Okay, I went back through the kernel PPAs and in fact the most recent one that I can get to boot under 32-bit PV mode Xen is 4.13.16. 4.14-rc1 does not boot.
I realised then that it was possible that I had never tested any version of 32-bit Ubuntu 18.04 under Xen. It is possible that I only ever tested it 64-bit. The only reason why I am looking into this now is because a user with a 32-bit Ubuntu 16.04 did a release upgrade to 18.04. On seeing that a large number of upstream kernel releases don't boot under 32-bit Xen, I did a quick check what the situation is in Debian. I know that I tested the current Debian stable both 32- and 64-bit. But that is based on kernel 4.9.x. A 4.17.x kernel is available in stretch-backports, so I tried that, and sure enough that crashes too. So, I'm a little shocked that I would be the first to notice this, but it seems like the upstream Linux kernel stopped working under 32-bit PV mode Xen quite some time ago. I am more familiar with Debian so I am going to built the latest upstream stable kernel release on Debian and check that it also crashes in the same way, and if so then I guess I report it upstream, maybe do a bisection myself in Debian. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1789118 Title: Fails to boot under Xen PV: BUG: unable to handle kernel paging request at edc21fd9 Status in linux package in Ubuntu: Triaged Status in linux source package in Bionic: Triaged Bug description: After the most recent 18.04 32-bit upgrade of linux-image-generic, it now refuses to boot under Xen PV mode: . . . [ 0.114370] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns [ 0.114382] futex hash table entries: 256 (order: 2, 16384 bytes) [ 0.114423] pinctrl core: initialized pinctrl subsystem [ 0.134326] RTC time: 165:165:165, date: 165/165/65 [ 0.134442] NET: Registered protocol family 16 [ 0.134457] xen:grant_table: Grant tables using version 1 layout [ 0.134502] Grant table initialized [ 0.134544] audit: initializing netlink subsys (disabled) [ 0.134611] audit: type=2000 audit(1535307799.132:1): state=initialized audit_enabled=0 res=1 [ 0.134678] EISA bus registered [ 0.136019] PCI: setting up Xen PCI frontend stub [ 0.136073] BUG: unable to handle kernel paging request at edc21fd9 [ 0.136084] IP: eisa_bus_probe+0x19/0x36 [ 0.136089] *pdpt = 0000000001ee6027 *pde = 0000000029cc6067 *pte = 0000000000000000 [ 0.136100] Oops: 0000 [#1] SMP [ 0.136105] Modules linked in: [ 0.136111] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.15.0-33-generic #36-Ubuntu [ 0.136120] EIP: eisa_bus_probe+0x19/0x36 [ 0.136125] EFLAGS: 00010246 CPU: 0 [ 0.136130] EAX: edc21fd9 EBX: 00000000 ECX: 01e0d000 EDX: 00000200 [ 0.136138] ESI: c1d0d452 EDI: c1dd34a4 EBP: e9c89f24 ESP: e9c89f24 [ 0.136145] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: e021 [ 0.136154] CR0: 80050033 CR2: edc21fd9 CR3: 01e10000 CR4: 00042660 [ 0.136166] Call Trace: [ 0.136173] do_one_initcall+0x49/0x174 [ 0.136179] ? parse_args+0x143/0x390 [ 0.136187] ? set_debug_rodata+0x14/0x14 [ 0.136193] kernel_init_freeable+0x149/0x1c5 [ 0.136201] ? rest_init+0xa0/0xa0 [ 0.136207] kernel_init+0xd/0xf0 [ 0.136213] ret_from_fork+0x2e/0x38 [ 0.140000] Code: ff b8 df 43 ae c1 e8 35 1b 88 ff e8 20 12 88 ff c9 c3 3e 8d 74 26 00 55 b9 04 00 00 00 31 d2 b8 d9 ff 0f 00 89 e5 e8 35 8d 35 ff <8b> 10 81 fa 45 49 53 41 75 0a c7 05 a0 76 ed c1 01 00 00 00 e8 [ 0.140000] EIP: eisa_bus_probe+0x19/0x36 SS:ESP: e021:e9c89f24 [ 0.140000] CR2: 00000000edc21fd9 [ 0.140000] ---[ end trace 8c00b3cb7d4f06ba ]--- [ 0.140013] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 This is: [ 0.000000] Linux version 4.15.0-33-generic (buildd@lgw01-amd64-038) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #36-Ubuntu SMP Wed Aug 15 13:44:35 UTC 2018 (Ubuntu 4.15.0-33.36-generic 4.15.18) Switching to a 64-bit kernel allows boot to proceed. I cannot include output of the commands you request (uname, version_signature, dmesg, lspci) because the guest doesn't boot. The above kernel output is from a just-installed clean guest however. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1789118/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
