Hi Anshuman, On Wed, Nov 11, 2020 at 09:18:56AM +0530, Anshuman Khandual wrote: > On 11/11/20 12:44 AM, Catalin Marinas wrote: > > On Wed, 14 Oct 2020 10:18:57 +0200, Ard Biesheuvel wrote: > >> As a hardening measure, we currently randomize the placement of > >> physical memory inside the linear region when KASLR is in effect. > >> Since the random offset at which to place the available physical > >> memory inside the linear region is chosen early at boot, it is > >> based on the memblock description of memory, which does not cover > >> hotplug memory. The consequence of this is that the randomization > >> offset may be chosen such that any hotplugged memory located above > >> memblock_end_of_DRAM() that appears later is pushed off the end of > >> the linear region, where it cannot be accessed. > >> > >> [...] > > > > Applied to arm64 (for-next/mem-hotplug), thanks! > > > > [1/1] arm64: mm: account for hotplug memory when randomizing the linear > > region > > https://git.kernel.org/arm64/c/97d6786e0669 > > Got delayed and never made here in time, sorry about that. Nonetheless, > I have got something working with respect to the generic mechanism that > David Hildenbrand had asked for earlier. > > https://patchwork.kernel.org/project/linux-arm-kernel/patch/1600332402-30123-1-git-send-email-anshuman.khand...@arm.com/
There was a lot of discussion around this patch but I haven't seen any new version posted. > I am wondering if we could instead consider merging the above patch with > a small change that Ard had pointed out earlier [1], I will send out a > revision if required. If your patch fixes the randomisation issue that Ard addressed, I'm happy to replace that with your patch. But please post a new version and get some acks in place from the parties involved in the discussion. Thanks. -- Catalin
