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2022-01-12Merge tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block updates from Jens Axboe: - Unify where the struct request handling code is located in the blk-mq code (Christoph) - Header cleanups (Christoph) - Clean up the io_context handling code (Christoph, me) - Get rid of ->rq_disk in struct request (Christoph) - Error handling fix for add_disk() (Christoph) - request allocation cleanusp (Christoph) - Documentation updates (Eric, Matthew) - Remove trivial crypto unregister helper (Eric) - Reduce shared tag overhead (John) - Reduce poll_stats memory overhead (me) - Known indirect function call for dio (me) - Use atomic references for struct request (me) - Support request list issue for block and NVMe (me) - Improve queue dispatch pinning (Ming) - Improve the direct list issue code (Keith) - BFQ improvements (Jan) - Direct completion helper and use it in mmc block (Sebastian) - Use raw spinlock for the blktrace code (Wander) - fsync error handling fix (Ye) - Various fixes and cleanups (Lukas, Randy, Yang, Tetsuo, Ming, me) * tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block: (132 commits) MAINTAINERS: add entries for block layer documentation docs: block: remove queue-sysfs.rst docs: sysfs-block: document virt_boundary_mask docs: sysfs-block: document stable_writes docs: sysfs-block: fill in missing documentation from queue-sysfs.rst docs: sysfs-block: add contact for nomerges docs: sysfs-block: sort alphabetically docs: sysfs-block: move to stable directory block: don't protect submit_bio_checks by q_usage_counter block: fix old-style declaration nvme-pci: fix queue_rqs list splitting block: introduce rq_list_move block: introduce rq_list_for_each_safe macro block: move rq_list macros to blk-mq.h block: drop needless assignment in set_task_ioprio() block: remove unnecessary trailing '\' bio.h: fix kernel-doc warnings block: check minor range in device_add_disk() block: use "unsigned long" for blk_validate_block_size(). block: fix error unwinding in device_add_disk ...
2022-01-10Merge tag '5.17-net-next' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core ---- - Defer freeing TCP skbs to the BH handler, whenever possible, or at least perform the freeing outside of the socket lock section to decrease cross-CPU allocator work and improve latency. - Add netdevice refcount tracking to locate sources of netdevice and net namespace refcount leaks. - Make Tx watchdog less intrusive - avoid pausing Tx and restarting all queues from a single CPU removing latency spikes. - Various small optimizations throughout the stack from Eric Dumazet. - Make netdev->dev_addr[] constant, force modifications to go via appropriate helpers to allow us to keep addresses in ordered data structures. - Replace unix_table_lock with per-hash locks, improving performance of bind() calls. - Extend skb drop tracepoint with a drop reason. - Allow SO_MARK and SO_PRIORITY setsockopt under CAP_NET_RAW. BPF --- - New helpers: - bpf_find_vma(), find and inspect VMAs for profiling use cases - bpf_loop(), runtime-bounded loop helper trading some execution time for much faster (if at all converging) verification - bpf_strncmp(), improve performance, avoid compiler flakiness - bpf_get_func_arg(), bpf_get_func_ret(), bpf_get_func_arg_cnt() for tracing programs, all inlined by the verifier - Support BPF relocations (CO-RE) in the kernel loader. - Further the support for BTF_TYPE_TAG annotations. - Allow access to local storage in sleepable helpers. - Convert verifier argument types to a composable form with different attributes which can be shared across types (ro, maybe-null). - Prepare libbpf for upcoming v1.0 release by cleaning up APIs, creating new, extensible ones where missing and deprecating those to be removed. Protocols --------- - WiFi (mac80211/cfg80211): - notify user space about long "come back in N" AP responses, allow it to react to such temporary rejections - allow non-standard VHT MCS 10/11 rates - use coarse time in airtime fairness code to save CPU cycles - Bluetooth: - rework of HCI command execution serialization to use a common queue and work struct, and improve handling errors reported in the middle of a batch of commands - rework HCI event handling to use skb_pull_data, avoiding packet parsing pitfalls - support AOSP Bluetooth Quality Report - SMC: - support net namespaces, following the RDMA model - improve connection establishment latency by pre-clearing buffers - introduce TCP ULP for automatic redirection to SMC - Multi-Path TCP: - support ioctls: SIOCINQ, OUTQ, and OUTQNSD - support socket options: IP_TOS, IP_FREEBIND, IP_TRANSPARENT, IPV6_FREEBIND, and IPV6_TRANSPARENT, TCP_CORK and TCP_NODELAY - support cmsgs: TCP_INQ - improvements in the data scheduler (assigning data to subflows) - support fastclose option (quick shutdown of the full MPTCP connection, similar to TCP RST in regular TCP) - MCTP (Management Component Transport) over serial, as defined by DMTF spec DSP0253 - "MCTP Serial Transport Binding". Driver API ---------- - Support timestamping on bond interfaces in active/passive mode. - Introduce generic phylink link mode validation for drivers which don't have any quirks and where MAC capability bits fully express what's supported. Allow PCS layer to participate in the validation. Convert a number of drivers. - Add support to set/get size of buffers on the Rx rings and size of the tx copybreak buffer via ethtool. - Support offloading TC actions as first-class citizens rather than only as attributes of filters, improve sharing and device resource utilization. - WiFi (mac80211/cfg80211): - support forwarding offload (ndo_fill_forward_path) - support for background radar detection hardware - SA Query Procedures offload on the AP side New hardware / drivers ---------------------- - tsnep - FPGA based TSN endpoint Ethernet MAC used in PLCs with real-time requirements for isochronous communication with protocols like OPC UA Pub/Sub. - Qualcomm BAM-DMUX WWAN - driver for data channels of modems integrated into many older Qualcomm SoCs, e.g. MSM8916 or MSM8974 (qcom_bam_dmux). - Microchip LAN966x multi-port Gigabit AVB/TSN Ethernet Switch driver with support for bridging, VLANs and multicast forwarding (lan966x). - iwlmei driver for co-operating between Intel's WiFi driver and Intel's Active Management Technology (AMT) devices. - mse102x - Vertexcom MSE102x Homeplug GreenPHY chips - Bluetooth: - MediaTek MT7921 SDIO devices - Foxconn MT7922A - Realtek RTL8852AE Drivers ------- - Significantly improve performance in the datapaths of: lan78xx, ax88179_178a, lantiq_xrx200, bnxt. - Intel Ethernet NICs: - igb: support PTP/time PEROUT and EXTTS SDP functions on 82580/i354/i350 adapters - ixgbevf: new PF -> VF mailbox API which avoids the risk of mailbox corruption with ESXi - iavf: support configuration of VLAN features of finer granularity, stacked tags and filtering - ice: PTP support for new E822 devices with sub-ns precision - ice: support firmware activation without reboot - Mellanox Ethernet NICs (mlx5): - expose control over IRQ coalescing mode (CQE vs EQE) via ethtool - support TC forwarding when tunnel encap and decap happen between two ports of the same NIC - dynamically size and allow disabling various features to save resources for running in embedded / SmartNIC scenarios - Broadcom Ethernet NICs (bnxt): - use page frag allocator to improve Rx performance - expose control over IRQ coalescing mode (CQE vs EQE) via ethtool - Other Ethernet NICs: - amd-xgbe: add Ryzen 6000 (Yellow Carp) Ethernet support - Microsoft cloud/virtual NIC (mana): - add XDP support (PASS, DROP, TX) - Mellanox Ethernet switches (mlxsw): - initial support for Spectrum-4 ASICs - VxLAN with IPv6 underlay - Marvell Ethernet switches (prestera): - support flower flow templates - add basic IP forwarding support - NXP embedded Ethernet switches (ocelot & felix): - support Per-Stream Filtering and Policing (PSFP) - enable cut-through forwarding between ports by default - support FDMA to improve packet Rx/Tx to CPU - Other embedded switches: - hellcreek: improve trapping management (STP and PTP) packets - qca8k: support link aggregation and port mirroring - Qualcomm 802.11ax WiFi (ath11k): - qca6390, wcn6855: enable 802.11 power save mode in station mode - BSS color change support - WCN6855 hw2.1 support - 11d scan offload support - scan MAC address randomization support - full monitor mode, only supported on QCN9074 - qca6390/wcn6855: report signal and tx bitrate - qca6390: rfkill support - qca6390/wcn6855: regdb.bin support - Intel WiFi (iwlwifi): - support SAR GEO Offset Mapping (SGOM) and Time-Aware-SAR (TAS) in cooperation with the BIOS - support for Optimized Connectivity Experience (OCE) scan - support firmware API version 68 - lots of preparatory work for the upcoming Bz device family - MediaTek WiFi (mt76): - Specific Absorption Rate (SAR) support - mt7921: 160 MHz channel support - RealTek WiFi (rtw88): - Specific Absorption Rate (SAR) support - scan offload - Other WiFi NICs - ath10k: support fetching (pre-)calibration data from nvmem - brcmfmac: configure keep-alive packet on suspend - wcn36xx: beacon filter support" * tag '5.17-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2048 commits) tcp: tcp_send_challenge_ack delete useless param `skb` net/qla3xxx: Remove useless DMA-32 fallback configuration rocker: Remove useless DMA-32 fallback configuration hinic: Remove useless DMA-32 fallback configuration lan743x: Remove useless DMA-32 fallback configuration net: enetc: Remove useless DMA-32 fallback configuration cxgb4vf: Remove useless DMA-32 fallback configuration cxgb4: Remove useless DMA-32 fallback configuration cxgb3: Remove useless DMA-32 fallback configuration bnx2x: Remove useless DMA-32 fallback configuration et131x: Remove useless DMA-32 fallback configuration be2net: Remove useless DMA-32 fallback configuration vmxnet3: Remove useless DMA-32 fallback configuration bna: Simplify DMA setting net: alteon: Simplify DMA setting myri10ge: Simplify DMA setting qlcnic: Simplify DMA setting net: allwinner: Fix print format page_pool: remove spinlock in page_pool_refill_alloc_cache() amt: fix wrong return type of amt_send_membership_update() ...
2022-01-05tracing: Tag trace_percpu_buffer as a percpu pointerNaveen N. Rao
Tag trace_percpu_buffer as a percpu pointer to resolve warnings reported by sparse: /linux/kernel/trace/trace.c:3218:46: warning: incorrect type in initializer (different address spaces) /linux/kernel/trace/trace.c:3218:46: expected void const [noderef] __percpu *__vpp_verify /linux/kernel/trace/trace.c:3218:46: got struct trace_buffer_struct * /linux/kernel/trace/trace.c:3234:9: warning: incorrect type in initializer (different address spaces) /linux/kernel/trace/trace.c:3234:9: expected void const [noderef] __percpu *__vpp_verify /linux/kernel/trace/trace.c:3234:9: got int * Link: https://lkml.kernel.org/r/ebabd3f23101d89cb75671b68b6f819f5edc830b.1640255304.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Fixes: 07d777fe8c398 ("tracing: Add percpu buffers for trace_printk()") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-05tracing: Fix check for trace_percpu_buffer validity in get_trace_buf()Naveen N. Rao
With the new osnoise tracer, we are seeing the below splat: Kernel attempted to read user page (c7d880000) - exploit attempt? (uid: 0) BUG: Unable to handle kernel data access on read at 0xc7d880000 Faulting instruction address: 0xc0000000002ffa10 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries ... NIP [c0000000002ffa10] __trace_array_vprintk.part.0+0x70/0x2f0 LR [c0000000002ff9fc] __trace_array_vprintk.part.0+0x5c/0x2f0 Call Trace: [c0000008bdd73b80] [c0000000001c49cc] put_prev_task_fair+0x3c/0x60 (unreliable) [c0000008bdd73be0] [c000000000301430] trace_array_printk_buf+0x70/0x90 [c0000008bdd73c00] [c0000000003178b0] trace_sched_switch_callback+0x250/0x290 [c0000008bdd73c90] [c000000000e70d60] __schedule+0x410/0x710 [c0000008bdd73d40] [c000000000e710c0] schedule+0x60/0x130 [c0000008bdd73d70] [c000000000030614] interrupt_exit_user_prepare_main+0x264/0x270 [c0000008bdd73de0] [c000000000030a70] syscall_exit_prepare+0x150/0x180 [c0000008bdd73e10] [c00000000000c174] system_call_vectored_common+0xf4/0x278 osnoise tracer on ppc64le is triggering osnoise_taint() for negative duration in get_int_safe_duration() called from trace_sched_switch_callback()->thread_exit(). The problem though is that the check for a valid trace_percpu_buffer is incorrect in get_trace_buf(). The check is being done after calculating the pointer for the current cpu, rather than on the main percpu pointer. Fix the check to be against trace_percpu_buffer. Link: https://lkml.kernel.org/r/a920e4272e0b0635cf20c444707cbce1b2c8973d.1640255304.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Fixes: e2ace001176dc9 ("tracing: Choose static tp_printk buffer by explicit nesting count") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2021-12-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-12-30 The following pull-request contains BPF updates for your *net-next* tree. We've added 72 non-merge commits during the last 20 day(s) which contain a total of 223 files changed, 3510 insertions(+), 1591 deletions(-). The main changes are: 1) Automatic setrlimit in libbpf when bpf is memcg's in the kernel, from Andrii. 2) Beautify and de-verbose verifier logs, from Christy. 3) Composable verifier types, from Hao. 4) bpf_strncmp helper, from Hou. 5) bpf.h header dependency cleanup, from Jakub. 6) get_func_[arg|ret|arg_cnt] helpers, from Jiri. 7) Sleepable local storage, from KP. 8) Extend kfunc with PTR_TO_CTX, PTR_TO_MEM argument support, from Kumar. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-20blktrace: switch trace spinlock to a raw spinlockWander Lairson Costa
The running_trace_lock protects running_trace_list and is acquired within the tracepoint which implies disabled preemption. The spinlock_t typed lock can not be acquired with disabled preemption on PREEMPT_RT because it becomes a sleeping lock. The runtime of the tracepoint depends on the number of entries in running_trace_list and has no limit. The blk-tracer is considered debug code and higher latencies here are okay. Make running_trace_lock a raw_spinlock_t. Signed-off-by: Wander Lairson Costa <wander@redhat.com> Link: https://lore.kernel.org/r/20211220192827.38297-1-wander@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-12-18bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.Hao Luo
Some helper functions may modify its arguments, for example, bpf_d_path, bpf_get_stack etc. Previously, their argument types were marked as ARG_PTR_TO_MEM, which is compatible with read-only mem types, such as PTR_TO_RDONLY_BUF. Therefore it's legitimate, but technically incorrect, to modify a read-only memory by passing it into one of such helper functions. This patch tags the bpf_args compatible with immutable memory with MEM_RDONLY flag. The arguments that don't have this flag will be only compatible with mutable memory types, preventing the helper from modifying a read-only memory. The bpf_args that have MEM_RDONLY are compatible with both mutable memory and immutable memory. Signed-off-by: Hao Luo <haoluo@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211217003152.48334-9-haoluo@google.com
2021-12-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-16add missing bpf-cgroup.h includesJakub Kicinski
We're about to break the cgroup-defs.h -> bpf-cgroup.h dependency, make sure those who actually need more than the definition of struct cgroup_bpf include bpf-cgroup.h explicitly. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/bpf/20211216025538.1649516-3-kuba@kernel.org
2021-12-13bpf: Add get_func_[arg|ret|arg_cnt] helpersJiri Olsa
Adding following helpers for tracing programs: Get n-th argument of the traced function: long bpf_get_func_arg(void *ctx, u32 n, u64 *value) Get return value of the traced function: long bpf_get_func_ret(void *ctx, u64 *value) Get arguments count of the traced function: long bpf_get_func_arg_cnt(void *ctx) The trampoline now stores number of arguments on ctx-8 address, so it's easy to verify argument index and find return value argument's position. Moving function ip address on the trampoline stack behind the number of functions arguments, so it's now stored on ctx-16 address if it's needed. All helpers above are inlined by verifier. Also bit unrelated small change - using newly added function bpf_prog_has_trampoline in check_get_func_ip. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211208193245.172141-5-jolsa@kernel.org
2021-12-10Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Andrii Nakryiko says: ==================== bpf-next 2021-12-10 v2 We've added 115 non-merge commits during the last 26 day(s) which contain a total of 182 files changed, 5747 insertions(+), 2564 deletions(-). The main changes are: 1) Various samples fixes, from Alexander Lobakin. 2) BPF CO-RE support in kernel and light skeleton, from Alexei Starovoitov. 3) A batch of new unified APIs for libbpf, logging improvements, version querying, etc. Also a batch of old deprecations for old APIs and various bug fixes, in preparation for libbpf 1.0, from Andrii Nakryiko. 4) BPF documentation reorganization and improvements, from Christoph Hellwig and Dave Tucker. 5) Support for declarative initialization of BPF_MAP_TYPE_PROG_ARRAY in libbpf, from Hengqi Chen. 6) Verifier log fixes, from Hou Tao. 7) Runtime-bounded loops support with bpf_loop() helper, from Joanne Koong. 8) Extend branch record capturing to all platforms that support it, from Kajol Jain. 9) Light skeleton codegen improvements, from Kumar Kartikeya Dwivedi. 10) bpftool doc-generating script improvements, from Quentin Monnet. 11) Two libbpf v0.6 bug fixes, from Shuyi Cheng and Vincent Minet. 12) Deprecation warning fix for perf/bpf_counter, from Song Liu. 13) MAX_TAIL_CALL_CNT unification and MIPS build fix for libbpf, from Tiezhu Yang. 14) BTF_KING_TYPE_TAG follow-up fixes, from Yonghong Song. 15) Selftests fixes and improvements, from Ilya Leoshkevich, Jean-Philippe Brucker, Jiri Olsa, Maxim Mikityanskiy, Tirthendu Sarkar, Yucong Sun, and others. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (115 commits) libbpf: Add "bool skipped" to struct bpf_map libbpf: Fix typo in btf__dedup@LIBBPF_0.0.2 definition bpftool: Switch bpf_object__load_xattr() to bpf_object__load() selftests/bpf: Remove the only use of deprecated bpf_object__load_xattr() selftests/bpf: Add test for libbpf's custom log_buf behavior selftests/bpf: Replace all uses of bpf_load_btf() with bpf_btf_load() libbpf: Deprecate bpf_object__load_xattr() libbpf: Add per-program log buffer setter and getter libbpf: Preserve kernel error code and remove kprobe prog type guessing libbpf: Improve logging around BPF program loading libbpf: Allow passing user log setting through bpf_object_open_opts libbpf: Allow passing preallocated log_buf when loading BTF into kernel libbpf: Add OPTS-based bpf_btf_load() API libbpf: Fix bpf_prog_load() log_buf logic for log_level 0 samples/bpf: Remove unneeded variable bpf: Remove redundant assignment to pointer t selftests/bpf: Fix a compilation warning perf/bpf_counter: Use bpf_map_create instead of bpf_create_map samples: bpf: Fix 'unknown warning group' build warning on Clang samples: bpf: Fix xdp_sample_user.o linking with Clang ... ==================== Link: https://lore.kernel.org/r/20211210234746.2100561-1-andrii@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-09tracing: Fix possible memory leak in __create_synth_event() error pathMiaoqian Lin
There's error paths in __create_synth_event() after the argv is allocated that fail to free it. Add a jump to free it when necessary. Link: https://lkml.kernel.org/r/20211209024317.11783-1-linmq006@gmail.com Suggested-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Miaoqian Lin <linmq006@gmail.com> [ Fixed up the patch and change log ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-12-08ftrace: Add cleanup to unregister_ftrace_direct_multiJiri Olsa
Adding ops cleanup to unregister_ftrace_direct_multi, so it can be reused in another register call. Link: https://lkml.kernel.org/r/20211206182032.87248-3-jolsa@kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Fixes: f64dd4627ec6 ("ftrace: Add multi direct register/unregister interface") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-12-08ftrace: Use direct_ops hash in unregister_ftrace_directJiri Olsa
Now when we have *direct_multi interface the direct_functions hash is no longer owned just by direct_ops. It's also used by any other ftrace_ops passed to *direct_multi interface. Thus to find out that we are unregistering the last function from direct_ops, we need to check directly direct_ops's hash. Link: https://lkml.kernel.org/r/20211206182032.87248-2-jolsa@kernel.org Cc: Ingo Molnar <mingo@redhat.com> Cc: Heiko Carstens <hca@linux.ibm.com> Fixes: f64dd4627ec6 ("ftrace: Add multi direct register/unregister interface") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-12-06bpf: Remove config check to enable bpf support for branch recordsKajol Jain
Branch data available to BPF programs can be very useful to get stack traces out of userspace application. Commit fff7b64355ea ("bpf: Add bpf_read_branch_records() helper") added BPF support to capture branch records in x86. Enable this feature also for other architectures as well by removing checks specific to x86. If an architecture doesn't support branch records, bpf_read_branch_records() still has appropriate checks and it will return an -EINVAL in that scenario. Based on UAPI helper doc in include/uapi/linux/bpf.h, unsupported architectures should return -ENOENT in such case. Hence, update the appropriate check to return -ENOENT instead. Selftest 'perf_branches' result on power9 machine which has the branch stacks support: - Before this patch: [command]# ./test_progs -t perf_branches #88/1 perf_branches/perf_branches_hw:FAIL #88/2 perf_branches/perf_branches_no_hw:OK #88 perf_branches:FAIL Summary: 0/1 PASSED, 0 SKIPPED, 1 FAILED - After this patch: [command]# ./test_progs -t perf_branches #88/1 perf_branches/perf_branches_hw:OK #88/2 perf_branches/perf_branches_no_hw:OK #88 perf_branches:OK Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED Selftest 'perf_branches' result on power9 machine which doesn't have branch stack report: - After this patch: [command]# ./test_progs -t perf_branches #88/1 perf_branches/perf_branches_hw:SKIP #88/2 perf_branches/perf_branches_no_hw:OK #88 perf_branches:OK Summary: 1/1 PASSED, 1 SKIPPED, 0 FAILED Fixes: fff7b64355eac ("bpf: Add bpf_read_branch_records() helper") Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Kajol Jain <kjain@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20211206073315.77432-1-kjain@linux.ibm.com
2021-12-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-01tracing: Fix a kmemleak false positive in tracing_mapChen Jun
Doing the command: echo 'hist:key=common_pid.execname,common_timestamp' > /sys/kernel/debug/tracing/events/xxx/trigger Triggers many kmemleak reports: unreferenced object 0xffff0000c7ea4980 (size 128): comm "bash", pid 338, jiffies 4294912626 (age 9339.324s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000f3469921>] kmem_cache_alloc_trace+0x4c0/0x6f0 [<0000000054ca40c3>] hist_trigger_elt_data_alloc+0x140/0x178 [<00000000633bd154>] tracing_map_init+0x1f8/0x268 [<000000007e814ab9>] event_hist_trigger_func+0xca0/0x1ad0 [<00000000bf8520ed>] trigger_process_regex+0xd4/0x128 [<00000000f549355a>] event_trigger_write+0x7c/0x120 [<00000000b80f898d>] vfs_write+0xc4/0x380 [<00000000823e1055>] ksys_write+0x74/0xf8 [<000000008a9374aa>] __arm64_sys_write+0x24/0x30 [<0000000087124017>] do_el0_svc+0x88/0x1c0 [<00000000efd0dcd1>] el0_svc+0x1c/0x28 [<00000000dbfba9b3>] el0_sync_handler+0x88/0xc0 [<00000000e7399680>] el0_sync+0x148/0x180 unreferenced object 0xffff0000c7ea4980 (size 128): comm "bash", pid 338, jiffies 4294912626 (age 9339.324s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000f3469921>] kmem_cache_alloc_trace+0x4c0/0x6f0 [<0000000054ca40c3>] hist_trigger_elt_data_alloc+0x140/0x178 [<00000000633bd154>] tracing_map_init+0x1f8/0x268 [<000000007e814ab9>] event_hist_trigger_func+0xca0/0x1ad0 [<00000000bf8520ed>] trigger_process_regex+0xd4/0x128 [<00000000f549355a>] event_trigger_write+0x7c/0x120 [<00000000b80f898d>] vfs_write+0xc4/0x380 [<00000000823e1055>] ksys_write+0x74/0xf8 [<000000008a9374aa>] __arm64_sys_write+0x24/0x30 [<0000000087124017>] do_el0_svc+0x88/0x1c0 [<00000000efd0dcd1>] el0_svc+0x1c/0x28 [<00000000dbfba9b3>] el0_sync_handler+0x88/0xc0 [<00000000e7399680>] el0_sync+0x148/0x180 The reason is elts->pages[i] is alloced by get_zeroed_page. and kmemleak will not scan the area alloced by get_zeroed_page. The address stored in elts->pages will be regarded as leaked. That is, the elts->pages[i] will have pointers loaded onto it as well, and without telling kmemleak about it, those pointers will look like memory without a reference. To fix this, call kmemleak_alloc to tell kmemleak to scan elts->pages[i] Link: https://lkml.kernel.org/r/20211124140801.87121-1-chenjun102@huawei.com Signed-off-by: Chen Jun <chenjun102@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-12-01tracing/histograms: String compares should not care about signed valuesSteven Rostedt (VMware)
When comparing two strings for the "onmatch" histogram trigger, fields that are strings use string comparisons, which do not care about being signed or not. Do not fail to match two string fields if one is unsigned char array and the other is a signed char array. Link: https://lore.kernel.org/all/20211129123043.5cfd687a@gandalf.local.home/ Cc: stable@vgerk.kernel.org Cc: Tom Zanussi <zanussi@kernel.org> Cc: Yafang Shao <laoar.shao@gmail.com> Fixes: b05e89ae7cf3b ("tracing: Accept different type for synthetic event fields") Reviewed-by: Masami Hiramatsu <mhiramatsu@kernel.org> Reported-by: Sven Schnelle <svens@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-29block: remove the ->rq_disk field in struct requestChristoph Hellwig
Just use the disk attached to the request_queue instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20211126121802.2090656-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-27tracing: Test the 'Do not trace this pid' case in create eventSteven Rostedt (VMware)
When creating a new event (via a module, kprobe, eprobe, etc), the descriptors that are created must add flags for pid filtering if an instance has pid filtering enabled, as the flags are used at the time the event is executed to know if pid filtering should be done or not. The "Only trace this pid" case was added, but a cut and paste error made that case checked twice, instead of checking the "Trace all but this pid" case. Link: https://lore.kernel.org/all/202111280401.qC0z99JB-lkp@intel.com/ Fixes: 6cb206508b62 ("tracing: Check pid filtering when creating events") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-26tracing: Fix pid filtering when triggers are attachedSteven Rostedt (VMware)
If a event is filtered by pid and a trigger that requires processing of the event to happen is a attached to the event, the discard portion does not take the pid filtering into account, and the event will then be recorded when it should not have been. Cc: stable@vger.kernel.org Fixes: 3fdaf80f4a836 ("tracing: Implement event pid filtering") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ipa/ipa_main.c 8afc7e471ad3 ("net: ipa: separate disabling setup from modem stop") 76b5fbcd6b47 ("net: ipa: kill ipa_modem_init()") Duplicated include, drop one. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26tracing: Check pid filtering when creating eventsSteven Rostedt (VMware)
When pid filtering is activated in an instance, all of the events trace files for that instance has the PID_FILTER flag set. This determines whether or not pid filtering needs to be done on the event, otherwise the event is executed as normal. If pid filtering is enabled when an event is created (via a dynamic event or modules), its flag is not updated to reflect the current state, and the events are not filtered properly. Cc: stable@vger.kernel.org Fixes: 3fdaf80f4a836 ("tracing: Implement event pid filtering") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-23tracing/uprobe: Fix uprobe_perf_open probes iterationJiri Olsa
Add missing 'tu' variable initialization in the probes loop, otherwise the head 'tu' is used instead of added probes. Link: https://lkml.kernel.org/r/20211123142801.182530-1-jolsa@kernel.org Cc: stable@vger.kernel.org Fixes: 99c9a923e97a ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-19Merge tag 'trace-v5.16-6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Fix double free in destroy_hist_field - Harden memset() of trace_iterator structure - Do not warn in trace printk check when test buffer fills up * tag 'trace-v5.16-6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Don't use out-of-sync va_list in event printing tracing: Use memset_startat() to zero struct trace_iterator tracing/histogram: Fix UAF in destroy_hist_field()
2021-11-18tracing: Don't use out-of-sync va_list in event printingNikita Yushchenko
If trace_seq becomes full, trace_seq_vprintf() no longer consumes arguments from va_list, making va_list out of sync with format processing by trace_check_vprintf(). This causes va_arg() in trace_check_vprintf() to return wrong positional argument, which results into a WARN_ON_ONCE() hit. ftrace_stress_test from LTP triggers this situation. Fix it by explicitly avoiding further use if va_list at the point when it's consistency can no longer be guaranteed. Link: https://lkml.kernel.org/r/20211118145516.13219-1-nikita.yushchenko@virtuozzo.com Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-18tracing: Use memset_startat() to zero struct trace_iteratorKees Cook
In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memset(), avoid intentionally writing across neighboring fields. Use memset_startat() to avoid confusing memset() about writing beyond the target struct member. Link: https://lkml.kernel.org/r/20211118202217.1285588-1-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-18Merge tag 'net-5.16-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bpf, mac80211. Current release - regressions: - devlink: don't throw an error if flash notification sent before devlink visible - page_pool: Revert "page_pool: disable dma mapping support...", turns out there are active arches who need it Current release - new code bugs: - amt: cancel delayed_work synchronously in amt_fini() Previous releases - regressions: - xsk: fix crash on double free in buffer pool - bpf: fix inner map state pruning regression causing program rejections - mac80211: drop check for DONT_REORDER in __ieee80211_select_queue, preventing mis-selecting the best effort queue - mac80211: do not access the IV when it was stripped - mac80211: fix radiotap header generation, off-by-one - nl80211: fix getting radio statistics in survey dump - e100: fix device suspend/resume Previous releases - always broken: - tcp: fix uninitialized access in skb frags array for Rx 0cp - bpf: fix toctou on read-only map's constant scalar tracking - bpf: forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs - tipc: only accept encrypted MSG_CRYPTO msgs - smc: transfer remaining wait queue entries during fallback, fix missing wake ups - udp: validate checksum in udp_read_sock() (when sockmap is used) - sched: act_mirred: drop dst for the direction from egress to ingress - virtio_net_hdr_to_skb: count transport header in UFO, prevent allowing bad skbs into the stack - nfc: reorder the logic in nfc_{un,}register_device, fix unregister - ipsec: check return value of ipv6_skip_exthdr - usb: r8152: add MAC passthrough support for more Lenovo Docks" * tag 'net-5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (96 commits) ptp: ocp: Fix a couple NULL vs IS_ERR() checks net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock() net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound ipv6: check return value of ipv6_skip_exthdr e100: fix device suspend/resume devlink: Don't throw an error if flash notification sent before devlink visible page_pool: Revert "page_pool: disable dma mapping support..." ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port() octeontx2-af: debugfs: don't corrupt user memory NFC: add NCI_UNREG flag to eliminate the race NFC: reorder the logic in nfc_{un,}register_device NFC: reorganize the functions in nci_request tipc: check for null after calling kmemdup i40e: Fix display error code in dmesg i40e: Fix creation of first queue by omitting it if is not power of two i40e: Fix warning message and call stack during rmmod i40e driver i40e: Fix ping is lost after configuring ADq on VF i40e: Fix changing previously set num_queue_pairs for PFs i40e: Fix NULL ptr dereference on VSI filter sync i40e: Fix correct max_pkt_size on VF RX queue ...
2021-11-18tracing/histogram: Fix UAF in destroy_hist_field()Kalesh Singh
Calling destroy_hist_field() on an expression will recursively free any operands associated with the expression. If during expression parsing the operands of the expression are already set when an error is encountered, there is no need to explicity free the operands. Doing so will result in destroy_hist_field() being called twice for the operands and lead to a use-after-free (UAF) error. If the operands are associated with the expression, only call destroy_hist_field() on the expression since the operands will be recursively freed. Link: https://lore.kernel.org/all/CAHk-=wgcrEbFgkw9720H3tW-AhHOoEKhYwZinYJw4FpzSaJ6_Q@mail.gmail.com/ Link: https://lkml.kernel.org/r/20211118011542.1420131-1-kaleshsingh@google.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Fixes: 8b5d46fd7a38 ("tracing/histogram: Optimize division by constants") Reported-by: kernel test robot <oliver.sang@intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-15bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progsDmitrii Banshchikov
Use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in tracing progs may result in locking issues. bpf_ktime_get_coarse_ns() uses ktime_get_coarse_ns() time accessor that isn't safe for any context: ====================================================== WARNING: possible circular locking dependency detected 5.15.0-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.4/14877 is trying to acquire lock: ffffffff8cb30008 (tk_core.seq.seqcount){----}-{0:0}, at: ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255 but task is already holding lock: ffffffff90dbf200 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x61/0x400 lib/debugobjects.c:735 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&obj_hash[i].lock){-.-.}-{2:2}: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 __debug_object_init+0xd9/0x1860 lib/debugobjects.c:569 debug_hrtimer_init kernel/time/hrtimer.c:414 [inline] debug_init kernel/time/hrtimer.c:468 [inline] hrtimer_init+0x20/0x40 kernel/time/hrtimer.c:1592 ntp_init_cmos_sync kernel/time/ntp.c:676 [inline] ntp_init+0xa1/0xad kernel/time/ntp.c:1095 timekeeping_init+0x512/0x6bf kernel/time/timekeeping.c:1639 start_kernel+0x267/0x56e init/main.c:1030 secondary_startup_64_no_verify+0xb1/0xbb -> #0 (tk_core.seq.seqcount){----}-{0:0}: check_prev_add kernel/locking/lockdep.c:3051 [inline] check_prevs_add kernel/locking/lockdep.c:3174 [inline] validate_chain+0x1dfb/0x8240 kernel/locking/lockdep.c:3789 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5015 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5625 seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103 ktime_get_coarse_ts64+0x25/0x110 kernel/time/timekeeping.c:2255 ktime_get_coarse include/linux/timekeeping.h:120 [inline] ktime_get_coarse_ns include/linux/timekeeping.h:126 [inline] ____bpf_ktime_get_coarse_ns kernel/bpf/helpers.c:173 [inline] bpf_ktime_get_coarse_ns+0x7e/0x130 kernel/bpf/helpers.c:171 bpf_prog_a99735ebafdda2f1+0x10/0xb50 bpf_dispatcher_nop_func include/linux/bpf.h:721 [inline] __bpf_prog_run include/linux/filter.h:626 [inline] bpf_prog_run include/linux/filter.h:633 [inline] BPF_PROG_RUN_ARRAY include/linux/bpf.h:1294 [inline] trace_call_bpf+0x2cf/0x5d0 kernel/trace/bpf_trace.c:127 perf_trace_run_bpf_submit+0x7b/0x1d0 kernel/events/core.c:9708 perf_trace_lock+0x37c/0x440 include/trace/events/lock.h:39 trace_lock_release+0x128/0x150 include/trace/events/lock.h:58 lock_release+0x82/0x810 kernel/locking/lockdep.c:5636 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline] _raw_spin_unlock_irqrestore+0x75/0x130 kernel/locking/spinlock.c:194 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x2f9/0xa60 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x3b3/0x1040 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 try_to_wake_up+0x702/0xd20 kernel/sched/core.c:4118 wake_up_process kernel/sched/core.c:4200 [inline] wake_up_q+0x9a/0xf0 kernel/sched/core.c:953 futex_wake+0x50f/0x5b0 kernel/futex/waitwake.c:184 do_futex+0x367/0x560 kernel/futex/syscalls.c:127 __do_sys_futex kernel/futex/syscalls.c:199 [inline] __se_sys_futex+0x401/0x4b0 kernel/futex/syscalls.c:180 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae There is a possible deadlock with bpf_timer_* set of helpers: hrtimer_start() lock_base(); trace_hrtimer...() perf_event() bpf_run() bpf_timer_start() hrtimer_start() lock_base() <- DEADLOCK Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_* helpers in BPF_PROG_TYPE_KPROBE, BPF_PROG_TYPE_TRACEPOINT, BPF_PROG_TYPE_PERF_EVENT and BPF_PROG_TYPE_RAW_TRACEPOINT prog types. Fixes: d05512618056 ("bpf: Add bpf_ktime_get_coarse_ns helper") Fixes: b00628b1c7d5 ("bpf: Introduce bpf timers.") Reported-by: syzbot+43fd005b5a1b4d10781e@syzkaller.appspotmail.com Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211113142227.566439-2-me@ubique.spb.ru
2021-11-15Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Daniel Borkmann says: ==================== pull-request: bpf-next 2021-11-15 We've added 72 non-merge commits during the last 13 day(s) which contain a total of 171 files changed, 2728 insertions(+), 1143 deletions(-). The main changes are: 1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to BTF such that BPF verifier will be able to detect misuse, from Yonghong Song. 2) Big batch of libbpf improvements including various fixes, future proofing APIs, and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko. 3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush. 4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to ensure exception handling still works, from Russell King and Alan Maguire. 5) Add a new bpf_find_vma() helper for tracing to map an address to the backing file such as shared library, from Song Liu. 6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump, updating documentation and bash-completion among others, from Quentin Monnet. 7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as the API is heavily tailored around perf and is non-generic, from Dave Marchevsky. 8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an opt-out for more relaxed BPF program requirements, from Stanislav Fomichev. 9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits) bpftool: Use libbpf_get_error() to check error bpftool: Fix mixed indentation in documentation bpftool: Update the lists of names for maps and prog-attach types bpftool: Fix indent in option lists in the documentation bpftool: Remove inclusion of utilities.mak from Makefiles bpftool: Fix memory leak in prog_dump() selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning selftests/bpf: Fix an unused-but-set-variable compiler warning bpf: Introduce btf_tracing_ids bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs bpftool: Enable libbpf's strict mode by default docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support selftests/bpf: Clarify llvm dependency with btf_tag selftest selftests/bpf: Add a C test for btf_type_tag selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests selftests/bpf: Test libbpf API function btf__add_type_tag() bpftool: Support BTF_KIND_TYPE_TAG libbpf: Support BTF_KIND_TYPE_TAG ... ==================== Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-14Merge tag 'trace-v5.16-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fix from Steven Rostedt: "Update to tracing histogram variable string copy A fix to only copy the size of the field to the histogram string did not take into account that the size can be larger than the storage" * tag 'trace-v5.16-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Add length protection to histogram string copies
2021-11-14tracing: Add length protection to histogram string copiesSteven Rostedt (VMware)
The string copies to the histogram storage has a max size of 256 bytes (defined by MAX_FILTER_STR_VAL). Only the string size of the event field needs to be copied to the event storage, but no more than what is in the event storage. Although nothing should be bigger than 256 bytes, there's no protection against overwriting of the storage if one day there is. Copy no more than the destination size, and enforce it. Also had to turn MAX_FILTER_STR_VAL into an unsigned int, to keep the min() comparison of the string sizes of comparable types. Link: https://lore.kernel.org/all/CAHk-=wjREUihCGrtRBwfX47y_KrLCGjiq3t6QtoNJpmVrAEb1w@mail.gmail.com/ Link: https://lkml.kernel.org/r/20211114132834.183429a4@rorschach.local.home Cc: Ingo Molnar <mingo@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Tom Zanussi <zanussi@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Fixes: 63f84ae6b82b ("tracing/histogram: Do not copy the fixed-size char array field over the field size") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-13Merge tag 'trace-v5.16-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Three tracing fixes: - Make local osnoise_instances static - Copy just actual size of histogram strings - Properly check missing operands in histogram expressions" * tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/histogram: Fix check for missing operands in an expression tracing/histogram: Do not copy the fixed-size char array field over the field size tracing/osnoise: Make osnoise_instances static
2021-11-12tracing/histogram: Fix check for missing operands in an expressionKalesh Singh
If a binary operation is detected while parsing an expression string, the operand strings are deduced by splitting the experssion string at the position of the detected binary operator. Both operand strings are sub-strings (can be empty string) of the expression string but will never be NULL. Currently a NULL check is used for missing operands, fix this by checking for empty strings instead. Link: https://lkml.kernel.org/r/20211112191324.1302505-1-kaleshsingh@google.com Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Fixes: 9710b2f341a0 ("tracing: Fix operator precedence for hist triggers expression") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-12tracing/histogram: Do not copy the fixed-size char array field over the ↵Masami Hiramatsu
field size Do not copy the fixed-size char array field of the events over the field size. The histogram treats char array as a string and there are 2 types of char array in the event, fixed-size and dynamic string. The dynamic string (__data_loc) field must be null terminated, but the fixed-size char array field may not be null terminated (not a string, but just a data). In that case, histogram can copy the data after the field. This uses the original field size for fixed-size char array field to restrict the histogram not to access over the original field size. Link: https://lkml.kernel.org/r/163673292822.195747.3696966210526410250.stgit@devnote2 Fixes: 02205a6752f2 (tracing: Add support for 'field variables') Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-12bpf: Introduce btf_tracing_idsSong Liu
Similar to btf_sock_ids, btf_tracing_ids provides btf ID for task_struct, file, and vm_area_struct via easy to understand format like btf_tracing_ids[BTF_TRACING_TYPE_[TASK|file|VMA]]. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211112150243.1270987-3-songliubraving@fb.com
2021-11-12tracing/osnoise: Make osnoise_instances staticDaniel Bristot de Oliveira
Make the struct list_head osnoise_instances definition static. Link: https://lore.kernel.org/all/202111120052.ZuikQSJi-lkp@intel.com/ Link: https://lkml.kernel.org/r/d001f0eeac66e2b2eeec7d2a15e9e7abede0453a.1636667971.git.bristot@kernel.org Cc: Ingo Molnar <mingo@redhat.com> Fixes: dae181349f1e ("tracing/osnoise: Support a list of trace_array *tr") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-11Merge tag 'trace-v5.16-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Two locking fixes: - Add mutex protection to ring_buffer_reset() - Fix deadlock in modify_ftrace_direct_multi()" * tag 'trace-v5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/direct: Fix lockup in modify_ftrace_direct_multi ring-buffer: Protect ring_buffer_reset() from reentrancy
2021-11-10ftrace/direct: Fix lockup in modify_ftrace_direct_multiJiri Olsa
We can't call unregister_ftrace_function under ftrace_lock. Link: https://lkml.kernel.org/r/20211109114217.1645296-1-jolsa@kernel.org Fixes: ed29271894aa ("ftrace/direct: Do not disable when switching direct callers") Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-10ring-buffer: Protect ring_buffer_reset() from reentrancySteven Rostedt (VMware)
The resetting of the entire ring buffer use to simply go through and reset each individual CPU buffer that had its own protection and synchronization. But this was very slow, due to performing a synchronization for each CPU. The code was reshuffled to do one disabling of all CPU buffers, followed by a single RCU synchronization, and then the resetting of each of the CPU buffers. But unfortunately, the mutex that prevented multiple occurrences of resetting the buffer was not moved to the upper function, and there is nothing to protect from it. Take the ring buffer mutex around the global reset. Cc: stable@vger.kernel.org Fixes: b23d7a5f4a07a ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU") Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2021-11-09Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "87 patches. Subsystems affected by this patch series: mm (pagecache and hugetlb), procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs, init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork, sysvfs, kcov, gdb, resource, selftests, and ipc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits) ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL ipc: check checkpoint_restore_ns_capable() to modify C/R proc files selftests/kselftest/runner/run_one(): allow running non-executable files virtio-mem: disallow mapping virtio-mem memory via /dev/mem kernel/resource: disallow access to exclusive system RAM regions kernel/resource: clean up and optimize iomem_is_exclusive() scripts/gdb: handle split debug for vmlinux kcov: replace local_irq_save() with a local_lock_t kcov: avoid enable+disable interrupts if !in_task() kcov: allocate per-CPU memory on the relevant node Documentation/kcov: define `ip' in the example Documentation/kcov: include types.h in the example sysv: use BUILD_BUG_ON instead of runtime check kernel/fork.c: unshare(): use swap() to make code cleaner seq_file: fix passing wrong private data seq_file: move seq_escape() to a header signal: remove duplicate include in signal.h crash_dump: remove duplicate include in crash_dump.h crash_dump: fix boolreturn.cocci warning hfs/hfsplus: use WARN_ON for sanity check ...
2021-11-09sections: move and rename core_kernel_data() to is_kernel_core_data()Kefeng Wang
Move core_kernel_data() into sections.h and rename it to is_kernel_core_data(), also make it return bool value, then update all the callers. Link: https://lkml.kernel.org/r/20210930071143.63410-4-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexander Potapenko <glider@google.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Paul Mackerras <paulus@samba.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-07bpf: Introduce helper bpf_find_vmaSong Liu
In some profiler use cases, it is necessary to map an address to the backing file, e.g., a shared library. bpf_find_vma helper provides a flexible way to achieve this. bpf_find_vma maps an address of a task to the vma (vm_area_struct) for this address, and feed the vma to an callback BPF function. The callback function is necessary here, as we need to ensure mmap_sem is unlocked. It is necessary to lock mmap_sem for find_vma. To lock and unlock mmap_sem safely when irqs are disable, we use the same mechanism as stackmap with build_id. Specifically, when irqs are disabled, the unlocked is postponed in an irq_work. Refactor stackmap.c so that the irq_work is shared among bpf_find_vma and stackmap helpers. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Hengqi Chen <hengqi.chen@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211105232330.1936330-2-songliubraving@fb.com
2021-11-03Merge tag 'trace-v5.16-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: - osnoise and timerlat updates that will work with the RTLA tool (Real-Time Linux Analysis). Specifically it disconnects the work load (threads that look for latency) from the tracing instances attached to them, allowing for more than one instance to retrieve data from the work load. - Optimization on division in the trace histogram trigger code to use shift and multiply when possible. Also added documentation. - Fix prototype to my_direct_func in direct ftrace trampoline sample code. * tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace/samples: Add missing prototype for my_direct_func tracing/selftests: Add tests for hist trigger expression parsing tracing/histogram: Document hist trigger variables tracing/histogram: Update division by 0 documentation tracing/histogram: Optimize division by constants tracing/osnoise: Remove PREEMPT_RT ifdefs from inside functions tracing/osnoise: Remove STACKTRACE ifdefs from inside functions tracing/osnoise: Allow multiple instances of the same tracer tracing/osnoise: Remove TIMERLAT ifdefs from inside functions tracing/osnoise: Support a list of trace_array *tr tracing/osnoise: Use start/stop_per_cpu_kthreads() on osnoise_cpus_write() tracing/osnoise: Split workload start from the tracer start tracing/osnoise: Improve comments about barrier need for NMI callbacks tracing/osnoise: Do not follow tracing_cpumask
2021-11-02Merge tag 'net-next-for-5.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: "Core: - Remove socket skb caches - Add a SO_RESERVE_MEM socket op to forward allocate buffer space and avoid memory accounting overhead on each message sent - Introduce managed neighbor entries - added by control plane and resolved by the kernel for use in acceleration paths (BPF / XDP right now, HW offload users will benefit as well) - Make neighbor eviction on link down controllable by userspace to work around WiFi networks with bad roaming implementations - vrf: Rework interaction with netfilter/conntrack - fq_codel: implement L4S style ce_threshold_ect1 marking - sch: Eliminate unnecessary RCU waits in mini_qdisc_pair_swap() BPF: - Add support for new btf kind BTF_KIND_TAG, arbitrary type tagging as implemented in LLVM14 - Introduce bpf_get_branch_snapshot() to capture Last Branch Records - Implement variadic trace_printk helper - Add a new Bloomfilter map type - Track <8-byte scalar spill and refill - Access hw timestamp through BPF's __sk_buff - Disallow unprivileged BPF by default - Document BPF licensing Netfilter: - Introduce egress hook for looking at raw outgoing packets - Allow matching on and modifying inner headers / payload data - Add NFT_META_IFTYPE to match on the interface type either from ingress or egress Protocols: - Multi-Path TCP: - increase default max additional subflows to 2 - rework forward memory allocation - add getsockopts: MPTCP_INFO, MPTCP_TCPINFO, MPTCP_SUBFLOW_ADDRS - MCTP flow support allowing lower layer drivers to configure msg muxing as needed - Automatic Multicast Tunneling (AMT) driver based on RFC7450 - HSR support the redbox supervision frames (IEC-62439-3:2018) - Support for the ip6ip6 encapsulation of IOAM - Netlink interface for CAN-FD's Transmitter Delay Compensation - Support SMC-Rv2 eliminating the current same-subnet restriction, by exploiting the UDP encapsulation feature of RoCE adapters - TLS: add SM4 GCM/CCM crypto support - Bluetooth: initial support for link quality and audio/codec offload Driver APIs: - Add a batched interface for RX buffer allocation in AF_XDP buffer pool - ethtool: Add ability to control transceiver modules' power mode - phy: Introduce supported interfaces bitmap to express MAC capabilities and simplify PHY code - Drop rtnl_lock from DSA .port_fdb_{add,del} callbacks New drivers: - WiFi driver for Realtek 8852AE 802.11ax devices (rtw89) - Ethernet driver for ASIX AX88796C SPI device (x88796c) Drivers: - Broadcom PHYs - support 72165, 7712 16nm PHYs - support IDDQ-SR for additional power savings - PHY support for QCA8081, QCA9561 PHYs - NXP DPAA2: support for IRQ coalescing - NXP Ethernet (enetc): support for software TCP segmentation - Renesas Ethernet (ravb) - support DMAC and EMAC blocks of Gigabit-capable IP found on RZ/G2L SoC - Intel 100G Ethernet - support for eswitch offload of TC/OvS flow API, including offload of GRE, VxLAN, Geneve tunneling - support application device queues - ability to assign Rx and Tx queues to application threads - PTP and PPS (pulse-per-second) extensions - Broadcom Ethernet (bnxt) - devlink health reporting and device reload extensions - Mellanox Ethernet (mlx5) - offload macvlan interfaces - support HW offload of TC rules involving OVS internal ports - support HW-GRO and header/data split - support application device queues - Marvell OcteonTx2: - add XDP support for PF - add PTP support for VF - Qualcomm Ethernet switch (qca8k): support for QCA8328 - Realtek Ethernet DSA switch (rtl8366rb) - support bridge offload - support STP, fast aging, disabling address learning - support for Realtek RTL8365MB-VC, a 4+1 port 10M/100M/1GE switch - Mellanox Ethernet/IB switch (mlxsw) - multi-level qdisc hierarchy offload (e.g. RED, prio and shaping) - offload root TBF qdisc as port shaper - support multiple routing interface MAC address prefixes - support for IP-in-IP with IPv6 underlay - MediaTek WiFi (mt76) - mt7921 - ASPM, 6GHz, SDIO and testmode support - mt7915 - LED and TWT support - Qualcomm WiFi (ath11k) - include channel rx and tx time in survey dump statistics - support for 80P80 and 160 MHz bandwidths - support channel 2 in 6 GHz band - spectral scan support for QCN9074 - support for rx decapsulation offload (data frames in 802.3 format) - Qualcomm phone SoC WiFi (wcn36xx) - enable Idle Mode Power Save (IMPS) to reduce power consumption during idle - Bluetooth driver support for MediaTek MT7922 and MT7921 - Enable support for AOSP Bluetooth extension in Qualcomm WCN399x and Realtek 8822C/8852A - Microsoft vNIC driver (mana) - support hibernation and kexec - Google vNIC driver (gve) - support for jumbo frames - implement Rx page reuse Refactor: - Make all writes to netdev->dev_addr go thru helpers, so that we can add this address to the address rbtree and handle the updates - Various TCP cleanups and optimizations including improvements to CPU cache use - Simplify the gnet_stats, Qdisc stats' handling and remove qdisc->running sequence counter - Driver changes and API updates to address devlink locking deficiencies" * tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2122 commits) Revert "net: avoid double accounting for pure zerocopy skbs" selftests: net: add arp_ndisc_evict_nocarrier net: ndisc: introduce ndisc_evict_nocarrier sysctl parameter net: arp: introduce arp_evict_nocarrier sysctl parameter libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. net: vmxnet3: remove multiple false checks in vmxnet3_ethtool.c net: avoid double accounting for pure zerocopy skbs tcp: rename sk_wmem_free_skb netdevsim: fix uninit value in nsim_drv_configure_vfs() selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose ...
2021-11-01Merge tag 'trace-v5.16' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - kprobes: Restructured stack unwinder to show properly on x86 when a stack dump happens from a kretprobe callback. - Fix to bootconfig parsing - Have tracefs allow owner and group permissions by default (only denying others). There's been pressure to allow non root to tracefs in a controlled fashion, and using groups is probably the safest. - Bootconfig memory managament updates. - Bootconfig clean up to have the tools directory be less dependent on changes in the kernel tree. - Allow perf to be traced by function tracer. - Rewrite of function graph tracer to be a callback from the function tracer instead of having its own trampoline (this change will happen on an arch by arch basis, and currently only x86_64 implements it). - Allow multiple direct trampolines (bpf hooks to functions) be batched together in one synchronization. - Allow histogram triggers to add variables that can perform calculations against the event's fields. - Use the linker to determine architecture callbacks from the ftrace trampoline to allow for proper parameter prototypes and prevent warnings from the compiler. - Extend histogram triggers to key off of variables. - Have trace recursion use bit magic to determine preempt context over if branches. - Have trace recursion disable preemption as all use cases do anyway. - Added testing for verification of tracing utilities. - Various small clean ups and fixes. * tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits) tracing/histogram: Fix semicolon.cocci warnings tracing/histogram: Fix documentation inline emphasis warning tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together tracing: Show size of requested perf buffer bootconfig: Initialize ret in xbc_parse_tree() ftrace: do CPU checking after preemption disabled ftrace: disable preemption when recursion locked tracing/histogram: Document expression arithmetic and constants tracing/histogram: Optimize division by a power of 2 tracing/histogram: Covert expr to const if both operands are constants tracing/histogram: Simplify handling of .sym-offset in expressions tracing: Fix operator precedence for hist triggers expression tracing: Add division and multiplication support for hist triggers tracing: Add support for creating hist trigger variables from literal selftests/ftrace: Stop tracing while reading the trace file by default MAINTAINERS: Update KPROBES and TRACING entries test_kprobes: Move it from kernel/ to lib/ docs, kprobes: Remove invalid URL and add new reference samples/kretprobes: Fix return value if register_kretprobe() failed lib/bootconfig: Fix the xbc_get_info kerneldoc ...
2021-11-01Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-01tracing/histogram: Document hist trigger variablesKalesh Singh
Update the tracefs README to describe how hist trigger variables can be created. Link: https://lkml.kernel.org/r/20211029183339.3216491-4-kaleshsingh@google.com Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Kalesh Singh <kaleshsingh@google.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>