Bug 228966 - Interface for non-cached memory with userland control
Summary: Interface for non-cached memory with userland control
Status: New
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: Any Any
: --- Affects Many People
Assignee: Rodney W. Grimes
URL:
Keywords:
Depends on:
Blocks: 228911
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Reported: 2018-06-12 16:57 UTC by Rodney W. Grimes
Modified: 2018-08-02 01:55 UTC (History)
4 users (show)

See Also:


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Description Rodney W. Grimes freebsd_committer 2018-06-12 16:57:18 UTC
Interface for non-cached memory with userland control
Comment 1 Rodney W. Grimes freebsd_committer 2018-06-12 16:58:59 UTC
Point was "not jhb" so take until we can find someone to run point on this, and put jhb in the cc: list to help finding a point person
Comment 2 Conrad Meyer freebsd_committer 2018-06-12 17:55:07 UTC
Can we clarify what this means and what the goal is?

What's the envisioned use case?  Graphics drivers, something else?

What requirements should the interface have?
Comment 3 Conrad Meyer freebsd_committer 2018-08-02 01:52:46 UTC
Related to r337053 and https://reviews.freebsd.org/D15583 ?  Current logic only allows UNCACHED mappings but perhaps the goal of this PR is an interface to change cacheability of mappings.
Comment 4 Conrad Meyer freebsd_committer 2018-08-02 01:55:47 UTC
Whoops.  Kernel interface supports any valid mapping type.  pciconf -D only does UC, which is probably ok for that tool.  Can this be resolved or did we have anything else in mind?