2.1 KiB
Vendor Reset
The goal of this project is to provide a kernel module that is capable of resetting hardware devices into a state where they can be re-initialized or passed through into a virtual machine (VFIO). While it would be great to have these in the kernel as PCI quirks, some of the reset procedures are very complex and would never be accepted as a quirk (ie AMD Vega 10).
By providing this as an out of tree kernel module, vendors will be able to easily create pull requests to add functionality to this module, and users will be able to easily update this module without requiring a complete kernel rebuild.
Patching the kernel
TL;DR - No patching required.
This module has been written to use ftrace to hook pci_dev_specific_reset,
allowing it to handle device resets directly without patching the running
kernel. Simply modprobing the module is enough to enable the reset routines for
all supported hardware.
Requirements
Ensure your kernel has the following options enabled:
CONFIG_FTRACE=y
CONFIG_KPROBES=y
CONFIG_PCI_QUIRKS=y
CONFIG_KALLSYMS=y
CONFIG_KALLSYMS_ALL=y
CONFIG_FUNCTION_TRACER=y
Installing
This module can be installed either using the standard make, make install
pattern, or through dkms (recommended).
dkms install .
Usage
Either modprobe vendor-reset or add the device to the appropriate place to
load it at system boot, such as /etc/modules (Debian). Consult your
distribution's documentation as to the best way to perform this.
Supported Devices
| Vendor | Family | Common Name(s) |
|---|---|---|
| AMD | Polaris 10 | |
| AMD | Polaris 11 | |
| AMD | Polaris 12 | |
| AMD | Vega 10 | Vega 56/64 |
| AMD | Vega 20 | Radeon VII |
| AMD | Navi 10 | 5600XT, 5700, 5700XT |
| AMD | Navi 12 | Pro 5600M |
| AMD | Navi 14 | Pro 5300, RX 5300, 5500XT |
Developing
If you are a vendor intending to add support for your device to this project please first consider two things:
- Can you fix your hardware/firmware to reset correctly using FLR or a BUS reset?
- Is the reset simple enough that it should really be a kernel pci quirk (see: kernel/drivers/pci/quirk.c)?
If you answer yes to either of these questions this project is not for you.