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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, May 28, 2019 at 07:11:22PM +0200, Ard Biesheuvel wrote: > On Tue, 28 May 2019 at 19:07, Ard Biesheuvel wrote: > > > > On Tue, 28 May 2019 at 18:10, Steve Capper wrote: > > > > > > In order to prepare for a variable VA_BITS we need to account for a > > > variable size VMEMMAP which in turn means the position of the fixed map > > > is variable at compile time. > > > > > > Thus, we need to replace the BUILD_BUG_ON's that check the fixed map > > > position with BUG_ON's. > > > > > > Signed-off-by: Steve Capper > > > > Do we still need this patch now that VMEMMAP_SIZE is a compile time > > constant again? Or am I missing something? > > > > Never mind. You are moving the start of the linear region and the > start of the vmemmap region. > > I wonder if this is really necessry, though. On a 48-bit VA only > system, the linear region could still start at 0xfff0_.... as long as > we don't put any physical memory there (and we already move around our > physical memory inside the linear region when KASLR is enabled) > > Thanks Ard, This patch is actually superfluous, it was needed in earlier versions of the series; but VMEMMAP is fixed at compile time. I have removed this patch from the series. I will also see if I can simplify the de-constifying patches and bitmask replacement logic. Cheers, -- Steve _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel