04438a06c4
So far the setup of BDL table is performed at the prepare stage, where all PCM parameters have been already set up. When something wrong happens at it, we return -EINVAL; it's supposed to be a rare case since the involved memory allocation is a small chunk of kmalloc for the table. However, when we receive too many small non-contiguous pages in highly fragmented memories, it may overflow the max table size, resulting in the same -EINVAL error from the prepare, too. A bad scenario is that user-space cannot know what went wrong (as it's an error from the prepare stage) and -EINVAL, hence it may retry with the same parameters, failing again repeatedly. In this patch, we try to set up the BDL table at hw_params right after the buffer allocation, and return -ENOMEM if it overflows. This allows user-space knowing that it should reduce the buffer size request accordingly and may retry with more fitting parameters. Link: https://lore.kernel.org/r/20240221100607.6565-1-tiwai@suse.de Signed-off-by: Takashi Iwai <tiwai@suse.de>
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.