Messages in this thread | | | From | nathan.zook@amd ... | Subject | RE: HIGH MEMORY access | Date | Fri, 3 Mar 2000 09:50:03 -0600 |
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This is changing. The new patches will be reclaim-enabled, so those pages will be mapped, and the max_pfn-class variables will reflect their presence.
Nathan
> -----Original Message----- > From: Manfred Spraul [mailto:manfreds@colorfullife.com] > Sent: Friday, March 03, 2000 8:32 AM > To: Ingo Molnar > Cc: Lyle Coder; sct@redhat.com; linux-kernel@vger.rutgers.edu > Subject: Re: HIGH MEMORY access > > > Ingo Molnar wrote: > > > > On Fri, 3 Mar 2000, Manfred Spraul wrote: > > > > > Now I'm confused: I thought that ioremap() should be used > for reserved > > > memory, and kmap() for normal memory (e820: ram) with > > > page->virtual==NULL. > > > > well you can use kmap() for anything, not just high memory. > > kmap() assumes that a "struct page" exists. > > It's not guaranteed that a "struct page" exists for reserved memory: > this could happen if you boot with "mem=32M", or if the ACPI > tables are > the last element in the e820 map: > > * max_pfn is set to the end if the last usable block. > * then the ACPI tables follow --> they are behind max_pfn --> > behind the > end of mem_map. > > Not everyone has 8 GB memory :-( > > -- > Manfred > > - > To unsubscribe from this list: send the line "unsubscribe > linux-kernel" in > the body of a message to majordomo@vger.rutgers.edu > Please read the FAQ at http://www.tux.org/lkml/ >
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
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