Re: 4.17.x won't boot due to "x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G"

[Thomas Gleixner]

On Tue, 3 Jul 2018, Kirill A. Shutemov wrote:
> On Tue, Jul 03, 2018 at 01:24:49PM +0200, Gabriel C wrote:
> > 2018-07-01 23:32 GMT+02:00 Benjamin Gilbert <bgilbert@xxxxxxxxxx>:
> > > On Sun, Jul 01, 2018 at 05:15:59PM -0400, Benjamin Gilbert wrote:
> > >> 4.17 kernels built with the CoreOS Container Linux toolchain and kconfig,
> > >> up to and including 4.17.3, fail to boot on AMD64 running in (at least)
> > >> QEMU/KVM.  No messages are shown post-GRUB; the VM instantly reboots.
> > >> Reverting commit 194a9749c73d ("x86/boot/compressed/64: Handle 5-level
> > >> paging boot if kernel is above 4G") fixes it.  I've attached our kernel
> > >> config for reference, and am happy to test patches, provide sample QCOW
> > >> images, etc.
> > >
> > 
> > Also see https://bugzilla.kernel.org/show_bug.cgi?id=200385 ,
> > 
> > 0a1756bd2897951c03c1cb671bdfd40729ac2177 is acting up
> > too with the same symptoms
> 
> I tracked it down to -flto in LDFLAGS. I'll look more into this.

And what sets -flto in LDFLAGS? I can't find anything in the kernel
build/Makefiles.

Thanks,

	tglx