Re: [PATCH] shmem missing cache flush

Manfred Spraul (manfred@colorfullife.com)
Mon, 28 Oct 2002 17:50:41 +0100

Is it permitted to call flush_dcache_page() on pages that are not in the
page cache?
The documentation is ambiguous, it only mentions how archs can handle
dcache aliases for page cache users.

What about the user space accesses that kmap user space pages directly,
without copy_*_user?

For example:
- ptrace
- disk transfers that end up calling __bio_kmap() - RAID-5, ide error
handling.
Could be from irq context!
- hole handling for O_DIRECT file access.

In all 3 cases, the target could be outside of the page cache.

--
    Manfred


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/