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The cpuhp state name given to cpuhp_setup_state() is "fgraph_idle_init"
which doesn't really conform to the names that are used for cpu hotplug
setups. Instead rename it to "fgraph:online" to be in line with other
states.
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20241024222944.473d88c5@rorschach.local.home
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 2c02f7375e658 ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Use guard(mutex)() to acquire and automatically release ftrace_lock,
fixing the issue of not unlocking when calling cpuhp_setup_state()
fails.
Fixes smatch warning:
kernel/trace/fgraph.c:1317 register_ftrace_graph() warn: inconsistent returns '&ftrace_lock'.
Link: https://lore.kernel.org/20241024155917.1019580-1-lihuafei1@huawei.com
Fixes: 2c02f7375e65 ("fgraph: Use CPU hotplug mechanism to initialize idle shadow stacks")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/r/202410220121.wxg0olfd-lkp@intel.com/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Li Huafei <lihuafei1@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The ret_stack_list is an array of ret_stack shadow stacks for the function
graph usage. When the first function graph is enabled, all tasks in the
system get a shadow stack. The ret_stack_list is a 32 element array of
pointers to these shadow stacks. It allocates the shadow stack in batches
(32 stacks at a time), assigns them to running tasks, and continues until
all tasks are covered.
When the function graph shadow stack changed from an array of
ftrace_ret_stack structures to an array of longs, the allocation of
ret_stack_list went from allocating an array of 32 elements to just a
block defined by SHADOW_STACK_SIZE. Luckily, that's defined as PAGE_SIZE
and is much more than enough to hold 32 pointers. But it is way overkill
for the amount needed to allocate.
Change the allocation of ret_stack_list back to a kcalloc() of
FTRACE_RETSTACK_ALLOC_SIZE pointers.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241018215212.23f13f40@rorschach
Fixes: 42675b723b484 ("function_graph: Convert ret_stack to a series of longs")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The function graph infrastructure allocates a shadow stack for every task
when enabled. This includes the idle tasks. The first time the function
graph is invoked, the shadow stacks are created and never freed until the
task exits. This includes the idle tasks.
Only the idle tasks that were for online CPUs had their shadow stacks
created when function graph tracing started. If function graph tracing is
enabled and a CPU comes online, the idle task representing that CPU will
not have its shadow stack created, and all function graph tracing for that
idle task will be silently dropped.
Instead, use the CPU hotplug mechanism to allocate the idle shadow stacks.
This will include idle tasks for CPUs that come online during tracing.
This issue can be reproduced by:
# cd /sys/kernel/tracing
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo 0 > set_ftrace_pid
# echo function_graph > current_tracer
# echo 1 > options/funcgraph-proc
# echo 1 > /sys/devices/system/cpu/cpu1
# grep '<idle>' per_cpu/cpu1/trace | head
Before, nothing would show up.
After:
1) <idle>-0 | 0.811 us | __enqueue_entity();
1) <idle>-0 | 5.626 us | } /* enqueue_entity */
1) <idle>-0 | | dl_server_update_idle_time() {
1) <idle>-0 | | dl_scaled_delta_exec() {
1) <idle>-0 | 0.450 us | arch_scale_cpu_capacity();
1) <idle>-0 | 1.242 us | }
1) <idle>-0 | 1.908 us | }
1) <idle>-0 | | dl_server_start() {
1) <idle>-0 | | enqueue_dl_entity() {
1) <idle>-0 | | task_contending() {
Note, if tracing stops and restarts, the old way would then initialize
the onlined CPUs.
Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20241018214300.6df82178@rorschach
Fixes: 868baf07b1a25 ("ftrace: Fix memory leak with function graph and cpu hotplug")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
The cpu_emergency_register_virt_callback() function is used
unconditionally by the x86 kvm code, but it is declared (and defined)
conditionally:
#if IS_ENABLED(CONFIG_KVM_INTEL) || IS_ENABLED(CONFIG_KVM_AMD)
void cpu_emergency_register_virt_callback(cpu_emergency_virt_cb *callback);
...
leading to a build error when neither KVM_INTEL nor KVM_AMD support is
enabled:
arch/x86/kvm/x86.c: In function ‘kvm_arch_enable_virtualization’:
arch/x86/kvm/x86.c:12517:9: error: implicit declaration of function ‘cpu_emergency_register_virt_callback’ [-Wimplicit-function-declaration]
12517 | cpu_emergency_register_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/kvm/x86.c: In function ‘kvm_arch_disable_virtualization’:
arch/x86/kvm/x86.c:12522:9: error: implicit declaration of function ‘cpu_emergency_unregister_virt_callback’ [-Wimplicit-function-declaration]
12522 | cpu_emergency_unregister_virt_callback(kvm_x86_ops.emergency_disable_virtualization_cpu);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Fix the build by defining empty helper functions the same way the old
cpu_emergency_disable_virtualization() function was dealt with for the
same situation.
Maybe we could instead have made the call sites conditional, since the
callers (kvm_arch_{en,dis}able_virtualization()) have an empty weak
fallback. I'll leave that to the kvm people to argue about, this at
least gets the build going for that particular config.
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Kai Huang <kai.huang@intel.com>
Cc: Chao Gao <chao.gao@intel.com>
Cc: Farrah Chen <farrah.chen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull mailbox updates from Jassi Brar:
- fix kconfig dependencies (mhu-v3, omap2+)
- use devie name instead of genereic imx_mu_chan as interrupt name
(imx)
- enable sa8255p and qcs8300 ipc controllers (qcom)
- Fix timeout during suspend mode (bcm2835)
- convert to use use of_property_match_string (mailbox)
- enable mt8188 (mediatek)
- use devm_clk_get_enabled helpers (spreadtrum)
- fix device-id typo (rockchip)
* tag 'mailbox-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jassibrar/mailbox:
mailbox, remoteproc: omap2+: fix compile testing
dt-bindings: mailbox: qcom-ipcc: Document QCS8300 IPCC
dt-bindings: mailbox: qcom-ipcc: document the support for SA8255p
dt-bindings: mailbox: mtk,adsp-mbox: Add compatible for MT8188
mailbox: Use of_property_match_string() instead of open-coding
mailbox: bcm2835: Fix timeout during suspend mode
mailbox: sprd: Use devm_clk_get_enabled() helpers
mailbox: rockchip: fix a typo in module autoloading
mailbox: imx: use device name in interrupt name
mailbox: ARM_MHU_V3 should depend on ARM64
Pull i2c fixes from Wolfram Sang:
- fix DesignWare driver ENABLE-ABORT sequence, ensuring ABORT can
always be sent when needed
- check for PCLK in the SynQuacer controller as an optional clock,
allowing ACPI to directly provide the clock rate
- KEBA driver Kconfig dependency fix
- fix XIIC driver power suspend sequence
* tag 'i2c-for-6.12-rc1-additional_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: xiic: Fix pm_runtime_set_suspended() with runtime pm enabled
i2c: keba: I2C_KEBA should depend on KEBA_CP500
i2c: synquacer: Deal with optional PCLK correctly
i2c: designware: fix controller is holding SCL low while ENABLE bit is disabled
Selecting CONFIG_OMAP2PLUS_MBOX while compile testing
causes a build failure:
WARNING: unmet direct dependencies detected for OMAP2PLUS_MBOX
Depends on [n]: MAILBOX [=y] && (ARCH_OMAP2PLUS || ARCH_K3)
Selected by [m]:
- TI_K3_M4_REMOTEPROC [=m] && REMOTEPROC [=y] && (ARCH_K3 || COMPILE_TEST [=y])
Using 'select' to force-enable another subsystem is generally
a mistake and causes problems such as this one, so change the
three drivers that link against this driver to use 'depends on'
instead, and ensure the driver itself can be compile tested
regardless of the platform.
When compile-testing without CONFIG_TI_SCI_PROTOCOL=m, there
is a chance for a link failure, so add a careful dependency
on that.
arm-linux-gnueabi-ld: drivers/remoteproc/ti_k3_m4_remoteproc.o: in function `k3_m4_rproc_probe':
ti_k3_m4_remoteproc.c:(.text.k3_m4_rproc_probe+0x76): undefined reference to `devm_ti_sci_get_by_phandle'
Fixes: ebcf9008a895 ("remoteproc: k3-m4: Add a remoteproc driver for M4F subsystem")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Andrew Davis <afd@ti.com>
Reviewed-by: Martyn Welch <martyn.welch@collabora.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Pull dma-mapping fix from Christoph Hellwig:
- handle chained SGLs in the new tracing code (Christoph Hellwig)
* tag 'dma-mapping-6.12-2024-09-29' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix DMA API tracing for chained scatterlists
I2C host fixes for v6.12-rc1
The DesignWare driver now has the correct ENABLE-ABORT sequence,
ensuring ABORT can always be sent when needed.
In the SynQuacer controller we now check for PCLK as an optional
clock, allowing ACPI to directly provide the clock rate.
The recent KEBA driver required a dependency fix in Kconfig.
The XIIC driver now has a corrected power suspend sequence.
Document the Inter-Processor Communication Controller on the Qualcomm
QCS8300 Platform, which will be used to route interrupts across various
subsystems found on the SoC.
Signed-off-by: Jingyi Wang <quic_jingyw@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Pull more SCSI updates from James Bottomley:
"These are mostly minor updates.
There are two drivers (lpfc and mpi3mr) which missed the initial
pull and a core change to retry a start/stop unit which affect
suspend/resume"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (32 commits)
scsi: lpfc: Update lpfc version to 14.4.0.5
scsi: lpfc: Support loopback tests with VMID enabled
scsi: lpfc: Revise TRACE_EVENT log flag severities from KERN_ERR to KERN_WARNING
scsi: lpfc: Ensure DA_ID handling completion before deleting an NPIV instance
scsi: lpfc: Fix kref imbalance on fabric ndlps from dev_loss_tmo handler
scsi: lpfc: Restrict support for 32 byte CDBs to specific HBAs
scsi: lpfc: Update phba link state conditional before sending CMF_SYNC_WQE
scsi: lpfc: Add ELS_RSP cmd to the list of WQEs to flush in lpfc_els_flush_cmd()
scsi: mpi3mr: Update driver version to 8.12.0.0.50
scsi: mpi3mr: Improve wait logic while controller transitions to READY state
scsi: mpi3mr: Update MPI Headers to revision 34
scsi: mpi3mr: Use firmware-provided timestamp update interval
scsi: mpi3mr: Enhance the Enable Controller retry logic
scsi: sd: Fix off-by-one error in sd_read_block_characteristics()
scsi: pm8001: Do not overwrite PCI queue mapping
scsi: scsi_debug: Remove a useless memset()
scsi: pmcraid: Convert comma to semicolon
scsi: sd: Retry START STOP UNIT commands
scsi: mpi3mr: A performance fix
scsi: ufs: qcom: Update MODE_MAX cfg_bw value
...
scatterlist allocations can be chained, and thus all iterations need to
use the chain-aware iterators. Switch the newly added tracing to use the
proper iterators so that they work with chained scatterlists.
Fixes: 038eb433dc14 ("dma-mapping: add tracing for dma-mapping API calls")
Reported-by: syzbot+95e4ef83a3024384ec7a@syzkaller.appspotmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sean Anderson <sean.anderson@linux.dev>
Tested-by: syzbot+95e4ef83a3024384ec7a@syzkaller.appspotmail.com
Pull SoC update from Arnd Bergmann:
"Convert ep93xx to devicetree
This concludes a long journey towards replacing the old board files
with devictree description on the Cirrus Logic EP93xx platform.
Nikita Shubin has been working on this for a long time, for details
see the last post on
https://lore.kernel.org/lkml/20240909-ep93xx-v12-0-e86ab2423d4b@maquefel.me/"
* tag 'soc-ep93xx-dt-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (47 commits)
dt-bindings: gpio: ep9301: Add missing "#interrupt-cells" to examples
MAINTAINERS: Update EP93XX ARM ARCHITECTURE maintainer
soc: ep93xx: drop reference to removed EP93XX_SOC_COMMON config
net: cirrus: use u8 for addr to calm down sparse
dmaengine: cirrus: use snprintf() to calm down gcc 13.3.0
dmaengine: ep93xx: Fix a NULL vs IS_ERR() check in probe()
pinctrl: ep93xx: Fix raster pins typo
spi: ep93xx: update kerneldoc comments for ep93xx_spi
clk: ep93xx: Fix off by one in ep93xx_div_recalc_rate()
clk: ep93xx: add module license
dmaengine: cirrus: remove platform code
ASoC: cirrus: edb93xx: Delete driver
ARM: ep93xx: soc: drop defines
ARM: ep93xx: delete all boardfiles
ata: pata_ep93xx: remove legacy pinctrl use
pwm: ep93xx: drop legacy pinctrl
ARM: ep93xx: DT for the Cirrus ep93xx SoC platforms
ARM: dts: ep93xx: Add EDB9302 DT
ARM: dts: ep93xx: add ts7250 board
ARM: dts: add Cirrus EP93XX SoC .dtsi
...
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