1, Better backtraces for humanization;
2, Relay BCE exceptions to userland as SIGSEGV;
3, Provide kernel fpu functions;
4, Optimize memory ops (memset/memcpy/memmove);
5, Optimize checksum and crc32(c) calculation;
6, Add ARCH_HAS_FORTIFY_SOURCE selection;
7, Add function error injection support;
8, Add ftrace with direct call support;
9, Add basic perf tools support.
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Merge tag 'loongarch-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch updates from Huacai Chen:
- Better backtraces for humanization
- Relay BCE exceptions to userland as SIGSEGV
- Provide kernel fpu functions
- Optimize memory ops (memset/memcpy/memmove)
- Optimize checksum and crc32(c) calculation
- Add ARCH_HAS_FORTIFY_SOURCE selection
- Add function error injection support
- Add ftrace with direct call support
- Add basic perf tools support
* tag 'loongarch-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (24 commits)
tools/perf: Add basic support for LoongArch
LoongArch: ftrace: Add direct call trampoline samples support
LoongArch: ftrace: Add direct call support
LoongArch: ftrace: Implement ftrace_find_callable_addr() to simplify code
LoongArch: ftrace: Fix build error if DYNAMIC_FTRACE_WITH_REGS is not set
LoongArch: ftrace: Abstract DYNAMIC_FTRACE_WITH_ARGS accesses
LoongArch: Add support for function error injection
LoongArch: Add ARCH_HAS_FORTIFY_SOURCE selection
LoongArch: crypto: Add crc32 and crc32c hw acceleration
LoongArch: Add checksum optimization for 64-bit system
LoongArch: Optimize memory ops (memset/memcpy/memmove)
LoongArch: Provide kernel fpu functions
LoongArch: Relay BCE exceptions to userland as SIGSEGV with si_code=SEGV_BNDERR
LoongArch: Tweak the BADV and CPUCFG.PRID lines in show_regs()
LoongArch: Humanize the ESTAT line when showing registers
LoongArch: Humanize the ECFG line when showing registers
LoongArch: Humanize the EUEN line when showing registers
LoongArch: Humanize the PRMD line when showing registers
LoongArch: Humanize the CRMD line when showing registers
LoongArch: Fix format of CSR lines during show_regs()
...
The ftrace samples need per-architecture trampoline implementations to
save and restore argument registers around the calls to my_direct_func*
and to restore polluted registers (e.g: ra).
Signed-off-by: Qing Zhang <zhangqing@loongson.cn>
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Now that the original _ftrace_direct APIs are gone, the "_multi"
suffixes only add confusion.
Link: https://lkml.kernel.org/r/20230321140424.345218-5-revest@chromium.org
Signed-off-by: Florent Revest <revest@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The _multi API requires that users keep their own ops but can enforce
that an op is only associated to one direct call.
Link: https://lkml.kernel.org/r/20230321140424.345218-3-revest@chromium.org
Signed-off-by: Florent Revest <revest@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
A common pattern when using the ftrace_direct_multi API is to unregister
the ops and also immediately free its filter. We've noticed it's very
easy for users to miss calling ftrace_free_filter().
This adds a "free_filters" argument to unregister_ftrace_direct_multi()
to both remind the user they should free filters and also to make their
life easier.
Link: https://lkml.kernel.org/r/20230321140424.345218-2-revest@chromium.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Florent Revest <revest@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
smatch reports this representative issue
samples/ftrace/ftrace-ops.c:15:14: warning: symbol 'nr_function_calls' was not declared. Should it be static?
The nr_functions_calls and several other global variables are only
used in ftrace-ops.c, so they should be static.
Remove the instances of initializing static int to 0.
Link: https://lore.kernel.org/linux-trace-kernel/20230130193708.1378108-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Calculating the average period requires a 64-bit division that leads
to a link failure on 32-bit architectures:
x86_64-linux-ld: samples/ftrace/ftrace-ops.o: in function `ftrace_ops_sample_init':
ftrace-ops.c:(.init.text+0x23b): undefined reference to `__udivdi3'
Use the div_u64() helper to do this instead. Since this is an init function that
is not called frequently, the runtime overhead is going to be acceptable.
Link: https://lore.kernel.org/linux-trace-kernel/20230130130246.247537-1-arnd@kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: b56c68f705 ("ftrace: Add sample with custom ops")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
When other architectures without the nospec functionality write their
direct-call functions of samples/ftrace/*.c, the including of
asm/nospec-branch.h must be taken care to fix the no header file found
error in building process.
This commit (ee3e2469b3 "x86/ftrace: Make it call depth tracking aware")
file-globally includes asm/nospec-branch.h providing CALL_DEPTH_ACCOUNT
for only x86 direct-call functions.
It seems better to move the including to `#ifdef CONFIG_X86_64`.
Link: https://lore.kernel.org/linux-trace-kernel/20230130085954.647845-1-suagrfillet@gmail.com
Signed-off-by: Song Shuai <suagrfillet@gmail.com>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Setting filters on an ftrace ops results in some memory being allocated
for the filter hashes, which must be freed before the ops can be freed.
This can be done by removing every individual element of the hash by
calling ftrace_set_filter_ip() or ftrace_set_filter_ips() with `remove`
set, but this is somewhat error prone as it's easy to forget to remove
an element.
Make it easier to clean this up by exporting ftrace_free_filter(), which
can be used to clean up all of the filter hashes after an ftrace_ops has
been unregistered.
Using this, fix the ftrace-direct* samples to free hashes prior to being
unloaded. All other code either removes individual filters explicitly or
is built-in and already calls ftrace_free_filter().
Link: https://lkml.kernel.org/r/20230103124912.2948963-3-mark.rutland@arm.com
Cc: stable@vger.kernel.org
Cc: Florent Revest <revest@chromium.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: e1067a07cf ("ftrace/samples: Add module to test multi direct modify interface")
Fixes: 5fae941b9a ("ftrace/samples: Add multi direct interface test module")
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Since ftrace has trampolines, don't use thunks for the __fentry__ site
but instead require that every function called from there includes
accounting. This very much includes all the direct-call functions.
Additionally, ftrace uses ROP tricks in two places:
- return_to_handler(), and
- ftrace_regs_caller() when pt_regs->orig_ax is set by a direct-call.
return_to_handler() already uses a retpoline to replace an
indirect-jump to defeat IBT, since this is a jump-type retpoline, make
sure there is no accounting done and ALTERNATIVE the RET into a ret.
ftrace_regs_caller() does much the same and gets the same treatment.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111148.927545073@infradead.org
misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
LIVEPATCH as the backtrace misses the function which is being fixed up.
- Add Straight Light Speculation mitigation support which uses a new
compiler switch -mharden-sls= which sticks an INT3 after a RET or an
indirect branch in order to block speculation after them. Reportedly,
CPUs do speculate behind such insns.
- The usual set of cleanups and improvements
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Merge tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core updates from Borislav Petkov:
- Get rid of all the .fixup sections because this generates
misleading/wrong stacktraces and confuse RELIABLE_STACKTRACE and
LIVEPATCH as the backtrace misses the function which is being fixed
up.
- Add Straight Line Speculation mitigation support which uses a new
compiler switch -mharden-sls= which sticks an INT3 after a RET or an
indirect branch in order to block speculation after them. Reportedly,
CPUs do speculate behind such insns.
- The usual set of cleanups and improvements
* tag 'x86_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
x86/entry_32: Fix segment exceptions
objtool: Remove .fixup handling
x86: Remove .fixup section
x86/word-at-a-time: Remove .fixup usage
x86/usercopy: Remove .fixup usage
x86/usercopy_32: Simplify __copy_user_intel_nocache()
x86/sgx: Remove .fixup usage
x86/checksum_32: Remove .fixup usage
x86/vmx: Remove .fixup usage
x86/kvm: Remove .fixup usage
x86/segment: Remove .fixup usage
x86/fpu: Remove .fixup usage
x86/xen: Remove .fixup usage
x86/uaccess: Remove .fixup usage
x86/futex: Remove .fixup usage
x86/msr: Remove .fixup usage
x86/extable: Extend extable functionality
x86/entry_32: Remove .fixup usage
x86/entry_64: Remove .fixup usage
x86/copy_mc_64: Remove .fixup usage
...
There's another compilation fail (first here [1]) reported by kernel
test robot for W=1 clang build:
>> samples/ftrace/ftrace-direct-multi-modify.c:7:6: warning: no previous
prototype for function 'my_direct_func1' [-Wmissing-prototypes]
void my_direct_func1(unsigned long ip)
Direct functions in ftrace direct sample modules need to have prototypes
defined. They are already global in order to be visible for the inline
assembly, so there's no problem.
The kernel test robot reported just error for ftrace-direct-multi-modify,
but I got same errors also for the rest of the modules touched by this patch.
[1] 67d4f6e3bf ftrace/samples: Add missing prototype for my_direct_func
Link: https://lkml.kernel.org/r/20211219135317.212430-1-jolsa@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Fixes: e1067a07cf ("ftrace/samples: Add module to test multi direct modify interface")
Fixes: ae0cc3b7e7 ("ftrace/samples: Add a sample module that implements modify_ftrace_direct()")
Fixes: 156473a0ff ("ftrace: Add another example of register_ftrace_direct() use case")
Fixes: b06457c83a ("ftrace: Add sample module that uses register_ftrace_direct()")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Adding ftrace-direct-multi-modify.ko kernel module that uses
modify_ftrace_direct_multi API. The core functionality is taken
from ftrace-direct-modify.ko kernel module and changed to fit
multi direct interface.
The init function creates kthread that periodically calls
modify_ftrace_direct_multi to change the trampoline address
for the direct ftrace_ops. The ftrace trace_pipe then shows
trace from both trampolines.
Link: https://lkml.kernel.org/r/20211206182032.87248-4-jolsa@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Tested-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Replace all ret/retq instructions with ASM_RET in preparation of
making it more than a single instruction.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134907.964635458@infradead.org
Currently it is not possible to build the ftrace direct multi example
anymore due to broken config dependencies. Fix this by adding
SAMPLE_FTRACE_DIRECT_MULTI config option.
This broke when merging s390-5.16-1 due to an incorrect merge conflict
resolution proposed by me.
Also rename SAMPLE_FTRACE_MULTI_DIRECT to SAMPLE_FTRACE_DIRECT_MULTI
so it matches the module name.
Fixes: 0b707e572a ("Merge tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux")
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20211115195614.3173346-2-hca@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
- Add support for ftrace with direct call and ftrace direct call samples.
- Add support for kernel command lines longer than current 896 bytes and
make its length configurable.
- Add support for BEAR enhancement facility to improve last breaking
event instruction tracking.
- Add kprobes sanity checks and testcases to prevent kprobe in the mid
of an instruction.
- Allow concurrent access to /dev/hwc for the CPUMF users.
- Various ftrace / jump label improvements.
- Convert unwinder tests to KUnit.
- Add s390_iommu_aperture kernel parameter to tweak the limits on
concurrently usable DMA mappings.
- Add ap.useirq AP module option which can be used to disable interrupt
use.
- Add add_disk() error handling support to block device drivers.
- Drop arch specific and use generic implementation of strlcpy and strrchr.
- Several __pa/__va usages fixes.
- Various cio, crypto, pci, kernel doc and other small fixes and
improvements all over the code.
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Merge tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:
- Add support for ftrace with direct call and ftrace direct call
samples.
- Add support for kernel command lines longer than current 896 bytes
and make its length configurable.
- Add support for BEAR enhancement facility to improve last breaking
event instruction tracking.
- Add kprobes sanity checks and testcases to prevent kprobe in the mid
of an instruction.
- Allow concurrent access to /dev/hwc for the CPUMF users.
- Various ftrace / jump label improvements.
- Convert unwinder tests to KUnit.
- Add s390_iommu_aperture kernel parameter to tweak the limits on
concurrently usable DMA mappings.
- Add ap.useirq AP module option which can be used to disable interrupt
use.
- Add add_disk() error handling support to block device drivers.
- Drop arch specific and use generic implementation of strlcpy and
strrchr.
- Several __pa/__va usages fixes.
- Various cio, crypto, pci, kernel doc and other small fixes and
improvements all over the code.
[ Merge fixup as per https://lore.kernel.org/all/YXAqZ%2FEszRisunQw@osiris/ ]
* tag 's390-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (63 commits)
s390: make command line configurable
s390: support command lines longer than 896 bytes
s390/kexec_file: move kernel image size check
s390/pci: add s390_iommu_aperture kernel parameter
s390/spinlock: remove incorrect kernel doc indicator
s390/string: use generic strlcpy
s390/string: use generic strrchr
s390/ap: function rework based on compiler warning
s390/cio: make ccw_device_dma_* more robust
s390/vfio-ap: s390/crypto: fix all kernel-doc warnings
s390/hmcdrv: fix kernel doc comments
s390/ap: new module option ap.useirq
s390/cpumf: Allow multiple processes to access /dev/hwc
s390/bitops: return true/false (not 1/0) from bool functions
s390: add support for BEAR enhancement facility
s390: introduce nospec_uses_trampoline()
s390: rename last_break to pgm_last_break
s390/ptrace: add last_break member to pt_regs
s390/sclp: sort out physical vs virtual pointers usage
s390/setup: convert start and end initrd pointers to virtual
...
There's compilation fail reported kernel test robot for W=1 build:
>> samples/ftrace/ftrace-direct-multi.c:8:6: warning: no previous
prototype for function 'my_direct_func' [-Wmissing-prototypes]
void my_direct_func(unsigned long ip)
The inlined assembly is used outside function, so we can't make
my_direct_func static and pass it as asm input argument.
However my_tramp is already extern so I think there's no problem
keeping my_direct_func extern as well and just add its prototype.
Link: https://lkml.kernel.org/r/20211101153907.377668-1-jolsa@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 5fae941b9a ("ftrace/samples: Add multi direct interface test module")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adding simple module that uses multi direct interface:
register_ftrace_direct_multi
unregister_ftrace_direct_multi
The init function registers trampoline for 2 functions,
and exit function unregisters them.
Link: https://lkml.kernel.org/r/20211008091336.33616-9-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add s390 support for ftrace direct call samples, which also enables
ftrace direct call selftests within ftrace selftests.
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20211012133802.2460757-5-hca@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
my_tramp[12]? are declared as global functions in C, but they are not
marked global in the inline assembly definition. This mismatch confuses
Clang's Control-Flow Integrity checking. Fix the definitions by adding
.globl.
Link: https://lkml.kernel.org/r/20201113183414.1446671-1-samitolvanen@google.com
Fixes: 9d907f1ae8 ("ftrace/samples: Add a sample module that implements modify_ftrace_direct()")
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a sample module that tests modify_ftrace_direct(), and this can be used
by the selftests as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add another module sample that registers a direct trampoline to a function
via register_ftrace_direct(). Having another module that does this allows to
test the use case of multiple direct callers registered, as more than one
direct caller goes into another path, and is needed to perform proper
testing of the register_ftrace_direct() call.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a sample module that shows a simple use case for
regsiter_ftrace_direct(), and how to use it.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Linus Torvalds