Facilities setup has to be done after "facilities" command line option
parsing, it might set extra or remove existing facilities bits for
testing purposes.
Fixes: bb1520d581 ("s390/mm: start kernel with DAT enabled")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
KASAN common code is able to handle memory hotplug and create KASAN shadow
memory on a fly. Online memory ranges are available from mem_detect,
use this information to avoid mapping KASAN shadow for standby memory.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
If kernel is build without KASAN support there is a chance that kernel
image is going to be positioned by KASLR code to overlap with identity
mapping page tables.
When kernel is build with KASAN support enabled memory which
is potentially going to be used for page tables and KASAN
shadow mapping is accounted for in KASLR with the use of
kasan_estimate_memory_needs(). Split this function and introduce
vmem_estimate_memory_needs() to cover decompressor's vmem identity
mapping page tables.
Fixes: bb1520d581 ("s390/mm: start kernel with DAT enabled")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Add a function to get online memory in total. It is supposed to be used
in the decompressor as well as during early kernel startup.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Introduce mem_detect_truncate() to cut any online memory ranges above
established identity mapping size, so that mem_detect users wouldn't
have to do it over and over again.
Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Allocation of mem_detect extended area was not considered neither
in commit 9641b8cc73 ("s390/ipl: read IPL report at early boot")
nor in commit b2d24b97b2 ("s390/kernel: add support for kernel address
space layout randomization (KASLR)"). As a result mem_detect extended
theoretically may overlap with ipl report or randomized kernel image
position. But as mem_detect code will allocate extended area only
upon exceeding 255 online regions (which should alternate with offline
memory regions) it is not seen in practice.
To make sure mem_detect extended area does not overlap with ipl report
or randomized kernel position extend usage of "safe_addr". Make initrd
handling and mem_detect extended area allocation code move it further
right and make KASLR takes in into consideration as well.
Fixes: 9641b8cc73 ("s390/ipl: read IPL report at early boot")
Fixes: b2d24b97b2 ("s390/kernel: add support for kernel address space layout randomization (KASLR)")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
In case sclp_early_get_memsize() fails but diag260() succeeds make sure
some sane value is returned. This error scenario is highly unlikely,
but this change makes system able to boot in such case.
Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Get rid of this sparse warning:
arch/s390/kernel/diag.c:69:29: warning: symbol '__diag8c_tmp_amode31' was not declared. Should it be static?
Fixes: fbaee7464f ("s390/tty3270: add support for diag 8c")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Compiling the kernel with CONFIG_KPROBES disabled, but CONFIG_RETHOOK
enabled, results in this sparse warning:
arch/s390/kernel/rethook.c:26:15: warning: no previous prototype for 'arch_rethook_trampoline_callback' [-Wmissing-prototypes]
26 | unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Add a local rethook header file similar to riscv to address this.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 1a280f48c0 ("s390/kprobes: replace kretprobe with rethook")
Link: https://lore.kernel.org/all/202302030102.69dZIuJk-lkp@intel.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Kasan shadow memory area has been moved to the end of kernel address
space since commit 9a39abb7c9 ("s390/boot: simplify and fix kernel
memory layout setup"), therefore skipping any memory ranges above
VMALLOC_START in empty page tables cleanup code already handles
KASAN shadow memory intersection case and explicit checks could be
removed.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Commit b9ff81003c ("s390/vmem: cleanup empty page tables") introduced
empty page tables cleanup in vmem code, but when the kernel is built
with KASAN enabled the code has no effect due to wrong KASAN shadow
memory intersection condition, which effectively ignores any memory
range below KASAN shadow. Fix intersection condition to make code
work as anticipated.
Fixes: b9ff81003c ("s390/vmem: cleanup empty page tables")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Kasan shadow memory area has been moved to the end of kernel address
space since commit 9a39abb7c9 ("s390/boot: simplify and fix kernel
memory layout setup"). Change kasan memory layout note accordingly.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Currently if for some reason sclp_early_read_info() fails,
sclp_early_get_memsize() will not set max_physmem_end and it
will stay uninitialized. Any garbage value other than 0 will lead
to detect_memory() taking wrong path or returning a garbage value
as max_physmem_end. To avoid that simply initialize max_physmem_end.
Fixes: 73045a08cf ("s390: unify identity mapping limits handling")
Reported-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
In the current code each reipl type implements its own pair of loadparm
show/store functions. Add a macro to deduplicate the code a bit.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Fixes: 87fd22e0ae ("s390/ipl: add eckd support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Function __get_mem_detect_block() resets start and end
output parameters in case of invalid mem_detect array
index is provided. That violates the rule of sparing
the output on fail path and leads e.g to a below anomaly:
for_each_mem_detect_block(i, &start, &end)
continue;
One would expect start and end contain addresses of the
last memory block (if available), but in fact the two
will be reset to zeroes. That is not how an iterator is
expected to work.
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Unbinding an I/O subchannel with a child-CCW device in disconnected
state sometimes causes a kernel-panic. The race condition was seen
mostly during testing, when setting all the CHPIDs of a device to
offline and at the same time, the unbinding the I/O subchannel driver.
The kernel-panic occurs because of double delete, the I/O subchannel
driver calls device_del on the CCW device while another device_del
invocation for the same device is in-flight. For instance, disabling
all the CHPIDs will trigger the ccw_device_remove function, which will
call a ccw_device_unregister(), which ends up calling the device_del()
which is asynchronous via cdev's todo workqueue. And unbinding the I/O
subchannel driver calls io_subchannel_remove() function which calls the
ccw_device_unregister() and device_del().
This double delete can be prevented by serializing all CCW device
registration/unregistration calls into the driver core. This patch
introduces a mutex which will be used for this purpose.
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reported-by: Boris Fiuczynski <fiuczy@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
---[ Real Memory Copy Area Start ]---
0x001bfffffffff000-0x001c000000000000 4K PTE I
---[ Kasan Shadow Start ]---
---[ Real Memory Copy Area End ]---
0x001c000000000000-0x001c000200000000 8G PMD RW NX
...
---[ Kasan Shadow End ]---
ptdump does a stable sort of markers. Move kasan markers after
memcpy real to avoid swapping.
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
setup_vmem() already calls populate for all online memory regions.
pgtable_populate_end() could be removed.
Also rename pgtable_populate_begin() to pgtable_populate_init().
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Commit bb1520d581 ("s390/mm: start kernel with DAT enabled")
doesn't consider online memory holes due to potential memory offlining
and erroneously creates pgtables for stand-by memory, which bear RW+X
attribute and trigger a warning:
RANGE SIZE STATE REMOVABLE BLOCK
0x0000000000000000-0x0000000c3fffffff 49G online yes 0-48
0x0000000c40000000-0x0000000c7fffffff 1G offline 49
0x0000000c80000000-0x0000000fffffffff 14G online yes 50-63
0x0000001000000000-0x00000013ffffffff 16G offline 64-79
s390/mm: Found insecure W+X mapping at address 0xc40000000
WARNING: CPU: 14 PID: 1 at arch/s390/mm/dump_pagetables.c:142 note_page+0x2cc/0x2d8
Map only online memory ranges which fit within identity mapping limit.
Fixes: bb1520d581 ("s390/mm: start kernel with DAT enabled")
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
bpftrace and friends only consider functions present in
/sys/kernel/tracing/available_filter_functions.
For system calls there is the s390 specific problem that the system call
function itself is present via __se_sys##name() while the system call
itself is wired up via an __s390x_sys##name() alias. The required DWARF
debug information however is only available for the original function, not
the alias, but within available_filter_functions only the functions with
__s390x_ prefix are available. Which means the required DWARF debug
information cannot be found.
While this could be solved via tooling, it is easier to change the s390
specific system call wrapper handling.
Therefore get rid of this alias handling and implement system call wrappers
like most other architectures are doing. In result the implementation
generates the following functions:
long __s390x_sys##name(struct pt_regs *regs)
static inline long __se_sys##name(...)
static inline long __do_sys##name(...)
__s390x_sys##name() is the visible system call function which is also wired
up in the system call table. Its only parameter is a pt_regs variable.
This function calls the corresponding __se_sys##name() function, which has
as many parameters like the system call definition. This function in turn
performs all zero and sign extensions of all system call parameters, taken
from the pt_regs structure, and finally calls __do_sys##name().
__do_sys##name() is the actual inlined system call function implementation.
For all 64 bit system calls there is a 31/32 bit system call function
__s390_sys##name() generated, which handles all system call parameters
correctly as required by compat handling. This function may be wired
up within the compat system call table, unless there exists an
explicit compat system call function, which is then used instead.
Reported-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Move __S390_SYS_STUBx() the end of the CONFIG_COMPAT section, so both
variants (compat and non-compat) are close together and can be easily
compared.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Remove __SC_COMPAT_TYPE define which is an unused leftover.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
SYSCALL_METADATA() is only supposed to be used for non-compat system
calls. Otherwise there would be a name clash.
This also removes the inconsistency that s390 is the only architecture
which uses SYSCALL_METADATA() for compat system calls, and even that only
for compat system calls without parameters. Only two such compat system
calls exist.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
When debugging vmlinux with QEMU + GDB, the following GDB error may
occur:
(gdb) c
Continuing.
Warning:
Cannot insert breakpoint -1.
Cannot access memory at address 0xffffffffffff95c0
Command aborted.
(gdb)
The reason is that, when .interp section is present, GDB tries to
locate the file specified in it in memory and put a number of
breakpoints there (see enable_break() function in gdb/solib-svr4.c).
Sometimes GDB finds a bogus location that matches its heuristics,
fails to set a breakpoint and stops. This makes further debugging
impossible.
The .interp section contains misleading information anyway (vmlinux
does not need ld.so), so fix by discarding it.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Simplify the use of constants PMC_INIT and PMC_RELEASE.
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
With no in-kernel user, the source files can be merged.
Move all functions and the variable definitions to file perf_cpum_cf.c
This file now contains all the necessary functions and definitions
for the CPU Measurement counter facility device driver.
The files cpu_mcf.h and perf_cpum_cf_common.c are deleted.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Commit 17bebcc68e ("s390/cpum_cf: Add minimal in-kernel interface for
counter measurements") introduced a small in-kernel interface for CPU
Measurement counter facility.
There are no users of this interface, therefore remove it.
The following functions are removed:
kernel_cpumcf_alert(),
kernel_cpumcf_begin(),
kernel_cpumcf_end(),
kernel_cpumcf_avail()
there is no need for them anymore.
With the removal of function kernel_cpumcf_alert(), also remove
member alert in struct cpu_cf_events. Its purpose was to counter
measurement alert interrupts for the in-kernel interface.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Function stccm_avail() is defined in a header file and the
only user is one single source file. Move this function to the source
file where it is also used and remove it from the header file.
No functional change.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Function cpum_cf_ctrset_size() is defined in one source file and the
only user is in another source file. Move this function to the source
file where it is used and remove its prototype from the header file.
No functional change.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
To remove an event from the CPU Measurement counter facility
use the lock/unlock scheme as done in event creation. Remove
the atomic_add_unless function to make the code easier.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
That's an adaptation of commit f3a112c0c4 ("x86,rethook,kprobes:
Replace kretprobe with rethook on x86") to s390.
Replaces the kretprobe code with rethook on s390. With this patch,
kretprobe on s390 uses the rethook instead of kretprobe specific
trampoline code.
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The CPU Measurement Sampling Facility (CPUM_SF) installs large buffers
to save samples collected by hardware. These buffers are organized
as Sample Data Buffer Tables (SDBT) and Sample Data Buffers (SDB).
SDBs contain the samples which are extracted and saved in the perf
ring buffer.
The SDBTs are chained using real addresses and refer to SDBs using
real addresses.
The diagnostic sampling setup uses buffers provided by the process
which invokes perf_event_open system call. The buffers are memory
mapped. The buffers have been allocated by the kernel event
subsystem.
Add proper virtual to phyiscal address translation to the buffer
chaining. The current constraint which requires virtual equals
real address layout is removed.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Macro AUX_SDB_NUM() has three parameters. The first one is not used.
Remove the first parameter. Also convert the macros to inline functions.
No functional change.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The CPU Measurement Sampling Facility (CPUM_SF) installs large buffers
to save samples collected by hardware. These buffers are organized
as Sample Data Buffer Tables (SDBT) and Sample Data Buffers (SDB).
SDBs contain the samples which are extracted and saved in the perf
ring buffer.
The SDBTs are chained using real addresses and refer to SDBs using
real addresses.
Adds proper virtual to phyiscal address translation to the buffer
chaining. The current constraint which requires virtual equals real
address layout is removed.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Remove debug statements from function setup_pmc_cpu().
The debug statement displays a pointer value to a per cpu variable.
This pointer value is printed nowhere else, so it has no use for
cross reference.
No functional change.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Some inline helper functions are defined in a header file but used
in only one source file. Move these functions to the source file.
No functional change.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Swap is a function interface that provides exchange function. To avoid
code duplication, we can use swap function.
./arch/s390/mm/vmem.c:680:10-11: WARNING opportunity for swap().
[hca@linux.ibm.com: get rid of all temp variables]
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=3786
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230117060223.58583-1-jiapeng.chong@linux.alibaba.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
GCC 11.1.0 and 11.2.0 generate a wrong warning when compiling the
kernel e.g. with allmodconfig:
arch/s390/kernel/setup.c: In function ‘setup_lowcore_dat_on’:
./include/linux/fortify-string.h:57:33: error: ‘__builtin_memcpy’ reading 128 bytes from a region of size 0 [-Werror=stringop-overread]
...
arch/s390/kernel/setup.c:526:9: note: in expansion of macro ‘memcpy’
526 | memcpy(abs_lc->cregs_save_area, S390_lowcore.cregs_save_area,
| ^~~~~~
This could be addressed by using absolute_pointer() with the
S390_lowcore macro, but this is not a good idea since this generates
worse code for performance critical paths.
Therefore simply use a for loop to copy the array in question and get
rid of the warning.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Move __amode31_base declaration to proper header file to get rid of
arch/s390/boot/startup.c:24:15:
warning: symbol '__amode31_base' was not declared. Should it be static?
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Move Absolute Lowcore Area allocation to the decompressor.
As result, get_abs_lowcore() and put_abs_lowcore() access
brackets become really straight and do not require complex
execution context analysis and LAP and interrupts tackling.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Move Real Memory Copy Area allocation to the decompressor.
As result, memcpy_real() and memcpy_real_iter() movers
become usable since the very moment the kernel starts.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Currently the decompressor sets up only identity mapping.
Allow adding more address range types as a prerequisite
for allocation of kernel fixed mappings.
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The identity mapping is created in the decompressor,
there is no need to have the same functionality in
the kasan setup code. Thus, remove it.
Remove the 4KB pages check for first 1MB since there
is no need to take care of the lowcore pages.
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
As the kernel is executed in DAT-on mode only, remove
unnecessary DAT bit check together with the dead code.
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
