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ec6ce7075e
The OS descriptors logic had the high/low byte of w_value inverted, causing
the extended properties to not be accessible for interface != 0.
>From the Microsoft documentation:
https://learn.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-os-1-0-descriptors-specification
OS_Desc_CompatID.doc (w_index = 0x4):
- wValue:
High Byte = InterfaceNumber. InterfaceNumber is set to the number of the
interface or function that is associated with the descriptor, typically
0x00. Because a device can have only one extended compat ID descriptor,
it should ignore InterfaceNumber, regardless of the value, and simply
return the descriptor.
Low Byte = 0. PageNumber is used to retrieve descriptors that are larger
than 64 KB. The header section is 16 bytes, so PageNumber is set to 0 for
this request.
We currently do not support >64KB compat ID descriptors, so verify that the
low byte is 0.
OS_Desc_Ext_Prop.doc (w_index = 0x5):
- wValue:
High byte = InterfaceNumber. The high byte of wValue is set to the number
of the interface or function that is associated with the descriptor.
Low byte = PageNumber. The low byte of wValue is used to retrieve
descriptors that are larger than 64 KB. The header section is 10 bytes, so
PageNumber is set to 0 for this request.
We also don't support >64KB extended properties, so verify that the low byte
is 0 and use the high byte for the interface number.
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| 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 reStructuredText 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.