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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
36e2c7421f02 ("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
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"
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: 0330f7aa8ee63 ("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>
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
...
In ioctl(KD_FONT_OP_GET_TALL), userland tells through op->height which
vpitch should be used to copy over the font. In con_font_get, we were
not checking that it is within the maximum height value, and thus
userland could make the vc->vc_sw->con_font_get(vc, &font, vpitch);
call possibly overflow the allocated max_font_size bytes, and the
copy_to_user(op->data, font.data, c) call possibly read out of that
allocated buffer.
By checking vpitch against max_font_height, the max_font_size buffer
will always be large enough for the vc->vc_sw->con_font_get(vc, &font,
vpitch) call (since we already prevent loading a font larger than that),
and c = (font.width+7)/8 * vpitch * font.charcount will always remain
below max_font_size.
Fixes: 24d69384bcd3 ("VT: Add KD_FONT_OP_SET/GET_TALL operations")
Reported-by: syzbot+3af17071816b61e807ed@syzkaller.appspotmail.com
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230306094921.tik5ewne4ft6mfpo@begin
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The comment refers to mm/slob.c which is being removed. It comes from
commit ed56829cb319 ("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 e4c2ce82ca27 ("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: e4c2ce82ca27 ("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>
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
Georgi writes:
interconnect fixes for v6.3-rc
This contains a bunch of fixes with the highlight being fixes for a race
condition that could sometimes occur during the interconnect provider
driver registration. There are also fixes for memory overallocation and
a memory leak.
- interconnect: qcom: osm-l3: fix icc_onecell_data allocation
- interconnect: qcom: sm8450: switch to qcom_icc_rpmh_* function
- interconnect: qcom: sm8550: switch to qcom_icc_rpmh_* function
- interconnect: qcom: qcm2290: Fix MASTER_SNOC_BIMC_NRT
- interconnect: fix mem leak when freeing nodes
- interconnect: fix icc_provider_del() error handling
- interconnect: fix provider registration API
- interconnect: imx: fix registration race
- interconnect: qcom: osm-l3: fix registration race
- interconnect: qcom: rpm: fix probe child-node error handling
- interconnect: qcom: rpm: fix registration race
- interconnect: qcom: rpmh: fix probe child-node error handling
- interconnect: qcom: rpmh: fix registration race
- interconnect: qcom: msm8974: fix registration race
- interconnect: exynos: fix node leak in probe PM QoS error path
- interconnect: exynos: fix registration race
- interconnect: exynos: drop redundant link destroy
- memory: tegra: fix interconnect registration race
- memory: tegra124-emc: fix interconnect registration race
- memory: tegra20-emc: fix interconnect registration race
- memory: tegra30-emc: fix interconnect registration race
Signed-off-by: Georgi Djakov <djakov@kernel.org>
* tag 'icc-6.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/djakov/icc: (21 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
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
interconnect: qcom: sm8550: switch to qcom_icc_rpmh_* function
interconnect: qcom: sm8450: switch to qcom_icc_rpmh_* function
...
Drop the bogus uart_write_wakeup() from when setting up a new DMA
transfer, which does not free up any more space in the ring buffer.
Any pending writers will be woken up when the transfer completes.
Cc: stable <stable@kernel.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # sa8540p-ride
Link: https://lore.kernel.org/r/20230307164405.14218-5-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the commit 36e2c7421f02 ("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: 36e2c7421f02 ("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 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
A recent change introduced a flag to queue up errors found during
boot-time polling. These errors will be processed during late init once
the MCE subsystem is fully set up.
A number of sysfs updates call mce_restart() which goes through a subset
of the CPU init flow. This includes polling MCA banks and logging any
errors found. Since the same function is used as boot-time polling,
errors will be queued. However, the system is now past late init, so the
errors will remain queued until another error is found and the workqueue
is triggered.
Call mce_schedule_work() at the end of mce_restart() so that queued
errors are processed.
Fixes: 3bff147b187d ("x86/mce: Defer processing of early errors")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230301221420.2203184-1-yazen.ghannam@amd.com
Prior to commit 5d8e6e6c10a3 ("nvmem: core: add an index parameter to
the cell") of_nvmem_cell_get() would return -ENOENT if the cell wasn't
found. Particularly, if of_property_match_string() returned -EINVAL,
that return code was passed as the index to of_parse_phandle(), which
then detected it as invalid and returned NULL. That led to an return
code of -ENOENT.
With the new code, the negative index will lead to an -EINVAL of
of_parse_phandle_with_optional_args() which pass straight to the
caller and break those who expect an -ENOENT.
Fix it by always returning -ENOENT.
Fixes: 5d8e6e6c10a3 ("nvmem: core: add an index parameter to the cell")
Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Link: https://lore.kernel.org/r/2143916.GUh0CODmnK@steina-w/
Signed-off-by: Michael Walle <michael@walle.cc>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230310094845.139400-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to fail.
Switch to using the new API where the provider is not registered until
after it has been fully initialised.
Fixes: d5ef16ba5fbe ("memory: tegra20: Support interconnect framework")
Cc: stable@vger.kernel.org # 5.11
Cc: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-21-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Make sure that there is data in the ring buffer before trying to set up
a zero-length DMA transfer.
This specifically fixes the following warning when unmapping the empty
buffer on the sc8280xp-crd:
WARNING: CPU: 0 PID: 138 at drivers/iommu/dma-iommu.c:1046 iommu_dma_unmap_page+0xbc/0xd8
...
Call trace:
iommu_dma_unmap_page+0xbc/0xd8
dma_unmap_page_attrs+0x30/0x1c8
geni_se_tx_dma_unprep+0x28/0x38
qcom_geni_serial_isr+0x358/0x75c
Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Cc: stable <stable@kernel.org>
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Tested-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Tested-by: Andrew Halaney <ahalaney@redhat.com> # sa8540p-ride
Link: https://lore.kernel.org/r/20230307164405.14218-4-johan+linaro@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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