From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- Documentation/driver-api/xilinx/eemi.rst | 40 +++++++++++++++++++++++++++++++ Documentation/driver-api/xilinx/index.rst | 9 +++++++ 2 files changed, 49 insertions(+) create mode 100644 Documentation/driver-api/xilinx/eemi.rst create mode 100644 Documentation/driver-api/xilinx/index.rst (limited to 'Documentation/driver-api/xilinx') diff --git a/Documentation/driver-api/xilinx/eemi.rst b/Documentation/driver-api/xilinx/eemi.rst new file mode 100644 index 000000000..c1bc47b90 --- /dev/null +++ b/Documentation/driver-api/xilinx/eemi.rst @@ -0,0 +1,40 @@ +==================================== +Xilinx Zynq MPSoC EEMI Documentation +==================================== + +Xilinx Zynq MPSoC Firmware Interface +------------------------------------- +The zynqmp-firmware node describes the interface to platform firmware. +ZynqMP has an interface to communicate with secure firmware. Firmware +driver provides an interface to firmware APIs. Interface APIs can be +used by any driver to communicate with PMC(Platform Management Controller). + +Embedded Energy Management Interface (EEMI) +---------------------------------------------- +The embedded energy management interface is used to allow software +components running across different processing clusters on a chip or +device to communicate with a power management controller (PMC) on a +device to issue or respond to power management requests. + +Any driver who wants to communicate with PMC using EEMI APIs use the +functions provided for each function. + +IOCTL +------ +IOCTL API is for device control and configuration. It is not a system +IOCTL but it is an EEMI API. This API can be used by master to control +any device specific configuration. IOCTL definitions can be platform +specific. This API also manage shared device configuration. + +The following IOCTL IDs are valid for device control: +- IOCTL_SET_PLL_FRAC_MODE 8 +- IOCTL_GET_PLL_FRAC_MODE 9 +- IOCTL_SET_PLL_FRAC_DATA 10 +- IOCTL_GET_PLL_FRAC_DATA 11 + +Refer EEMI API guide [0] for IOCTL specific parameters and other EEMI APIs. + +References +---------- +[0] Embedded Energy Management Interface (EEMI) API guide: + https://www.xilinx.com/support/documentation/user_guides/ug1200-eemi-api.pdf diff --git a/Documentation/driver-api/xilinx/index.rst b/Documentation/driver-api/xilinx/index.rst new file mode 100644 index 000000000..c95bda55d --- /dev/null +++ b/Documentation/driver-api/xilinx/index.rst @@ -0,0 +1,9 @@ + +=========== +Xilinx FPGA +=========== + +.. toctree:: + :maxdepth: 1 + + eemi -- cgit v1.3.1