avoid saving and
restoring register contents that aren't needed for kernel threads.
There is however the possibility that a kernel thread execve's a user
space program. In such a case the execve'd process can partially see
the contents of the previous process, which shouldn't be allowed.
To avoid this, simply always save and restore register contents on
context switch.
Cc: <stable@vger.kernel.org> # v2.6.37+
Fixes: fdb6d070ef ("switch_to: dont restore/save access & fpu regs for kernel threads")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When searching the opcode offset table within find_insn() the check
"entry->opcode == 0" was intended to clarify that 1-byte opcodes, the
first one being 0, are special.
However there is no mnemonic for an illegal opcode starting with 0.
Therefore there is also no opcode offset table entry that matches,
which again means that the check never is true. Therefore just remove
the confusing check, and add a comment which hopefully explains how
this works.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If GCC_PLUGIN_RANDSTRUCT is enabled the members of task_struct will be
shuffled around. The offsets of the "pid" and "stack" members within
task_struct may not necessarily fit into 12 bits anymore, which causes
compile errors within __switch_to, since instructions are used, which
only have a 12 bit displacement field.
Therefore rework __switch_to, to allow for larger offsets.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove unused parameter from the call function,
which I accidentally added.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With support for perf_regs and libdw, you can record and report
call graphs for user space programs. Simply invoke perf with
the --call-graph=dwarf command line option.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
[brueckner: added dwfl_thread_state_register_pc() call]
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Heiko Carstens