From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- 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