On 02/20/19 at 09:32am, Borislav Petkov wrote: > On Mon, Feb 18, 2019 at 09:48:20AM +0800, Dave Young wrote: > > It is ideal if kernel can do it automatically, but I'm not sure if > > kernel can predict the swiotlb reserved size automatically. > > Do you see how even more absurd this gets? > > If the kernel cannot know the swiotlb reserved size automatically, how > is the normal user even supposed to know?! > > I see swiotlb_size_or_default() so we have a sane default which we fall > back to. Now where's the problem with that? Good question, I expect some answer from people who know more about the background. It would be good to have some actual test results, Pingfan is trying to do some tests. Previously Joerg posted below patch, maybe he has some idea. Joerg? commit 94fb9334182284e8e7e4bcb9125c25dc33af19d4 Author: Joerg Roedel <jroedel@xxxxxxx> Date: Wed Jun 10 17:49:42 2015 +0200 x86/crash: Allocate enough low memory when crashkernel=high Thanks Dave _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec