From: Toralf Förster on

Paolo Giarrusso wrote at 12:26:11
> Can you enable frame pointers to get an accurate stack trace? x86 can
Attached the .config with that function enabled, here's the output :
....
Initializing software serial port version 1
console [mc-1] enabled
ubda:
EIP: 0073:[<081bfec3>] CPU: 0 Not tainted ESP: 007b:082faaf0 EFLAGS: 00010297
Not tainted
EAX: 00000000 EBX: 180d5000 ECX: 00000001 EDX: 00000000
ESI: 181f8930 EDI: 181f4900 EBP: 082fab08 DS: 007b ES: 007b
082fa658: [<08075f5d>] show_regs+0xed/0x120
082fa674: [<0805e50e>] segv+0x25e/0x2b0
082fa72c: [<0805e5a1>] segv_handler+0x41/0x60
082fa74c: [<0806eb64>] sig_handler_common+0x54/0xa0
082fa7c8: [<0806ed07>] sig_handler+0x27/0x50
082fa7d8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fa7fc: [<080712d8>] hard_handler+0x18/0x20
082fa80c: [<b77e1400>] 0xb77e1400
082fab0c: [<081c030a>] cfq_completed_request+0x27a/0x540
082fab50: [<081b32d6>] elv_completed_request+0x76/0xe0
082fab6c: [<081b4b60>] __blk_put_request+0x30/0xc0
082fab88: [<081b4d54>] blk_finish_request+0x164/0x1c0
082fabac: [<081b50d0>] blk_end_bidi_request+0x40/0x60
082fabc4: [<081b514b>] blk_end_request+0x1b/0x20
082fabd0: [<08068c2c>] ubd_intr+0x2c/0xf0
082fabf4: [<080a83b5>] handle_IRQ_event+0x35/0xd0
082fac14: [<080a84ad>] __do_IRQ+0x5d/0xb0
082fac34: [<0805b2c5>] do_IRQ+0x25/0x40
082fac44: [<0805b4fb>] sigio_handler+0x5b/0x80
082fac5c: [<0806eb64>] sig_handler_common+0x54/0xa0
082facd8: [<0806ed07>] sig_handler+0x27/0x50
082face8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fad0c: [<080712d8>] hard_handler+0x18/0x20
082fad1c: [<b77e1400>] 0xb77e1400

Kernel panic - not syncing: Segfault with no mm
082fa640: [<08277d5b>] dump_stack+0x22/0x24
082fa658: [<08277dbe>] panic+0x61/0xdb
082fa674: [<0805e51a>] segv+0x26a/0x2b0
082fa72c: [<0805e5a1>] segv_handler+0x41/0x60
082fa74c: [<0806eb64>] sig_handler_common+0x54/0xa0
082fa7c8: [<0806ed07>] sig_handler+0x27/0x50
082fa7d8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fa7fc: [<080712d8>] hard_handler+0x18/0x20
082fa80c: [<b77e1400>] 0xb77e1400
082fab0c: [<081c030a>] cfq_completed_request+0x27a/0x540
082fab50: [<081b32d6>] elv_completed_request+0x76/0xe0
082fab6c: [<081b4b60>] __blk_put_request+0x30/0xc0
082fab88: [<081b4d54>] blk_finish_request+0x164/0x1c0
082fabac: [<081b50d0>] blk_end_bidi_request+0x40/0x60
082fabc4: [<081b514b>] blk_end_request+0x1b/0x20
082fabd0: [<08068c2c>] ubd_intr+0x2c/0xf0
082fabf4: [<080a83b5>] handle_IRQ_event+0x35/0xd0
082fac14: [<080a84ad>] __do_IRQ+0x5d/0xb0
082fac34: [<0805b2c5>] do_IRQ+0x25/0x40
082fac44: [<0805b4fb>] sigio_handler+0x5b/0x80
082fac5c: [<0806eb64>] sig_handler_common+0x54/0xa0
082facd8: [<0806ed07>] sig_handler+0x27/0x50
082face8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fad0c: [<080712d8>] hard_handler+0x18/0x20
082fad1c: [<b77e1400>] 0xb77e1400


EIP: 0000:[<00000000>] CPU: 0 Not tainted EFLAGS: 00000000
Not tainted
EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000
ESI: 00000000 EDI: 00000000 EBP: 00000000 DS: 0000 ES: 0000
082fa5f4: [<08075f5d>] show_regs+0xed/0x120
082fa610: [<0805e7dc>] panic_exit+0x2c/0x50
082fa620: [<0809928e>] notifier_call_chain+0x3e/0x70
082fa648: [<08099313>] atomic_notifier_call_chain+0x23/0x30
082fa658: [<08277de6>] panic+0x89/0xdb
082fa674: [<0805e51a>] segv+0x26a/0x2b0
082fa72c: [<0805e5a1>] segv_handler+0x41/0x60
082fa74c: [<0806eb64>] sig_handler_common+0x54/0xa0
082fa7c8: [<0806ed07>] sig_handler+0x27/0x50
082fa7d8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fa7fc: [<080712d8>] hard_handler+0x18/0x20
082fa80c: [<b77e1400>] 0xb77e1400
082fab0c: [<081c030a>] cfq_completed_request+0x27a/0x540
082fab50: [<081b32d6>] elv_completed_request+0x76/0xe0
082fab6c: [<081b4b60>] __blk_put_request+0x30/0xc0
082fab88: [<081b4d54>] blk_finish_request+0x164/0x1c0
082fabac: [<081b50d0>] blk_end_bidi_request+0x40/0x60
082fabc4: [<081b514b>] blk_end_request+0x1b/0x20
082fabd0: [<08068c2c>] ubd_intr+0x2c/0xf0
082fabf4: [<080a83b5>] handle_IRQ_event+0x35/0xd0
082fac14: [<080a84ad>] __do_IRQ+0x5d/0xb0
082fac34: [<0805b2c5>] do_IRQ+0x25/0x40
082fac44: [<0805b4fb>] sigio_handler+0x5b/0x80
082fac5c: [<0806eb64>] sig_handler_common+0x54/0xa0
082facd8: [<0806ed07>] sig_handler+0x27/0x50
082face8: [<0806ef5c>] handle_signal+0x5c/0xa0
082fad0c: [<080712d8>] hard_handler+0x18/0x20
082fad1c: [<b77e1400>] 0xb77e1400


> by people the patch works for. Say,
> $ grep HWEIGHT .config
tfoerste(a)n22 ~/devel/linux-2.6 $ grep HWEIGHT .config
CONFIG_GENERIC_HWEIGHT=y

--
MfG/Kind regards
Toralf Förster

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