There is no need to print any debug messages after failure to
allocate memory, because kernel will print OOM dumps anyway.

Together with removal of these messages, remove useless goto jumps.

Fixes: 5bf944f2 ("RDMA/rxe: Add error messages")
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/all/ea43486f-43dd-4054-b1d5-3a0d202be621@kili.mountain
Link: https://lore.kernel.org/r/d3cedf723b84e73e8062a67b7489d33802bafba2.1680113597.git.leon@kernel.orgReviewed-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Remove the tasklet call in rxe_cq.c and also the is_dying in the
cq struct. There is no reason for the rxe driver to defer the call
to the cq completion handler by scheduling a tasklet. rxe_cq_post()
is not called in a hard irq context.

The rxe driver currently is incorrect because the tasklet call is
made without protecting the cq pointer with a reference from having
the underlying memory freed before the deferred routine is called.
Executing the comp_handler inline fixes this problem.

Fixes: 8700e3e7 ("Soft RoCE driver")
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Link: https://lore.kernel.org/r/20230327215643.10410-1-rpearsonhpe@gmail.comAcked-by: Zhu Yanjun <zyjzyj2000@gmail.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

clang with W=1 reports
drivers/infiniband/hw/ocrdma/ocrdma_verbs.c:1592:6: error: variable
  'discard_cnt' set but not used [-Werror,-Wunused-but-set-variable]
        int discard_cnt = 0;
            ^
This variable is not used so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20230326120959.1351948-1-trix@redhat.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

clang with W=1 reports
drivers/infiniband/hw/bnxt_re/qplib_fp.c:303:6: error: variable
  'num_srqne_processed' set but not used [-Werror,-Wunused-but-set-variable]
        int num_srqne_processed = 0;
            ^
drivers/infiniband/hw/bnxt_re/qplib_fp.c:304:6: error: variable
  'num_cqne_processed' set but not used [-Werror,-Wunused-but-set-variable]
        int num_cqne_processed = 0;
            ^
These variables are not used so remove them.
Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20230325140559.1336056-1-trix@redhat.comAcked-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

Remove pci_clear_master to simplify the code,
the bus-mastering is also cleared in do_pci_disable_device,
like this:
./drivers/pci/pci.c:2197
static void do_pci_disable_device(struct pci_dev *dev)
{
	u16 pci_command;

	pci_read_config_word(dev, PCI_COMMAND, &pci_command);
	if (pci_command & PCI_COMMAND_MASTER) {
		pci_command &= ~PCI_COMMAND_MASTER;
		pci_write_config_word(dev, PCI_COMMAND, pci_command);
	}

	pcibios_disable_device(dev);
}.
And dev->is_busmaster is set to 0 in pci_disable_device.
Signed-off-by: Cai Huoqing <cai.huoqing@linux.dev>
Link: https://lore.kernel.org/r/20230323115742.13836-1-cai.huoqing@linux.devSigned-off-by: Leon Romanovsky <leon@kernel.org>

Previously for switchdev only per device counters were supported.

Currently we allocate counters for switchdev per port, which also
includes the ports that belong to VF representors in order to expose
them to users through the rdma tool, allowing the host to track the VFs
statistics through their representors counters.
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Link: https://lore.kernel.org/r/ea31e1103c125cd27931ba213f307cde30d2eaed.1679566038.git.leon@kernel.orgSigned-off-by: Leon Romanovsky <leon@kernel.org>

* mlx5-next:
  net/mlx5: Introduce other vport query for Q-counters

These new fields in QUERY_Q_COUNTER command allow us to access
another vport counters during the query command, which is specially
useful to query representor vports.

In addition also add the required caps to check if this capability
is actually supported.
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://lore.kernel.org/r/75c73a4a0e60f18c37b35a4a11ca2e2415e4a6f3.1679566038.git.leon@kernel.orgSigned-off-by: Leon Romanovsky <leon@kernel.org>

Add resize_cq verb support for user space CQs. Resize operation for
kernel CQs are not supported now.

Driver should free the current CQ only after user library polls
for all the completions and switch to new CQ. So after the resize_cq
is returned from the driver, user library polls for existing completions
and store it as temporary data. Once library reaps all completions in the
current CQ, it invokes the ibv_cmd_poll_cq to inform the driver about
the resize_cq completion. Adding a check for user CQs in driver's
poll_cq and complete the resize operation for user CQs.
Updating uverbs_cmd_mask with poll_cq to support this.
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Link: https://lore.kernel.org/r/1678868215-23626-1-git-send-email-selvin.xavier@broadcom.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

Hardware's page size is 4096, but the kernel's page size may vary. Driver
should use hardware's page size when communicating with hardware.

Fixes: 15505577 ("RDMA/erdma: Add verbs implementation")
Link: https://lore.kernel.org/r/20230307102924.70577-2-chengyou@linux.alibaba.comSigned-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

This patch is a major rewrite of the tasklet routines in rxe_task.c.  The
main motivation for this is the realization that the code violates the
safety of the qp pointer by correct reference counting.  When a tasklet is
scheduled from a verbs API the calling thread has a valid reference to the
qp and schedules the tasklet to run at a later time carrying a pointer to
the qp. Once the calling code returns however the qp can be destroyed at
any time. In order to correct this a reference to the qp must be taken
when the task is scheduled and held until it finishes running. This is
complicated by the tasklet library not alwys running a task that is
scheduled depending on whether someone else has scheduled it.

This patch moves the logic for deciding whether to run or schedule a task
outside of do_task() and guarantees that there is only one copy of the
task scheduled or running at a time.

Secondly the separate flags controlling teardown and draining of the task
are included in the task state machine and all references to the state are
protected by spinlocks to avoid consistency and memory barrier issues.

Link: https://lore.kernel.org/r/20230304174533.11296-9-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Replace rxe_run_task() by rxe_sched_task() when tasks call each other.
These are not performance critical and mainly involve error paths but they
run the risk of causing deadlocks.

Link: https://lore.kernel.org/r/20230304174533.11296-8-rpearsonhpe@gmail.comSigned-off-by: Ian Ziemba <ian.ziemba@hpe.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

The subroutine __rxe_do_task is not thread safe and it has no way to
guarantee that the tasks, which are designed with the assumption that they
are non-reentrant, are not reentered. All of its uses are non-performance
critical.

This patch replaces calls to __rxe_do_task with calls to
rxe_sched_task. It also removes irrelevant or unneeded if tests.

Instead of calling the task machinery a single call to the tasklet
function (rxe_requester, etc.) is sufficient to draing the queues if task
execution has been disabled or stopped.

Together these changes allow the removal of __rxe_do_task.

Link: https://lore.kernel.org/r/20230304174533.11296-7-rpearsonhpe@gmail.comSigned-off-by: Ian Ziemba <ian.ziemba@hpe.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Currently each of the three tasklets requester, completer and responder in
the rxe driver take and release a reference to the qp argument at the
beginning and end of the subroutines. The caller passing in the qp
argument should be responsible for holding a reference to qp so these are
not required. Further doing so breaks the qp cleanup code in
rxe_qp_do_cleanup which calls these routines after all the references have
been dropped so they cannot drain the packet and work request queues as
intended.

In fact if these routines are deferred by calling tasklet_schedule there
is no guarantee that the calling code does have a qp reference.  That is a
bug in rxe_task.c which will be fixed later in this series.

Link: https://lore.kernel.org/r/20230304174533.11296-6-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Cleanup the handling of qp in the error state, reset state and during
rxe_qp_do_cleanup. Make the same as rxe_resp.c

Link: https://lore.kernel.org/r/20230304174533.11296-5-rpearsonhpe@gmail.comSigned-off-by: Ian Ziemba <ian.ziemba@hpe.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Cleanup the handling of qp in the error state, reset state and during
rxe_qp_do_cleanup. The error state does about the same thing as the others
but has code spread all over.

This patch combines them in a cleaner way.

Link: https://lore.kernel.org/r/20230304174533.11296-4-rpearsonhpe@gmail.comSigned-off-by: Ian Ziemba <ian.ziemba@hpe.com>
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Originally is was thought that the tasklet machinery in rxe_task.c would
be used in other applications but that has not happened for years. This
patch replaces the 'void *arg' by struct 'rxe_qp *qp' in the parameters to
the tasklet calls. This change will have no affect on performance but may
make the code a little clearer.

Link: https://lore.kernel.org/r/20230304174533.11296-2-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

This patch adds error and debug messages so that every interaction
with rdma-core through a verbs API call or a completion error return
will generate at least one error message backed up by debug messages
with more detail.

With dynamic debugging one can follow up after seeing an error message
by turning on the appropriate debug messages.

Link: https://lore.kernel.org/r/20230303221623.8053-5-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Extend the dbg log messages (e.g. rxe_dbg_xxx) to include
err and info types. rxe.c is modified to use these new log
messages as examples.

Link: https://lore.kernel.org/r/20230303221623.8053-4-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Replace the name rxe_dbg with rxe_dbg_dev which better matches
the remaining rxe_dbg_xxx macros for debug messages with a
rxe device parameter. Reuse the name rxe_dbg for debug messages
which do not have a rxe device parameter.

Link: https://lore.kernel.org/r/20230303221623.8053-3-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

'exists' looks like a boolean. This patch replaces it by the
normal name used for the rxe device, 'rxe', which should be a
little less confusing. The second rxe_dbg() message is
incorrect since rxe is known to be NULL and this will cause a
seg fault if this message were ever sent. Replace it by pr_debug
for the moment.

Fixes: c6aba5ea ("RDMA/rxe: Replace pr_xxx by rxe_dbg_xxx in rxe.c")
Link: https://lore.kernel.org/r/20230303221623.8053-2-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

GCC-13 (and Clang)[1] does not like to access a partially allocated
object, since it cannot reason about it for bounds checking.

In this case 140 bytes are allocated for an object of type struct
ib_umad_packet:

        packet = kzalloc(sizeof(*packet) + IB_MGMT_RMPP_HDR, GFP_KERNEL);

However, notice that sizeof(*packet) is only 104 bytes:

struct ib_umad_packet {
        struct ib_mad_send_buf *   msg;                  /*     0     8 */
        struct ib_mad_recv_wc *    recv_wc;              /*     8     8 */
        struct list_head           list;                 /*    16    16 */
        int                        length;               /*    32     4 */

        /* XXX 4 bytes hole, try to pack */

        struct ib_user_mad         mad __attribute__((__aligned__(8))); /*    40    64 */

        /* size: 104, cachelines: 2, members: 5 */
        /* sum members: 100, holes: 1, sum holes: 4 */
        /* forced alignments: 1, forced holes: 1, sum forced holes: 4 */
        /* last cacheline: 40 bytes */
} __attribute__((__aligned__(8)));

and 36 bytes extra bytes are allocated for a flexible-array member in
struct ib_user_mad:

include/rdma/ib_mad.h:
120 enum {
...
123         IB_MGMT_RMPP_HDR = 36,
... }

struct ib_user_mad {
        struct ib_user_mad_hdr     hdr;                  /*     0    64 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        __u64                      data[] __attribute__((__aligned__(8))); /*    64     0 */

        /* size: 64, cachelines: 1, members: 2 */
        /* forced alignments: 1 */
} __attribute__((__aligned__(8)));

So we have sizeof(*packet) + IB_MGMT_RMPP_HDR == 140 bytes

Then the address of the flex-array member (for which only 36 bytes were
allocated) is casted and copied into a pointer to struct ib_rmpp_mad,
which, in turn, is of size 256 bytes:

        rmpp_mad = (struct ib_rmpp_mad *) packet->mad.data;

struct ib_rmpp_mad {
        struct ib_mad_hdr          mad_hdr;              /*     0    24 */
        struct ib_rmpp_hdr         rmpp_hdr;             /*    24    12 */
        u8                         data[220];            /*    36   220 */

        /* size: 256, cachelines: 4, members: 3 */
};

The thing is that those 36 bytes allocated for flex-array member data
in struct ib_user_mad onlly account for the size of both struct ib_mad_hdr
and struct ib_rmpp_hdr, but nothing is left for array u8 data[220].
So, the compiler is legitimately complaining about accessing an object
for which not enough memory was allocated.

Apparently, the only members of struct ib_rmpp_mad that are relevant
(that are actually being used) in function ib_umad_write() are mad_hdr
and rmpp_hdr. So, instead of casting packet->mad.data to
(struct ib_rmpp_mad *) create a new structure

struct ib_rmpp_mad_hdr {
        struct ib_mad_hdr       mad_hdr;
        struct ib_rmpp_hdr      rmpp_hdr;
} __packed;

and cast packet->mad.data to (struct ib_rmpp_mad_hdr *).

Notice that

        IB_MGMT_RMPP_HDR == sizeof(struct ib_rmpp_mad_hdr) == 36 bytes

Refactor the rest of the code, accordingly.

Fix the following warnings seen under GCC-13 and -Warray-bounds:
drivers/infiniband/core/user_mad.c:564:50: warning: array subscript ‘struct ib_rmpp_mad[0]’ is partly outside array bounds of ‘unsigned char[140]’ [-Warray-bounds=]
drivers/infiniband/core/user_mad.c:566:42: warning: array subscript ‘struct ib_rmpp_mad[0]’ is partly outside array bounds of ‘unsigned char[140]’ [-Warray-bounds=]
drivers/infiniband/core/user_mad.c:618:25: warning: array subscript ‘struct ib_rmpp_mad[0]’ is partly outside array bounds of ‘unsigned char[140]’ [-Warray-bounds=]
drivers/infiniband/core/user_mad.c:622:44: warning: array subscript ‘struct ib_rmpp_mad[0]’ is partly outside array bounds of ‘unsigned char[140]’ [-Warray-bounds=]

Link: https://github.com/KSPP/linux/issues/273
Link: https://godbolt.org/z/oYWaGM4Yb [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/ZBpB91qQcB10m3Fw@workSigned-off-by: Leon Romanovsky <leon@kernel.org>

This series from Or changes default of IB out-of-order feature and
allows to the RDMA users to decide if they need to wait for completion
for all segments or it is enough to wait for last segment completion only.

Thanks
Signed-off-by: Leon Romanovsky <leon@kernel.org>

When FW supports ooo by default, enable the cap.
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/00bd14bfb002ed2338de3296bcd9af27d4770b70.1679230449.git.leon@kernel.orgSigned-off-by: Leon Romanovsky <leon@kernel.org>

Set retry_mode to GO_BACK_N when qp is created with INTEGRITY_EN flag
because out-of-order is not supported when doing HW offload of signature
operations.
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/362de42cdc7a541afa5b1fd0ec6ae706061764a2.1679230449.git.leon@kernel.orgSigned-off-by: Leon Romanovsky <leon@kernel.org>

Add needed HW bits for enabling out-of-order by default and
use go_back_n when out-of-order is not needed.
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/75d6dfe263989a05c08c43406132b336ea12d00a.1679230449.git.leon@kernel.orgSigned-off-by: Leon Romanovsky <leon@kernel.org>

Add feature bit to existing device caps field. EFA supports data polling
of 128 bytes blocks.

The flag indicates that the NIC guarentees that a 128 byte aligned block
is written in order, ie that observing the last 8 bits of the block mean
the prior 127 bytes are also written.

It is useful for "last data polling" acceleration techniques.

Link: https://lore.kernel.org/r/20230219081328.10419-1-mrgolin@amazon.comReviewed-by: Yehuda Yitschak <yehuday@amazon.com>
Reviewed-by: Yossi Leybovich <sleybo@amazon.com>
Signed-off-by: Yonatan Nachum <ynachum@amazon.com>
Signed-off-by: Michael Margolin <mrgolin@amazon.com>
Acked-by: Gal Pressman <gal.pressman@linux.dev>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

After necessary configuration, driver should wait hardware finishing
initialization. The wait sets at CMDQ related function though it has
nothing to do with CMDQ. Refactor this part to make code cleaner.
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230322093319.84045-4-chengyou@linux.alibaba.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

Using void * to define EQ doorbell pointer can eliminate unnecessary
casting when performing assignment. Also rename *db_addr* to *db* for a
shorter name.
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230322093319.84045-3-chengyou@linux.alibaba.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

Replace __be32_to_cpu/__cpu_to_be16 with be32_to_cpu/cpu_to_be16.
And use be32_to_cpu_array to copy and swap byte order to hide the
loop.
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Link: https://lore.kernel.org/r/20230322093319.84045-2-chengyou@linux.alibaba.comSigned-off-by: Leon Romanovsky <leon@kernel.org>

Pull tracing fixes from Steven Rostedt:

 - Fix setting affinity of hwlat threads in containers

   Using sched_set_affinity() has unwanted side effects when being
   called within a container. Use set_cpus_allowed_ptr() instead

 - Fix per cpu thread management of the hwlat tracer:
    - Do not start per_cpu threads if one is already running for the CPU
    - When starting per_cpu threads, do not clear the kthread variable
      as it may already be set to running per cpu threads

 - Fix return value for test_gen_kprobe_cmd()

   On error the return value was overwritten by being set to the result
   of the call from kprobe_event_delete(), which would likely succeed,
   and thus have the function return success

 - Fix splice() reads from the trace file that was broken by commit
   36e2c742 ("fs: don't allow splice read/write without explicit
   ops")

 - Remove obsolete and confusing comment in ring_buffer.c

   The original design of the ring buffer used struct page flags for
   tricks to optimize, which was shortly removed due to them being
   tricks. But a comment for those tricks remained

 - Set local functions and variables to static

* tag 'trace-v6.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/hwlat: Replace sched_setaffinity with set_cpus_allowed_ptr
  ring-buffer: remove obsolete comment for free_buffer_page()
  tracing: Make splice_read available again
  ftrace: Set direct_ops storage-class-specifier to static
  trace/hwlat: Do not start per-cpu thread if it is already running
  trace/hwlat: Do not wipe the contents of per-cpu thread data
  tracing/osnoise: set several trace_osnoise.c variables storage-class-specifier to static
  tracing: Fix wrong return in kprobe_event_gen_test.c

There is a problem with the behavior of hwlat in a container,
resulting in incorrect output. A warning message is generated:
"cpumask changed while in round-robin mode, switching to mode none",
and the tracing_cpumask is ignored. This issue arises because
the kernel thread, hwlatd, is not a part of the container, and
the function sched_setaffinity is unable to locate it using its PID.
Additionally, the task_struct of hwlatd is already known.
Ultimately, the function set_cpus_allowed_ptr achieves
the same outcome as sched_setaffinity, but employs task_struct
instead of PID.

Test case:

  # cd /sys/kernel/tracing
  # echo 0 > tracing_on
  # echo round-robin > hwlat_detector/mode
  # echo hwlat > current_tracer
  # unshare --fork --pid bash -c 'echo 1 > tracing_on'
  # dmesg -c

Actual behavior:

[573502.809060] hwlat_detector: cpumask changed while in round-robin mode, switching to mode none

Link: https://lore.kernel.org/linux-trace-kernel/20230316144535.1004952-1-costa.shul@redhat.com

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 0330f7aa ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

The comment refers to mm/slob.c which is being removed. It comes from
commit ed56829c ("ring_buffer: reset buffer page when freeing") and
according to Steven the borrowed code was a page mapcount and mapping
reset, which was later removed by commit e4c2ce82 ("ring_buffer:
allocate buffer page pointer"). Thus the comment is not accurate anyway,
remove it.

Link: https://lore.kernel.org/linux-trace-kernel/20230315142446.27040-1-vbabka@suse.cz

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Reported-by: Mike Rapoport <mike.rapoport@gmail.com>
Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Fixes: e4c2ce82 ("ring_buffer: allocate buffer page pointer")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Since the commit 36e2c742 ("fs: don't allow splice read/write
without explicit ops") is applied to the kernel, splice() and
sendfile() calls on the trace file (/sys/kernel/debug/tracing
/trace) return EINVAL.

This patch restores these system calls by initializing splice_read
in file_operations of the trace file. This patch only enables such
functionalities for the read case.

Link: https://lore.kernel.org/linux-trace-kernel/20230314013707.28814-1-sfoon.kim@samsung.com

Cc: stable@vger.kernel.org
Fixes: 36e2c742 ("fs: don't allow splice read/write without explicit ops")
Signed-off-by: Sung-hun Kim <sfoon.kim@samsung.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Pull tty/serial driver fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 6.3-rc3 to resolve
  some reported issues.

  They include:

   - 8250 driver Kconfig issue pointed out by you that showed up in -rc1

   - qcom-geni serial driver fixes

   - various 8250 driver fixes for reported problems

   - fsl_lpuart driver fixes

   - serdev fix for regression in -rc1

   - vt.c bugfix

  All have been in linux-next for over a week with no reported problems"

* tag 'tty-6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  tty: vt: protect KD_FONT_OP_GET_TALL from unbound access
  serial: qcom-geni: drop bogus uart_write_wakeup()
  serial: qcom-geni: fix mapping of empty DMA buffer
  serial: qcom-geni: fix DMA mapping leak on shutdown
  serial: qcom-geni: fix console shutdown hang
  serdev: Set fwnode for serdev devices
  tty: serial: fsl_lpuart: fix race on RX DMA shutdown
  serial: 8250_pci1xxxx: Disable SERIAL_8250_PCI1XXXX config by default
  serial: 8250_fsl: fix handle_irq locking
  serial: 8250_em: Fix UART port type
  serial: 8250: ASPEED_VUART: select REGMAP instead of depending on it
  tty: serial: fsl_lpuart: skip waiting for transmission complete when UARTCTRL_SBK is asserted
  Revert "tty: serial: fsl_lpuart: adjust SERIAL_FSL_LPUART_CONSOLE config dependency"

Pull char/misc driver fixes from Greg KH:
 "Here are a few small char/misc/other driver subsystem patches to
  resolve reported problems for 6.3-rc3.

  Included in here are:

   - Interconnect driver fixes for reported problems

   - Memory driver fixes for reported problems

   - nvmem core fix

   - firmware driver fix for reported problem

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (23 commits)
  memory: tegra30-emc: fix interconnect registration race
  memory: tegra20-emc: fix interconnect registration race
  memory: tegra124-emc: fix interconnect registration race
  memory: tegra: fix interconnect registration race
  interconnect: exynos: drop redundant link destroy
  interconnect: exynos: fix registration race
  interconnect: exynos: fix node leak in probe PM QoS error path
  interconnect: qcom: msm8974: fix registration race
  interconnect: qcom: rpmh: fix registration race
  interconnect: qcom: rpmh: fix probe child-node error handling
  interconnect: qcom: rpm: fix registration race
  nvmem: core: return -ENOENT if nvmem cell is not found
  firmware: xilinx: don't make a sleepable memory allocation from an atomic context
  interconnect: qcom: rpm: fix probe child-node error handling
  interconnect: qcom: osm-l3: fix registration race
  interconnect: imx: fix registration race
  interconnect: fix provider registration API
  interconnect: fix icc_provider_del() error handling
  interconnect: fix mem leak when freeing nodes
  interconnect: qcom: qcm2290: Fix MASTER_SNOC_BIMC_NRT
  ...

Pull RAS fix from Borislav Petkov:

 - Flush out logged errors immediately after MCA banks configuration
   changes over sysfs have been done instead of waiting until something
   else triggers the workqueue later - another error or the polling
   interval cycle is reached

* tag 'ras_urgent_for_v6.3_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Make sure logged MCEs are processed after sysfs update

Pull perf fixes from Borislav Petkov:

 - Check whether sibling events have been deactivated before adding them
   to groups

 - Update the proper event time tracking variable depending on the event
   type

 - Fix a memory overwrite issue due to using the wrong function argument
   when outputting perf events

* tag 'perf_urgent_for_v6.3_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix check before add_event_to_groups() in perf_group_detach()
  perf: fix perf_event_context->time
  perf/core: Fix perf_output_begin parameter is incorrectly invoked in perf_event_bpf_output

Pull x86 fixes from Borislav Petkov:
 "There's a little bit more 'movement' in there for my taste but it
  needs to happen and should make the code better after it.

   - Check cmdline_find_option()'s return value before further
     processing

   - Clear temporary storage in the resctrl code to prevent access to an
     unexistent MSR

   - Add a simple throttling mechanism to protect the hypervisor from
     potentially malicious SEV guests issuing requests in rapid
     succession.

     In order to not jeopardize the sanity of everyone involved in
     maintaining this code, the request issuing side has received a
     cleanup, split in more or less trivial, small and digestible
     pieces. Otherwise, the code was threatening to become an
     unmaintainable mess.

     Therefore, that cleanup is marked indirectly also for stable so
     that there's no differences between the upstream code and the
     stable variant when it comes down to backporting more there"

* tag 'x86_urgent_for_v6.3_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix use of uninitialized buffer in sme_enable()
  x86/resctrl: Clear staged_config[] before and after it is used
  virt/coco/sev-guest: Add throttling awareness
  virt/coco/sev-guest: Convert the sw_exit_info_2 checking to a switch-case
  virt/coco/sev-guest: Do some code style cleanups
  virt/coco/sev-guest: Carve out the request issuing logic into a helper
  virt/coco/sev-guest: Remove the disable_vmpck label in handle_guest_request()
  virt/coco/sev-guest: Simplify extended guest request handling
  virt/coco/sev-guest: Check SEV_SNP attribute at probe time