Due to kptr_restrict, JITted BPF code is now displayed like this:
000000000b6ed1b2: ebdff0800024 stmg %r13,%r15,128(%r15)
000000004cde2ba0: 41d0f040 la %r13,64(%r15)
00000000fbad41b0: a7fbffa0 aghi %r15,-96
Leaking kernel addresses to dmesg is not a concern in this case, because
this happens only when JIT debugging is explicitly activated, which only
root can do.
Use %px in this particular instance, and also to print an instruction
address in show_code and PCREL (e.g. brasl) arguments in print_insn.
While at present functionally equivalent to %016lx, %px is recommended
by Documentation/core-api/printk-formats.rst for such cases.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Sync with binutils and add a couple of missing instructions.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the arch/s390/kernel/ files with the correct SPDX license
identifier based on the license text in the file itself. The SPDX
identifier is a legally binding shorthand, which can be used instead of
the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
176.718956 Krnl Code: 00000000004d38b0: a54c0018 llihh %r4,24
176.718956 00000000004d38b4: b9080014 agr %r1,%r4
^
Using a tab to align disassembly lines which follow the first line with
"Krnl Code: " doesn't always work, e.g. if there is a prefix (timestamp
or syslog prefix) which is not 8 chars aligned. Go back to alignment
with spaces.
Fixes: b192571d1a ("s390/disassembler: increase show_code buffer size")
Signed-off-by: Vasily Gorbik <gor@linux.vnet.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>
The current way of adding new instructions to the opcode tables is
painful and error prone. Therefore add, similar to binutils, a text
file which contains all opcodes and the corresponding mnemonics and
instruction formats.
A small gen_opcode_table tool then generates a header file with the
required enums and opcode table initializers at the prepare step of
the kernel build.
This way only a simple text file has to be maintained, which can be
rather easily extended.
Unlike before where there were plenty of opcode tables and a large
switch statement to find the correct opcode table, there is now only
one opcode table left which contains all instructions. A second opcode
offset table now contains offsets within the opcode table to find
instructions which have the same opcode prefix. In order to save space
all 1-byte opcode instructions are grouped together at the end of the
opcode table. This is also quite similar to like it was before.
In addition also move and change code and definitions within the
disassembler. As a side effect this reduces the size required for the
code and opcode tables by ~1.5k.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
insn_to_mnemonic() was introduced ages ago for KVM debugging, but is
unused in the meantime. Therefore remove it.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
This instruction came with a z/VM extension and not with a specific
machine generation.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove a couple of instructions that are listed twice.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The e7 opcode table does not have an end marker. Hence when trying to
find an unknown e7 instruction the code will access memory behind the
table until it finds something that matches the opcode, or the kernel
crashes, whatever comes first.
This affects not only the in-kernel disassembler but also uprobes and
kprobes which refuse to set a probe on unknown instructions, and
therefore search the opcode tables to figure out if instructions are
known or not.
Cc: <stable@vger.kernel.org> # v3.18+
Fixes: 3585cb0280 ("s390/disassembler: add vector instructions")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Historically a lot of these existed because we did not have
a distinction between what was modular code and what was providing
support to modules via EXPORT_SYMBOL and friends. That changed
when we forked out support for the latter into the export.h file.
This means we should be able to reduce the usage of module.h
in code that is obj-y Makefile or bool Kconfig. The advantage
in doing so is that module.h itself sources about 15 other headers;
adding significantly to what we feed cpp, and it can obscure what
headers we are effectively using.
Since module.h was the source for init.h (for __init) and for
export.h (for EXPORT_SYMBOL) we consider each change instance
for the presence of either and replace as needed. Build testing
revealed some implicit header usage that was fixed up accordingly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The last in-kernel user is gone so we can finally remove this code.
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 double escape character sequence introduced with commit
272fa59ccb ("s390/dis: Fix handling of format specifiers") is not
necessary anymore since commit 561e103002 ("s390/dis: Fix printing
of the register numbers").
Instead this now generates an extra '%' character:
lg %%r1,160(%%r11)
So fix this and basically revert 272fa59ccb.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pull s390 updates from Martin Schwidefsky:
"Among the traditional bug fixes and cleanups are some improvements:
- A tool to generated the facility lists, generating the bit fields
by hand has been a source of bugs in the past
- The spinlock loop is reordered to avoid bursts of hypervisor calls
- Add support for the open-for-business interface to the service
element
- The get_cpu call is added to the vdso
- A set of tracepoints is defined for the common I/O layer
- The deprecated sclp_cpi module is removed
- Update default configuration"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits)
s390/sclp: fix possible control register corruption
s390: fix normalization bug in exception table sorting
s390/configs: update default configurations
s390/vdso: optimize getcpu system call
s390: drop smp_mb in vdso_init
s390: rename struct _lowcore to struct lowcore
s390/mem_detect: use unsigned longs
s390/ptrace: get rid of long longs in psw_bits
s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields
s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK
s390/Kconfig: remove pointless 64 bit dependencies
s390/dasd: fix failfast for disconnected devices
s390/con3270: testing return kzalloc retval
s390/hmcdrv: constify hmcdrv_ftp_ops structs
s390/cio: add NULL test
s390/cio: Change I/O instructions from inline to normal functions
s390/cio: Introduce common I/O layer tracepoints
s390/cio: Consolidate inline assemblies and related data definitions
s390/cio: Fix incorrect xsch opcode specification
s390/cio: Remove unused inline assemblies
...
The print_insn() function returns strings like "lghi %r1,0". To escape the
'%' character in sprintf() a second '%' is used. For example "lghi %%r1,0"
is converted into "lghi %r1,0".
After print_insn() the output string is passed to printk(). Because format
specifiers like "%r" or "%f" are ignored by printk() this works by chance
most of the time. But for instructions with control registers like
"lctl %c6,%c6,780" this fails because printk() interprets "%c" as
character format specifier.
Fix this problem and escape the '%' characters twice.
For example "lctl %%%%c6,%%%%c6,780" is then converted by sprintf()
into "lctl %%c6,%%c6,780" and by printk() into "lctl %c6,%c6,780".
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since commit b006f19b05 ("lib/vsprintf.c: handle invalid format
specifiers more robustly") I get errors like
[...]
Krnl Code: 00000000004e2410: c00400000000 brcl 0,4e2410
Please remove unsupported %r in format string
[ 8.179483] ------------[ cut here ]------------
[ 8.179484] WARNING: at lib/vsprintf.c:1781
Turns out that our disassembler relied on %r not being used as format
string. Let's do the proper escaping of our decode buffers.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.
The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e58 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.
Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The multi-threading facility is introduced with the z13 processor family.
This patch adds code to detect the multi-threading facility. With the
facility enabled each core will surface multiple hardware threads to the
system. Each hardware threads looks like a normal CPU to the operating
system with all its registers and properties.
The SCLP interface reports the SMT topology indirectly via the maximum
thread id. Each reported CPU in the result of a read-scp-information
is a core representing a number of hardware threads.
To reflect the reduced CPU capacity if two hardware threads run on a
single core the MT utilization counter set is used to normalize the
raw cputime obtained by the CPU timer deltas. This scaled cputime is
reported via the taskstats interface. The normal /proc/stat numbers
are based on the raw cputime and are not affected by the normalization.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since we have an in-kernel disassembler we can make sure that
there won't be any kprobes set on random data.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The patch moves some of the definitions to a
header file. No functional changes involved.
I have retained the Copyright Statement from the
original file.
Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
[Heiko Carstens: rename s390-dis.h to dis.h]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Rename 'insn' and 'operand' structures to more canonical names
to avoid conflicts.
struct insn represents information about an instruction, including
the mnemonics, format and opcode.
struct operand represents the 'properties' and information on howto
interpret the operand value and doesn't contain the value.
We rename these structures for avoiding a global conflict.
i.e,
1,$s/struct insn/struct s390_insn/g
1,$s/struct operand/struct s390_operand/g
Signed-off-by: Suzuki K Poulose <suzuki@in.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If the size of the opcode to be printed is larger than "len" we'll
see an overflow of an unsigned long value, which means that the
while loop within print_fn_code() will loop quite a long time until
there is the next chance for an exit.
So add an early exit check.
Reported-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Pass buffer length in extra parameter.
Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
We are using sizeof operator for an array given as function argument,
which is incorrect.
Signed-off-by: Syam Sidhardhan <s.syam@samsung.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The set-program-parameter (SPP) instruction has been renamed to
load-program-parameter (LPP) (see SA23-2260). Reflect this change
and rename all macro/instruction references.
Also remove the duplicate SPP/LPP entry in the kernel disassembler
instruction list.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Add PCI support for s390, (only 64 bit mode is supported by hardware):
- PCI facility tests
- PCI instructions: pcilg, pcistg, pcistb, stpcifc, mpcifc, rpcit
- map readb/w/l/q and writeb/w/l/q to pcilg and pcistg instructions
- pci_iomap implementation
- memcpy_fromio/toio
- pci_root_ops using special pcilg/pcistg
- device, bus and domain allocation
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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Merge tag 'kvm-3.7-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Avi Kivity:
"Highlights of the changes for this release include support for vfio
level triggered interrupts, improved big real mode support on older
Intels, a streamlines guest page table walker, guest APIC speedups,
PIO optimizations, better overcommit handling, and read-only memory."
* tag 'kvm-3.7-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (138 commits)
KVM: s390: Fix vcpu_load handling in interrupt code
KVM: x86: Fix guest debug across vcpu INIT reset
KVM: Add resampling irqfds for level triggered interrupts
KVM: optimize apic interrupt delivery
KVM: MMU: Eliminate pointless temporary 'ac'
KVM: MMU: Avoid access/dirty update loop if all is well
KVM: MMU: Eliminate eperm temporary
KVM: MMU: Optimize is_last_gpte()
KVM: MMU: Simplify walk_addr_generic() loop
KVM: MMU: Optimize pte permission checks
KVM: MMU: Update accessed and dirty bits after guest pagetable walk
KVM: MMU: Move gpte_access() out of paging_tmpl.h
KVM: MMU: Optimize gpte_access() slightly
KVM: MMU: Push clean gpte write protection out of gpte_access()
KVM: clarify kvmclock documentation
KVM: make processes waiting on vcpu mutex killable
KVM: SVM: Make use of asm.h
KVM: VMX: Make use of asm.h
KVM: VMX: Make lto-friendly
KVM: x86: lapic: Clean up find_highest_vector() and count_vectors()
...
Conflicts:
arch/s390/include/asm/processor.h
arch/x86/kvm/i8259.c
Allow user-space processes to use transactional execution (TX).
If the TX facility is available user space programs can use
transactions for fine-grained serialization based on the data
objects that are referenced during a transaction. This is
useful for lockless data structures and speculative compiler
optimizations.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Allow user-space threads to use runtime instrumentation (RI). To enable RI
for a thread there is a new s390 specific system call, sys_s390_runtime_instr,
that takes as parameter a realtime signal number. If the RI facility is
available the system call sets up a control block for the calling thread with
the appropriate permissions for the thread to modify the control block.
The user-space thread can then use the store and modify RI instructions to
alter the control block and start/stop the instrumentation via RION/RIOFF.
If the user specified program buffer runs full RI triggers an external
interrupt. The external interrupt is translated to a real-time signal that
is delivered to the thread that enabled RI on that CPU. The number of
the real-time signal is the number specified in the RI system call. So,
user-space can select any available real-time signal number in case the
application itself uses real-time signals for other purposes.
The kernel saves the RI control blocks on task switch only if the running
thread was enabled for RI. Therefore, the performance impact on task switch
should be negligible if RI is not used.
RI is only enabled for user-space mode and is disabled for the supervisor
state.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The s390 implementation of the JIT compiler for packet filter speedup.
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
- bring back critical fixes (esp. aa67f6096c)
- provide an updated base for development
* upstream: (4334 commits)
missed mnt_drop_write() in do_dentry_open()
UBIFS: nuke pdflush from comments
gfs2: nuke pdflush from comments
drbd: nuke pdflush from comments
nilfs2: nuke write_super from comments
hfs: nuke write_super from comments
vfs: nuke pdflush from comments
jbd/jbd2: nuke write_super from comments
btrfs: nuke pdflush from comments
btrfs: nuke write_super from comments
ext4: nuke pdflush from comments
ext4: nuke write_super from comments
ext3: nuke write_super from comments
Documentation: fix the VM knobs descritpion WRT pdflush
Documentation: get rid of write_super
vfs: kill write_super and sync_supers
ACPI processor: Fix tick_broadcast_mask online/offline regression
ACPI: Only count valid srat memory structures
ACPI: Untangle a return statement for better readability
Linux 3.6-rc1
...
Signed-off-by: Avi Kivity <avi@redhat.com>
We use the user_mode() helper already at several places but also
have the open coded variant at other places.
Convert the code to always use the helper function.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Provide a new function, insn_to_mnemonic, by which e.g. kvm can obtain
a human-readable decoding of an instruction's opcode.
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.
Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
If an exception happens the PSW either points to the instruction that
caused the exception or to the instruction that follows the exception
causing instruction, depending on the exception type.
Since the inkernel disassembler adds a ">" in front of the disassembly
many people assume incorrectly that the instruction that is pointed to
must be the cause of the exception. To make people aware that this is
not necessarily the case add a different character in front of the
disassembled instruction that precedes the current instructions.
The output now looks like this:
Krnl PSW : 0704200180000000 0000000000120de8 (test_function+0x0/0x100)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:0 CC:2 PM:0 EA:3
Krnl GPRS: 000003ff00000000 0000000000120de4 000000000091bb40 0000000000000001
000003fffd2ea000 0000000030fb7df8 0000000030fb7f10 000003ffffa113c8
000000000091bb40 000003fffd2ea000 0000000000000002 0000000030fb7f10
000000003f290240 0000000000606220 00000000002cfb5c 0000000030fb7d58
Krnl Code: 0000000000120ddc: b90400a9 lgr %r10,%r9
0000000000120de0: a7f4ff88 brc 15,120cf0
#0000000000120de4: a7f40001 brc 15,120de6
>0000000000120de8: a7f13f80 tmll %r15,16256
0000000000120dec: eb8ff0580024 stmg %r8,%r15,88(%r15)
0000000000120df2: a7840001 brc 8,120df4
0000000000120df6: b90400ef lgr %r14,%r15
0000000000120dfa: a7fbffb8 aghi %r15,-72
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
