Messages in this thread | | | Date | Mon, 9 Jan 2017 13:00:33 +0000 | From | Matt Fleming <> | Subject | Re: [PATCH v3 2/2] efi: efi_mem_reserve(): don't reserve through memblock after mm_init() |
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On Fri, 06 Jan, at 07:28:40PM, Ard Biesheuvel wrote: > > This is my point exactly. But it appears efi_free_boot_services() > occurs much later than I thought, and so there is a sizabe time window > where SLAB is up but reservations can still be made. But we don't > check whether efi_free_boot_services() has been called.
True. This has only been correct thus far because all code has been audited, but adding a check to catch future offenders is a good idea.
> Another problem is that we never check that the reservation is > covered by a BootServicesData region, which are the only ones that > are guaranteed to be retained up to this point.
The runtime regions are guaranteed to be retained too.
Again, this shouldn't actually be a problem today, but the potential for breakage here warrants some kind of check and loud warning.
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