On Thu, Nov 29, 2018 at 02:35:17PM +0100, Juergen Gross wrote: > On 29/11/2018 14:26, Kirill A. Shutemov wrote: > > On Thu, Nov 29, 2018 at 09:41:25AM +0000, Juergen Gross wrote: > >> On 29/11/2018 02:22, Hans van Kranenburg wrote: > >>> Hi, > >>> > >>> As also seen at: > >>> https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914951 > >>> > >>> Attached there are two serial console output logs. One is starting with > >>> Xen 4.11 (from debian unstable) as dom0, and the other one without Xen. > >>> > >>> [ 2.085543] BUG: unable to handle kernel paging request at > >>> ffff888d9fffc000 > >>> [ 2.085610] PGD 200c067 P4D 200c067 PUD 0 > >>> [ 2.085674] Oops: 0000 [#1] SMP NOPTI > >>> [ 2.085736] CPU: 1 PID: 1 Comm: swapper/0 Not tainted > >>> 4.19.0-trunk-amd64 #1 Debian 4.19.5-1~exp1+pvh1 > >>> [ 2.085823] Hardware name: HP ProLiant DL360 G7, BIOS P68 05/21/2018 > >>> [ 2.085895] RIP: e030:ptdump_walk_pgd_level_core+0x1fd/0x490 > >>> [...] > >> > >> The offending stable commit is 4074ca7d8a1832921c865d250bbd08f3441b3657 > >> ("x86/mm: Move LDT remap out of KASLR region on 5-level paging"), this > >> is commit d52888aa2753e3063a9d3a0c9f72f94aa9809c15 upstream. > >> > >> Current upstream kernel is booting fine under Xen, so in general the > >> patch should be fine. Using an upstream kernel built from above commit > >> (with the then needed Xen fixup patch 1457d8cf7664f34c4ba534) is fine, > >> too. > >> > >> Kirill, are you aware of any prerequisite patch from 4.20 which could be > >> missing in 4.19.5? > > > > I'm not. > > > > Let me look into this. > > > > What is making me suspicious is the failure happening just after > releasing the init memory. Maybe there is an access to .init.data > segment or similar? The native kernel booting could be related to the > usage of 2M mappings not being available in a PV-domain. Did this ever get fixed anywhere that I can properly backport it to the 4.19.y tree? thanks, greg k-h
