Messages in this thread | | | Date | Sat, 19 Jan 2008 19:45:43 +0100 | From | Ingo Molnar <> | Subject | Re: ACPI early ioremap problems |
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* Andi Kleen <andi@firstfloor.org> wrote:
> On Sat, Jan 19, 2008 at 04:30:55PM +0100, Ingo Molnar wrote: > > > > that case it's a 64-bit early_ioremap() bug that we want to find > > > > even if ACPI didnt use early_ioremap(). > > > > > > > > and this all runs before zap_low_mappings(), right? > > > > > > No after. Since some time x86-64 does the equivalent of z_l_m() in > > > head64(); this means before start_kernel and definitely before > > > setup_arch which sets up ACPI. > > > > that would mean early_ioremap() should switch to ioremap() after that > > point. Could you try that, does it resolve the failure you are seeing? > > ioremap() does alloc_page and that won't work before paging_init(). > Early ACPI scan is before paging_init() because paging_init() needs > node discovery at at least; which requires some ACPI tables.
hm, so are you saying that on 64-bit there's in essence no usable ioremap facility between zap_low_mappings() and paging_init()? (early_ioremap() is not usable anymore, and ioremap() is not yet usable.) I guess we'll have to pick up the 32-bit early_ioremap() code for 64-bit as well.
Ingo
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