On Sun, Dec 01, 2019 at 04:10:11PM +0100, Borislav Petkov wrote: > So lemme first confirm it really is caused by those patches. Yeah, those patches are causing it. Tried your current master - it is OK - and then applied Andrew's patches I was CCed on, ontop, and I got in a VM: VFS: Mounted root (ext4 filesystem) readonly on device 8:2. devtmpfs: mounted Freeing unused kernel image (initmem) memory: 664K Write protecting kernel text and read-only data: 18164k NX-protecting the kernel data: 7416k BUG: kernel NULL pointer dereference, address: 00000014 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page *pdpt = 0000000000000000 *pde = f000ff53f000ff53 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.4.0+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.1-1 04/01/2014 EIP: __lock_acquire.isra.0+0x2e8/0x4e0 Code: e8 bd a1 2f 00 85 c0 74 11 8b 1d 08 8f 26 c5 85 db 0f 84 05 1a 00 00 8d 76 00 31 db 8d 65 f4 89 d8 5b 5e 5f 5d c3 8d 74 26 00 <8b> 44 90 04 85 c0 0f 85 4c fd ff ff e9 33 fd ff ff 8d b4 26 00 00 EAX: 00000010 EBX: 00000010 ECX: 00000001 EDX: 00000000 ESI: f1070040 EDI: f1070040 EBP: f1073e04 ESP: f1073de0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010097 CR0: 80050033 CR2: 00000014 CR3: 05348000 CR4: 001406b0 Call Trace: lock_acquire+0x42/0x60 ? __walk_page_range+0x4d9/0x590 _raw_spin_lock+0x22/0x40 ? __walk_page_range+0x4d9/0x590 __walk_page_range+0x4d9/0x590 walk_page_range_novma+0x57/0xa0 ptdump_walk_pgd+0x38/0x70 ptdump_walk_pgd_level_core+0x66/0x90 ? ptdump_walk_pgd_level_core+0x90/0x90 ptdump_walk_pgd_level_checkwx+0x16/0x19 mark_rodata_ro+0x95/0x9a ? rest_init+0xfb/0xfb kernel_init+0x25/0xe5 ret_from_fork+0x2e/0x38 Modules linked in: CR2: 0000000000000014 ---[ end trace 8b67ede738f0029a ]--- EIP: __lock_acquire.isra.0+0x2e8/0x4e0 Code: e8 bd a1 2f 00 85 c0 74 11 8b 1d 08 8f 26 c5 85 db 0f 84 05 1a 00 00 8d 76 00 31 db 8d 65 f4 89 d8 5b 5e 5f 5d c3 8d 74 26 00 <8b> 44 90 04 85 c0 0f 85 4c fd ff ff e9 33 fd ff ff 8d b4 26 00 00 EAX: 00000010 EBX: 00000010 ECX: 00000001 EDX: 00000000 ESI: f1070040 EDI: f1070040 EBP: f1073e04 ESP: f1073de0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00010097 CR0: 80050033 CR2: 00000014 CR3: 05348000 CR4: 001406b0 note: swapper/0[1] exited with preempt_count 1 Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 Kernel Offset: disabled ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 ]--- -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette