Messages in this thread | | | Date | Tue, 23 Apr 2019 18:49:24 +0800 | From | Dave Young <> | Subject | Re: [PATCH] x86/kexec: always ensure EFI systab region is mapped |
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On 04/23/19 at 06:20am, Junichi Nomura wrote: > On 4/22/19 6:28 PM, Kairui Song wrote: > > The reason is the systab region is not mapped by the identity mapping > > provided by kexec. Currently kexec only create identity mapping for > > mem regions, wihch won't cover the systab. So second kernel will be > > accessing a not mapped memory region and cause fault. > > But as kexec tend to pad the map region up to PUD size, the > > systab could be included in the map by accident, so it worked on > > some machines, but that will be broken easily and unstable. > > Is the mapping of ACPI tables just by luck, too?
Hmm, guess it should be mapped by luck, here is the range on the T420: da99f000 - dae9efff Reserved (efi systab fall in this region) daf9f000 - daffefff ACPI tables
Thanks Dave
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