linux-toradex.git/include/trace/events, branch v5.12-rc5

workqueue/tracing: Copy workqueue name to buffer in trace event

2021-03-18T16:57:37+00:00

The trace event "workqueue_queue_work" references an unsafe string in
dereferencing the name of the workqueue. As the name is allocated, it
could later be freed, and the pointer to that string could stay on the
tracing buffer. If the trace buffer is read after the string is freed, it
will reference an unsafe pointer.

I added a new verifier to make sure that all strings referenced in the
output of the trace buffer is safe to read and this triggered on the
workqueue_queue_work trace event:

workqueue_queue_work: work struct=00000000b2b235c7 function=gc_worker workqueue=(0xffff888100051160:events_power_efficient)[UNSAFE-MEMORY] req_cpu=256 cpu=1
workqueue_queue_work: work struct=00000000c344caec function=flush_to_ldisc workqueue=(0xffff888100054d60:events_unbound)[UNSAFE-MEMORY] req_cpu=256 cpu=4294967295
workqueue_queue_work: work struct=00000000b2b235c7 function=gc_worker workqueue=(0xffff888100051160:events_power_efficient)[UNSAFE-MEMORY] req_cpu=256 cpu=1
workqueue_queue_work: work struct=000000000b238b3f function=vmstat_update workqueue=(0xffff8881000c3760:mm_percpu_wq)[UNSAFE-MEMORY] req_cpu=1 cpu=1

Also, if this event is read via a user space application like perf or
trace-cmd, the name would only be an address and useless information:

workqueue_queue_work: work struct=0xffff953f80b4b918 function=disk_events_workfn workqueue=ffff953f8005d378 req_cpu=8192 cpu=5

Cc: Zqiang 
Cc: Tejun Heo 
Fixes: 7bf9c4a88e3e3 ("workqueue: tracing the name of the workqueue instead of it's address")
Signed-off-by: Steven Rostedt (VMware)

Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block

2021-02-28T19:23:38+00:00

Pull more block updates from Jens Axboe:
 "A few stragglers (and one due to me missing it originally), and fixes
  for changes in this merge window mostly. In particular:

   - blktrace cleanups (Chaitanya, Greg)

   - Kill dead blk_pm_* functions (Bart)

   - Fixes for the bio alloc changes (Christoph)

   - Fix for the partition changes (Christoph, Ming)

   - Fix for turning off iopoll with polled IO inflight (Jeffle)

   - nbd disconnect fix (Josef)

   - loop fsync error fix (Mauricio)

   - kyber update depth fix (Yang)

   - max_sectors alignment fix (Mikulas)

   - Add bio_max_segs helper (Matthew)"

* tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block: (21 commits)
  block: Add bio_max_segs
  blktrace: fix documentation for blk_fill_rw()
  block: memory allocations in bounce_clone_bio must not fail
  block: remove the gfp_mask argument to bounce_clone_bio
  block: fix bounce_clone_bio for passthrough bios
  block-crypto-fallback: use a bio_set for splitting bios
  block: fix logging on capacity change
  blk-settings: align max_sectors on "logical_block_size" boundary
  block: reopen the device in blkdev_reread_part
  block: don't skip empty device in in disk_uevent
  blktrace: remove debugfs file dentries from struct blk_trace
  nbd: handle device refs for DESTROY_ON_DISCONNECT properly
  kyber: introduce kyber_depth_updated()
  loop: fix I/O error on fsync() in detached loop devices
  block: fix potential IO hang when turning off io_poll
  block: get rid of the trace rq insert wrapper
  blktrace: fix blk_rq_merge documentation
  blktrace: fix blk_rq_issue documentation
  blktrace: add blk_fill_rwbs documentation comment
  block: remove superfluous param in blk_fill_rwbs()
  ...

Merge tag 'trace-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2021-02-26T18:14:18+00:00

Pull tracing fixes from Steven Rostedt:
 "Two fixes:

   - Fix an unsafe printf string usage in a kmem trace event

   - Fix spelling in output from the latency-collector tool"

* tag 'trace-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/tools: fix a couple of spelling mistakes
  mm, tracing: Fix kmem_cache_free trace event to not print stale pointers

Merge branch 'akpm' (patches from Andrew)

2021-02-26T17:50:09+00:00

Merge more updates from Andrew Morton:
 "118 patches:

   - The rest of MM.

     Includes kfence - another runtime memory validator. Not as thorough
     as KASAN, but it has unmeasurable overhead and is intended to be
     usable in production builds.

   - Everything else

  Subsystems affected by this patch series: alpha, procfs, sysctl,
  misc, core-kernel, MAINTAINERS, lib, bitops, checkpatch, init,
  coredump, seq_file, gdb, ubsan, initramfs, and mm (thp, cma,
  vmstat, memory-hotplug, mlock, rmap, zswap, zsmalloc, cleanups,
  kfence, kasan2, and pagemap2)"

* emailed patches from Andrew Morton : (118 commits)
  MIPS: make userspace mapping young by default
  initramfs: panic with memory information
  ubsan: remove overflow checks
  kgdb: fix to kill breakpoints on initmem after boot
  scripts/gdb: fix list_for_each
  x86: fix seq_file iteration for pat/memtype.c
  seq_file: document how per-entry resources are managed.
  fs/coredump: use kmap_local_page()
  init/Kconfig: fix a typo in CC_VERSION_TEXT help text
  init: clean up early_param_on_off() macro
  init/version.c: remove Version_ symbol
  checkpatch: do not apply "initialise globals to 0" check to BPF progs
  checkpatch: don't warn about colon termination in linker scripts
  checkpatch: add kmalloc_array_node to unnecessary OOM message check
  checkpatch: add warning for avoiding .L prefix symbols in assembly files
  checkpatch: improve TYPECAST_INT_CONSTANT test message
  checkpatch: prefer ftrace over function entry/exit printks
  checkpatch: trivial style fixes
  checkpatch: ignore warning designated initializers using NR_CPUS
  checkpatch: improve blank line after declaration test
  ...

tracing: add error_report_end trace point

2021-02-26T17:41:02+00:00

Patch series "Add error_report_end tracepoint to KFENCE and KASAN", v3.

This patchset adds a tracepoint, error_repor_end, that is to be used by
KFENCE, KASAN, and potentially other bug detection tools, when they print
an error report.  One of the possible use cases is userspace collection of
kernel error reports: interested parties can subscribe to the tracing
event via tracefs, and get notified when an error report occurs.

This patch (of 3):

Introduce error_report_end tracepoint.  It can be used in debugging tools
like KASAN, KFENCE, etc.  to provide extensions to the error reporting
mechanisms (e.g.  allow tests hook into error reporting, ease error report
collection from production kernels).  Another benefit would be making use
of ftrace for debugging or benchmarking the tools themselves.

Should we need it, the tracepoint name leaves us with the possibility to
introduce a complementary error_report_start tracepoint in the future.

Link: https://lkml.kernel.org/r/20210121131915.1331302-1-glider@google.com
Link: https://lkml.kernel.org/r/20210121131915.1331302-2-glider@google.com
Signed-off-by: Alexander Potapenko 
Suggested-by: Marco Elver 
Cc: Andrey Konovalov 
Cc: Dmitry Vyukov 
Cc: Ingo Molnar 
Cc: Petr Mladek 
Cc: Steven Rostedt 
Cc: Sergey Senozhatsky 
Cc: Greg Kroah-Hartman 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

2021-02-26T17:17:24+00:00

Pull NFS Client Updates from Anna Schumaker:
 "New Features:
   - Support for eager writes, and the write=eager and write=wait mount
     options

- Other Bugfixes and Cleanups:
   - Fix typos in some comments
   - Fix up fall-through warnings for Clang
   - Cleanups to the NFS readpage codepath
   - Remove FMR support in rpcrdma_convert_iovs()
   - Various other cleanups to xprtrdma
   - Fix xprtrdma pad optimization for servers that don't support
     RFC 8797
   - Improvements to rpcrdma tracepoints
   - Fix up nfs4_bitmask_adjust()
   - Optimize sparse writes past the end of files"

* tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (27 commits)
  NFS: Support the '-owrite=' option in /proc/self/mounts and mountinfo
  NFS: Set the stable writes flag when initialising the super block
  NFS: Add mount options supporting eager writes
  NFS: Add support for eager writes
  NFS: 'flags' field should be unsigned in struct nfs_server
  NFS: Don't set NFS_INO_INVALID_XATTR if there is no xattr cache
  NFS: Always clear an invalid mapping when attempting a buffered write
  NFS: Optimise sparse writes past the end of file
  NFS: Fix documenting comment for nfs_revalidate_file_size()
  NFSv4: Fixes for nfs4_bitmask_adjust()
  xprtrdma: Clean up rpcrdma_prepare_readch()
  rpcrdma: Capture bytes received in Receive completion tracepoints
  xprtrdma: Pad optimization, revisited
  rpcrdma: Fix comments about reverse-direction operation
  xprtrdma: Refactor invocations of offset_in_page()
  xprtrdma: Simplify rpcrdma_convert_kvec() and frwr_map()
  xprtrdma: Remove FMR support in rpcrdma_convert_iovs()
  NFS: Add nfs_pageio_complete_read() and remove nfs_readpage_async()
  NFS: Call readpage_async_filler() from nfs_readpage_async()
  NFS: Refactor nfs_readpage() and nfs_readpage_async() to use nfs_readdesc
  ...

mm, tracing: Fix kmem_cache_free trace event to not print stale pointers

2021-02-25T17:49:58+00:00

The update to kmem_cache_free trace event added printing of the slab name in
the trace event. But it only stores the pointer of the name which will be
printed as a string when the event is read some time in the future. This is
dangerous because the name could be freed in the mean time and when reading
the trace event it would try to dereference the string name by the pointer
to the name that has been freed.

Instead, use the trace event helper macros __string(), __assign_str(), and
__get_str() that are for this very case.

Cc: Jacob Wen 
Fixes: 3544de8ee6e4 ("mm, tracing: record slab name for kmem_cache_free()")
Signed-off-by: Steven Rostedt (VMware)

mm/swap.c: don't pass "enum lru_list" to trace_mm_lru_insertion()

2021-02-24T21:38:33+00:00

The parameter is redundant in the sense that it can be extracted
from the "struct page" parameter by page_lru() correctly.

Link: https://lore.kernel.org/linux-mm/20201207220949.830352-5-yuzhao@google.com/
Link: https://lkml.kernel.org/r/20210122220600.906146-5-yuzhao@google.com
Signed-off-by: Yu Zhao 
Reviewed-by: Alex Shi 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Matthew Wilcox 
Cc: Michal Hocko 
Cc: Roman Gushchin 
Cc: Vladimir Davydov 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm, tracing: record slab name for kmem_cache_free()

2021-02-24T21:38:26+00:00

Currently, a trace record generated by the RCU core is as below.

... kmem_cache_free: call_site=rcu_core+0x1fd/0x610 ptr=00000000f3b49a66

It doesn't tell us what the RCU core has freed.

This patch adds the slab name to trace_kmem_cache_free().
The new format is as follows.

... kmem_cache_free: call_site=rcu_core+0x1fd/0x610 ptr=0000000037f79c8d name=dentry
... kmem_cache_free: call_site=rcu_core+0x1fd/0x610 ptr=00000000f78cb7b5 name=sock_inode_cache
... kmem_cache_free: call_site=rcu_core+0x1fd/0x610 ptr=0000000018768985 name=pool_workqueue
... kmem_cache_free: call_site=rcu_core+0x1fd/0x610 ptr=000000006a6cb484 name=radix_tree_node

We can use it to understand what the RCU core is going to free. For
example, some users maybe interested in when the RCU core starts
freeing reclaimable slabs like dentry to reduce memory pressure.

Link: https://lkml.kernel.org/r/20201216072804.8838-1-jian.w.wen@oracle.com
Signed-off-by: Jacob Wen 
Cc: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Cc: Joonsoo Kim 
Cc: Steven Rostedt 
Cc: "Paul E. McKenney" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branch 'for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

2021-02-23T01:06:54+00:00

Pull qorkqueue updates from Tejun Heo:
 "Tracepoint and comment updates only"

* 'for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: Use %s instead of function name
  workqueue: tracing the name of the workqueue instead of it's address
  workqueue: fix annotation for WQ_SYSFS