1. 23 Jul, 2021 6 commits
    • Steven Rostedt (VMware)'s avatar
      tracepoints: Update static_call before tp_funcs when adding a tracepoint · 352384d5
      Steven Rostedt (VMware) authored
      Because of the significant overhead that retpolines pose on indirect
      calls, the tracepoint code was updated to use the new "static_calls" that
      can modify the running code to directly call a function instead of using
      an indirect caller, and this function can be changed at runtime.
      
      In the tracepoint code that calls all the registered callbacks that are
      attached to a tracepoint, the following is done:
      
      	it_func_ptr = rcu_dereference_raw((&__tracepoint_##name)->funcs);
      	if (it_func_ptr) {
      		__data = (it_func_ptr)->data;
      		static_call(tp_func_##name)(__data, args);
      	}
      
      If there's just a single callback, the static_call is updated to just call
      that callback directly. Once another handler is added, then the static
      caller is updated to call the iterator, that simply loops over all the
      funcs in the array and calls each of the callbacks like the old method
      using indirect calling.
      
      The issue was discovered with a race between updating the funcs array and
      updating the static_call. The funcs array was updated first and then the
      static_call was updated. This is not an issue as long as the first element
      in the old array is the same as the first element in the new array. But
      that assumption is incorrect, because callbacks also have a priority
      field, and if there's a callback added that has a higher priority than the
      callback on the old array, then it will become the first callback in the
      new array. This means that it is possible to call the old callback with
      the new callback data element, which can cause a kernel panic.
      
      	static_call = callback1()
      	funcs[] = {callback1,data1};
      	callback2 has higher priority than callback1
      
      	CPU 1				CPU 2
      	-----				-----
      
         new_funcs = {callback2,data2},
                     {callback1,data1}
      
         rcu_assign_pointer(tp->funcs, new_funcs);
      
        /*
         * Now tp->funcs has the new array
         * but the static_call still calls callback1
         */
      
      				it_func_ptr = tp->funcs [ new_funcs ]
      				data = it_func_ptr->data [ data2 ]
      				static_call(callback1, data);
      
      				/* Now callback1 is called with
      				 * callback2's data */
      
      				[ KERNEL PANIC ]
      
         update_static_call(iterator);
      
      To prevent this from happening, always switch the static_call to the
      iterator before assigning the tp->funcs to the new array. The iterator will
      always properly match the callback with its data.
      
      To trigger this bug:
      
        In one terminal:
      
          while :; do hackbench 50; done
      
        In another terminal
      
          echo 1 > /sys/kernel/tracing/events/sched/sched_waking/enable
          while :; do
              echo 1 > /sys/kernel/tracing/set_event_pid;
              sleep 0.5
              echo 0 > /sys/kernel/tracing/set_event_pid;
              sleep 0.5
         done
      
      And it doesn't take long to crash. This is because the set_event_pid adds
      a callback to the sched_waking tracepoint with a high priority, which will
      be called before the sched_waking trace event callback is called.
      
      Note, the removal to a single callback updates the array first, before
      changing the static_call to single callback, which is the proper order as
      the first element in the array is the same as what the static_call is
      being changed to.
      
      Link: https://lore.kernel.org/io-uring/4ebea8f0-58c9-e571-fd30-0ce4f6f09c70@samba.org/
      
      Cc: stable@vger.kernel.org
      Fixes: d25e37d8 ("tracepoint: Optimize using static_call()")
      Reported-by: default avatarStefan Metzmacher <metze@samba.org>
      tested-by: default avatarStefan Metzmacher <metze@samba.org>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      352384d5
    • Colin Ian King's avatar
      ftrace: Remove redundant initialization of variable ret · 3b1a8f45
      Colin Ian King authored
      The variable ret is being initialized with a value that is never
      read, it is being updated later on. The assignment is redundant and
      can be removed.
      
      Link: https://lkml.kernel.org/r/20210721120915.122278-1-colin.king@canonical.com
      
      Addresses-Coverity: ("Unused value")
      Signed-off-by: default avatarColin Ian King <colin.king@canonical.com>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      3b1a8f45
    • Nicolas Saenz Julienne's avatar
      ftrace: Avoid synchronize_rcu_tasks_rude() call when not necessary · 68e83498
      Nicolas Saenz Julienne authored
      synchronize_rcu_tasks_rude() triggers IPIs and forces rescheduling on
      all CPUs. It is a costly operation and, when targeting nohz_full CPUs,
      very disrupting (hence the name). So avoid calling it when 'old_hash'
      doesn't need to be freed.
      
      Link: https://lkml.kernel.org/r/20210721114726.1545103-1-nsaenzju@redhat.comSigned-off-by: default avatarNicolas Saenz Julienne <nsaenzju@redhat.com>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      68e83498
    • Steven Rostedt (VMware)'s avatar
      tracing: Clean up alloc_synth_event() · 9528c195
      Steven Rostedt (VMware) authored
      alloc_synth_event() currently has the following code to initialize the
      event fields and dynamic_fields:
      
      	for (i = 0, j = 0; i < n_fields; i++) {
      		event->fields[i] = fields[i];
      
      		if (fields[i]->is_dynamic) {
      			event->dynamic_fields[j] = fields[i];
      			event->dynamic_fields[j]->field_pos = i;
      			event->dynamic_fields[j++] = fields[i];
      			event->n_dynamic_fields++;
      		}
      	}
      
      1) It would make more sense to have all fields keep track of their
         field_pos.
      
      2) event->dynmaic_fields[j] is assigned twice for no reason.
      
      3) We can move updating event->n_dynamic_fields outside the loop, and just
         assign it to j.
      
      This combination makes the code much cleaner.
      
      Link: https://lkml.kernel.org/r/20210721195341.29bb0f77@oasis.local.homeSigned-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      9528c195
    • Steven Rostedt (VMware)'s avatar
      tracing/histogram: Rename "cpu" to "common_cpu" · 1e3bac71
      Steven Rostedt (VMware) authored
      Currently the histogram logic allows the user to write "cpu" in as an
      event field, and it will record the CPU that the event happened on.
      
      The problem with this is that there's a lot of events that have "cpu"
      as a real field, and using "cpu" as the CPU it ran on, makes it
      impossible to run histograms on the "cpu" field of events.
      
      For example, if I want to have a histogram on the count of the
      workqueue_queue_work event on its cpu field, running:
      
       ># echo 'hist:keys=cpu' > events/workqueue/workqueue_queue_work/trigger
      
      Gives a misleading and wrong result.
      
      Change the command to "common_cpu" as no event should have "common_*"
      fields as that's a reserved name for fields used by all events. And
      this makes sense here as common_cpu would be a field used by all events.
      
      Now we can even do:
      
       ># echo 'hist:keys=common_cpu,cpu if cpu < 100' > events/workqueue/workqueue_queue_work/trigger
       ># cat events/workqueue/workqueue_queue_work/hist
       # event histogram
       #
       # trigger info: hist:keys=common_cpu,cpu:vals=hitcount:sort=hitcount:size=2048 if cpu < 100 [active]
       #
      
       { common_cpu:          0, cpu:          2 } hitcount:          1
       { common_cpu:          0, cpu:          4 } hitcount:          1
       { common_cpu:          7, cpu:          7 } hitcount:          1
       { common_cpu:          0, cpu:          7 } hitcount:          1
       { common_cpu:          0, cpu:          1 } hitcount:          1
       { common_cpu:          0, cpu:          6 } hitcount:          2
       { common_cpu:          0, cpu:          5 } hitcount:          2
       { common_cpu:          1, cpu:          1 } hitcount:          4
       { common_cpu:          6, cpu:          6 } hitcount:          4
       { common_cpu:          5, cpu:          5 } hitcount:         14
       { common_cpu:          4, cpu:          4 } hitcount:         26
       { common_cpu:          0, cpu:          0 } hitcount:         39
       { common_cpu:          2, cpu:          2 } hitcount:        184
      
      Now for backward compatibility, I added a trick. If "cpu" is used, and
      the field is not found, it will fall back to "common_cpu" and work as
      it did before. This way, it will still work for old programs that use
      "cpu" to get the actual CPU, but if the event has a "cpu" as a field, it
      will get that event's "cpu" field, which is probably what it wants
      anyway.
      
      I updated the tracefs/README to include documentation about both the
      common_timestamp and the common_cpu. This way, if that text is present in
      the README, then an application can know that common_cpu is supported over
      just plain "cpu".
      
      Link: https://lkml.kernel.org/r/20210721110053.26b4f641@oasis.local.home
      
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: stable@vger.kernel.org
      Fixes: 8b7622bf ("tracing: Add cpu field for hist triggers")
      Reviewed-by: default avatarTom Zanussi <zanussi@kernel.org>
      Reviewed-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      1e3bac71
    • Steven Rostedt (VMware)'s avatar
      tracing: Synthetic event field_pos is an index not a boolean · 3b13911a
      Steven Rostedt (VMware) authored
      Performing the following:
      
       ># echo 'wakeup_lat s32 pid; u64 delta; char wake_comm[]' > synthetic_events
       ># echo 'hist:keys=pid:__arg__1=common_timestamp.usecs' > events/sched/sched_waking/trigger
       ># echo 'hist:keys=next_pid:pid=next_pid,delta=common_timestamp.usecs-$__arg__1:onmatch(sched.sched_waking).trace(wakeup_lat,$pid,$delta,prev_comm)'\
            > events/sched/sched_switch/trigger
       ># echo 1 > events/synthetic/enable
      
      Crashed the kernel:
      
       BUG: kernel NULL pointer dereference, address: 000000000000001b
       #PF: supervisor read access in kernel mode
       #PF: error_code(0x0000) - not-present page
       PGD 0 P4D 0
       Oops: 0000 [#1] PREEMPT SMP
       CPU: 7 PID: 0 Comm: swapper/7 Not tainted 5.13.0-rc5-test+ #104
       Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
       RIP: 0010:strlen+0x0/0x20
       Code: f6 82 80 2b 0b bc 20 74 11 0f b6 50 01 48 83 c0 01 f6 82 80 2b 0b bc
        20 75 ef c3 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <80> 3f 00 74 10
        48 89 f8 48 83 c0 01 80 38 9 f8 c3 31
       RSP: 0018:ffffaa75000d79d0 EFLAGS: 00010046
       RAX: 0000000000000002 RBX: ffff9cdb55575270 RCX: 0000000000000000
       RDX: ffff9cdb58c7a320 RSI: ffffaa75000d7b40 RDI: 000000000000001b
       RBP: ffffaa75000d7b40 R08: ffff9cdb40a4f010 R09: ffffaa75000d7ab8
       R10: ffff9cdb4398c700 R11: 0000000000000008 R12: ffff9cdb58c7a320
       R13: ffff9cdb55575270 R14: ffff9cdb58c7a000 R15: 0000000000000018
       FS:  0000000000000000(0000) GS:ffff9cdb5aa00000(0000) knlGS:0000000000000000
       CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
       CR2: 000000000000001b CR3: 00000000c0612006 CR4: 00000000001706e0
       Call Trace:
        trace_event_raw_event_synth+0x90/0x1d0
        action_trace+0x5b/0x70
        event_hist_trigger+0x4bd/0x4e0
        ? cpumask_next_and+0x20/0x30
        ? update_sd_lb_stats.constprop.0+0xf6/0x840
        ? __lock_acquire.constprop.0+0x125/0x550
        ? find_held_lock+0x32/0x90
        ? sched_clock_cpu+0xe/0xd0
        ? lock_release+0x155/0x440
        ? update_load_avg+0x8c/0x6f0
        ? enqueue_entity+0x18a/0x920
        ? __rb_reserve_next+0xe5/0x460
        ? ring_buffer_lock_reserve+0x12a/0x3f0
        event_triggers_call+0x52/0xe0
        trace_event_buffer_commit+0x1ae/0x240
        trace_event_raw_event_sched_switch+0x114/0x170
        __traceiter_sched_switch+0x39/0x50
        __schedule+0x431/0xb00
        schedule_idle+0x28/0x40
        do_idle+0x198/0x2e0
        cpu_startup_entry+0x19/0x20
        secondary_startup_64_no_verify+0xc2/0xcb
      
      The reason is that the dynamic events array keeps track of the field
      position of the fields array, via the field_pos variable in the
      synth_field structure. Unfortunately, that field is a boolean for some
      reason, which means any field_pos greater than 1 will be a bug (in this
      case it was 2).
      
      Link: https://lkml.kernel.org/r/20210721191008.638bce34@oasis.local.home
      
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: stable@vger.kernel.org
      Fixes: bd82631d ("tracing: Add support for dynamic strings to synthetic events")
      Reviewed-by: default avatarTom Zanussi <zanussi@kernel.org>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      3b13911a
  2. 22 Jul, 2021 1 commit
    • Haoran Luo's avatar
      tracing: Fix bug in rb_per_cpu_empty() that might cause deadloop. · 67f0d6d9
      Haoran Luo authored
      The "rb_per_cpu_empty()" misinterpret the condition (as not-empty) when
      "head_page" and "commit_page" of "struct ring_buffer_per_cpu" points to
      the same buffer page, whose "buffer_data_page" is empty and "read" field
      is non-zero.
      
      An error scenario could be constructed as followed (kernel perspective):
      
      1. All pages in the buffer has been accessed by reader(s) so that all of
      them will have non-zero "read" field.
      
      2. Read and clear all buffer pages so that "rb_num_of_entries()" will
      return 0 rendering there's no more data to read. It is also required
      that the "read_page", "commit_page" and "tail_page" points to the same
      page, while "head_page" is the next page of them.
      
      3. Invoke "ring_buffer_lock_reserve()" with large enough "length"
      so that it shot pass the end of current tail buffer page. Now the
      "head_page", "commit_page" and "tail_page" points to the same page.
      
      4. Discard current event with "ring_buffer_discard_commit()", so that
      "head_page", "commit_page" and "tail_page" points to a page whose buffer
      data page is now empty.
      
      When the error scenario has been constructed, "tracing_read_pipe" will
      be trapped inside a deadloop: "trace_empty()" returns 0 since
      "rb_per_cpu_empty()" returns 0 when it hits the CPU containing such
      constructed ring buffer. Then "trace_find_next_entry_inc()" always
      return NULL since "rb_num_of_entries()" reports there's no more entry
      to read. Finally "trace_seq_to_user()" returns "-EBUSY" spanking
      "tracing_read_pipe" back to the start of the "waitagain" loop.
      
      I've also written a proof-of-concept script to construct the scenario
      and trigger the bug automatically, you can use it to trace and validate
      my reasoning above:
      
        https://github.com/aegistudio/RingBufferDetonator.git
      
      Tests has been carried out on linux kernel 5.14-rc2
      (2734d6c1), my fixed version
      of kernel (for testing whether my update fixes the bug) and
      some older kernels (for range of affected kernels). Test result is
      also attached to the proof-of-concept repository.
      
      Link: https://lore.kernel.org/linux-trace-devel/YPaNxsIlb2yjSi5Y@aegistudio/
      Link: https://lore.kernel.org/linux-trace-devel/YPgrN85WL9VyrZ55@aegistudio
      
      Cc: stable@vger.kernel.org
      Fixes: bf41a158 ("ring-buffer: make reentrant")
      Suggested-by: default avatarLinus Torvalds <torvalds@linuxfoundation.org>
      Signed-off-by: default avatarHaoran Luo <www@aegistudio.net>
      Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
      67f0d6d9
  3. 18 Jul, 2021 13 commits
    • Linus Torvalds's avatar
      Linux 5.14-rc2 · 2734d6c1
      Linus Torvalds authored
      2734d6c1
    • Linus Torvalds's avatar
      Merge tag 'perf-tools-fixes-for-v5.14-2021-07-18' of... · 8c25c447
      Linus Torvalds authored
      Merge tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
      
      Pull perf tools fixes from Arnaldo Carvalho de Melo:
      
       - Skip invalid hybrid PMU on hybrid systems when the atom (little) CPUs
         are offlined.
      
       - Fix 'perf test' problems related to the recently added hybrid
         (BIG/little) code.
      
       - Split ARM's coresight (hw tracing) decode by aux records to avoid
         fatal decoding errors.
      
       - Fix add event failure in 'perf probe' when running 32-bit perf in a
         64-bit kernel.
      
       - Fix 'perf sched record' failure when CONFIG_SCHEDSTATS is not set.
      
       - Fix memory and refcount leaks detected by ASAn when running 'perf
         test', should be clean of warnings now.
      
       - Remove broken definition of __LITTLE_ENDIAN from tools'
         linux/kconfig.h, which was breaking the build in some systems.
      
       - Cast PTHREAD_STACK_MIN to int as it may turn into 'long
         sysconf(__SC_THREAD_STACK_MIN_VALUE), breaking the build in some
         systems.
      
       - Fix libperf build error with LIBPFM4=1.
      
       - Sync UAPI files changed by the memfd_secret new syscall.
      
      * tag 'perf-tools-fixes-for-v5.14-2021-07-18' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (35 commits)
        perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set
        perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel
        perf data: Close all files in close_dir()
        perf probe-file: Delete namelist in del_events() on the error path
        perf test bpf: Free obj_buf
        perf trace: Free strings in trace__parse_events_option()
        perf trace: Free syscall tp fields in evsel->priv
        perf trace: Free syscall->arg_fmt
        perf trace: Free malloc'd trace fields on exit
        perf lzma: Close lzma stream on exit
        perf script: Fix memory 'threads' and 'cpus' leaks on exit
        perf script: Release zstd data
        perf session: Cleanup trace_event
        perf inject: Close inject.output on exit
        perf report: Free generated help strings for sort option
        perf env: Fix memory leak of cpu_pmu_caps
        perf test maps__merge_in: Fix memory leak of maps
        perf dso: Fix memory leak in dso__new_map()
        perf test event_update: Fix memory leak of unit
        perf test event_update: Fix memory leak of evlist
        ...
      8c25c447
    • Linus Torvalds's avatar
      Merge tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux · f0eb870a
      Linus Torvalds authored
      Pull xfs fixes from Darrick Wong:
       "A few fixes for issues in the new online shrink code, additional
        corrections for my recent bug-hunt w.r.t. extent size hints on
        realtime, and improved input checking of the GROWFSRT ioctl.
      
        IOW, the usual 'I somehow got bored during the merge window and
        resumed auditing the farther reaches of xfs':
      
         - Fix shrink eligibility checking when sparse inode clusters enabled
      
         - Reset '..' directory entries when unlinking directories to prevent
           verifier errors if fs is shrinked later
      
         - Don't report unusable extent size hints to FSGETXATTR
      
         - Don't warn when extent size hints are unusable because the sysadmin
           configured them that way
      
         - Fix insufficient parameter validation in GROWFSRT ioctl
      
         - Fix integer overflow when adding rt volumes to filesystem"
      
      * tag 'xfs-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
        xfs: detect misaligned rtinherit directory extent size hints
        xfs: fix an integer overflow error in xfs_growfs_rt
        xfs: improve FSGROWFSRT precondition checking
        xfs: don't expose misaligned extszinherit hints to userspace
        xfs: correct the narrative around misaligned rtinherit/extszinherit dirs
        xfs: reset child dir '..' entry when unlinking child
        xfs: check for sparse inode clusters that cross new EOAG when shrinking
      f0eb870a
    • Linus Torvalds's avatar
      Merge tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux · fbf1bddc
      Linus Torvalds authored
      Pull iomap fixes from Darrick Wong:
       "A handful of bugfixes for the iomap code.
      
        There's nothing especially exciting here, just fixes for UBSAN (not
        KASAN as I erroneously wrote in the tag message) warnings about
        undefined behavior in the SEEK_DATA/SEEK_HOLE code, and some
        reshuffling of per-page block state info to fix some problems with
        gfs2.
      
         - Fix KASAN warnings due to integer overflow in SEEK_DATA/SEEK_HOLE
      
         - Fix assertion errors when using inlinedata files on gfs2"
      
      * tag 'iomap-5.14-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
        iomap: Don't create iomap_page objects in iomap_page_mkwrite_actor
        iomap: Don't create iomap_page objects for inline files
        iomap: Permit pages without an iop to enter writeback
        iomap: remove the length variable in iomap_seek_hole
        iomap: remove the length variable in iomap_seek_data
      fbf1bddc
    • Linus Torvalds's avatar
      Merge tag 'kbuild-fixes-v5.14' of... · 6750691a
      Linus Torvalds authored
      Merge tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
      
      Pull Kbuild fixes from Masahiro Yamada:
      
       - Restore the original behavior of scripts/setlocalversion when
         LOCALVERSION is set to empty.
      
       - Show Kconfig prompts even for 'make -s'
      
       - Fix the combination of COFNIG_LTO_CLANG=y and CONFIG_MODVERSIONS=y
         for older GNU Make versions
      
      * tag 'kbuild-fixes-v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
        Documentation: Fix intiramfs script name
        Kbuild: lto: fix module versionings mismatch in GNU make 3.X
        kbuild: do not suppress Kconfig prompts for silent build
        scripts/setlocalversion: fix a bug when LOCALVERSION is empty
      6750691a
    • Robert Richter's avatar
      Documentation: Fix intiramfs script name · 5e60f363
      Robert Richter authored
      Documentation was not changed when renaming the script in commit
      80e715a0 ("initramfs: rename gen_initramfs_list.sh to
      gen_initramfs.sh"). Fixing this.
      
      Basically does:
      
       $ sed -i -e s/gen_initramfs_list.sh/gen_initramfs.sh/g $(git grep -l gen_initramfs_list.sh)
      
      Fixes: 80e715a0 ("initramfs: rename gen_initramfs_list.sh to gen_initramfs.sh")
      Signed-off-by: default avatarRobert Richter <rrichter@amd.com>
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      5e60f363
    • Lecopzer Chen's avatar
      Kbuild: lto: fix module versionings mismatch in GNU make 3.X · 1d11053d
      Lecopzer Chen authored
      When building modules(CONFIG_...=m), I found some of module versions
      are incorrect and set to 0.
      This can be found in build log for first clean build which shows
      
      WARNING: EXPORT symbol "XXXX" [drivers/XXX/XXX.ko] version generation failed,
      symbol will not be versioned.
      
      But in second build(incremental build), the WARNING disappeared and the
      module version becomes valid CRC and make someone who want to change
      modules without updating kernel image can't insert their modules.
      
      The problematic code is
      +	$(foreach n, $(filter-out FORCE,$^),				\
      +		$(if $(wildcard $(n).symversions),			\
      +			; cat $(n).symversions >> $@.symversions))
      
      For example:
        rm -f fs/notify/built-in.a.symversions    ; rm -f fs/notify/built-in.a; \
      llvm-ar cDPrST fs/notify/built-in.a fs/notify/fsnotify.o \
      fs/notify/notification.o fs/notify/group.o ...
      
      `foreach n` shows nothing to `cat` into $(n).symversions because
      `if $(wildcard $(n).symversions)` return nothing, but actually
      they do exist during this line was executed.
      
      -rw-r--r-- 1 root root 168580 Jun 13 19:10 fs/notify/fsnotify.o
      -rw-r--r-- 1 root root    111 Jun 13 19:10 fs/notify/fsnotify.o.symversions
      
      The reason is the $(n).symversions are generated at runtime, but
      Makefile wildcard function expends and checks the file exist or not
      during parsing the Makefile.
      
      Thus fix this by use `test` shell command to check the file
      existence in runtime.
      
      Rebase from both:
      1. [https://lore.kernel.org/lkml/20210616080252.32046-1-lecopzer.chen@mediatek.com/]
      2. [https://lore.kernel.org/lkml/20210702032943.7865-1-lecopzer.chen@mediatek.com/]
      
      Fixes: 38e89184 ("kbuild: lto: fix module versioning")
      Co-developed-by: default avatarSami Tolvanen <samitolvanen@google.com>
      Signed-off-by: default avatarLecopzer Chen <lecopzer.chen@mediatek.com>
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      1d11053d
    • Masahiro Yamada's avatar
      kbuild: do not suppress Kconfig prompts for silent build · d952cfaf
      Masahiro Yamada authored
      When a new CONFIG option is available, Kbuild shows a prompt to get
      the user input.
      
        $ make
        [ snip ]
        Core Scheduling for SMT (SCHED_CORE) [N/y/?] (NEW)
      
      This is the only interactive place in the build process.
      
      Commit 174a1dcc ("kbuild: sink stdout from cmd for silent build")
      suppressed Kconfig prompts as well because syncconfig is invoked by
      the 'cmd' macro. You cannot notice the fact that Kconfig is waiting
      for the user input.
      
      Use 'kecho' to show the equivalent short log without suppressing stdout
      from sub-make.
      
      Fixes: 174a1dcc ("kbuild: sink stdout from cmd for silent build")
      Reported-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      Tested-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      d952cfaf
    • Mikulas Patocka's avatar
      scripts/setlocalversion: fix a bug when LOCALVERSION is empty · 5df99bec
      Mikulas Patocka authored
      The commit 042da426 ("scripts/setlocalversion: simplify the short
      version part") reduces indentation. Unfortunately, it also changes behavior
      in a subtle way - if the user has empty "LOCALVERSION" variable, the plus
      sign is appended to the kernel version. It wasn't appended before.
      
      This patch reverts to the old behavior - we append the plus sign only if
      the LOCALVERSION variable is not set.
      
      Fixes: 042da426 ("scripts/setlocalversion: simplify the short version part")
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarMasahiro Yamada <masahiroy@kernel.org>
      5df99bec
    • Yang Jihong's avatar
      perf sched: Fix record failure when CONFIG_SCHEDSTATS is not set · b0f00855
      Yang Jihong authored
      The tracepoints trace_sched_stat_{wait, sleep, iowait} are not exposed to user
      if CONFIG_SCHEDSTATS is not set, "perf sched record" records the three events.
      As a result, the command fails.
      
      Before:
      
        #perf sched record sleep 1
        event syntax error: 'sched:sched_stat_wait'
                             \___ unknown tracepoint
      
        Error:  File /sys/kernel/tracing/events/sched/sched_stat_wait not found.
        Hint:   Perhaps this kernel misses some CONFIG_ setting to enable this feature?.
      
        Run 'perf list' for a list of valid events
      
         Usage: perf record [<options>] [<command>]
            or: perf record [<options>] -- <command> [<options>]
      
            -e, --event <event>   event selector. use 'perf list' to list available events
      
      Solution:
        Check whether schedstat tracepoints are exposed. If no, these events are not recorded.
      
      After:
        # perf sched record sleep 1
        [ perf record: Woken up 1 times to write data ]
        [ perf record: Captured and wrote 0.163 MB perf.data (1091 samples) ]
        # perf sched report
        run measurement overhead: 4736 nsecs
        sleep measurement overhead: 9059979 nsecs
        the run test took 999854 nsecs
        the sleep test took 8945271 nsecs
        nr_run_events:        716
        nr_sleep_events:      785
        nr_wakeup_events:     0
        ...
        ------------------------------------------------------------
      
      Fixes: 2a09b5de ("sched/fair: do not expose some tracepoints to user if CONFIG_SCHEDSTATS is not set")
      Signed-off-by: default avatarYang Jihong <yangjihong1@huawei.com>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
      Cc: Yafang Shao <laoar.shao@gmail.com>
      Link: http://lore.kernel.org/lkml/20210713112358.194693-1-yangjihong1@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      b0f00855
    • Yang Jihong's avatar
      perf probe: Fix add event failure when running 32-bit perf in a 64-bit kernel · 22a66551
      Yang Jihong authored
      The "address" member of "struct probe_trace_point" uses long data type.
      If kernel is 64-bit and perf program is 32-bit, size of "address"
      variable is 32 bits.
      
      As a result, upper 32 bits of address read from kernel are truncated, an
      error occurs during address comparison in kprobe_warn_out_range().
      
      Before:
      
        # perf probe -a schedule
        schedule is out of .text, skip it.
          Error: Failed to add events.
      
      Solution:
        Change data type of "address" variable to u64 and change corresponding
      address printing and value assignment.
      
      After:
      
        # perf.new.new probe -a schedule
        Added new event:
          probe:schedule       (on schedule)
      
        You can now use it in all perf tools, such as:
      
                perf record -e probe:schedule -aR sleep 1
      
        # perf probe -l
          probe:schedule       (on schedule@kernel/sched/core.c)
        # perf record -e probe:schedule -aR sleep 1
        [ perf record: Woken up 1 times to write data ]
        [ perf record: Captured and wrote 0.156 MB perf.data (1366 samples) ]
        # perf report --stdio
        # To display the perf.data header info, please use --header/--header-only options.
        #
        #
        # Total Lost Samples: 0
        #
        # Samples: 1K of event 'probe:schedule'
        # Event count (approx.): 1366
        #
        # Overhead  Command          Shared Object      Symbol
        # ........  ...............  .................  ............
        #
             6.22%  migration/0      [kernel.kallsyms]  [k] schedule
             6.22%  migration/1      [kernel.kallsyms]  [k] schedule
             6.22%  migration/2      [kernel.kallsyms]  [k] schedule
             6.22%  migration/3      [kernel.kallsyms]  [k] schedule
             6.15%  migration/10     [kernel.kallsyms]  [k] schedule
             6.15%  migration/11     [kernel.kallsyms]  [k] schedule
             6.15%  migration/12     [kernel.kallsyms]  [k] schedule
             6.15%  migration/13     [kernel.kallsyms]  [k] schedule
             6.15%  migration/14     [kernel.kallsyms]  [k] schedule
             6.15%  migration/15     [kernel.kallsyms]  [k] schedule
             6.15%  migration/4      [kernel.kallsyms]  [k] schedule
             6.15%  migration/5      [kernel.kallsyms]  [k] schedule
             6.15%  migration/6      [kernel.kallsyms]  [k] schedule
             6.15%  migration/7      [kernel.kallsyms]  [k] schedule
             6.15%  migration/8      [kernel.kallsyms]  [k] schedule
             6.15%  migration/9      [kernel.kallsyms]  [k] schedule
             0.22%  rcu_sched        [kernel.kallsyms]  [k] schedule
        ...
        #
        # (Cannot load tips.txt file, please install perf!)
        #
      Signed-off-by: default avatarYang Jihong <yangjihong1@huawei.com>
      Acked-by: default avatarMasami Hiramatsu <mhiramat@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Frank Ch. Eigler <fche@redhat.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Jianlin Lv <jianlin.lv@arm.com>
      Cc: Jin Yao <yao.jin@linux.intel.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Li Huafei <lihuafei1@huawei.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
      Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
      Link: http://lore.kernel.org/lkml/20210715063723.11926-1-yangjihong1@huawei.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      22a66551
    • Riccardo Mancini's avatar
      perf data: Close all files in close_dir() · d4b3eedc
      Riccardo Mancini authored
      When using 'perf report' in directory mode, the first file is not closed
      on exit, causing a memory leak.
      
      The problem is caused by the iterating variable never reaching 0.
      
      Fixes: 14552063 ("perf data: Add perf_data__(create_dir|close_dir) functions")
      Signed-off-by: default avatarRiccardo Mancini <rickyman7@gmail.com>
      Acked-by: default avatarNamhyung Kim <namhyung@kernel.org>
      Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
      Cc: Ian Rogers <irogers@google.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Zhen Lei <thunder.leizhen@huawei.com>
      Link: http://lore.kernel.org/lkml/20210716141122.858082-1-rickyman7@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      d4b3eedc
    • Riccardo Mancini's avatar
      perf probe-file: Delete namelist in del_events() on the error path · e0fa7ab4
      Riccardo Mancini authored
      ASan reports some memory leaks when running:
      
        # perf test "42: BPF filter"
      
      This second leak is caused by a strlist not being dellocated on error
      inside probe_file__del_events.
      
      This patch adds a goto label before the deallocation and makes the error
      path jump to it.
      Signed-off-by: default avatarRiccardo Mancini <rickyman7@gmail.com>
      Fixes: e7895e42 ("perf probe: Split del_perf_probe_events()")
      Cc: Ian Rogers <irogers@google.com>
      Cc: Jiri Olsa <jolsa@redhat.com>
      Cc: Mark Rutland <mark.rutland@arm.com>
      Cc: Namhyung Kim <namhyung@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Link: http://lore.kernel.org/lkml/174963c587ae77fa108af794669998e4ae558338.1626343282.git.rickyman7@gmail.comSigned-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
      e0fa7ab4
  4. 17 Jul, 2021 9 commits
    • Linus Torvalds's avatar
      Merge tag 'soc-fixes-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc · 1d67c8d9
      Linus Torvalds authored
      Pull ARM SoC fixes from Arnd Bergmann:
       "Here are the patches for this week that came as the fallout of the
        merge window:
      
         - Two fixes for the NVidia memory controller driver
      
         - multiple defconfig files get patched to turn CONFIG_FB back on
           after that is no longer selected by CONFIG_DRM
      
         - ffa and scmpi firmware drivers fixes, mostly addressing compiler
           and documentation warnings
      
         - Platform specific fixes for device tree files on ASpeed, Renesas
           and NVidia SoC, mostly for recent regressions.
      
         - A workaround for a regression on the USB PHY with devlink when the
           usb-nop-xceiv driver is not available until the rootfs is mounted.
      
         - Device tree compiler warnings in Arm Versatile-AB"
      
      * tag 'soc-fixes-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (35 commits)
        ARM: dts: versatile: Fix up interrupt controller node names
        ARM: multi_v7_defconfig: Make NOP_USB_XCEIV driver built-in
        ARM: configs: Update u8500_defconfig
        ARM: configs: Update Vexpress defconfig
        ARM: configs: Update Versatile defconfig
        ARM: configs: Update RealView defconfig
        ARM: configs: Update Integrator defconfig
        arm: Typo s/PCI_IXP4XX_LEGACY/IXP4XX_PCI_LEGACY/
        firmware: arm_scmi: Fix range check for the maximum number of pending messages
        firmware: arm_scmi: Avoid padding in sensor message structure
        firmware: arm_scmi: Fix kernel doc warnings about return values
        firmware: arm_scpi: Fix kernel doc warnings
        firmware: arm_scmi: Fix kernel doc warnings
        ARM: shmobile: defconfig: Restore graphical consoles
        firmware: arm_ffa: Fix a possible ffa_linux_errmap buffer overflow
        firmware: arm_ffa: Fix the comment style
        firmware: arm_ffa: Simplify probe function
        firmware: arm_ffa: Ensure drivers provide a probe function
        firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow
        firmware: arm_scmi: Ensure drivers provide a probe function
        ...
      1d67c8d9
    • Linus Torvalds's avatar
      Revert "mm/slub: use stackdepot to save stack trace in objects" · ae14c63a
      Linus Torvalds authored
      This reverts commit 78869146.
      
      It's not clear why, but it causes unexplained problems in entirely
      unrelated xfs code.  The most likely explanation is some slab
      corruption, possibly triggered due to CONFIG_SLUB_DEBUG_ON.  See [1].
      
      It ends up having a few other problems too, like build errors on
      arch/arc, and Geert reporting it using much more memory on m68k [3] (it
      probably does so elsewhere too, but it is probably just more noticeable
      on m68k).
      
      The architecture issues (both build and memory use) are likely just
      because this change effectively force-enabled STACKDEPOT (along with a
      very bad default value for the stackdepot hash size).  But together with
      the xfs issue, this all smells like "this commit was not ready" to me.
      
      Link: https://lore.kernel.org/linux-xfs/YPE3l82acwgI2OiV@infradead.org/ [1]
      Link: https://lore.kernel.org/lkml/202107150600.LkGNb4Vb-lkp@intel.com/ [2]
      Link: https://lore.kernel.org/lkml/CAMuHMdW=eoVzM1Re5FVoEN87nKfiLmM2+Ah7eNu2KXEhCvbZyA@mail.gmail.com/ [3]
      Reported-by: default avatarChristoph Hellwig <hch@infradead.org>
      Reported-by: default avatarkernel test robot <lkp@intel.com>
      Reported-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Randy Dunlap <rdunlap@infradead.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      ae14c63a
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 5d766d55
      Linus Torvalds authored
      Pull SCSI fixes from James Bottomley:
       "One core fix for an oops which can occur if the error handling thread
        fails to start for some reason and the driver is removed.
      
        The other fixes are all minor ones in drivers"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: ufs: core: Add missing host_lock in ufshcd_vops_setup_xfer_req()
        scsi: mpi3mr: Fix W=1 compilation warnings
        scsi: pm8001: Clean up kernel-doc and comments
        scsi: zfcp: Report port fc_security as unknown early during remote cable pull
        scsi: core: Fix bad pointer dereference when ehandler kthread is invalid
        scsi: fas216: Fix a build error
        scsi: core: Fix the documentation of the scsi_execute() time parameter
      5d766d55
    • Linus Torvalds's avatar
      Merge tag '5.14-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6 · 44cb60b4
      Linus Torvalds authored
      Pull cifs fixes from Steve French:
       "Eight cifs/smb3 fixes, including three for stable.
      
        Three are DFS related fixes, and two to fix problems pointed out by
        static checkers"
      
      * tag '5.14-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
        cifs: do not share tcp sessions of dfs connections
        SMB3.1.1: fix mount failure to some servers when compression enabled
        cifs: added WARN_ON for all the count decrements
        cifs: fix missing null session check in mount
        cifs: handle reconnect of tcon when there is no cached dfs referral
        cifs: fix the out of range assignment to bit fields in parse_server_interfaces
        cifs: Do not use the original cruid when following DFS links for multiuser mounts
        cifs: use the expiry output of dns_query to schedule next resolution
      44cb60b4
    • Linus Torvalds's avatar
      Merge tag 'linux-kselftest-kunit-fixes-5.14-rc2' of... · ccbb22b9
      Linus Torvalds authored
      Merge tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
      
      Pull kunit fixes from Shuah Khan:
       "Fixes to kunit tool and documentation:
      
         - fix asserts on older python versions
      
         - fixes to misleading error messages when TAP header format is
           incorrect or when file is missing
      
         - documentation fix: drop obsolete information about uml_abort
           coverage
      
         - remove unnecessary annotations"
      
      * tag 'linux-kselftest-kunit-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
        kunit: tool: Assert the version requirement
        kunit: tool: remove unnecessary "annotations" import
        Documentation: kunit: drop obsolete note about uml_abort for coverage
        kunit: tool: Fix error messages for cases of no tests and wrong TAP header
      ccbb22b9
    • Linus Torvalds's avatar
      Merge tag 'linux-kselftest-fixes-5.14-rc2' of... · 00397e74
      Linus Torvalds authored
      Merge tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
      
      Pull kselftest fix from Shuah Khan:
       "A fix to memory-hotplug hot-remove test to stop spamming logs with
        dump_page() entries and slowing the system down to a crawl"
      
      * tag 'linux-kselftest-fixes-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
        selftests: memory-hotplug: avoid spamming logs with dump_page(), ratio limit hot-remove error test
      00397e74
    • Linus Torvalds's avatar
      Merge tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace · 3fdacf40
      Linus Torvalds authored
      Pull tracing fix from Steven Rostedt:
       "Fix the histogram logic from possibly crashing the kernel
      
        Working on the histogram code, I found that if you dereference a char
        pointer in a trace event that happens to point to user space, it can
        crash the kernel, as it does no checks of that pointer. I have code
        coming that will do this better, so just remove this ability to treat
        character pointers in trace events as stings in the histogram"
      
      * tag 'trace-v5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
        tracing: Do not reference char * as a string in histograms
      3fdacf40
    • Linus Torvalds's avatar
      Merge tag 'devicetree-fixes-for-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux · d980cc06
      Linus Torvalds authored
      Pull devicetree fixes from Rob Herring:
      
       - Drop 'resets' as required on renesas,du
      
       - Moving of fixed string patterns for 'properties' instead of
         'patternProperties'
      
       - Drop more redundant minItems/maxItems that we merged in the merge
         window
      
       - Indentation warning fix for sja1105
      
      * tag 'devicetree-fixes-for-5.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
        dt-bindings: display: renesas,du: Make resets optional on R-Car H1
        dt-bindings: Move fixed string 'patternProperties' to 'properties'
        dt-bindings: More dropping redundant minItems/maxItems
        dt-bindings: net: dsa: sja1105: Fix indentation warnings
      d980cc06
    • Linus Torvalds's avatar
      Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux · 5f06a790
      Linus Torvalds authored
      Pull arm64 fixes from Will Deacon:
       "The bulk of the diffstat consists of changes to our uaccess routines
        so that they fall back to bytewise copying prior to reporting complete
        failure when the initial (multi-byte) access faults.
      
        However, the most disappointing change here is that we've had to bump
        ARCH_DMA_MINALIGN back to 128 bytes thanks to Qualcomm's "Kryo" CPU,
        which ended up in the MSM8996 mobile SoC. Still, at least we're now
        aware of this design and one of the hardware designers confirmed the
        L2 cacheline size for us.
      
        Summary:
      
         - Fix instrumentation annotations for entry code
      
         - Ensure kernel MTE state is restored correctly on resume from suspend
      
         - Fix MTE fault from new strlen() routine
      
         - Fallback to byte-wise accesses on initial uaccess fault
      
         - Bump Clang requirement for BTI
      
         - Revert ARCH_DMA_MINALIGN back to 128 bytes (shakes fist at Qualcomm)"
      
      * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
        arm64: entry: fix KCOV suppression
        arm64: entry: add missing noinstr
        arm64: mte: fix restoration of GCR_EL1 from suspend
        arm64: Avoid premature usercopy failure
        arm64: Restrict ARM64_BTI_KERNEL to clang 12.0.0 and newer
        Revert "arm64: cache: Lower ARCH_DMA_MINALIGN to 64 (L1_CACHE_BYTES)"
        arm64: Add missing header <asm/smp.h> in two files
        arm64: fix strlen() with CONFIG_KASAN_HW_TAGS
      5f06a790
  5. 16 Jul, 2021 11 commits