On 06/12/2018 12:13, Greg KH wrote: > 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? https://lore.kernel.org/lkml/20181130202328.65359-2-kirill.shutemov@xxxxxxxxxxxxxxx/ Still pending upstream. Just pinged tglx. Juergen
