On Fri, 4 Dec 2020 at 18:44, Jon Hunter <jonathanh@xxxxxxxxxx> wrote: > > > On 04/12/2020 16:07, Marek Szyprowski wrote: > > Hi All, > > > > On 04.12.2020 14:42, Qian Cai wrote: > >> On Thu, 2020-12-03 at 23:23 +0800, carver4lio@xxxxxxx wrote: > >>> From: Hailong Liu <liu.hailong6@xxxxxxxxxx> > >>> > >>> When system in the booting stage, pages span from [start, end] of a memblock > >>> are freed to buddy in a order as large as possible (less than MAX_ORDER) at > >>> first, then decrease gradually to a proper order(less than end) in a loop. > >>> > >>> However, *min(MAX_ORDER - 1UL, __ffs(start))* can not get the largest order > >>> in some cases. > >>> Instead, *__ffs(end - start)* may be more appropriate and meaningful. > >>> > >>> Signed-off-by: Hailong Liu <liu.hailong6@xxxxxxxxxx> > >> Reverting this commit on the top of today's linux-next fixed boot crashes on > >> multiple NUMA systems. > > > > I confirm. Reverting commit 4df001639c84 ("mm/memblock: use a more > > appropriate order calculation when free memblock pages") on top of linux > > next-20201204 fixed booting of my ARM32bit test systems. > > > FWIW, I also confirm that this is causing several 32-bit Tegra platforms > to crash on boot and reverting this fixes the problem. I had the same experience on an arm64 system. Cheers, Anders