Messages in this thread | | | Date | Sun, 31 Dec 2006 01:46:30 -0800 (PST) | Subject | Re: fuse, get_user_pages, flush_anon_page, aliasing caches and all that again | From | David Miller <> |
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From: Russell King <rmk+lkml@arm.linux.org.uk> Date: Sun, 31 Dec 2006 09:23:18 +0000
> We do this on ARM - if page_mapping() is NULL, we flush the kernel > alias unconditionally. However, we have no view where the user > mapping of that page is, which is where the problem is. Cache lines > remain allocated for the user mapping and data contained within is > not visible via the kernel mapping.
You can walk the RMAP list.
> However, it's not only FUSE which is suffering - direct-IO also doesn't > work. If my analysis is correct, only _two_ users of get_user_pages() > with the current process actually does the right thing and that's ptrace > and ELF core dumping. All other users are buggy.
I do not argue that these cases need work, in fact I am aware of the direct-IO bit. - 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/
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