kernel/linux.git/tools/perf/util/machine.c, branch v6.1.168

perf machine: Avoid out of bounds LBR memory read

2023-11-20T10:52:12+00:00

[ Upstream commit ab8ce150781d326c6bfbe1e09f175ffde1186f80 ] Running perf top with address sanitizer and "--call-graph=lbr" fails due to reading sample 0 when no samples exist. Add a guard to prevent this. Fixes: e2b23483eb1d ("perf machine: Factor out lbr_callchain_add_lbr_ip()") Signed-off-by: Ian Rogers Cc: K Prateek Nayak Cc: Ravi Bangoria Cc: Sandipan Das Cc: Anshuman Khandual Cc: German Gomez Cc: James Clark Cc: Nick Terrell Cc: Sean Christopherson Cc: Changbin Du Cc: liuwenyu Cc: Yang Jihong Cc: Masami Hiramatsu Cc: Miguel Ojeda Cc: Song Liu Cc: Leo Yan Cc: Kajol Jain Cc: Andi Kleen Cc: Kan Liang Cc: Athira Rajeev Cc: Yanteng Si Cc: Liam Howlett Cc: Paolo Bonzini Link: https://lore.kernel.org/r/20231024222353.3024098-3-irogers@google.com Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf machine: Remove unused struct process_args

2022-10-06T11:03:51+00:00

After commit a93f0e551af9 ("perf symbols: Get kernel start address by symbol name"), no one uses struct process_args any more, so remove it. Signed-off-by: Yuan Can Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/linux-perf-users/20220927013931.110475-2-yuancan@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Fix missing free of machine->kallsyms_filename

2022-08-10T13:44:02+00:00

Add missing free of machine->kallsyms_filename to machine__exit(). Fixes: a5367ecb5353fbf2 ("perf tools: Automatically use guest kcore_dir if present") Signed-off-by: Adrian Hunter Acked-by: Ian Rogers Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lore.kernel.org/r/20220809130758.12800-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Handle injected guest kernel mmap event

2022-07-20T14:08:37+00:00

If a kernel mmap event was recorded inside a guest and injected into a host perf.data file, then it will match a host mmap_name not a guest mmap_name, see machine__set_mmap_name(). So try matching a host mmap_name in that case. Signed-off-by: Adrian Hunter Acked-by: Ian Rogers Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-27-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Use realloc_array_as_needed() in machine__set_current_tid()

2022-07-20T14:08:37+00:00

Prepare machine__set_current_tid() for use with guest machines that do not currently have a machine->env->nr_cpus_avail value by making use of realloc_array_as_needed(). Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220711093218.10967-26-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf buildid-list: Add a "-m" option to show kernel and modules build-ids

2022-07-18T19:35:34+00:00

This new option displays all of the information needed to do external BuildID-based symbolization of kernel stack traces, such as those collected by bpf_get_stackid(). For each kernel module plus the main kernel, it displays the BuildID, the start and end virtual addresses of that module's text range (rounded out to page boundaries), and the pathname of the module. When run as a non-privileged user, the actual addresses of the modules' text ranges are not available, so the tools displays "0, " for kernel modules and "0, 0xffffffffffffffff" for the kernel itself. Sample output: root# perf buildid-list -m cf6df852fd4da122d616153353cc8f560fd12fe0 ffffffffa5400000 ffffffffa6001e27 [kernel.kallsyms] 1aa7209aa2acb067d66ed6cf7676d65066384d61 ffffffffc0087000 ffffffffc008b000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/sha512_generic.ko 3857815b5bf0183697b68f8fe0ea06121644041e ffffffffc008c000 ffffffffc0098000 /lib/modules/5.15.15-1rodete2-amd64/kernel/arch/x86/crypto/sha512-ssse3.ko 4081fde0bca2bc097cb3e9d1efcb836047d485f1 ffffffffc0099000 ffffffffc009f000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/acpi/button.ko 1ef81ba4890552ea6b0314f9635fc43fc8cef568 ffffffffc00a4000 ffffffffc00aa000 /lib/modules/5.15.15-1rodete2-amd64/kernel/crypto/cryptd.ko cc5c985506cb240d7d082b55ed260cbb851f983e ffffffffc00af000 ffffffffc00b6000 /lib/modules/5.15.15-1rodete2-amd64/kernel/drivers/i2c/busses/i2c-piix4.ko [...] Committer notes: u64 formatter should be PRIx64 for printing as hex numbers, fix this: 28 5.28 debian:experimental-x-mips : FAIL gcc version 11.2.0 (Debian 11.2.0-18) builtin-buildid-list.c: In function 'buildid__map_cb': builtin-buildid-list.c:32:24: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=] 32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end); | ~~~~^ ~~~~~~~~~~ | | | | long unsigned int u64 {aka long long unsigned int} | %16llx builtin-buildid-list.c:32:30: error: format '%lx' expects argument of type 'long unsigned int', but argument 4 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=] 32 | printf("%s %16lx %16lx", bid_buf, map->start, map->end); | ~~~~^ ~~~~~~~~ | | | | long unsigned int u64 {aka long long unsigned int} | %16llx cc1: all warnings being treated as errors Signed-off-by: Blake Jones Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Ian Rogers Cc: Ingo Molnar Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20220629213632.3899212-1-blakejones@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add guest_code support

2022-05-23T13:18:38+00:00

A common case for KVM test programs is that the test program acts as the hypervisor, creating, running and destroying the virtual machine, and providing the guest object code from its own object code. In this case, the VM is not running an OS, but only the functions loaded into it by the hypervisor test program, and conveniently, loaded at the same virtual addresses. Normally to resolve addresses, MMAP events are needed to map addresses back to the object code and debug symbols for that object code. Currently, there is no way to get such mapping information from guests but, in the scenario described above, the guest has the same mappings as the hypervisor, so support for that scenario can be achieved. To support that, copy the host thread's maps to the guest thread's maps. Note, we do not discover the guest until we encounter a guest event, which works well because it is not until then that we know that the host thread's maps have been set up. Typically the main function for the guest object code is called "guest_code", hence the name chosen for this feature. Note, that is just a convention, the function could be named anything, and the tools do not care. This is primarily aimed at supporting Intel PT, or similar, where trace data can be recorded for a guest. Refer to the final patch in this series "perf intel-pt: Add guest_code support" for an example. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Leo Yan Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220517131011.6117-4-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Factor out thread__set_guest_comm()

2022-05-23T13:18:27+00:00

Factor out thread__set_guest_comm() so it can be reused. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Leo Yan Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220517131011.6117-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Add machine to machines back pointer

2022-05-23T13:18:06+00:00

When dealing with guest machines, it can be necessary to get a reference to the host machine. Add a machines pointer to struct machine to make that possible. Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Ian Rogers Cc: Jiri Olsa Cc: Leo Yan Cc: Namhyung Kim Cc: kvm@vger.kernel.org Link: https://lore.kernel.org/r/20220517131011.6117-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf unwind: Don't show unwind error messages when augmenting frame pointer stack

2022-04-09T15:34:29+00:00

Commit Fixes: b9f6fbb3b2c29736 ("perf arm64: Inject missing frames when using 'perf record --call-graph=fp'") intended to add a 'best effort' DWARF unwind that improved the frame pointer stack in most scenarios. It's expected that the unwind will fail sometimes, but this shouldn't be reported as an error. It only works when the return address can be determined from the contents of the link register alone. Fix the error shown when the unwinder requires extra registers by adding a new flag that suppresses error messages. This flag is not set in the normal --call-graph=dwarf unwind mode so that behavior is not changed. Fixes: b9f6fbb3b2c29736 ("perf arm64: Inject missing frames when using 'perf record --call-graph=fp'") Reported-by: John Garry Signed-off-by: James Clark Tested-by: John Garry Cc: Alexander Shishkin Cc: Alexandre Truong Cc: German Gomez Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Link: https://lore.kernel.org/r/20220406145651.1392529-1-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo