I have a qemu patch I'm working on which (due to a bug in that patch) asserts in kvm_arch_put_registers(). This is fine, and we come back to a command line OK. However when you run qemu again after this it seems to provoke a host kernel BUG. (This is with kvm-a15-v10.) I apologise for the intermixing of the kernel output and the output from QEMU here, which has messed up the secondary 'scheduling while atomic' bug backtrace. Has anybody else seen this one? ------------[ cut here ]------------ kernel BUG at include/linux/swapops.h:129! Internal error: Oops - BUG: 0 [#1] SMP ARM CPU: 0 Tainted: G W (3.6.0-rc1+ #74) PC is at remove_migration_pte+0x2d0/0x2dc LR is at 0x0 pc : [<c00b2390>] lr : [<00000000>] psr: 60000013 sp : deacdae8 ip : c0895b40 fp : c08c8840 r10: c04d28c0 r9 : c04a8bbc r8 : 000d5000 r7 : deac2c60 r6 : deb76000 r5 : c08beedc r4 : 0000001e r3 : c08c88c0 r2 : 0001f046 r1 : 00000000 r0 : 0009f046 Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel Control: 30c5387d Table: 9ebff180 DAC: fffffffd Process qemu-system-arm (pid: 1100, stack limit = 0xdeacc2f8) Stack: (0xdeacdae8 to 0xdeace000) dae0: c0895b40 deb766a8 000006a8 debfed08 c0895b40 c08c8840 db00: de8d8fbc 000000d5 de8d8fa0 c00b20c0 00000001 c00a3244 c08c8840 c0895b40 db20: 00000000 c08c8840 c0895b40 c00b2bc8 00000001 c08c8840 00000000 00000002 db40: c0895b40 c08c8840 c0895b40 00000000 de8d8fa1 00000001 00000000 00000002 db60: c0083514 c00b2e08 00000301 000000d5 de8d8fa0 00000001 c0083514 c00a2e24 db80: c08c8840 c08c8820 c0895b40 c08c8840 c08c8820 c0895b40 deacdc30 de8d8fa0 dba0: fffffff0 c00b3390 c0895f20 00000001 00000000 00000001 00000000 00100100 dbc0: 00200200 deacc000 00000000 00000000 00000003 00000000 c04d28c0 00000000 dbe0: deacdc30 0009f050 0009f050 deacc000 c04a8bbc 00000002 c04d28c0 c008431c dc00: 00000002 de002800 de0006c0 00000000 0009f040 0009f000 0009f400 00000004 dc20: 00080268 00000000 00000000 00000000 c08c8854 c08c8814 00000000 00000004 dc40: 00000000 00000000 00000000 00000001 ffffffff 00000000 c04c4940 00000000 dc60: 00000000 de842340 00000010 0000000f 00000010 00000040 00c00000 0009f040 dc80: 000052d0 c0219e54 0000000f de002910 dea1e600 00010000 00c00000 deacdce4 dca0: de002800 00000707 de091f4c c0016ec0 00c00000 00000000 00c00000 00000004 dcc0: de002800 00000000 0001000f c00178d0 deacdce4 00000000 00000707 00c00000 dce0: 00000000 00000001 00000001 de091f40 0000c040 00000004 de002800 0000bb80 dd00: 00000010 de003800 de002a6c c02c70e8 00000000 0000bb80 dea1e600 0000c040 dd20: de091f40 c02c6d9c 00000000 de895a54 00000002 00000000 dea1e600 c02daefc dd40: c02daea0 00000000 de002800 dea1e600 de003800 dea1e6b8 00000001 c02c0158 dd60: dea1e600 de000800 de003800 00000000 de000800 c02c10a0 de002a6c de000800 dd80: 0000000f dea1e600 00000000 00000010 c04d3a60 dea1e600 de000800 c25c4111 dda0: 00000000 00000001 00000010 00000001 de002a6c c02c1b7c de000800 00000010 ddc0: 0000bb80 c02cf1a8 deacc000 bf000000 c25c4111 00000000 00000001 c02c2bc4 dde0: de000958 de000800 dea1e600 de003400 de002800 c02cb824 00000010 de88cf00 de00: de002800 00000001 00000008 00000001 00000101 00000004 00000000 00000000 de20: 00000000 00000000 00000000 00000000 00000000 00000018 00000000 00000000 de40: 00000000 00000000 00000000 00000000 00000000 ffffffff ffffffff 00000000 de60: 00000000 00000000 00000000 00000000 00000000 de88c300 00000041 00000004 de80: de0919c0 dea1e600 deacdebc c000ec88 deacc000 00000000 001c7824 c02cc2c8 dea0: c0045004 bec75614 de0919c0 00000010 0000000d c02cc378 de88fd90 de414880 dec0: 009d0000 bec75614 de0919c0 c02ccd68 c04d2940 00000001 deacdf78 debd0000 dee0: ffffff9c ffffff9c deacc000 de9bb6a0 bec75614 de0bad80 0000000d c000ec88 df00: 00000000 c00c5c8c 00707364 00000003 debd0005 dea03a80 de874910 de4032a8 df20: de9bb6a0 00000101 00000000 de0bad88 00000000 001c7f78 de940400 00000000 df40: 00004a92 c00b4d50 00020801 debd0000 de0bad80 0000000d de0bad88 00000020 df60: deacc000 de0bad80 bec75614 c0045005 0000000d c000ec88 deacc000 00000000 df80: 001c7824 c00c61ac e0802000 00000001 bec75678 bec75664 bec75678 00261780 dfa0: 00000036 c000eb00 bec75664 bec75678 0000000d c0045005 bec75614 00000002 dfc0: bec75664 bec75678 00261780 00000036 00000000 bec756a0 001c7f78 001c7824 dfe0: 0023c254 bec755f4 0001993d b6d3d2ec 000f0010 0000000d 00000000 00000000 [<c00b2390>] (remove_migration_pte+0x2d0/0x2dc) from [<c00a3244>] (rmap_walk+0x160/0x190) [<c00a3244>] (rmap_walk+0x160/0x190) from [<c00b2e08>] (move_to_new_page+0x134/0x218) [<c00b2e08>] (move_to_new_page+0x134/0x218) from [<c00b3390>] (migrate_pages+0x324/0x3e8) [<c00b3390>] (migrate_pages+0x324/0x3e8) from [<c008431c>] (alloc_contig_range+0x140/0x420) [<c008431c>] (alloc_contig_range+0x140/0x420) from [<c0219e54>] (dma_alloc_from_contiguous+0x70/0x11c) [<c0219e54>] (dma_alloc_from_contiguous+0x70/0x11c) from [<c0016ec0>] (__alloc_from_contiguous+0x2c/0x90) [<c0016ec0>] (__alloc_from_contiguous+0x2c/0x90) from [<c00178d0>] (arm_dma_alloc+0x198/0x244) [<c00178d0>] (arm_dma_alloc+0x198/0x244) from [<c02c70e8>] (snd_dma_alloc_pages+0xd4/0x12c) [<c02c70e8>] (snd_dma_alloc_pages+0xd4/0x12c) from [<c02c6d9c>] (snd_pcm_lib_malloc_pages+0xc0/0x104) [<c02c6d9c>] (snd_pcm_lib_malloc_pages+0xc0/0x104) from [<c02daefc>] (aaci_pcm_hw_params+0x5c/0xd4) [<c02daefc>] (aaci_pcm_hw_params+0x5c/0xd4) from [<c02c0158>] (snd_pcm_hw_params+0x13c/0x3ec) [<c02c0158>] (snd_pcm_hw_params+0x13c/0x3ec) from [<c02c10a0>] (snd_pcm_common_ioctl1+0x904/0xf78) [<c02c10a0>] (snd_pcm_common_ioctl1+0x904/0xf78) from [<c02c1b7c>] (snd_pcm_playback_ioctl1+0x40/0x420) [<c02c1b7c>] (snd_pcm_playback_ioctl1+0x40/0x420) from [<c02c2bc4>] (snd_pcm_kernel_ioctl+0x40/0x6c) [<c02c2bc4>] (snd_pcm_kernel_ioctl+0x40/0x6c) from [<c02cb824>] (snd_pcm_oss_change_params+0x7f0/0xc90) [<c02cb824>] (snd_pcm_oss_change_params+0x7f0/0xc90) from [<c02cc2c8>] (snd_pcm_oss_get_active_substream+0x68/0x74) [<c02cc2c8>] (snd_pcm_oss_get_active_substream+0x68/0x74) from [<c02cc378>] (snd_pcm_oss_get_formats+0x10/0xe0) [<c02cc378>] (snd_pcm_oss_get_formats+0x10/0xe0) from [<c02ccd68>] (snd_pcm_oss_ioctl+0x280/0xc70) [<c02ccd68>] (snd_pcm_oss_ioctl+0x280/0xc70) from [<c00c5c8c>] (do_vfs_ioctl+0x80/0x568) [<c00c5c8c>] (do_vfs_ioctl+0x80/0x568) from [<c00c61ac>] (sys_ioctl+0x38/0x5c) [<c00c61ac>] (sys_ioctl+0x38/0x5c) from [<c000eb00>] (ret_fast_syscall+0x0/0x30) Code: e59dc000 e3500000 1affffb2 eaffffab (e7f001f2) ---[ end trace 1b75b31a2719ed27 ]--- x930920 idx 101note: qemu-system-arm[1100] exited with preempt_count 1 5810: OK, j=22 rBUG: scheduling while atomic: qemu-system-arm/1100/0x40000001 i=0x930a40 idx [<c0014d38>] (unwind_backtrace+0x0/0xf8) from [<c037f9d0>] (__schedule_bug+0x40/0x54) 1015826: OK, j=2[<c037f9d0>] (__schedule_bug+0x40/0x54) from [<c0383b44>] (__schedule+0x5b0/0x634) 3 ri=0x930a88 i[<c0383b44>] (__schedule+0x5b0/0x634) from [<c004e338>] (__cond_resched+0x24/0x34) dx 983168: OK, j[<c004e338>] (__cond_resched+0x24/0x34) from [<c0383cf4>] (_cond_resched+0x34/0x44) [<c0383cf4>] (_cond_resched+0x34/0x44) from [<c03830e4>] (down_read+0xc/0x18) idx 983184: OK,[<c03830e4>] (down_read+0xc/0x18) from [<c0090950>] (get_user_pages_fast+0x38/0x74) j=25 ri=0x93173[<c0090950>] (get_user_pages_fast+0x38/0x74) from [<c0063f14>] (get_futex_key+0xf0/0x1fc) 0 idx 983200: O[<c0063f14>] (get_futex_key+0xf0/0x1fc) from [<c00644d0>] (futex_wake+0x34/0x12c) K, j=26 ri=0x900[<c00644d0>] (futex_wake+0x34/0x12c) from [<c0065b28>] (do_futex+0xf4/0xad0) 068 idx 983296:[<c0065b28>] (do_futex+0xf4/0xad0) from [<c0066590>] (sys_futex+0x8c/0x168) OK, j=27 ri=0x9[<c0066590>] (sys_futex+0x8c/0x168) from [<c00273cc>] (mm_release+0xd8/0x108) 00770 idx 98342[<c00273cc>] (mm_release+0xd8/0x108) from [<c002cbe0>] (exit_mm+0x18/0x148) 4: OK, j=28 ri=0[<c002cbe0>] (exit_mm+0x18/0x148) from [<c002e5c8>] (do_exit+0x11c/0x75c) x8c4720 idx 983[<c002e5c8>] (do_exit+0x11c/0x75c) from [<c00128c0>] (die+0x1f0/0x2ac) 680: OK, j=29 ri[<c00128c0>] (die+0x1f0/0x2ac) from [<c000912c>] (do_undefinstr+0x128/0x198) =0x9006e0 idx 9[<c000912c>] (do_undefinstr+0x128/0x198) from [<c000e7ac>] (__und_svc_finish+0x0/0x14) 83696: OK, j=30 Exception stack(0xdeacdaa0 to 0xdeacdae8) ri=0x900728 idxdaa0: 0009f046 00000000 0001f046 c08c88c0 0000001e c08beedc deb76000 deac2c60 983681: not knodac0: 000d5000 c04a8bbc c04d28c0 c08c8840 c0895b40 deacdae8 00000000 c00b2390 wn to QEMU idx dae0: 60000013 ffffffff 983697: not know[<c000e7ac>] (__und_svc_finish+0x0/0x14) from [<c00b2390>] (remove_migration_pte+0x2d0/0x2dc) n to QEMU idx 9[<c00b2390>] (remove_migration_pte+0x2d0/0x2dc) from [<c00a3244>] (rmap_walk+0x160/0x190) 83808: OK, j=31 [<c00a3244>] (rmap_walk+0x160/0x190) from [<c00b2e08>] (move_to_new_page+0x134/0x218) ri=0x900848 idx[<c00b2e08>] (move_to_new_page+0x134/0x218) from [<c00b3390>] (migrate_pages+0x324/0x3e8) 983840: OK, j=3[<c00b3390>] (migrate_pages+0x324/0x3e8) from [<c008431c>] (alloc_contig_range+0x140/0x420) 2 ri=0x8fef40 i[<c008431c>] (alloc_contig_range+0x140/0x420) from [<c0219e54>] (dma_alloc_from_contiguous+0x70/0x11c) dx 986272: OK, j[<c0219e54>] (dma_alloc_from_contiguous+0x70/0x11c) from [<c0016ec0>] (__alloc_from_contiguous+0x2c/0x90) [<c0016ec0>] (__alloc_from_contiguous+0x2c/0x90) from [<c00178d0>] (arm_dma_alloc+0x198/0x244) idx 984322: ign[<c00178d0>] (arm_dma_alloc+0x198/0x244) from [<c02c70e8>] (snd_dma_alloc_pages+0xd4/0x12c) oring as WFI/NOP[<c02c70e8>] (snd_dma_alloc_pages+0xd4/0x12c) from [<c02c6d9c>] (snd_pcm_lib_malloc_pages+0xc0/0x104) idx 984338: ig[<c02c6d9c>] (snd_pcm_lib_malloc_pages+0xc0/0x104) from [<c02daefc>] (aaci_pcm_hw_params+0x5c/0xd4) noring as WFI/NO[<c02daefc>] (aaci_pcm_hw_params+0x5c/0xd4) from [<c02c0158>] (snd_pcm_hw_params+0x13c/0x3ec) P idx 984576: n[<c02c0158>] (snd_pcm_hw_params+0x13c/0x3ec) from [<c02c10a0>] (snd_pcm_common_ioctl1+0x904/0xf78) ot known to QEMU[<c02c10a0>] (snd_pcm_common_ioctl1+0x904/0xf78) from [<c02c1b7c>] (snd_pcm_playback_ioctl1+0x40/0x420) idx 984720: OK[<c02c1b7c>] (snd_pcm_playback_ioctl1+0x40/0x420) from [<c02c2bc4>] (snd_pcm_kernel_ioctl+0x40/0x6c) , j=34 ri=0x8cf7[<c02c2bc4>] (snd_pcm_kernel_ioctl+0x40/0x6c) from [<c02cb824>] (snd_pcm_oss_change_params+0x7f0/0xc90) 80 idx 984736: [<c02cb824>] (snd_pcm_oss_change_params+0x7f0/0xc90) from [<c02cc2c8>] (snd_pcm_oss_get_active_substream+0x68/0x74) OK, j=35 ri=0x90[<c02cc2c8>] (snd_pcm_oss_get_active_substream+0x68/0x74) from [<c02cc378>] (snd_pcm_oss_get_formats+0x10/0xe0) 00b0 idx 984752[<c02cc378>] (snd_pcm_oss_get_formats+0x10/0xe0) from [<c02ccd68>] (snd_pcm_oss_ioctl+0x280/0xc70) : OK, j=36 ri=0x[<c02ccd68>] (snd_pcm_oss_ioctl+0x280/0xc70) from [<c00c5c8c>] (do_vfs_ioctl+0x80/0x568) 9000f8 idx 9847[<c00c5c8c>] (do_vfs_ioctl+0x80/0x568) from [<c00c61ac>] (sys_ioctl+0x38/0x5c) 68: OK, j=37 ri=[<c00c61ac>] (sys_ioctl+0x38/0x5c) from [<c000eb00>] (ret_fast_syscall+0x0/0x30) 0x900140 -- PMM _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
