Messages in this thread | | | Date | Tue, 28 Oct 2014 20:14:02 -0700 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH] mm: Avoid overlap the fixmap area on i386 |
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On 10/28/2014 10:29 AM, Thomas Gleixner wrote: > On Tue, 28 Oct 2014, H. Peter Anvin wrote: >> On 10/28/2014 04:06 AM, Thomas Gleixner wrote: >>>> >>>> The available address we can use is lower than FIXADDR_BOOT_START. So >>>> We will set the kmap boundary below the FIXADDR_BOOT_START, if configure >>>> the high memory. >>>> >>>> If we configure the high memory, the vmalloc reserve area should end >>>> up to PKMAP_BASE, otherwise should end up to FIXADDR_BOOT_START. >>> >>> Which is not really a problem, because the FIXADDR_BOOT area is only >>> used during boot for early_ioremap() and it's unused when ioremap() is >>> functional. vmalloc becomes available after early boot so the >>> FIXADDR_BOOT area is available for reuse. >>> >> >> Given the very limited address space available on i386, it would be >> extremely undesirable to not reuse address space when possible. > > Fair enough. Then we should do that for the highmem=y case as well. >
It is probably even more important for highmem=y...
-hpa
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