Remove io_req_tw_post() and io_req_tw_post_queue(), we can use
io_req_task_complete() instead.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b9b73c08022c7f1457023ac841f35c0100e70345.1669203009.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use a more generic io_req_task_complete() in timeout completion
task_work instead of io_req_complete_post().
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/bda1710b58c07bf06107421c2a65c529ea9cdcac.1669203009.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

A preparation patch, make sure we always hold uring_lock around
io_req_complete_failed(). The only place deviating from the rule
is io_cancel_defer_files(), queue a tw instead.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/70760344eadaecf2939287084b9d4ba5c05a6984.1669203009.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

There are pieces of code that may allow iopoll to race filling cqes,
temporarily add spinlocking around posting events.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/84d86b5c117feda075471c5c9e65208e0dccf5d0.1669203009.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

__io_cq_unlock_post() is identical to io_cq_unlock_post(), and
io_cqring_ev_posted() has a single caller so migth as well just inline
it there.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This reverts commit 7fdbc5f0.

This patch dealt with a subset of the real problem, which is a potential
circular dependency on the wakup path for io_uring itself. Outside of
io_uring, eventfd can also trigger this (see details in 03e02acd)
and so can epoll (see details in caf1aeaf). Now that we have a
generic solution to this problem, get rid of the io_uring specific
work-around.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pass in EPOLL_URING_WAKE when signaling eventfd or doing poll related
wakups, so that we can check for a circular event dependency between
eventfd and epoll. If this flag is set when our wakeup handlers are
called, then we know we have a dependency that needs to terminate
multishot requests.

eventfd and epoll are the only such possible dependencies.

Cc: stable@vger.kernel.org # 6.0
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This is identical to eventfd_signal(), but it allows the caller to pass
in a mask to be used for the poll wakeup key. The use case is avoiding
repeated multishot triggers if we have a dependency between eventfd and
io_uring.

If we setup an eventfd context and register that as the io_uring eventfd,
and at the same time queue a multishot poll request for the eventfd
context, then any CQE posted will repeatedly trigger the multishot request
until it terminates when the CQ ring overflows.

In preparation for io_uring detecting this circular dependency, add the
mentioned helper so that io_uring can pass in EPOLL_URING as part of the
poll wakeup key.

Cc: stable@vger.kernel.org # 6.0
[axboe: fold in !CONFIG_EVENTFD fix from Zhang Qilong]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We can have dependencies between epoll and io_uring. Consider an epoll
context, identified by the epfd file descriptor, and an io_uring file
descriptor identified by iofd. If we add iofd to the epfd context, and
arm a multishot poll request for epfd with iofd, then the multishot
poll request will repeatedly trigger and generate events until terminated
by CQ ring overflow. This isn't a desired behavior.

Add EPOLL_URING so that io_uring can pass it in as part of the poll wakeup
key, and io_uring can check for that to detect a potential recursive
invocation.

Cc: stable@vger.kernel.org # 6.0
Signed-off-by: Jens Axboe <axboe@kernel.dk>

There is only one user of __io_req_complete_post(), inline it.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/ef4c9059950a3da5cf68df00f977f1fd13bd9306.1668597569.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

When the target process is dying and so task_work_add() is not allowed
we push all task_work item to the fallback workqueue. Move the part
responsible for moving tw items out of __io_req_task_work_add() into
a separate function. Makes it a bit cleaner and gives the compiler a bit
of extra info.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/e503dab9d7af95470ca6b214c6de17715ae4e748.1668162751.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

__io_req_task_work_add() is huge but marked inline, that makes compilers
to generate lots of garbage. Inline the wrapper caller
io_req_task_work_add() instead.

before and after:
   text    data     bss     dec     hex filename
  47347   16248       8   63603    f873 io_uring/io_uring.o
   text    data     bss     dec     hex filename
  45303   16248       8   61559    f077 io_uring/io_uring.o
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/26dc8c28ca0160e3269ef3e55c5a8b917c4d4450.1668162751.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Previous commit ebc11b6c ("io_uring: clean io-wq callbacks") rename
io_free_work() into io_wq_free_work() for consistency. This patch also
updates relevant comment to avoid misunderstanding.

Fixes: ebc11b6c ("io_uring: clean io-wq callbacks")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Link: https://lore.kernel.org/r/20221110122103.20120-1-linma@zju.edu.cnSigned-off-by: Jens Axboe <axboe@kernel.dk>

Previous commit 13a99017 ("io_uring: remove events caching
atavisms") entirely removes the events caching optimization introduced
by commit 81459350 ("io_uring: cache req->apoll->events in
req->cflags"). Hence the related comment should also be removed to avoid
misunderstanding.

Fixes: 13a99017 ("io_uring: remove events caching atavisms")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Link: https://lore.kernel.org/r/20221110060313.16303-1-linma@zju.edu.cnSigned-off-by: Jens Axboe <axboe@kernel.dk>

With commit aa1df3a3 ("io_uring: fix CQE reordering"), there are
stronger guarantees for overflow ordering. Specifically ensuring that
userspace will not receive out of order receive CQEs. Therefore this is
not needed any more for recv/recvmsg.
Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221107125236.260132-4-dylany@meta.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

This is no longer needed after commit aa1df3a3 ("io_uring: fix CQE
reordering"), since all reordering is now taken care of.

This reverts commit cbd25748 ("io_uring: fix multishot accept
ordering").
Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221107125236.260132-2-dylany@meta.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Running task work when not needed can unnecessarily delay
operations. Specifically IORING_SETUP_DEFER_TASKRUN tries to avoid running
task work until the user requests it. Therefore do not run it in
io_uring_register any more.

The one catch is that io_rsrc_ref_quiesce expects it to have run in order
to process all outstanding references, and so reorder it's loop to do this.
Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20221107123349.4106213-1-dylany@meta.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Fixes two errors:

"ERROR: do not use assignment in if condition
130: FILE: io_uring/net.c:130:
+       if (!(issue_flags & IO_URING_F_UNLOCKED) &&

ERROR: do not use assignment in if condition
599: FILE: io_uring/poll.c:599:
+       } else if (!(issue_flags & IO_URING_F_UNLOCKED) &&"
reported by checkpatch.pl in net.c and poll.c .
Signed-off-by: Xinghui Li <korantli@tencent.com>
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/20221102082503.32236-1-korantwork@gmail.com
[axboe: style tweaks]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

We can also move mm accounting to the extended callbacks. It removes a
few cycles from the hot path including skipping one function call and
setting io_req_task_complete as a callback directly. For user backed I/O
it shouldn't make any difference taking into considering atomic mm
accounting and page pinning.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/1062f270273ad11c1b7b45ec59a6a317533d5e64.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Add custom tw and notif callbacks on top of usual bits also handling zc
reporting. That moves it from the hot path.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/40de4a6409042478e1f35adc4912e23226cb1b5c.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

io_notif_flush() is pretty simple, we can inline it.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/332359e7bd124138dfe51340bbec829c9b265c18.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

Just a simple renaming patch, io_uring_tx_zerocopy_callback() is too
bulky and doesn't follow usual naming style.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/24d78325403ca6dcb1ec4bced1e33cacc9b832a5.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

We're going to have multiple notification tw functions. In preparation
for future changes default the tw callback in advance so later we can
replace it with other versions.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/7acdbea5e20eadd844513320cd454af14ba50f64.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

io_send_zc_prep() sets up notification's rsrc_node when needed, don't
unconditionally install it on notif alloc.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/dbe4875ac33e180b9799d8537a5e27935e82aac4.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

There are multiple users of io_req_task_complete() including zc
notifications, but only read requests use selected buffers. As we
already have an rw specific tw function, move io_put_kbuf() in there.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/94374c7649aaefc3a17808dc4701f25ccd457e25.1667557923.git.asml.silence@gmail.comSigned-off-by: Jens Axboe <axboe@kernel.dk>

It might be useful for applications to detect if a zero copy transfer with
SEND[MSG]_ZC was actually possible or not. The application can fallback to
plain SEND[MSG] in order to avoid the overhead of two cqes per request. Or
it can generate a log message that could indicate to an administrator that
no zero copy was possible and could explain degraded performance.

Cc: stable@vger.kernel.org # 6.1
Link: https://lore.kernel.org/io-uring/fb6a7599-8a9b-15e5-9b64-6cd9d01c6ff4@gmail.com/T/#m2b0d9df94ce43b0e69e6c089bdff0ce6babbdfaaSigned-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/8945b01756d902f5d5b0667f20b957ad3f742e5e.1666895626.git.metze@samba.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pull tracing/probes fixes from Steven Rostedt:

 - Fix possible NULL pointer dereference on trace_event_file in
   kprobe_event_gen_test_exit()

 - Fix NULL pointer dereference for trace_array in
   kprobe_event_gen_test_exit()

 - Fix memory leak of filter string for eprobes

 - Fix a possible memory leak in rethook_alloc()

 - Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case which
   can cause a possible use-after-free

 - Fix warning in eprobe filter creation

 - Fix eprobe filter creation as it picked the wrong event for the
   fields

* tag 'trace-probes-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/eprobe: Fix eprobe filter to make a filter correctly
  tracing/eprobe: Fix warning in filter creation
  kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case
  rethook: fix a potential memleak in rethook_alloc()
  tracing/eprobe: Fix memory leak of filter string
  tracing: kprobe: Fix potential null-ptr-deref on trace_array in kprobe_event_gen_test_exit()
  tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()

Pull tracing fixes from Steven Rostedt:

 - Fix polling to block on watermark like the reads do, as user space
   applications get confused when the select says read is available, and
   then the read blocks

 - Fix accounting of ring buffer dropped pages as it is what is used to
   determine if the buffer is empty or not

 - Fix memory leak in tracing_read_pipe()

 - Fix struct trace_array warning about being declared in parameters

 - Fix accounting of ftrace pages used in output at start up.

 - Fix allocation of dyn_ftrace pages by subtracting one from order
   instead of diving it by 2

 - Static analyzer found a case were a pointer being used outside of a
   NULL check (rb_head_page_deactivate())

 - Fix possible NULL pointer dereference if kstrdup() fails in
   ftrace_add_mod()

 - Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()

 - Fix bad pointer dereference in register_synth_event() on error path

 - Remove unused __bad_type_size() method

 - Fix possible NULL pointer dereference of entry in list 'tr->err_log'

 - Fix NULL pointer deference race if eprobe is called before the event
   setup

* tag 'trace-v6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing: Fix race where eprobes can be called before the event
  tracing: Fix potential null-pointer-access of entry in list 'tr->err_log'
  tracing: Remove unused __bad_type_size() method
  tracing: Fix wild-memory-access in register_synth_event()
  tracing: Fix memory leak in test_gen_synth_cmd() and test_empty_synth_event()
  ftrace: Fix null pointer dereference in ftrace_add_mod()
  ring_buffer: Do not deactivate non-existant pages
  ftrace: Optimize the allocation for mcount entries
  ftrace: Fix the possible incorrect kernel message
  tracing: Fix warning on variable 'struct trace_array'
  tracing: Fix memory leak in tracing_read_pipe()
  ring-buffer: Include dropped pages in counting dirty patches
  tracing/ring-buffer: Have polling block on watermark

The flag that tells the event to call its triggers after reading the event
is set for eprobes after the eprobe is enabled. This leads to a race where
the eprobe may be triggered at the beginning of the event where the record
information is NULL. The eprobe then dereferences the NULL record causing
a NULL kernel pointer bug.

Test for a NULL record to keep this from happening.

Link: https://lore.kernel.org/linux-trace-kernel/20221116192552.1066630-1-rafaelmendsr@gmail.com/
Link: https://lore.kernel.org/linux-trace-kernel/20221117214249.2addbe10@gandalf.local.home

Cc: Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7491e2c4 ("tracing: Add a probe that attaches to trace events")
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reported-by: Rafael Mendonca <rafaelmendsr@gmail.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Pull x86 fixes from Borislav Petkov:

 - Do not hold fpregs lock when inheriting FPU permissions because the
   fpregs lock disables preemption on RT but fpu_inherit_perms() does
   spin_lock_irq(), which, on RT, uses rtmutexes and they need to be
   preemptible.

 - Check the page offset and the length of the data supplied by
   userspace for overflow when specifying a set of pages to add to an
   SGX enclave

* tag 'x86_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Drop fpregs lock before inheriting FPU permissions
  x86/sgx: Add overflow check in sgx_validate_offset_length()

Pull scheduler fixes from Borislav Petkov:

 - Fix a small race on the task's exit path where there's a
   misunderstanding whether the task holds rq->lock or not

 - Prevent processes from getting killed when using deprecated or
   unknown rseq ABI flags in order to be able to fuzz the rseq() syscall
   with syzkaller

* tag 'sched_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix race in task_call_func()
  rseq: Use pr_warn_once() when deprecated/unknown ABI flags are encountered

Pull perf fixes from Borislav Petkov:

 - Fix an intel PT erratum where CPUs do not support single range output
   for more than 4K

 - Fix a NULL ptr dereference which can happen after an NMI interferes
   with the event enabling dance in amd_pmu_enable_all()

 - Free the events array too when freeing uncore contexts on CPU online,
   thereby fixing a memory leak

 - Improve the pending SIGTRAP check

* tag 'perf_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/pt: Fix sampling using single range output
  perf/x86/amd: Fix crash due to race between amd_pmu_enable_all, perf NMI and throttling
  perf/x86/amd/uncore: Fix memory leak for events array
  perf: Improve missing SIGTRAP checking

Pull locking fix from Borislav Petkov:

 - Fix a build error with clang 11

* tag 'locking_urgent_for_v6.1_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking: Fix qspinlock/x86 inline asm error

Pull powerpc fix from Michael Ellerman:

 - Fix writable sections being moved into the rodata region.

Thanks to Nicholas Piggin and Christophe Leroy.

* tag 'powerpc-6.1-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc: Fix writable sections being moved into the rodata region

Pull SCSI fixes from James Bottomley:
 "Five small fixes, all in drivers.

  Most of these are error leg freeing issues, with the only really user
  visible one being the zfcp fix"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: iscsi: Fix possible memory leak when device_register() failed
  scsi: zfcp: Fix double free of FSF request when qdio send fails
  scsi: scsi_debug: Fix possible UAF in sdebug_add_host_helper()
  scsi: target: tcm_loop: Fix possible name leak in tcm_loop_setup_hba_bus()
  scsi: mpi3mr: Suppress command reply debug prints

Pull iommu fixes from Joerg Roedel:

 - Preset accessed bits in Intel VT-d page-directory entries to avoid
   hardware error

 - Set supervisor bit only when Intel IOMMU has the SRS capability

* tag 'iommu-fixes-v6.1-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/vt-d: Set SRE bit only when hardware has SRS cap
  iommu/vt-d: Preset Access bit for IOVA in FL non-leaf paging entries

Merge tag 'kbuild-fixes-v6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Update MAINTAINERS with Nathan and Nicolas as new Kbuild reviewers

 - Increment the debian revision for deb-pkg builds

* tag 'kbuild-fixes-v6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Restore .version auto-increment behaviour for Debian packages
  MAINTAINERS: Add linux-kbuild's patchwork
  MAINTAINERS: Remove Michal Marek from Kbuild maintainers
  MAINTAINERS: Add Nathan and Nicolas to Kbuild reviewers

Pull cifs fixes from Steve French:

 - two missing and one incorrect return value checks

 - fix leak on tlink mount failure

* tag '6.1-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: add check for returning value of SMB2_set_info_init
  cifs: Fix wrong return value checking when GETFLAGS
  cifs: add check for returning value of SMB2_close_init
  cifs: Fix connections leak when tlink setup failed

SRS cap is the hardware cap telling if the hardware IOMMU can support
requests seeking supervisor privilege or not. SRE bit in scalable-mode
PASID table entry is treated as Reserved(0) for implementation not
supporting SRS cap.

Checking SRS cap before setting SRE bit can avoid the non-recoverable
fault of "Non-zero reserved field set in PASID Table Entry" caused by
setting SRE bit while there is no SRS cap support. The fault messages
look like below:

 DMAR: DRHD: handling fault status reg 2
 DMAR: [DMA Read NO_PASID] Request device [00:0d.0] fault addr 0x1154e1000
       [fault reason 0x5a]
       SM: Non-zero reserved field set in PASID Table Entry

Fixes: 6f7db75e ("iommu/vt-d: Add second level page table interface")
Cc: stable@vger.kernel.org
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20221115070346.1112273-1-tina.zhang@intel.comSigned-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20221116051544.26540-3-baolu.lu@linux.intel.comSigned-off-by: Joerg Roedel <jroedel@suse.de>