On 02/24/19 at 09:25pm, Pingfan Liu wrote: > On Fri, Feb 22, 2019 at 9:00 PM Borislav Petkov <bp@xxxxxxxxx> wrote: > > > > On Fri, Feb 22, 2019 at 09:42:41AM +0100, Joerg Roedel wrote: > > > The current default of 256MB was found by experiments on a bigger > > > number of machines, to create a reasonable default that is at least > > > likely to be sufficient of an average machine. > > > > Exactly, and this is what makes sense. > > > > The code should try the requested reservation and if it fails, it should > > try high allocation with default swiotlb size because we need to reserve > > *some* range. > > > > If that reservation succeeds, we should say something along the lines of > > > > "... requested range failed, reserved <X> range instead." > > > Maybe I misunderstood you, but does "requested range failed" mean that > user specify the range? If yes, then it should be the duty of user as > you said later, not the duty of kernel" If you go with the changes in your current patch it is needed to say something like: "crashkernel: can not find free memory under 4G, reserve XM@.. instead" Also need to print the reserved low memory area in case ,high being used. But for 896M -> 4G, the 896M faulure is not necessary to show in dmesg, it is some in kernel logic. Thanks Dave _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec
