ac91e69805
Sheng Bi reports that pci_bridge_secondary_bus_reset() may fail to wait for devices on the secondary bus to become accessible after reset: Although it does call pci_dev_wait(), it erroneously passes the bridge's pci_dev rather than that of a child. The bridge of course is always accessible while its secondary bus is reset, so pci_dev_wait() returns immediately. Sheng Bi proposes introducing a new pci_bridge_secondary_bus_wait() function which is called from pci_bridge_secondary_bus_reset(): https://lore.kernel.org/linux-pci/20220523171517.32407-1-windy.bi.enflame@gmail.com/ However we already have pci_bridge_wait_for_secondary_bus() which does almost exactly what we need. So far it's only called on resume from D3cold (which implies a Fundamental Reset per PCIe r6.0 sec 5.8). Re-using it for Secondary Bus Resets is a leaner and more rational approach than introducing a new function. That only requires a few minor tweaks: - Amend pci_bridge_wait_for_secondary_bus() to await accessibility of the first device on the secondary bus by calling pci_dev_wait() after performing the prescribed delays. pci_dev_wait() needs two parameters, a reset reason and a timeout, which callers must now pass to pci_bridge_wait_for_secondary_bus(). The timeout is 1 sec for resume (PCIe r6.0 sec 6.6.1) and 60 sec for reset (commit |
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.