The libdw callback API has two levels: dwfl_getthread_frames() first finds
the requested thread using the next_thread() or get_thread() callback and
then walks its stack.
Since perf only has a snapshot of the stack of a single thread, it
provides a stubbed-out API that always returns the pid the Dwfl was
attached with (i.e. whatever was passed to dwfl_attach_state()), rather
than the actual sampled thread's TID.
Commit 6b2658b3f3 ("perf unwind-libdw: Don't discard loaded ELF/DWARF
after every unwind") changed libdw unwinding from recreating the Dwfl
object for each sample to caching it in struct maps, which is shared by
every thread in the process. It left next_thread() unchanged.
Since the pid passed to dwfl_attach_state() is only set at creation, only
the thread of the first sample is ever found. As a result,
dwfl_getthread_frames() fails with ESRCH when asked to unwind a sample
from another thread.
Make next_thread() return the current sample's TID, provide get_thread()
so libdw can find it directly, and pass the process PID expected by
dwfl_attach_state(). This allows libdw to unwind samples from every thread
in a multi-threaded process.
Add a shell regression test that records a four-thread workload and
verifies that libdw recovers the worker callchain for every worker TID.
Fixes: 6b2658b3f3 ("perf unwind-libdw: Don't discard loaded ELF/DWARF after every unwind")
Assisted-by: Codex:gpt-5.6-sol
Signed-off-by: Alessio Podda <aleph.pi.gh@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
perf tools fixes for v7.2.
- Update header copies of kernel headers, including const.h, fs.h,
perf_event.h, gfp_types.h, kvm.h, cpufeatures.h, rtnetlink.hp,
msr-index.h, drm.h and socket.h.
- Add some build files related to BPF skels to .gitignore.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
struct popup_action has a thread but this is duplicated in the
map_symbol. Remove the non-map_symbol version so that there's only ever
1 thread with a popup_action.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
If a thread isn't given to map_symbol__get_arch(), try harder to determine
the arch for disassembly. Do this by utilizing fallback paths such as
reading the e_machine from a map's DSO ELF header for user-space libraries.
Additionally, rely on map__kmaps() and maps__machine() to reliably extract
the recorded machine environment and e_machine for kernel and kallsyms maps,
perfectly preventing silent, incorrect host fallbacks to uname() during
cross-platform Capstone annotation sessions.
At the same time, ensure all remaining uses of a map_symbol's thread pointer
do not assume it is non-NULL to eliminate UI segmentation faults, and remove
the fragile, redundant thread__get_arch() function to streamline the
annotate and disassembly subsystem architecture.
Fixes: 0e26ba5a87 ("perf disasm: Refactor arch__find and initialization of arch structs")
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In hists_browser__zoom_map(), the active dso is assigned as a raw
pointer to hists->dso_filter without acquiring a reference using
dso__get(). This creates a potential use-after-free defect if the
underlying dso is released while the filter remains active.
Fix it by properly acquiring a reference via dso__get() when assigning
the filter, and releasing it with dso__put() when clearing it.
Additionally, since the browser stack relies on pstack__new() and deletes
it completely upon exiting, we must fully reset the persistent hists
structure by un-eliding columns and recalculating histogram filter
states for dso, thread, and symbols upon exit to guarantee immaculate,
uncorrupted state across browser tab switching.
Closes: https://lore.kernel.org/linux-perf-users/20260709170834.52F1A1F000E9@smtp.kernel.org/
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Populates the map_symbol thread in the UI code to fix the e_machine
lookup for cross-platform disassembly when using the annotate action.
At the same time, refactor the UI options and actions generation to
comply with the perf subsystem's strict reference counting abstraction
requirements for 'struct map_symbol' and 'struct thread'. Introduce
explicit reference acquiring via map_symbol__copy() and thread__get() for
menu items, safely clean them up between menu iterations using a new
free_popup_actions() helper, and utilize insulated temporary action
variables for direct hotkey handler execution.
Fixes: 0e26ba5a87 ("perf disasm: Refactor arch__find and initialization of arch structs")
Reported-by: Josh Stone <jistone@redhat.com>
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In add_script_opt(), when the browser selection has no valid hist_entry
(for example, when all entries are filtered out or the trace is empty),
hist_browser__selected_entry() returns NULL.
Add an explicit check for he == NULL prior to accessing he->time to avoid a
potential NULL pointer dereference crash.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
In evsel__hists_browse(), the local stack array 'buf' is assigned
directly to the persistent 'hists->symbol_filter_str' pointer. When the
browser returns or is exited, this dangling pointer remains active in
the 'hists' struct and is read asynchronously by the perf top background
timer, triggering a stack use-after-return.
Fix it by properly duplicating the input string using strdup(), safely
invoking zfree() to prevent memory leaks when overwriting, and cleanly
resetting and freeing the symbol filter string upon exiting the browser.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Try to remove some, but not all duplicate toolchain definitions. In
these instances, their makefiles already include
tools/scripts/Makefile.include which defines these in a consistent way.
STRIP is the only one that was set with an '=', but I don't think it
was significant so that difference can be dropped.
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Documentation/kbuild/llvm.rst mentions that readelf is included in the
LLVM toolchain, but it's not currently included in this block.
Add it so that LLVM=... options also apply to readelf. Users in tools/
were Perf which was hardcoding it, and another was the BPF makefile.
Both already include Makefile.include so convert them to use the new
variables.
Where readelf wasn't doing anything arch specific, use HOSTREADELF
because it's more likely to be installed.
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: James Clark <james.clark@linaro.org>
Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
These blocks are quite big and unreadable without indentation. Indent
them.
No functional changes intended.
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
The version of LLVM tools can be given on the build command with
LLVM=-15, but this isn't applied to all tools. For example $(CC) gets
versioned, but $(CLANG) doesn't. This causes a Perf build with LTO=1 to
fail with an error about mixed clang versions:
ld.lld: error: libperf/core.o: Unknown attribute kind (86)
(Producer: 'LLVM18.1.8' Reader: 'LLVM 15.0.7')
This file has two "ifneq ($(LLVM),)" blocks adjacent to each other, so
merge these blocks making it obvious that all tools should be versioned
consistently and there is nothing special about each block.
This also reveals that ?= and "allow-override" are used inconsistently
between the blocks. "allow-override" is technically only required for
builtin variables, but isn't only used on them, and doesn't do any harm
if used on a non-builtin. Make them all "allow-override" for
consistency. The only functional difference this will cause is if there
is a file level definition of one of the variables followed by an
"#include of Makefile.include" which will now overwrite. But this isn't
done and in a later commit some of the duplicate definitions will be
removed for good measure.
There are also some other LLVM tools that are not defined here and will
be moved in a later commit.
Signed-off-by: James Clark <james.clark@linaro.org>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Fixes: e9c281928c ("kbuild: Make $(LLVM) more flexible")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Provide a helper function trace__field_is_ip() in
trace__fprintf_tp_fields() to ensure that tracepoint fields representing
instruction pointers such as "__probe_ip", "caller_ip", and
"call_site" are always formatted as hexadecimal memory addresses rather
than signed integers.
For example, when running a kmem:kfree tracepoint:
# perf trace --show-cpu --event kmem:kfree --max-event 1
Before this change, "call_site" was represented as a signed integer:
0.000 [003] xfce4-terminal/2201 kmem:kfree(call_site: -1714572588, ptr: 0xffff8afee0303000)
After this change, "call_site" is correctly represented in hexadecimal:
0.000 [003] xfce4-terminal/2201 kmem:kfree(call_site: 0xffffffff99cf1194, ptr: 0xffff8afee0303000)
This improves the readability of perf trace output by making code
addresses straightforward to parse and map to kernel symbols.
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Currently, dynamic non-array fields such as 'cpumask_t' are mishandled in
'perf trace', causing the raw length and offset descriptors to be interpreted
and displayed as a literal integer (e.g., "cpumask: 524320" instead of the
actual mask data).
Correct the parsing of dynamic fields that do not have the
TEP_FIELD_IS_ARRAY flag set by introducing helper functions
format_field__get_raw_data() and format_field__get_cpumask().
Using these helpers, resolve the pointer to the raw bits within the
payload and format the cpumask as a zero-padded hexadecimal string by default.
Fixes: c5e006cdbd ("perf trace: Support tracepoint dynamic char arrays")
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Currently, jevents.py parses hundreds of JSON event and metric files
sequentially across all CPU architectures during Kbuild startup,
taking ~3.5 seconds of single-core execution time.
Refactor jevents.py to pre-populate its internal JSON AST cache in
parallel across all available CPU cores using
ProcessPoolExecutor. First gather all the paths with ftw and
collect_json, then spawn _parallel_read_json_events that starts
workers to just read the json events. Define the worker process
initializer _init_worker so that _arch_std_events is available under
spawn multiprocessing semantics.
This accelerates the JSON parsing phase by over 10x (from ~3.0s down
to ~290ms), reducing overall jevents.py execution time by 3.5x (from
~3.56s down to ~1.03s).
Tested-by: James Clark <james.clark@linaro.org>
Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Clean up and restructure the python setup script to resolve pylint
warnings, improve code quality, and increase robustness and
readability, targeting Python 3.9+ (the Linux kernel build minimum
Python version).
Changes:
- Restructure the script to use a `main()` function as the entry point,
leaving only imports, classes, and pure functions at module level.
- Eliminate all global/module-level variables, making them local to
`main()` or the respective classes/functions.
- Make `clang_has_option` a pure function by passing all necessary
parameters explicitly.
- Extract clang compiler flag filtering into a new
`filter_clang_options` helper function. This function uses a loop
over a tuple of options, replacing ~30 lines of repetitive blocks
and reducing branch/statement complexity in the main flow.
- Cleanly define attributes in `__init__` for `BuildExt` and
`InstallLib` and read environment variables dynamically within the
methods (including `srctree` in `InstallLib.run`), removing their
dependency on global variables.
- Replace legacy Popen with subprocess.run for safer process handling.
- Use quote-aware flag filtering (`shlex.split`, filter, `shlex.join`)
on sysconfig CFLAGS and OPT instead of regex `re.sub` substitutions.
This avoids boundary bugs and safely handles quoted arguments and
options with values.
- Rely on setuptools to handle user CFLAGS from the environment
directly rather than manually prepending them to extra_compile_args.
- Safely parse `CC` env var using `shlex.split` to handle quotes and
pass compiler arguments as `list[str]` lists to helper functions,
avoiding redundant string formatting and parsing.
- Remove unused `import re`.
- Rename setuptools command subclasses to PascalCase (BuildExt,
InstallLib).
- Add type annotations to functions and methods.
- Add missing docstrings for module, functions, and classes.
- Split long lines to adhere to standard limits.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Refactor perf_cap__capable() to completely remove the used_root out-parameter
as requested by the maintainer. Relying on an explicit used_root boolean
poisoned sequential capability checks (e.g. failing CAP_SYS_ADMIN checks
poisoning the flag for subsequent CAP_PERFMON evaluations for unprivileged
users) and created redundant complexity across check_ftrace_capable(),
symbol__read_kptr_restrict(), and perf_event_paranoid_check().
Streamline the capability API to perform a pure true/false boolean
evaluation. The function checks the Effective set using SYS_capget; if
the syscall is missing or fails on legacy kernels, it cleanly falls back
to checking EUID == 0. This perfectly preserves modern capability-aware host
sessions, guarantees transparent fallback for older kernels, and correctly
rejects privileged operations for containerized root processes that have
explicitly dropped their capability bounding and permitted sets.
Fixes: e25ebda78e ("perf cap: Tidy up and improve capability testing")
Suggested-by: Namhyung Kim <namhyung@kernel.org>
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
cs_etm__get_trace() returns an int, but it used to return etmq->buf_len
on success. That value comes from auxtrace_buffer::size, which is a
size_t. For a large AUX trace block, returning the byte count through an
int can overflow and make a valid buffer look like a negative error.
The callers do not need the actual byte count from cs_etm__get_trace().
The buffer length is already stored in the etmq->buf_len. The callers
only need to distinguish three states:
< 0: error
= 0: no more AUX buffers
> 0: data is available
Make cs_etm__get_trace() return 0 for all non-error cases and use
etmq->buf_len to indicate whether a new buffer was found. Then make
cs_etm__get_data_block() return 1 whenever data is available, instead of
returning the buffer length.
Also refactor cs_etm__get_data_block() to make its return value
semantics clearer.
Reported-by: Suyash Mahar <smahar@meta.com>
Fixes: 8224531cf5 ("perf cs-etm: Modularize auxtrace_buffer fetch function")
Signed-off-by: Leo Yan <leo.yan@arm.com>
Reviewed-by: James Clark <james.clark@linaro.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
To pick up the changes in:
103ff3a50e ("KVM: s390: Add capability to support 2G hugepages")
229132c309 ("LoongArch: KVM: Add DMSINTC device support")
2619da73bb ("KVM: x86: Use __DECLARE_FLEX_ARRAY() for UAPI structures with VLAs")
4aebd7d5c7 ("KVM: s390: Add KVM capability for ESA mode guests")
4f256d5770 ("KVM: x86: nSVM: Save/restore gPAT with KVM_{GET,SET}_NESTED_STATE")
822790ab01 ("KVM: x86: Define KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT")
8800dbf661 ("KVM: arm64: Allow userspace to create protected VMs when pKVM is enabled")
bf8f3cec93 ("KVM: s390: vsie: Refactor handle_stfle")
c547c51ff4 ("KVM: arm64: gic-v5: Add ARM_VGIC_V5 device to KVM headers")
d7507a94a0 ("KVM: SVM: Treat exit_code as an unsigned 64-bit value through all of KVM")
This addresses these perf build warnings:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h
diff -u tools/arch/s390/include/uapi/asm/kvm.h arch/s390/include/uapi/asm/kvm.h
Please see tools/include/uapi/README for further details.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
45e57cfb7b ("fs: Clarify FS_CASEFOLD_FL semantics in UAPI header")
That don't result in changes to the string tables generated from this header.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/perf/trace/beauty/include/uapi/linux/fs.h include/uapi/linux/fs.h
Please see tools/include/uapi/README for further details.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
4987a5763f ("net: block MSG_NO_SHARED_FRAGS in sendmsg()")
That don't result in changes to the string tables generated from this header.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/perf/trace/beauty/include/linux/socket.h include/linux/socket.h
Please see tools/include/uapi/README for further details.
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
a1b6cf8e5e ("drm: uapi: Use SPDX in DRM core uAPI headers")
dc2d30e7db ("drm/doc: document DRM_IOCTL_SYNCOBJ_EVENTFD")
That don't result in changes to the string tables generated from this header.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/perf/trace/beauty/include/uapi/drm/drm.h include/uapi/drm/drm.h
Please see tools/include/uapi/README for further details.
Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Cc: Simon Ser <contact@emersion.fr>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
5ce9cc5a23 ("coco/tdx-host: Don't expose P-SEAMLDR information on CPUs with erratum")
7658b9343a ("KVM: SVM: add GMET bit definitions")
de0bfdc713 ("KVM: x86: Advertise AVX512 Bit Matrix Multiply (BMM) to userspace")
That just rebuilds perf, silencing this build warning.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
Please see tools/include/uapi/README for further details.
Cc: Chao Gao <chao.gao@intel.com>
Cc: Nikunj A Dadhania <nikunj@amd.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
b56ca146a2 ("vmalloc: add __GFP_SKIP_KASAN support")
6a288a4ddb ("mm/page_alloc: fix initialization of tags of the huge zero folio with init_on_free")
That just rebuilds perf, silencing this build warning.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/linux/gfp_types.h include/linux/gfp_types.h
Please see tools/include/uapi/README for further details.
Cc: David Hildenbrand (Arm) <david@kernel.org>
Cc: Muhammad Usama Anjum <usama.anjum@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
b588019e85 ("rtnetlink: add RTEXT_FILTER_NAME_ONLY support")
That just rebuilds perf, silencing this build warning.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/rtnetlink.h include/uapi/linux/rtnetlink.h
Please see tools/include/uapi/README for further details.
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
de9e2b3d88 ("uapi: Provide DIV_ROUND_CLOSEST()")
That just rebuilds perf, silencing this build warning.
This addresses this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/const.h include/uapi/linux/const.h
Please see tools/include/uapi/README for further details.
Cc: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
In 713eeb2279 ("perf build: Move BPF skeleton generation out of
Makefile.perf") the bpf_skel used with 'perf bench uprobe' was moved
from tools/perf/util/bpf_skel/ to tools/perf/bench/bpf_skel.
Copy tools/perf/util/bpf_skel/.gitignore to that new directory so that
files generated during build get ignored by git.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 713eeb2279 ("perf build: Move BPF skeleton generation out of Makefile.perf")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull kvm fixes from Paolo Bonzini:
"RISC-V:
- Avoid redundant allocations when allocating IMSIC page tables
- Apply SBI FWFT LOCK flag only on successful set
- Bound SBI PMU counter mask scan to BITS_PER_LONG, since on RV32 the
PMU SBI start/stop helper can only access 32 PMU counters.
- Skip TLB flush when G-stage PTE becomes valid if the Svvptc
extension is available.
- Always show Zicbo[m|z|p] block sizes in ONE_REG
- Inject instruction access fault on unmapped guest fetch
- Use raw spinlock for irqs_pending and irqs_pending_mask
- Fix Spectre-v1 in vector register access via ONE_REG
x86:
- Fixes to SEV selftests
- Once free_nested() did a VMCLEAR of shadow VMCS, there's no need to
VMCLEAR it again if the kernel is preempted and thread migration
happens
- Preserve nested TDP shadow page tables if they are used as roots,
instead of clearing them unnecessarily
- Fix use of stale data if out-of-memory happens after vendor module
reload
- Check for invalid/obsolete root *after* making MMU pages available,
because the latter can make a page invalid
- Only reset TSC Deadline Timer in apic_timer_expired on KVM_RUN"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: Only reset TSC Deadline Timer in apic_timer_expired on KVM_RUN
KVM: selftests: sev_init2_tests: Derive SEV availability from KVM
KVM: selftests: sev_smoke_test: Only run VM types the host offers
KVM: x86/mmu: Fix use-after-free on vendor module reload
KVM: x86/mmu: Preserve nested TDP shadow page tables if they are used as roots
KVM: x86: Check for invalid/obsolete root *after* making MMU pages available
KVM: nVMX: Hide shadow VMCS right after VMCLEAR
KVM: riscv: Fix Spectre-v1 in vector register access
RISC-V: KVM: Serialize virtual interrupt pending state updates
RISC-V: KVM: Inject instruction access fault on unmapped guest fetch
RISC-V: KVM: Zicbo[m|z|p] block sizes should be always present in ONE_REG
riscv: kvm: Skip TLB flush when G-stage PTE becomes valid with Svvptc
KVM: riscv: PMU: Bound counter mask scan to BITS_PER_LONG
KVM: riscv: SBI FWFT: Apply LOCK flag only on successful set
RISC-V: KVM: Avoid redundant page-table allocations in ioremap topup
Pull probes fixes from Masami Hiramatsu:
- Avoid temporary buffer truncation in match_command_args()
Compare argument name, delimiter, and comm expression directly
instead of formatting into a stack buffer to prevent false
matching failures
- Prevent out-of-bounds write in __trace_probe_log_err()
Return early when trace_probe_log.argc is zero to prevent
out-of-bounds access when constructing the formatted error
command string
- Fix potential underflow in LEN_OR_ZERO macro
Ensure buffer length is greater than current position before
subtraction to prevent unsigned size underflow when formatting
print strings
- Fix exact system name matching in eprobe_dyn_event_match()
Check system name null-termination to avoid partial prefix
matching when comparing event probe target system names
* tag 'probes-fixes-v7.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing/eprobe: Fix exact system name matching in eprobe_dyn_event_match()
tracing/probes: Fix potential underflow in LEN_OR_ZERO macro
tracing/probes: Prevent out-of-bounds write in __trace_probe_log_err()
tracing/probes: Avoid temporary buffer truncation in trace_probe_match_command_args()
Pull btrfs fixes from David Sterba:
"I'm catching up with the fix backlog in the development branch, so
here's a number of them and will probably send one more for this or
the next rc:
- relocation fixes:
- skip attempting compression on reloc inodes
- exclude inline extents from file extent offset checks
- fix minor memory leak after error when adding reloc root
- fix root cleanup after inserting and merging
- fix clearing folio tags after writeback
- clear logging flag of extent map before splitting
- fix unsigned 32/64 type conversions when accounting dirty metadata,
leading to continually exceeding threshold
- fix regression in 32bit compat ioctl for subvolume info
- fix type of SEARCH_TREE ioctl buffer in UAPI header
- fix expression in ASSERT expression which can be unconditionally
evaluated on some compilers
- only account delalloc bytes for regular inodes"
* tag 'for-7.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix GET_SUBVOL_INFO after compat refactor
btrfs: free mapping node on duplicate reloc root insert
btrfs: fix a regression where PAGECACHE_TAG_DIRTY is never cleared
btrfs: don't propagate EXTENT_FLAG_LOGGING to split extent maps
btrfs: fix u32 to s64 type conversion in dirty_metadata_bytes accounting
btrfs: fix NULL pointer deref during assertion in btrfs_backref_free_node()
btrfs: only account delalloc bytes for regular file inodes in btrfs_getattr()
btrfs: reject inline file extents item in get_new_location()
btrfs: do not try compression for data reloc inodes
btrfs: declare btrfs_ioctl_search_args_v2::buf as __u8
btrfs: fix reloc root cleanup in merge_reloc_roots()
btrfs: fix use-after-free on reloc root after error in insert_dirty_subvol()
KVM/riscv fixes for 7.2, take #1
- Avoid redundant page-table allocations in ioremap pcache topup
- Apply SBI FWFT LOCK flag only on successful set
- Bound SBI PMU counter mask scan to BITS_PER_LONG
- Skip TLB flush when G-stage PTE becomes valid with Svvptc
- Zicbo[m|z|p] block sizes should be always present in ONE_REG
- Inject instruction access fault on unmapped guest fetch
- Serialize virtual interrupt pending state updates using raw spinlock
- Fix Spectre-v1 in vector register access via ONE_REG
On Intel platforms with a VMX preemption timer and APICv, if a VMM
calls KVM_GET_LAPIC before KVM_GET_MSRS to save the vCPU state, it is
possible to lose a pending timer interrupt.
If the thread running these ioctls is migrated to another core after
calling KVM_GET_LAPIC but before KVM_GET_MSRS and the guest is using
their LAPIC timer in TSC-deadline mode, not only does the save LAPIC
state not carry the pending interrupt, the TSCDEADLINE MSR will be
zeroed.
After migration across CPUs, KVM_GET_MSRS calls vcpu_load, posting the
interrupt and clearing the MSR:
vcpu_load() ->
kvm_arch_vcpu_load() ->
kvm_lapic_restart_hv_timer() ->
start_hv_timer() ->
apic_timer_expired() ->
kvm_apic_inject_pending_timer_irqs()
. post interrupt into the LAPIC state
. clear IA32_TSCDEADLINE
The saved LAPIC state will be missing the pending interrupt and the saved
MSR will be zero. Oops.
Fix by only posting an interrupt when we're attempting to enter the guest
(vcpu->wants_to_run == true), not for vcpu_load from other paths.
Assisted-by: gemini:gemini-3.1-pro-preview
Debugged-by: David Matlack <dmatlack@google.com>
Debugged-by: Sean Christopherson <seanjc@google.com>
Debugged-by: Jim Mattson <jmattson@google.com>
Debugged-by: James Houghton <jthoughton@google.com>
Signed-off-by: Venkatesh Srinivas <venkateshs@chromium.org>
Message-ID: <20260715234234.15382-2-venkateshs@chromium.org>
Reviewed-by: James Houghton <jthoughton@google.com>
Reviewed-by: Chao Gao <chao.gao@intel.com>
Cc: stable@vger.kernel.org
Fixes: ae95f566b3 ("KVM: X86: TSCDEADLINE MSR emulation fastpath", 2020-05-15)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The test asserted that the X86_FEATURE_SEV CPUID bit exactly matches
whether KVM offers KVM_X86_SEV_VM. That is not an invariant: when all
SEV ASIDs are assigned to SEV-SNP, KVM does not offer the SEV VM type
even though CPUID reports SEV, so the test aborts on an SNP-only host.
Derive SEV availability from KVM_CAP_VM_TYPES (as already done for SEV-ES
and SNP), assert only the one-way implication that a type offered by KVM
is also reported in CPUID, and TEST_REQUIRE() the SEV VM type so the test
skips cleanly when it is unavailable.
Reviewed-by: Tycho Andersen (AMD) <tycho@kernel.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-ID: <5d3c345113748f39b7982e365d241abaf3e11086.1784545391.git.dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
sev_smoke_test ran the plain SEV subtest unconditionally, gated only on
the X86_FEATURE_SEV CPUID bit, while gating SEV-ES and SNP on the
KVM_CAP_VM_TYPES bits. CPUID reporting SEV does not mean KVM offers the
SEV VM type: when all SEV ASIDs are assigned to SEV-SNP, KVM_X86_SEV_VM
is unavailable even though X86_FEATURE_SEV is set. On such a host the
test aborts in KVM_CREATE_VM instead of exercising the available modes.
Gate the SEV subtest on KVM_CAP_VM_TYPES like the others, so the test
runs the VM types the host actually offers.
Reviewed-by: Tycho Andersen (AMD) <tycho@kernel.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-ID: <2b5e7a83d277134294199a455469bb436196b902.1784545391.git.dwmw@amazon.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
mmu_destroy_caches() destroys pte_list_desc_cache and
mmu_page_header_cache, but leaves both pointers unchanged. The pointers
live in kvm.ko, and therefore survive when a vendor module is unloaded
while kvm.ko remains loaded.
If creation of pte_list_desc_cache fails during a subsequent vendor
module load, its assignment sets pte_list_desc_cache to NULL and the
error path calls mmu_destroy_caches(). mmu_page_header_cache still
points to the cache destroyed during the preceding vendor module
unload. Passing that stale pointer to kmem_cache_destroy() causes a
slab use-after-free.
Reproduce the issue on a v7.1.3 kernel with CONFIG_KASAN=y,
CONFIG_KASAN_GENERIC=y, CONFIG_KVM=m, and CONFIG_KVM_INTEL=m. A
one-shot test hook forces pte_list_desc_cache to NULL on the second
invocation of kvm_mmu_vendor_module_init():
1. Load kvm.ko and kvm-intel.ko, creating both caches.
2. Unload only kvm_intel, leaving kvm.ko loaded.
3. Reload kvm_intel and force initialization through the -ENOMEM path.
KASAN reports:
BUG: KASAN: slab-use-after-free in
kvm_mmu_vendor_module_init+0x5b/0x170 [kvm]
...
kmem_cache_destroy+0x21/0x1d0
kvm_mmu_vendor_module_init+0x5b/0x170 [kvm]
...
Allocated by task 16817:
__kmem_cache_create_args+0x12c/0x3b0
__kmem_cache_create.constprop.0+0xb6/0xf0 [kvm]
kvm_mmu_vendor_module_init+0x13b/0x170 [kvm]
...
Freed by task 16820:
kmem_cache_destroy+0x117/0x1d0
kvm_mmu_vendor_module_exit+0x21/0x30 [kvm]
Clear both pointers immediately after destroying their caches so that
the stored state reflects the caches' lifetime and repeated cleanup is
safe.
With the fix applied, the same injected vendor module reload fails with
-ENOMEM as expected and produces no KASAN report.
Fixes: cb498ea2ce ("KVM: Portability: Combine kvm_init and kvm_init_x86")
Cc: stable@vger.kernel.org
Signed-off-by: Phil Rosenthal <phil@phil.gs>
Message-ID: <20260718-kvm-mmu-cache-uaf-v3-1-e103b93c74e1@phil.gs>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_mmu_zap_oldest_mmu_pages() excludes a shadow page whose root_count
is non-zero from top-level reclaim, because such a page cannot be
freed. The path in mmu_page_zap_pte() that recursively zaps a parentless
nested TDP child has no such check. As a result, a shadow page can
be zapped even if the page itself can't be freed; as the comment in
kvm_mmu_zap_oldest_mmu_pages() notes, zapping it will just force vCPUs
to rebuild the page.
As in top-level reclaim, do not recursively prepare zapping of a
nested TDP child whose root_count is non-zero.
Fixes: 2de4085ccc ("KVM: x86/MMU: Recursively zap nested TDP SPs when zapping last/only parent")
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Check for a "stale" page fault, i.e. for an invalid and/or obsolete root,
after making MMU pages available for the shadow MMU. If reclaiming shadow
pages zaps an in-use root, i.e. marks it invalid, then KVM will attempt to
map memory into an invalid root. On its own, populating an invalid root is
"fine", but because child shadow pages inherit their parent's role, any
children created during the map/fetch will be created as invalid pages,
thus violating KVM's invariant that invalid pages are never on the list of
active MMU pages.
Note, the underlying flaw has existed since KVM first started tracking
invalid roots in 2008 (commit 2e53d63acb, "KVM: MMU: ignore zapped root
pagetables"), but the true badness only came along in 2020 (Linux 5.9)
with the invariant that invalid shadow pages can't be on the list of
active pages.
Note #2, inheriting role.invalid when creating child shadow pages is also
far from ideal; that flaw will be addressed separately.
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Fixes: f95eec9bed ("KVM: x86/mmu: Don't put invalid SPs back on the list of active pages")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
free_nested() frees the shadow VMCS while vmcs01 still points to it. But
because it is asynchronous with respect to loaded_vmcs_clear(), the vCPU
might migrate before the pointer is cleared and __loaded_vmcs_clear()
may then execute VMCLEAR.
The VMCS needs to stay attached until its explicit VMCLEAR completes, but
then it can be hidden and the page safely freed.
Fixes: 355f4fb140 ("kvm: nVMX: VMCLEAR an active shadow VMCS after last use")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
eprobe_dyn_event_match() checks if the target event system in argv[0]
matches ep->event_system using strncmp(ep->event_system, argv[0], len).
However, if ep->event_system is longer than len (e.g. "eprobes" vs
"ep/event"), strncmp() still returns 0 because the first len characters
match.
Check that ep->event_system[len] is '\0' to ensure exact system name
matching.
Link: https://lore.kernel.org/all/178454235856.290363.14872590900774231133.stgit@devnote2/
Fixes: 7d5fda1c84 ("tracing: Fix event probe removal from dynamic events")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
In __set_print_fmt(), LEN_OR_ZERO is defined as (len ? len - pos : 0).
If len is non-zero but smaller than pos, len - pos evaluates to a negative
integer. When passed as a size argument to snprintf(), this negative value
is cast to a large unsigned size_t, bypassing buffer size limits.
Ensure len > pos before subtracting to avoid integer underflow.
Link: https://lore.kernel.org/all/178454234934.290363.15247317871499514139.stgit@devnote2/
Fixes: 5bf652aaf4 ("tracing/probes: Integrate duplicate set_print_fmt()")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
If trace_probe_log.argc is 0 in __trace_probe_log_err(), the loop
constructing the command string will not execute and p will remain equal to
command. Writing to *(p - 1) will cause an out-of-bounds access before
command. This should not happen, but better to be treated.
Reject if trace_probe_log.argc is 0.
Link: https://lore.kernel.org/all/178454233992.290363.18323091580600697731.stgit@devnote2/
Fixes: ab105a4fb8 ("tracing: Use tracing error_log with probe events")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
In trace_probe_match_command_args(), a stack buffer buf[MAX_ARGSTR_LEN + 1]
(256 bytes) is used to format "<name>=<comm>". However, since name can
be up to 32 bytes (MAX_ARG_NAME_LEN) and comm up to 255 bytes
(MAX_ARGSTR_LEN), the formatted string can exceed 256 bytes and get
truncated by snprintf(), causing spurious argument matching failures.
Instead of formatting into a temporary buffer on stack, compare the
argument name, the '=' delimiter, and the comm expression directly.
Link: https://lore.kernel.org/all/178454233010.290363.10428767141343428804.stgit@devnote2/
Fixes: eb5bf81330 ("tracing/kprobe: Add per-probe delete from event")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Pull misc fixes from Andrew Morton:
"12 hotfixes. 8 are cc:stable and the remainder address post-7.1 issues
or aren't considered appropriate for backporting. 10 are for MM.
All are singletons - please see the relevant changelogs for details"
* tag 'mm-hotfixes-stable-2026-07-20-11-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm/memory-failure: trace: change memory_failure_event to ras subsystem
mm: page_reporting: allow driver to set batch capacity
mm/kmemleak: fix checksum computation for per-cpu objects
mm/damon/core: disallow overlapping input ranges for damon_set_regions()
MAINTAINERS: add Usama as a THP reviewer
fat: avoid stack overflow warning
mm/damon/core: validate ranges in damon_set_regions()
m68k: avoid -Wunused-but-set-parameter in clear_user_page()
mm/huge_memory: set PG_has_hwpoisoned only after new folio head is established
mm/page_vma_mapped: fix device-private PMD handling
MAINTAINERS: s/SeongJae/SJ/
userfaultfd: prevent registration of special VMAs
Pull crypto fix from Herbert Xu:
- Fix potential crash in rhashtable walk
* tag 'v7.2-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
rhashtable: clear stale iter->p on table restart
The OCC poll response parser walks a counted list of sensor data blocks.
It used the static backing-array capacity as the parse boundary, but a
transport response makes only data_length bytes current and valid. A
truncated response can therefore make the parser consume a block header or
block extent outside the current response.
Use data_length as the parent boundary, prove the fixed poll header and
each current block header before reading them, and prove the complete block
before advancing. Keep parsed sensor metadata local until the complete
response has passed validation, then publish it. Propagate
malformed-response errors before publishing the OCC as active.
Fixes: aa195fe49b ("hwmon (occ): Parse OCC poll response")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Link: https://lore.kernel.org/r/20260720115826.14813-1-pengpeng@iscas.ac.cn
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
When monitoring a large number of events (e.g., with wildcards such as
--event 'syscalls:sys_enter_*'), many matched events will return a count
of zero. This clutters the output, making it difficult to spot the
active events.
Add a new option --hide-zero-events to suppress printing events that
have a count of zero.
To prevent formatting and diagnostic issues, the zero-skipping logic
implements the following rules:
1. In metric-only mode (i.e., --metric-only), columns must remain
aligned in the output grid. We evaluate config->metric_only first
to avoid skipping zero-valued columns, preventing values from
shifting left and aligning under incorrect headers
2. For explicitly requested events, we ensure they are not silently
hidden if they are unsupported. We only hide a zero-count event
if counter->supported is true, ensuring that unsupported explicit
events still report "<not supported>"
Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
