Commit Graph

2240 Commits

Author SHA1 Message Date
Linus Torvalds 7ebfc85e2c Including fixes from bluetooth, bpf, can and netfilter.
A little longer PR than usual but it's all fixes, no late features.
 It's long partially because of timing, and partially because of
 follow ups to stuff that got merged a week or so before the merge
 window and wasn't as widely tested. Maybe the Bluetooth fixes are
 a little alarming so we'll address that, but the rest seems okay
 and not scary.
 
 Notably we're including a fix for the netfilter Kconfig [1], your
 WiFi warning [2] and a bluetooth fix which should unblock syzbot [3].
 
 Current release - regressions:
 
  - Bluetooth:
    - don't try to cancel uninitialized works [3]
    - L2CAP: fix use-after-free caused by l2cap_chan_put
 
  - tls: rx: fix device offload after recent rework
 
  - devlink: fix UAF on failed reload and leftover locks in mlxsw
 
 Current release - new code bugs:
 
  - netfilter:
    - flowtable: fix incorrect Kconfig dependencies [1]
    - nf_tables: fix crash when nf_trace is enabled
 
  - bpf:
    - use proper target btf when exporting attach_btf_obj_id
    - arm64: fixes for bpf trampoline support
 
  - Bluetooth:
    - ISO: unlock on error path in iso_sock_setsockopt()
    - ISO: fix info leak in iso_sock_getsockopt()
    - ISO: fix iso_sock_getsockopt for BT_DEFER_SETUP
    - ISO: fix memory corruption on iso_pinfo.base
    - ISO: fix not using the correct QoS
    - hci_conn: fix updating ISO QoS PHY
 
  - phy: dp83867: fix get nvmem cell fail
 
 Previous releases - regressions:
 
  - wifi: cfg80211: fix validating BSS pointers in
    __cfg80211_connect_result [2]
 
  - atm: bring back zatm uAPI after ATM had been removed
 
  - properly fix old bug making bonding ARP monitor mode not being
    able to work with software devices with lockless Tx
 
  - tap: fix null-deref on skb->dev in dev_parse_header_protocol
 
  - revert "net: usb: ax88179_178a needs FLAG_SEND_ZLP" it helps
    some devices and breaks others
 
  - netfilter:
    - nf_tables: many fixes rejecting cross-object linking
      which may lead to UAFs
    - nf_tables: fix null deref due to zeroed list head
    - nf_tables: validate variable length element extension
 
  - bgmac: fix a BUG triggered by wrong bytes_compl
 
  - bcmgenet: indicate MAC is in charge of PHY PM
 
 Previous releases - always broken:
 
  - bpf:
    - fix bad pointer deref in bpf_sys_bpf() injected via test infra
    - disallow non-builtin bpf programs calling the prog_run command
    - don't reinit map value in prealloc_lru_pop
    - fix UAFs during the read of map iterator fd
    - fix invalidity check for values in sk local storage map
    - reject sleepable program for non-resched map iterator
 
  - mptcp:
    - move subflow cleanup in mptcp_destroy_common()
    - do not queue data on closed subflows
 
  - virtio_net: fix memory leak inside XDP_TX with mergeable
 
  - vsock: fix memory leak when multiple threads try to connect()
 
  - rework sk_user_data sharing to prevent psock leaks
 
  - geneve: fix TOS inheriting for ipv4
 
  - tunnels & drivers: do not use RT_TOS for IPv6 flowlabel
 
  - phy: c45 baset1: do not skip aneg configuration if clock role
    is not specified
 
  - rose: avoid overflow when /proc displays timer information
 
  - x25: fix call timeouts in blocking connects
 
  - can: mcp251x: fix race condition on receive interrupt
 
  - can: j1939:
    - replace user-reachable WARN_ON_ONCE() with netdev_warn_once()
    - fix memory leak of skbs in j1939_session_destroy()
 
 Misc:
 
  - docs: bpf: clarify that many things are not uAPI
 
  - seg6: initialize induction variable to first valid array index
    (to silence clang vs objtool warning)
 
  - can: ems_usb: fix clang 14's -Wunaligned-access warning
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bluetooth, bpf, can and netfilter.

  A little larger than usual but it's all fixes, no late features. It's
  large partially because of timing, and partially because of follow ups
  to stuff that got merged a week or so before the merge window and
  wasn't as widely tested. Maybe the Bluetooth fixes are a little
  alarming so we'll address that, but the rest seems okay and not scary.

  Notably we're including a fix for the netfilter Kconfig [1], your WiFi
  warning [2] and a bluetooth fix which should unblock syzbot [3].

  Current release - regressions:

   - Bluetooth:
      - don't try to cancel uninitialized works [3]
      - L2CAP: fix use-after-free caused by l2cap_chan_put

   - tls: rx: fix device offload after recent rework

   - devlink: fix UAF on failed reload and leftover locks in mlxsw

  Current release - new code bugs:

   - netfilter:
      - flowtable: fix incorrect Kconfig dependencies [1]
      - nf_tables: fix crash when nf_trace is enabled

   - bpf:
      - use proper target btf when exporting attach_btf_obj_id
      - arm64: fixes for bpf trampoline support

   - Bluetooth:
      - ISO: unlock on error path in iso_sock_setsockopt()
      - ISO: fix info leak in iso_sock_getsockopt()
      - ISO: fix iso_sock_getsockopt for BT_DEFER_SETUP
      - ISO: fix memory corruption on iso_pinfo.base
      - ISO: fix not using the correct QoS
      - hci_conn: fix updating ISO QoS PHY

   - phy: dp83867: fix get nvmem cell fail

  Previous releases - regressions:

   - wifi: cfg80211: fix validating BSS pointers in
     __cfg80211_connect_result [2]

   - atm: bring back zatm uAPI after ATM had been removed

   - properly fix old bug making bonding ARP monitor mode not being able
     to work with software devices with lockless Tx

   - tap: fix null-deref on skb->dev in dev_parse_header_protocol

   - revert "net: usb: ax88179_178a needs FLAG_SEND_ZLP" it helps some
     devices and breaks others

   - netfilter:
      - nf_tables: many fixes rejecting cross-object linking which may
        lead to UAFs
      - nf_tables: fix null deref due to zeroed list head
      - nf_tables: validate variable length element extension

   - bgmac: fix a BUG triggered by wrong bytes_compl

   - bcmgenet: indicate MAC is in charge of PHY PM

  Previous releases - always broken:

   - bpf:
      - fix bad pointer deref in bpf_sys_bpf() injected via test infra
      - disallow non-builtin bpf programs calling the prog_run command
      - don't reinit map value in prealloc_lru_pop
      - fix UAFs during the read of map iterator fd
      - fix invalidity check for values in sk local storage map
      - reject sleepable program for non-resched map iterator

   - mptcp:
      - move subflow cleanup in mptcp_destroy_common()
      - do not queue data on closed subflows

   - virtio_net: fix memory leak inside XDP_TX with mergeable

   - vsock: fix memory leak when multiple threads try to connect()

   - rework sk_user_data sharing to prevent psock leaks

   - geneve: fix TOS inheriting for ipv4

   - tunnels & drivers: do not use RT_TOS for IPv6 flowlabel

   - phy: c45 baset1: do not skip aneg configuration if clock role is
     not specified

   - rose: avoid overflow when /proc displays timer information

   - x25: fix call timeouts in blocking connects

   - can: mcp251x: fix race condition on receive interrupt

   - can: j1939:
      - replace user-reachable WARN_ON_ONCE() with netdev_warn_once()
      - fix memory leak of skbs in j1939_session_destroy()

  Misc:

   - docs: bpf: clarify that many things are not uAPI

   - seg6: initialize induction variable to first valid array index (to
     silence clang vs objtool warning)

   - can: ems_usb: fix clang 14's -Wunaligned-access warning"

* tag 'net-6.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (117 commits)
  net: atm: bring back zatm uAPI
  dpaa2-eth: trace the allocated address instead of page struct
  net: add missing kdoc for struct genl_multicast_group::flags
  nfp: fix use-after-free in area_cache_get()
  MAINTAINERS: use my korg address for mt7601u
  mlxsw: minimal: Fix deadlock in ports creation
  bonding: fix reference count leak in balance-alb mode
  net: usb: qmi_wwan: Add support for Cinterion MV32
  bpf: Shut up kern_sys_bpf warning.
  net/tls: Use RCU API to access tls_ctx->netdev
  tls: rx: device: don't try to copy too much on detach
  tls: rx: device: bound the frag walk
  net_sched: cls_route: remove from list when handle is 0
  selftests: forwarding: Fix failing tests with old libnet
  net: refactor bpf_sk_reuseport_detach()
  net: fix refcount bug in sk_psock_get (2)
  selftests/bpf: Ensure sleepable program is rejected by hash map iter
  selftests/bpf: Add write tests for sk local storage map iterator
  selftests/bpf: Add tests for reading a dangling map iter fd
  bpf: Only allow sleepable program for resched-able iterator
  ...
2022-08-11 13:45:37 -07:00
Alexei Starovoitov 86f44fcec2 bpf: Disallow bpf programs call prog_run command.
The verifier cannot perform sufficient validation of bpf_attr->test.ctx_in
pointer, therefore bpf programs should not be allowed to call BPF_PROG_RUN
command from within the program.
To fix this issue split bpf_sys_bpf() bpf helper into normal kern_sys_bpf()
kernel function that can only be used by the kernel light skeleton directly.

Reported-by: YiFei Zhu <zhuyifei@google.com>
Fixes: b1d18a7574 ("bpf: Extend sys_bpf commands for bpf_syscall programs.")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-08-10 09:43:07 -07:00
Linus Torvalds 4e23eeebb2 Bitmap patches for v6.0-rc1
This branch consists of:
 
 Qu Wenruo:
 lib: bitmap: fix the duplicated comments on bitmap_to_arr64()
 https://lore.kernel.org/lkml/0d85e1dbad52ad7fb5787c4432bdb36cbd24f632.1656063005.git.wqu@suse.com/
 
 Alexander Lobakin:
 bitops: let optimize out non-atomic bitops on compile-time constants
 https://lore.kernel.org/lkml/20220624121313.2382500-1-alexandr.lobakin@intel.com/T/
 
 Yury Norov:
 lib: cleanup bitmap-related headers
 https://lore.kernel.org/linux-arm-kernel/YtCVeOGLiQ4gNPSf@yury-laptop/T/#m305522194c4d38edfdaffa71fcaaf2e2ca00a961
 
 Alexander Lobakin:
 x86/olpc: fix 'logical not is only applied to the left hand side'
 https://www.spinics.net/lists/kernel/msg4440064.html
 
 Yury Norov:
 lib/nodemask: inline wrappers around bitmap
 https://lore.kernel.org/all/20220723214537.2054208-1-yury.norov@gmail.com/
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Merge tag 'bitmap-6.0-rc1' of https://github.com/norov/linux

Pull bitmap updates from Yury Norov:

 - fix the duplicated comments on bitmap_to_arr64() (Qu Wenruo)

 - optimize out non-atomic bitops on compile-time constants (Alexander
   Lobakin)

 - cleanup bitmap-related headers (Yury Norov)

 - x86/olpc: fix 'logical not is only applied to the left hand side'
   (Alexander Lobakin)

 - lib/nodemask: inline wrappers around bitmap (Yury Norov)

* tag 'bitmap-6.0-rc1' of https://github.com/norov/linux: (26 commits)
  lib/nodemask: inline next_node_in() and node_random()
  powerpc: drop dependency on <asm/machdep.h> in archrandom.h
  x86/olpc: fix 'logical not is only applied to the left hand side'
  lib/cpumask: move some one-line wrappers to header file
  headers/deps: mm: align MANITAINERS and Docs with new gfp.h structure
  headers/deps: mm: Split <linux/gfp_types.h> out of <linux/gfp.h>
  headers/deps: mm: Optimize <linux/gfp.h> header dependencies
  lib/cpumask: move trivial wrappers around find_bit to the header
  lib/cpumask: change return types to unsigned where appropriate
  cpumask: change return types to bool where appropriate
  lib/bitmap: change type of bitmap_weight to unsigned long
  lib/bitmap: change return types to bool where appropriate
  arm: align find_bit declarations with generic kernel
  iommu/vt-d: avoid invalid memory access via node_online(NUMA_NO_NODE)
  lib/test_bitmap: test the tail after bitmap_to_arr64()
  lib/bitmap: fix off-by-one in bitmap_to_arr64()
  lib: test_bitmap: add compile-time optimization/evaluations assertions
  bitmap: don't assume compiler evaluates small mem*() builtins calls
  net/ice: fix initializing the bitmap in the switch code
  bitops: let optimize out non-atomic bitops on compile-time constants
  ...
2022-08-07 17:52:35 -07:00
Linus Torvalds 48a577dc1b perf tools changes for v6.0: 1st batch
- Introduce 'perf lock contention' subtool, using new lock contention
   tracepoints and using BPF for in kernel aggregation and then userspace
   processing using the perf tooling infrastructure for resolving symbols, target
   specification, etc.
 
   Since the new lock contention tracepoints don't provide lock names, get up to
   8 stack traces and display the first non-lock function symbol name as a caller:
 
   $ perf lock report -F acquired,contended,avg_wait,wait_total
 
                   Name   acquired  contended     avg wait    total wait
 
    update_blocked_a...         40         40      3.61 us     144.45 us
    kernfs_fop_open+...          5          5      3.64 us      18.18 us
     _nohz_idle_balance          3          3      2.65 us       7.95 us
    tick_do_update_j...          1          1      6.04 us       6.04 us
     ep_scan_ready_list          1          1      3.93 us       3.93 us
 
   Supports the usual 'perf record' + 'perf report' workflow as well as a
   BCC/bpftrace like mode where you start the tool and then press control+C to get
   results:
 
    $ sudo perf lock contention -b
   ^C
    contended   total wait     max wait     avg wait         type   caller
 
           42    192.67 us     13.64 us      4.59 us     spinlock   queue_work_on+0x20
           23     85.54 us     10.28 us      3.72 us     spinlock   worker_thread+0x14a
            6     13.92 us      6.51 us      2.32 us        mutex   kernfs_iop_permission+0x30
            3     11.59 us     10.04 us      3.86 us        mutex   kernfs_dop_revalidate+0x3c
            1      7.52 us      7.52 us      7.52 us     spinlock   kthread+0x115
            1      7.24 us      7.24 us      7.24 us     rwlock:W   sys_epoll_wait+0x148
            2      7.08 us      3.99 us      3.54 us     spinlock   delayed_work_timer_fn+0x1b
            1      6.41 us      6.41 us      6.41 us     spinlock   idle_balance+0xa06
            2      2.50 us      1.83 us      1.25 us        mutex   kernfs_iop_lookup+0x2f
            1      1.71 us      1.71 us      1.71 us        mutex   kernfs_iop_getattr+0x2c
   ...
 
 - Add new 'perf kwork' tool to trace time properties of kernel work (such as
   softirq, and workqueue), uses eBPF skeletons to collect info in kernel space,
   aggregating data that then gets processed by the userspace tool, e.g.:
 
   # perf kwork report
 
    Kwork Name      | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
   ----------------------------------------------------------------------------------------------------
    nvme0q5:130     | 004 |      1.101 ms |    49 |    0.051 ms |    26035.056403 s |  26035.056455 s |
    amdgpu:162      | 002 |      0.176 ms |     9 |    0.046 ms |    26035.268020 s |  26035.268066 s |
    nvme0q24:149    | 023 |      0.161 ms |    55 |    0.009 ms |    26035.655280 s |  26035.655288 s |
    nvme0q20:145    | 019 |      0.090 ms |    33 |    0.014 ms |    26035.939018 s |  26035.939032 s |
    nvme0q31:156    | 030 |      0.075 ms |    21 |    0.010 ms |    26035.052237 s |  26035.052247 s |
    nvme0q8:133     | 007 |      0.062 ms |    12 |    0.021 ms |    26035.416840 s |  26035.416861 s |
    nvme0q6:131     | 005 |      0.054 ms |    22 |    0.010 ms |    26035.199919 s |  26035.199929 s |
    nvme0q19:144    | 018 |      0.052 ms |    14 |    0.010 ms |    26035.110615 s |  26035.110625 s |
    nvme0q7:132     | 006 |      0.049 ms |    13 |    0.007 ms |    26035.125180 s |  26035.125187 s |
    nvme0q18:143    | 017 |      0.033 ms |    14 |    0.007 ms |    26035.169698 s |  26035.169705 s |
    nvme0q17:142    | 016 |      0.013 ms |     1 |    0.013 ms |    26035.565147 s |  26035.565160 s |
    enp5s0-rx-0:164 | 006 |      0.004 ms |     4 |    0.002 ms |    26035.928882 s |  26035.928884 s |
    enp5s0-tx-0:166 | 008 |      0.003 ms |     3 |    0.002 ms |    26035.870923 s |  26035.870925 s |
   --------------------------------------------------------------------------------------------------------
 
   See commit log messages for more examples with extra options to limit the events time window, etc.
 
 - Add support for new AMD IBS (Instruction Based Sampling) features:
 
   With the DataSrc extensions, the source of data can be decoded among:
  - Local L3 or other L1/L2 in CCX.
  - A peer cache in a near CCX.
  - Data returned from DRAM.
  - A peer cache in a far CCX.
  - DRAM address map with "long latency" bit set.
  - Data returned from MMIO/Config/PCI/APIC.
  - Extension Memory (S-Link, GenZ, etc - identified by the CS target
     and/or address map at DF's choice).
  - Peer Agent Memory.
 
 - Support hardware tracing with Intel PT on guest machines, combining the
   traces with the ones in the host machine.
 
 - Add a "-m" option to 'perf buildid-list' to show kernel and modules
   build-ids, to display all of the information needed to do external
   symbolization of kernel stack traces, such as those collected by
   bpf_get_stackid().
 
 - Add arch TSC frequency information to perf.data file headers.
 
 - Handle changes in the binutils disassembler function signatures in
   perf, bpftool and bpf_jit_disasm (Acked by the bpftool maintainer).
 
 - Fix building the perf perl binding with the newest gcc in distros such
   as fedora rawhide, where some new warnings were breaking the build as
   perf uses -Werror.
 
 - Add 'perf test' entry for branch stack sampling.
 
 - Add ARM SPE system wide 'perf test' entry.
 
 - Add user space counter reading tests to 'perf test'.
 
 - Build with python3 by default, if available.
 
 - Add python converter script for the vendor JSON event files.
 
 - Update vendor JSON files for alderlake, bonnell, broadwell, broadwellde,
   broadwellx, cascadelakex, elkhartlake, goldmont, goldmontplus, haswell,
   haswellx, icelake, icelakex, ivybridge, ivytown, jaketown, knightslanding,
   nehalemep, nehalemex, sandybridge, sapphirerapids, silvermont, skylake,
   skylakex, snowridgex, tigerlake, westmereep-dp, westmereep-sp and westmereex.
 
 - Add vendor JSON File for Intel meteorlake.
 
 - Add Arm Cortex-A78C and X1C JSON vendor event files.
 
 - Add workaround to symbol address reading from ELF files without phdr,
   falling back to the previoous equation.
 
 - Convert legacy map definition to BTF-defined in the perf BPF script test.
 
 - Rework prologue generation code to stop using libbpf deprecated APIs.
 
 - Add default hybrid events for 'perf stat' on x86.
 
 - Add topdown metrics in the default 'perf stat' on the hybrid machines (big/little cores).
 
 - Prefer sampled CPU when exporting JSON in 'perf data convert'
 
 - Fix ('perf stat CSV output linter') and ("Check branch stack sampling") 'perf test' entries on s390.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tools updates from Arnaldo Carvalho de Melo:

 - Introduce 'perf lock contention' subtool, using new lock contention
   tracepoints and using BPF for in kernel aggregation and then
   userspace processing using the perf tooling infrastructure for
   resolving symbols, target specification, etc.

   Since the new lock contention tracepoints don't provide lock names,
   get up to 8 stack traces and display the first non-lock function
   symbol name as a caller:

    $ perf lock report -F acquired,contended,avg_wait,wait_total

                    Name   acquired  contended     avg wait    total wait

     update_blocked_a...         40         40      3.61 us     144.45 us
     kernfs_fop_open+...          5          5      3.64 us      18.18 us
      _nohz_idle_balance          3          3      2.65 us       7.95 us
     tick_do_update_j...          1          1      6.04 us       6.04 us
      ep_scan_ready_list          1          1      3.93 us       3.93 us

   Supports the usual 'perf record' + 'perf report' workflow as well as
   a BCC/bpftrace like mode where you start the tool and then press
   control+C to get results:

     $ sudo perf lock contention -b
    ^C
    contended   total wait     max wait     avg wait         type   caller

            42    192.67 us     13.64 us      4.59 us     spinlock   queue_work_on+0x20
            23     85.54 us     10.28 us      3.72 us     spinlock   worker_thread+0x14a
             6     13.92 us      6.51 us      2.32 us        mutex   kernfs_iop_permission+0x30
             3     11.59 us     10.04 us      3.86 us        mutex   kernfs_dop_revalidate+0x3c
             1      7.52 us      7.52 us      7.52 us     spinlock   kthread+0x115
             1      7.24 us      7.24 us      7.24 us     rwlock:W   sys_epoll_wait+0x148
             2      7.08 us      3.99 us      3.54 us     spinlock   delayed_work_timer_fn+0x1b
             1      6.41 us      6.41 us      6.41 us     spinlock   idle_balance+0xa06
             2      2.50 us      1.83 us      1.25 us        mutex   kernfs_iop_lookup+0x2f
             1      1.71 us      1.71 us      1.71 us        mutex   kernfs_iop_getattr+0x2c
    ...

 - Add new 'perf kwork' tool to trace time properties of kernel work
   (such as softirq, and workqueue), uses eBPF skeletons to collect info
   in kernel space, aggregating data that then gets processed by the
   userspace tool, e.g.:

    # perf kwork report

     Kwork Name      | Cpu | Total Runtime | Count | Max runtime | Max runtime start | Max runtime end |
    ----------------------------------------------------------------------------------------------------
     nvme0q5:130     | 004 |      1.101 ms |    49 |    0.051 ms |    26035.056403 s |  26035.056455 s |
     amdgpu:162      | 002 |      0.176 ms |     9 |    0.046 ms |    26035.268020 s |  26035.268066 s |
     nvme0q24:149    | 023 |      0.161 ms |    55 |    0.009 ms |    26035.655280 s |  26035.655288 s |
     nvme0q20:145    | 019 |      0.090 ms |    33 |    0.014 ms |    26035.939018 s |  26035.939032 s |
     nvme0q31:156    | 030 |      0.075 ms |    21 |    0.010 ms |    26035.052237 s |  26035.052247 s |
     nvme0q8:133     | 007 |      0.062 ms |    12 |    0.021 ms |    26035.416840 s |  26035.416861 s |
     nvme0q6:131     | 005 |      0.054 ms |    22 |    0.010 ms |    26035.199919 s |  26035.199929 s |
     nvme0q19:144    | 018 |      0.052 ms |    14 |    0.010 ms |    26035.110615 s |  26035.110625 s |
     nvme0q7:132     | 006 |      0.049 ms |    13 |    0.007 ms |    26035.125180 s |  26035.125187 s |
     nvme0q18:143    | 017 |      0.033 ms |    14 |    0.007 ms |    26035.169698 s |  26035.169705 s |
     nvme0q17:142    | 016 |      0.013 ms |     1 |    0.013 ms |    26035.565147 s |  26035.565160 s |
     enp5s0-rx-0:164 | 006 |      0.004 ms |     4 |    0.002 ms |    26035.928882 s |  26035.928884 s |
     enp5s0-tx-0:166 | 008 |      0.003 ms |     3 |    0.002 ms |    26035.870923 s |  26035.870925 s |
    --------------------------------------------------------------------------------------------------------

   See commit log messages for more examples with extra options to limit
   the events time window, etc.

 - Add support for new AMD IBS (Instruction Based Sampling) features:

   With the DataSrc extensions, the source of data can be decoded among:
     - Local L3 or other L1/L2 in CCX.
     - A peer cache in a near CCX.
     - Data returned from DRAM.
     - A peer cache in a far CCX.
     - DRAM address map with "long latency" bit set.
     - Data returned from MMIO/Config/PCI/APIC.
     - Extension Memory (S-Link, GenZ, etc - identified by the CS target
       and/or address map at DF's choice).
     - Peer Agent Memory.

 - Support hardware tracing with Intel PT on guest machines, combining
   the traces with the ones in the host machine.

 - Add a "-m" option to 'perf buildid-list' to show kernel and modules
   build-ids, to display all of the information needed to do external
   symbolization of kernel stack traces, such as those collected by
   bpf_get_stackid().

 - Add arch TSC frequency information to perf.data file headers.

 - Handle changes in the binutils disassembler function signatures in
   perf, bpftool and bpf_jit_disasm (Acked by the bpftool maintainer).

 - Fix building the perf perl binding with the newest gcc in distros
   such as fedora rawhide, where some new warnings were breaking the
   build as perf uses -Werror.

 - Add 'perf test' entry for branch stack sampling.

 - Add ARM SPE system wide 'perf test' entry.

 - Add user space counter reading tests to 'perf test'.

 - Build with python3 by default, if available.

 - Add python converter script for the vendor JSON event files.

 - Update vendor JSON files for most Intel cores.

 - Add vendor JSON File for Intel meteorlake.

 - Add Arm Cortex-A78C and X1C JSON vendor event files.

 - Add workaround to symbol address reading from ELF files without phdr,
   falling back to the previoous equation.

 - Convert legacy map definition to BTF-defined in the perf BPF script
   test.

 - Rework prologue generation code to stop using libbpf deprecated APIs.

 - Add default hybrid events for 'perf stat' on x86.

 - Add topdown metrics in the default 'perf stat' on the hybrid machines
   (big/little cores).

 - Prefer sampled CPU when exporting JSON in 'perf data convert'

 - Fix ('perf stat CSV output linter') and ("Check branch stack
   sampling") 'perf test' entries on s390.

* tag 'perf-tools-for-v6.0-2022-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (169 commits)
  perf stat: Refactor __run_perf_stat() common code
  perf lock: Print the number of lost entries for BPF
  perf lock: Add --map-nr-entries option
  perf lock: Introduce struct lock_contention
  perf scripting python: Do not build fail on deprecation warnings
  genelf: Use HAVE_LIBCRYPTO_SUPPORT, not the never defined HAVE_LIBCRYPTO
  perf build: Suppress openssl v3 deprecation warnings in libcrypto feature test
  perf parse-events: Break out tracepoint and printing
  perf parse-events: Don't #define YY_EXTRA_TYPE
  tools bpftool: Don't display disassembler-four-args feature test
  tools bpftool: Fix compilation error with new binutils
  tools bpf_jit_disasm: Don't display disassembler-four-args feature test
  tools bpf_jit_disasm: Fix compilation error with new binutils
  tools perf: Fix compilation error with new binutils
  tools include: add dis-asm-compat.h to handle version differences
  tools build: Don't display disassembler-four-args feature test
  tools build: Add feature test for init_disassemble_info API changes
  perf test: Add ARM SPE system wide test
  perf tools: Rework prologue generation code
  perf bpf: Convert legacy map definition to BTF-defined
  ...
2022-08-06 09:36:08 -07:00
Joe Burton 395fc4fa33 libbpf: Add bpf_obj_get_opts()
Add an extensible variant of bpf_obj_get() capable of setting the
`file_flags` parameter.

This parameter is needed to enable unprivileged access to BPF maps.
Without a method like this, users must manually make the syscall.

Signed-off-by: Joe Burton <jevburton@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220729202727.3311806-1-jevburton.kernel@gmail.com
2022-07-29 15:30:06 -07:00
Daniel Müller 64893e83f9 libbpf: Support PPC in arch_specific_syscall_pfx
Commit 708ac5bea0 ("libbpf: add ksyscall/kretsyscall sections support
for syscall kprobes") added the arch_specific_syscall_pfx() function,
which returns a string representing the architecture in use. As it turns
out this function is currently not aware of Power PC, where NULL is
returned. That's being flagged by the libbpf CI system, which builds for
ppc64le and the compiler sees a NULL pointer being passed in to a %s
format string.
With this change we add representations for two more architectures, for
Power PC and Power PC 64, and also adjust the string format logic to
handle NULL pointers gracefully, in an attempt to prevent similar issues
with other architectures in the future.

Fixes: 708ac5bea0 ("libbpf: add ksyscall/kretsyscall sections support for syscall kprobes")
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220728222345.3125975-1-deso@posteo.net
2022-07-28 16:11:18 -07:00
Ilya Leoshkevich 2d369b4b00 libbpf: Extend BPF_KSYSCALL documentation
Explicitly list known quirks. Mention that socket-related syscalls can be
invoked via socketcall().

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20220726134008.256968-2-iii@linux.ibm.com
2022-07-26 16:27:21 +02:00
Dan Carpenter 14229b8153 libbpf: Fix str_has_sfx()'s return value
The return from strcmp() is inverted so it wrongly returns true instead
of false and vice versa.

Fixes: a1c9d61b19 ("libbpf: Improve library identification for uprobe binary path resolution")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Cc: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/YtZ+/dAA195d99ak@kili
2022-07-21 14:30:25 +02:00
Dan Carpenter c6018fc6e7 libbpf: Fix sign expansion bug in btf_dump_get_enum_value()
The code here is supposed to take a signed int and store it in a signed
long long. Unfortunately, the way that the type promotion works with
this conditional statement is that it takes a signed int, type promotes
it to a __u32, and then stores that as a signed long long. The result is
never negative.

This is from static analysis, but I made a little test program just to
test it before I sent the patch:

  #include <stdio.h>

  int main(void)
  {
        unsigned long long src = -1ULL;
        signed long long dst1, dst2;
        int is_signed = 1;

        dst1 = is_signed ? *(int *)&src : *(unsigned int *)0;
        dst2 = is_signed ? (signed long long)*(int *)&src : *(unsigned int *)0;

        printf("%lld\n", dst1);
        printf("%lld\n", dst2);

        return 0;
  }

Fixes: d90ec262b3 ("libbpf: Add enum64 support for btf_dump")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/YtZ+LpgPADm7BeEd@kili
2022-07-21 14:24:18 +02:00
Adrian Hunter 7151c1d178 perf auxtrace: Add machine_pid and vcpu to auxtrace_error
Add machine_pid and vcpu to struct perf_record_auxtrace_error. The existing
fmt member is used to identify the new format.

The new members make it possible to easily differentiate errors from guest
machines.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-18-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-07-20 11:08:17 -03:00
Adrian Hunter b47bb18661 perf tools: Add machine_pid and vcpu to id_index
When injecting events from a guest perf.data file, the events will have
separate sample ID numbers. These ID numbers can then be used to determine
which machine an event belongs to. To facilitate that, add machine_pid and
vcpu to id_index records. For backward compatibility, these are added at
the end of the record, and the length of the record is used to determine
if they are present or not.

Note, this is needed because the events from a guest perf.data file contain
the pid/tid of the process running at that time inside the VM not the
pid/tid of the (QEMU) hypervisor thread. So a way is needed to relate
guest events back to the guest machine and VCPU, and using sample ID
numbers for that is relatively simple and convenient.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20220711093218.10967-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-07-20 11:07:58 -03:00
Dan Carpenter b77ffb30cf libbpf: fix an snprintf() overflow check
The snprintf() function returns the number of bytes it *would* have
copied if there were enough space.  So it can return > the
sizeof(gen->attach_target).

Fixes: 6723474373 ("libbpf: Generate loader program out of BPF ELF file.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/YtZ+oAySqIhFl6/J@kili
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 10:47:31 -07:00
Andrii Nakryiko 597fbc4682 libbpf: make RINGBUF map size adjustments more eagerly
Make libbpf adjust RINGBUF map size (rounding it up to closest power-of-2
of page_size) more eagerly: during open phase when initializing the map
and on explicit calls to bpf_map__set_max_entries().

Such approach allows user to check actual size of BPF ringbuf even
before it's created in the kernel, but also it prevents various edge
case scenarios where BPF ringbuf size can get out of sync with what it
would be in kernel. One of them (reported in [0]) is during an attempt
to pin/reuse BPF ringbuf.

Move adjust_ringbuf_sz() helper closer to its first actual use. The
implementation of the helper is unchanged.

Also make detection of whether bpf_object is already loaded more robust
by checking obj->loaded explicitly, given that map->fd can be < 0 even
if bpf_object is already loaded due to ability to disable map creation
with bpf_map__set_autocreate(map, false).

  [0] Closes: https://github.com/libbpf/libbpf/pull/530

Fixes: 0087a681fa ("libbpf: Automatically fix up BPF_MAP_TYPE_RINGBUF size, if necessary")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/r/20220715230952.2219271-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 10:01:20 -07:00
Andrii Nakryiko a1ac9fd6c6 libbpf: fallback to tracefs mount point if debugfs is not mounted
Teach libbpf to fallback to tracefs mount point (/sys/kernel/tracing) if
debugfs (/sys/kernel/debug/tracing) isn't mounted.

Acked-by: Yonghong Song <yhs@fb.com>
Suggested-by: Connor O'Brien <connoro@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220715185736.898848-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:54:28 -07:00
Andrii Nakryiko 708ac5bea0 libbpf: add ksyscall/kretsyscall sections support for syscall kprobes
Add SEC("ksyscall")/SEC("ksyscall/<syscall_name>") and corresponding
kretsyscall variants (for return kprobes) to allow users to kprobe
syscall functions in kernel. These special sections allow to ignore
complexities and differences between kernel versions and host
architectures when it comes to syscall wrapper and corresponding
__<arch>_sys_<syscall> vs __se_sys_<syscall> differences, depending on
whether host kernel has CONFIG_ARCH_HAS_SYSCALL_WRAPPER (though libbpf
itself doesn't rely on /proc/config.gz for detecting this, see
BPF_KSYSCALL patch for how it's done internally).

Combined with the use of BPF_KSYSCALL() macro, this allows to just
specify intended syscall name and expected input arguments and leave
dealing with all the variations to libbpf.

In addition to SEC("ksyscall+") and SEC("kretsyscall+") add
bpf_program__attach_ksyscall() API which allows to specify syscall name
at runtime and provide associated BPF cookie value.

At the moment SEC("ksyscall") and bpf_program__attach_ksyscall() do not
handle all the calling convention quirks for mmap(), clone() and compat
syscalls. It also only attaches to "native" syscall interfaces. If host
system supports compat syscalls or defines 32-bit syscalls in 64-bit
kernel, such syscall interfaces won't be attached to by libbpf.

These limitations may or may not change in the future. Therefore it is
recommended to use SEC("kprobe") for these syscalls or if working with
compat and 32-bit interfaces is required.

Tested-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220714070755.3235561-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:33:18 -07:00
Andrii Nakryiko 6f5d467d55 libbpf: improve BPF_KPROBE_SYSCALL macro and rename it to BPF_KSYSCALL
Improve BPF_KPROBE_SYSCALL (and rename it to shorter BPF_KSYSCALL to
match libbpf's SEC("ksyscall") section name, added in next patch) to use
__kconfig variable to determine how to properly fetch syscall arguments.

Instead of relying on hard-coded knowledge of whether kernel's
architecture uses syscall wrapper or not (which only reflects the latest
kernel versions, but is not necessarily true for older kernels and won't
necessarily hold for later kernel versions on some particular host
architecture), determine this at runtime by attempting to create
perf_event (with fallback to kprobe event creation through tracefs on
legacy kernels, just like kprobe attachment code is doing) for kernel
function that would correspond to bpf() syscall on a system that has
CONFIG_ARCH_HAS_SYSCALL_WRAPPER set (e.g., for x86-64 it would try
'__x64_sys_bpf').

If host kernel uses syscall wrapper, syscall kernel function's first
argument is a pointer to struct pt_regs that then contains syscall
arguments. In such case we need to use bpf_probe_read_kernel() to fetch
actual arguments (which we do through BPF_CORE_READ() macro) from inner
pt_regs.

But if the kernel doesn't use syscall wrapper approach, input
arguments can be read from struct pt_regs directly with no probe reading.

All this feature detection is done without requiring /proc/config.gz
existence and parsing, and BPF-side helper code uses newly added
LINUX_HAS_SYSCALL_WRAPPER virtual __kconfig extern to keep in sync with
user-side feature detection of libbpf.

BPF_KSYSCALL() macro can be used both with SEC("kprobe") programs that
define syscall function explicitly (e.g., SEC("kprobe/__x64_sys_bpf"))
and SEC("ksyscall") program added in the next patch (which are the same
kprobe program with added benefit of libbpf determining correct kernel
function name automatically).

Kretprobe and kretsyscall (added in next patch) programs don't need
BPF_KSYSCALL as they don't provide access to input arguments. Normal
BPF_KRETPROBE is completely sufficient and is recommended.

Tested-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220714070755.3235561-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:33:18 -07:00
Andrii Nakryiko 55d00c37eb libbpf: generalize virtual __kconfig externs and use it for USDT
Libbpf supports single virtual __kconfig extern currently: LINUX_KERNEL_VERSION.
LINUX_KERNEL_VERSION isn't coming from /proc/kconfig.gz and is intead
customly filled out by libbpf.

This patch generalizes this approach to support more such virtual
__kconfig externs. One such extern added in this patch is
LINUX_HAS_BPF_COOKIE which is used for BPF-side USDT supporting code in
usdt.bpf.h instead of using CO-RE-based enum detection approach for
detecting bpf_get_attach_cookie() BPF helper. This allows to remove
otherwise not needed CO-RE dependency and keeps user-space and BPF-side
parts of libbpf's USDT support strictly in sync in terms of their
feature detection.

We'll use similar approach for syscall wrapper detection for
BPF_KSYSCALL() BPF-side macro in follow up patch.

Generally, currently libbpf reserves CONFIG_ prefix for Kconfig values
and LINUX_ for virtual libbpf-backed externs. In the future we might
extend the set of prefixes that are supported. This can be done without
any breaking changes, as currently any __kconfig extern with
unrecognized name is rejected.

For LINUX_xxx externs we support the normal "weak rule": if libbpf
doesn't recognize given LINUX_xxx extern but such extern is marked as
__weak, it is not rejected and defaults to zero.  This follows
CONFIG_xxx handling logic and will allow BPF applications to
opportunistically use newer libbpf virtual externs without breaking on
older libbpf versions unnecessarily.

Tested-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220714070755.3235561-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-07-19 09:33:17 -07:00
Jon Doron 9ff5efdeb0 libbpf: perfbuf: Add API to get the ring buffer
Add support for writing a custom event reader, by exposing the ring
buffer.

With the new API perf_buffer__buffer() you will get access to the
raw mmaped()'ed per-cpu underlying memory of the ring buffer.

This region contains both the perf buffer data and header
(struct perf_event_mmap_page), which manages the ring buffer
state (head/tail positions, when accessing the head/tail position
it's important to take into consideration SMP).
With this type of low level access one can implement different types of
consumers here are few simple examples where this API helps with:

1. perf_event_read_simple is allocating using malloc, perhaps you want
   to handle the wrap-around in some other way.
2. Since perf buf is per-cpu then the order of the events is not
   guarnteed, for example:
   Given 3 events where each event has a timestamp t0 < t1 < t2,
   and the events are spread on more than 1 CPU, then we can end
   up with the following state in the ring buf:
   CPU[0] => [t0, t2]
   CPU[1] => [t1]
   When you consume the events from CPU[0], you could know there is
   a t1 missing, (assuming there are no drops, and your event data
   contains a sequential index).
   So now one can simply do the following, for CPU[0], you can store
   the address of t0 and t2 in an array (without moving the tail, so
   there data is not perished) then move on the CPU[1] and set the
   address of t1 in the same array.
   So you end up with something like:
   void **arr[] = [&t0, &t1, &t2], now you can consume it orderely
   and move the tails as you process in order.
3. Assuming there are multiple CPUs and we want to start draining the
   messages from them, then we can "pick" with which one to start with
   according to the remaining free space in the ring buffer.

Signed-off-by: Jon Doron <jond@wiz.io>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220715181122.149224-1-arilou@gmail.com
2022-07-15 12:53:22 -07:00
Yury Norov 4dea97f863 lib/bitmap: change type of bitmap_weight to unsigned long
bitmap_weight() doesn't return negative values, so change it's type
to unsigned long. It may help compiler to generate better code and
catch bugs.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-07-15 06:35:54 -07:00
Yury Norov e2863a7859 lib/bitmap: change return types to bool where appropriate
Some bitmap functions return boolean results in int variables. Fix it
by changing return types to bool.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
2022-07-14 15:21:43 -07:00
Anquan Wu bf3f003785 libbpf: Fix the name of a reused map
BPF map name is limited to BPF_OBJ_NAME_LEN.
A map name is defined as being longer than BPF_OBJ_NAME_LEN,
it will be truncated to BPF_OBJ_NAME_LEN when a userspace program
calls libbpf to create the map. A pinned map also generates a path
in the /sys. If the previous program wanted to reuse the map,
it can not get bpf_map by name, because the name of the map is only
partially the same as the name which get from pinned path.

The syscall information below show that map name "process_pinned_map"
is truncated to "process_pinned_".

    bpf(BPF_OBJ_GET, {pathname="/sys/fs/bpf/process_pinned_map",
    bpf_fd=0, file_flags=0}, 144) = -1 ENOENT (No such file or directory)

    bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_HASH, key_size=4,
    value_size=4,max_entries=1024, map_flags=0, inner_map_fd=0,
    map_name="process_pinned_",map_ifindex=0, btf_fd=3, btf_key_type_id=6,
    btf_value_type_id=10,btf_vmlinux_value_type_id=0}, 72) = 4

This patch check that if the name of pinned map are the same as the
actual name for the first (BPF_OBJ_NAME_LEN - 1),
bpf map still uses the name which is included in bpf object.

Fixes: 26736eb9a4 ("tools: libbpf: allow map reuse")
Signed-off-by: Anquan Wu <leiqi96@hotmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/OSZP286MB1725CEA1C95C5CB8E7CCC53FB8869@OSZP286MB1725.JPNP286.PROD.OUTLOOK.COM
2022-07-13 22:18:37 -07:00
Hengqi Chen 8ed2f5a6f3 libbpf: Error out when binary_path is NULL for uprobe and USDT
binary_path is a required non-null parameter for bpf_program__attach_usdt
and bpf_program__attach_uprobe_opts. Check it against NULL to prevent
coredump on strchr.

Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220712025745.2703995-1-hengqi.chen@gmail.com
2022-07-13 12:02:59 -07:00
Jakub Kicinski 0076cad301 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-07-09

We've added 94 non-merge commits during the last 19 day(s) which contain
a total of 125 files changed, 5141 insertions(+), 6701 deletions(-).

The main changes are:

1) Add new way for performing BTF type queries to BPF, from Daniel Müller.

2) Add inlining of calls to bpf_loop() helper when its function callback is
   statically known, from Eduard Zingerman.

3) Implement BPF TCP CC framework usability improvements, from Jörn-Thorben Hinz.

4) Add LSM flavor for attaching per-cgroup BPF programs to existing LSM
   hooks, from Stanislav Fomichev.

5) Remove all deprecated libbpf APIs in prep for 1.0 release, from Andrii Nakryiko.

6) Add benchmarks around local_storage to BPF selftests, from Dave Marchevsky.

7) AF_XDP sample removal (given move to libxdp) and various improvements around AF_XDP
   selftests, from Magnus Karlsson & Maciej Fijalkowski.

8) Add bpftool improvements for memcg probing and bash completion, from Quentin Monnet.

9) Add arm64 JIT support for BPF-2-BPF coupled with tail calls, from Jakub Sitnicki.

10) Sockmap optimizations around throughput of UDP transmissions which have been
    improved by 61%, from Cong Wang.

11) Rework perf's BPF prologue code to remove deprecated functions, from Jiri Olsa.

12) Fix sockmap teardown path to avoid sleepable sk_psock_stop, from John Fastabend.

13) Fix libbpf's cleanup around legacy kprobe/uprobe on error case, from Chuang Wang.

14) Fix libbpf's bpf_helpers.h to work with gcc for the case of its sec/pragma
    macro, from James Hilliard.

15) Fix libbpf's pt_regs macros for riscv to use a0 for RC register, from Yixun Lan.

16) Fix bpftool to show the name of type BPF_OBJ_LINK, from Yafang Shao.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (94 commits)
  selftests/bpf: Fix xdp_synproxy build failure if CONFIG_NF_CONNTRACK=m/n
  bpf: Correctly propagate errors up from bpf_core_composites_match
  libbpf: Disable SEC pragma macro on GCC
  bpf: Check attach_func_proto more carefully in check_return_code
  selftests/bpf: Add test involving restrict type qualifier
  bpftool: Add support for KIND_RESTRICT to gen min_core_btf command
  MAINTAINERS: Add entry for AF_XDP selftests files
  selftests, xsk: Rename AF_XDP testing app
  bpf, docs: Remove deprecated xsk libbpf APIs description
  selftests/bpf: Add benchmark for local_storage RCU Tasks Trace usage
  libbpf, riscv: Use a0 for RC register
  libbpf: Remove unnecessary usdt_rel_ip assignments
  selftests/bpf: Fix few more compiler warnings
  selftests/bpf: Fix bogus uninitialized variable warning
  bpftool: Remove zlib feature test from Makefile
  libbpf: Cleanup the legacy uprobe_event on failed add/attach_event()
  libbpf: Fix wrong variable used in perf_event_uprobe_open_legacy()
  libbpf: Cleanup the legacy kprobe_event on failed add/attach_event()
  selftests/bpf: Add type match test against kernel's task_struct
  selftests/bpf: Add nested type to type based tests
  ...
====================

Link: https://lore.kernel.org/r/20220708233145.32365-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-09 12:24:16 -07:00
Daniel Müller 06cd4e9d5d bpf: Correctly propagate errors up from bpf_core_composites_match
This change addresses a comment made earlier [0] about a missing return
of an error when __bpf_core_types_match is invoked from
bpf_core_composites_match, which could have let to us erroneously
ignoring errors.

Regarding the typedef name check pointed out in the same context, it is
not actually an issue, because callers of the function perform a name
check for the root type anyway. To make that more obvious, let's add
comments to the function (similar to what we have for
bpf_core_types_are_compat, which is called in pretty much the same
context).

[0]: https://lore.kernel.org/bpf/165708121449.4919.13204634393477172905.git-patchwork-notify@kernel.org/T/#m55141e8f8cfd2e8d97e65328fa04852870d01af6

Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220707211931.3415440-1-deso@posteo.net
2022-07-08 15:31:43 -07:00
James Hilliard 18410251f6 libbpf: Disable SEC pragma macro on GCC
It seems the gcc preprocessor breaks with pragmas when surrounding
__attribute__.

Disable these pragmas on GCC due to upstream bugs see:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55578
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90400

Fixes errors like:
error: expected identifier or '(' before '#pragma'
  106 | SEC("cgroup/bind6")
      | ^~~

error: expected '=', ',', ';', 'asm' or '__attribute__' before '#pragma'
  114 | char _license[] SEC("license") = "GPL";
      | ^~~

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220706111839.1247911-1-james.hilliard1@gmail.com
2022-07-08 15:11:34 -07:00
Yixun Lan 935dc35c75 libbpf, riscv: Use a0 for RC register
According to the RISC-V calling convention register usage here [0], a0
is used as return value register, so rename it to make it consistent
with the spec.

  [0] section 18.2, table 18.2
      https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf

Fixes: 589fed479b ("riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h")
Signed-off-by: Yixun Lan <dlan@gentoo.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn@kernel.org>
Acked-by: Amjad OULED-AMEUR <ouledameur.amjad@gmail.com>
Link: https://lore.kernel.org/bpf/20220706140204.47926-1-dlan@gentoo.org
2022-07-07 16:30:04 +02:00
Andrii Nakryiko 7c8121af1b libbpf: Remove unnecessary usdt_rel_ip assignments
Coverity detected that usdt_rel_ip is unconditionally overwritten
anyways, so there is no need to unnecessarily initialize it with unused
value. Clean this up.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20220705224818.4026623-4-andrii@kernel.org
2022-07-06 16:46:19 +02:00
Chuang Wang 2655144fb4 libbpf: Cleanup the legacy uprobe_event on failed add/attach_event()
A potential scenario, when an error is returned after
add_uprobe_event_legacy() in perf_event_uprobe_open_legacy(), or
bpf_program__attach_perf_event_opts() in
bpf_program__attach_uprobe_opts() returns an error, the uprobe_event
that was previously created is not cleaned.

So, with this patch, when an error is returned, fix this by adding
remove_uprobe_event_legacy()

Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220629151848.65587-4-nashuiliang@gmail.com
2022-07-05 21:23:03 -07:00
Chuang Wang 5666fc997c libbpf: Fix wrong variable used in perf_event_uprobe_open_legacy()
Use "type" as opposed to "err" in pr_warn() after
determine_uprobe_perf_type_legacy() returns an error.

Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220629151848.65587-3-nashuiliang@gmail.com
2022-07-05 21:21:44 -07:00
Chuang Wang 8094029330 libbpf: Cleanup the legacy kprobe_event on failed add/attach_event()
Before the 0bc11ed5ab commit ("kprobes: Allow kprobes coexist with
livepatch"), in a scenario where livepatch and kprobe coexist on the
same function entry, the creation of kprobe_event using
add_kprobe_event_legacy() will be successful, at the same time as a
trace event (e.g. /debugfs/tracing/events/kprobe/XXX) will exist, but
perf_event_open() will return an error because both livepatch and kprobe
use FTRACE_OPS_FL_IPMODIFY. As follows:

1) add a livepatch

$ insmod livepatch-XXX.ko

2) add a kprobe using tracefs API (i.e. add_kprobe_event_legacy)

$ echo 'p:mykprobe XXX' > /sys/kernel/debug/tracing/kprobe_events

3) enable this kprobe (i.e. sys_perf_event_open)

This will return an error, -EBUSY.

On Andrii Nakryiko's comment, few error paths in
bpf_program__attach_kprobe_opts() that should need to call
remove_kprobe_event_legacy().

With this patch, whenever an error is returned after
add_kprobe_event_legacy() or bpf_program__attach_perf_event_opts(), this
ensures that the created kprobe_event is cleaned.

Signed-off-by: Chuang Wang <nashuiliang@gmail.com>
Signed-off-by: Jingren Zhou <zhoujingren@didiglobal.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220629151848.65587-2-nashuiliang@gmail.com
2022-07-05 21:21:41 -07:00
Andrii Nakryiko b8a195dc29 libbpf: add bpf_core_type_matches() helper macro
This patch finalizes support for the proposed type match relation in libbpf by
adding bpf_core_type_matches() macro which emits TYPE_MATCH relocation.

Clang support for this relocation was added in [0].

  [0] https://reviews.llvm.org/D126838

Signed-off-by: Daniel Müller <deso@posteo.net>¬
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>¬
Link: https://lore.kernel.org/bpf/20220628160127.607834-7-deso@posteo.net¬
2022-07-05 21:15:19 -07:00
Daniel Müller ec6209c8d4 bpf, libbpf: Add type match support
This patch adds support for the proposed type match relation to
relo_core where it is shared between userspace and kernel. It plumbs
through both kernel-side and libbpf-side support.

The matching relation is defined as follows (copy from source):
- modifiers and typedefs are stripped (and, hence, effectively ignored)
- generally speaking types need to be of same kind (struct vs. struct, union
  vs. union, etc.)
  - exceptions are struct/union behind a pointer which could also match a
    forward declaration of a struct or union, respectively, and enum vs.
    enum64 (see below)
Then, depending on type:
- integers:
  - match if size and signedness match
- arrays & pointers:
  - target types are recursively matched
- structs & unions:
  - local members need to exist in target with the same name
  - for each member we recursively check match unless it is already behind a
    pointer, in which case we only check matching names and compatible kind
- enums:
  - local variants have to have a match in target by symbolic name (but not
    numeric value)
  - size has to match (but enum may match enum64 and vice versa)
- function pointers:
  - number and position of arguments in local type has to match target
  - for each argument and the return value we recursively check match

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220628160127.607834-5-deso@posteo.net
2022-07-05 21:14:25 -07:00
Daniel Müller 3c660a5d86 bpf: Introduce TYPE_MATCH related constants/macros
In order to provide type match support we require a new type of
relocation which, in turn, requires toolchain support. Recent LLVM/Clang
versions support a new value for the last argument to the
__builtin_preserve_type_info builtin, for example.
With this change we introduce the necessary constants into relevant
header files, mirroring what the compiler may support.

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220628160127.607834-2-deso@posteo.net
2022-07-05 20:24:12 -07:00
Stanislav Fomichev a4b2f3cf69 libbpf: implement bpf_prog_query_opts
Implement bpf_prog_query_opts as a more expendable version of
bpf_prog_query. Expose new prog_attach_flags and attach_btf_func_id as
well:

* prog_attach_flags is a per-program attach_type; relevant only for
  lsm cgroup program which might have different attach_flags
  per attach_btf_id
* attach_btf_func_id is a new field expose for prog_query which
  specifies real btf function id for lsm cgroup attachments

Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-10-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:52 -07:00
Stanislav Fomichev bffcf34878 libbpf: add lsm_cgoup_sock type
lsm_cgroup/ is the prefix for BPF_LSM_CGROUP.

Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-9-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-29 13:21:52 -07:00
Andrii Nakryiko ab9a5a05dc libbpf: fix up few libbpf.map problems
Seems like we missed to add 2 APIs to libbpf.map and another API was
misspelled. Fix it in libbpf.map.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-16-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:33 -07:00
Andrii Nakryiko bd054102a8 libbpf: enforce strict libbpf 1.0 behaviors
Remove support for legacy features and behaviors that previously had to
be disabled by calling libbpf_set_strict_mode():
  - legacy BPF map definitions are not supported now;
  - RLIMIT_MEMLOCK auto-setting, if necessary, is always on (but see
    libbpf_set_memlock_rlim());
  - program name is used for program pinning (instead of section name);
  - cleaned up error returning logic;
  - entry BPF programs should have SEC() always.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-15-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:33 -07:00
Andrii Nakryiko 450b167fb9 libbpf: clean up SEC() handling
Get rid of sloppy prefix logic and remove deprecated xdp_{devmap,cpumap}
sections.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-13-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:33 -07:00
Andrii Nakryiko cf90a20db8 libbpf: remove internal multi-instance prog support
Clean up internals that had to deal with the possibility of
multi-instance bpf_programs. Libbpf 1.0 doesn't support this, so all
this is not necessary now and can be simplified.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-12-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:33 -07:00
Andrii Nakryiko a11113a2dc libbpf: cleanup LIBBPF_DEPRECATED_SINCE supporting macros for v0.x
Keep the LIBBPF_DEPRECATED_SINCE macro "framework" for future
deprecations, but clean up 0.x related helper macros.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-11-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:33 -07:00
Andrii Nakryiko b4bda502df libbpf: remove multi-instance and custom private data APIs
Remove all the public APIs that are related to creating multi-instance
bpf_programs through custom preprocessing callback and generally working
with them.

Also remove all the bpf_{object,map,program}__[set_]priv() APIs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-10-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko 146bf811f5 libbpf: remove most other deprecated high-level APIs
Remove a bunch of high-level bpf_object/bpf_map/bpf_program related
APIs. All the APIs related to private per-object/map/prog state,
program preprocessing callback, and generally everything multi-instance
related is removed in a separate patch.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-9-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko 9a590538ba libbpf: remove prog_info_linear APIs
Remove prog_info_linear-related APIs previously used by perf.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko 22dd7a58b2 libbpf: clean up perfbuf APIs
Remove deprecated perfbuf APIs and clean up opts structs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko aaf6886d9b libbpf: remove deprecated BTF APIs
Get rid of deprecated BTF-related APIs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko d320fad217 libbpf: remove deprecated probing APIs
Get rid of deprecated feature-probing APIs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko 53e6af3a76 libbpf: remove deprecated XDP APIs
Get rid of deprecated bpf_set_link*() and bpf_get_link*() APIs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko 765a34130e libbpf: remove deprecated low-level APIs
Drop low-level APIs as well as high-level (and very confusingly named)
BPF object loading bpf_prog_load_xattr() and bpf_prog_load_deprecated()
APIs.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Andrii Nakryiko f366006342 libbpf: move xsk.{c,h} into selftests/bpf
Remove deprecated xsk APIs from libbpf. But given we have selftests
relying on this, move those files (with minimal adjustments to make them
compilable) under selftests/bpf.

We also remove all the removed APIs from libbpf.map, while overall
keeping version inheritance chain, as most APIs are backwards
compatible so there is no need to reassign them as LIBBPF_1.0.0 versions.

Cc: Magnus Karlsson <magnus.karlsson@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20220627211527.2245459-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-06-28 13:13:32 -07:00
Daniel Müller fd75733da2 bpf: Merge "types_are_compat" logic into relo_core.c
BPF type compatibility checks (bpf_core_types_are_compat()) are
currently duplicated between kernel and user space. That's a historical
artifact more than intentional doing and can lead to subtle bugs where
one implementation is adjusted but another is forgotten.

That happened with the enum64 work, for example, where the libbpf side
was changed (commit 23b2a3a8f6 ("libbpf: Add enum64 relocation
support")) to use the btf_kind_core_compat() helper function but the
kernel side was not (commit 6089fb325c ("bpf: Add btf enum64
support")).

This patch addresses both the duplication issue, by merging both
implementations and moving them into relo_core.c, and fixes the alluded
to kind check (by giving preference to libbpf's already adjusted logic).

For discussion of the topic, please refer to:
https://lore.kernel.org/bpf/CAADnVQKbWR7oarBdewgOBZUPzryhRYvEbkhyPJQHHuxq=0K1gw@mail.gmail.com/T/#mcc99f4a33ad9a322afaf1b9276fb1f0b7add9665

Changelog:
v1 -> v2:
- limited libbpf recursion limit to 32
- changed name to __bpf_core_types_are_compat
- included warning previously present in libbpf version
- merged kernel and user space changes into a single patch

Signed-off-by: Daniel Müller <deso@posteo.net>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220623182934.2582827-1-deso@posteo.net
2022-06-24 14:15:37 -07:00