On Fri, 2017-05-12 at 17:56 +0800, joeyli wrote: > On Mon, May 08, 2017 at 12:25:23PM -0700, Sai Praneeth Prakhya wrote: > > From: Sai Praneeth <[email protected]> > > > > Booting kexec kernel with "efi=old_map" in kernel command line hits > > kernel panic as shown below. > > > > [ 0.001000] BUG: unable to handle kernel paging request at > > ffff88007fe78070 > > [ 0.001000] IP: virt_efi_set_variable.part.7+0x63/0x1b0 > > [ 0.001000] PGD 7ea28067 > > [ 0.001000] PUD 7ea2b067 > > [ 0.001000] PMD 7ea2d067 > > [ 0.001000] PTE 0 > > [ 0.001000] > > [ 0.001000] Oops: 0000 [#1] SMP > > [ 0.001000] Modules linked in: > > [ 0.001000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted > > 4.11.0-rc2-yocto-standard+ #229 > > [ 0.001000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS > > 0.0.0 02/06/2015 > > [ 0.001000] task: ffffffff82022500 task.stack: ffffffff82000000 > > [ 0.001000] RIP: 0010:virt_efi_set_variable.part.7+0x63/0x1b0 > > [ 0.001000] RSP: 0000:ffffffff82003dc0 EFLAGS: 00010246 > > [ 0.001000] RAX: ffff88007fe78018 RBX: ffffffff82050300 RCX: > > 0000000000000007 > > [ 0.001000] RDX: ffffffff82003e50 RSI: ffffffff82050300 RDI: > > ffffffff82050300 > > [ 0.001000] RBP: ffffffff82003e08 R08: 0000000000000000 R09: > > 0000000000000000 > > [ 0.001000] R10: 0000000000000000 R11: 0000000000000000 R12: > > ffffffff82003e50 > > [ 0.001000] R13: 0000000000000007 R14: 0000000000000246 R15: > > 0000000000000000 > > [ 0.001000] FS: 0000000000000000(0000) GS:ffff88007fa00000(0000) > > knlGS:0000000000000000 > > [ 0.001000] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > [ 0.001000] CR2: ffff88007fe78070 CR3: 000000007da1d000 CR4: > > 00000000000006b0 > > [ 0.001000] DR0: 0000000000000000 DR1: 0000000000000000 DR2: > > 0000000000000000 > > [ 0.001000] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: > > 0000000000000400 > > [ 0.001000] Call Trace: > > [ 0.001000] virt_efi_set_variable+0x5d/0x70 > > [ 0.001000] efi_delete_dummy_variable+0x7a/0x80 > > [ 0.001000] efi_enter_virtual_mode+0x3f6/0x4a7 > > [ 0.001000] start_kernel+0x375/0x400 > > [ 0.001000] x86_64_start_reservations+0x2a/0x2c > > [ 0.001000] x86_64_start_kernel+0x168/0x176 > > [ 0.001000] start_cpu+0x14/0x14 > > [ 0.001000] Code: 04 b0 84 ff 80 3d c5 56 b3 00 00 4c 8b 44 24 08 75 > > 6b 9c 41 5e 48 8b 05 9c 78 99 00 4d 89 c1 48 89 de 4d 89 f8 44 89 e9 4c > > 89 e2 <48> 8b 40 58 48 8b 78 58 e8 b0 2d 88 ff 48 c7 c6 b6 1d f4 81 4c > > [ 0.001000] RIP: virt_efi_set_variable.part.7+0x63/0x1b0 RSP: > > ffffffff82003dc0 > > [ 0.001000] CR2: ffff88007fe78070 > > [ 0.001000] ---[ end trace 0000000000000000 ]--- > > [ 0.001000] Kernel panic - not syncing: Attempted to kill the idle task! > > [ 0.001000] ---[ end Kernel panic - not syncing: Attempted to kill the > > idle task! > > > > This happens because efi=old_map doesn't use efi_pgd but rather it uses > > kernel's pgd. We don't hit the same panic in a regular kernel because > > it uses old_map_region() and not __map_region(). > > > > This issue can be reproduced on OVMF. This patch works to fix > problem. > > Tested-by: Lee, Chun-Yi <[email protected]> >
Thanks a lot! Joey, for testing the patch. Regards, Sai
