Jens,
This is freshly after booting into this morning's kernel:
[ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
[ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
[ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
[ 60.656154] Oops: 0000 [1] SMP
[ 60.656157] CPU 1
[ 60.656159] Modules linked in: sbp2 lp dvb_pll lgdt330x cx88_dvb cx88_vp3054_i2c videobuf_dvb tuner tea5767 td
a8290 tuner_simple mt20xx cx88_alsa cx8802 cx8800 cx88xx ir_common tveeprom videobuf_dma_sg videobuf_core btcx_ri
sc i2c_nforce2 evdev rtc forcedeth ehci_hcd fuse
[ 60.656176] Pid: 4250, comm: hald-probe-stor Not tainted 2.6.24-rc0-5 #1
[ 60.656178] RIP: 0010:[<ffffffff80375553>] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
[ 60.656182] RSP: 0018:ffff810004791930 EFLAGS: 00010246
[ 60.656184] RAX: 000000000403b000 RBX: 0000000000001000 RCX: 6db6db6db6db6db7
[ 60.656187] RDX: 0000000000000000 RSI: ffff810001000000 RDI: 0000000005701000
[ 60.656189] RBP: ffff810004791968 R08: 0000000005700000 R09: ffff8100044aa060
[ 60.656191] R10: 0000000000000000 R11: ffff8100050dea00 R12: 0000000000002000
[ 60.656193] R13: ffff8100060d2700 R14: 0000000000000000 R15: ffffffff807f0000
[ 60.656196] FS: 00002b5da088e6e0(0000) GS:ffff810003011500(0000) knlGS:0000000000000000
[ 60.656198] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 60.656200] CR2: 0000000000000000 CR3: 0000000004568000 CR4: 00000000000006e0
[ 60.656202] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 60.656204] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 60.656207] Process hald-probe-stor (pid: 4250, threadinfo ffff810004790000, task ffff810006312000)
[ 60.656208] Stack: ffff81000607a000 0000000100000001 ffff8100040fa120 ffffffff807fe2c0
[ 60.656213] ffff81000607a000 ffff81000607a000 ffffffff807fe2c0 ffff8100047919a8
[ 60.656217] ffffffff8041bb58 ffff8100047919a8 ffff8100040fa120 ffffffff807fe2c0
[ 60.656220] Call Trace:
[ 60.656226] [<ffffffff8041bb58>] ide_map_sg+0x38/0xb0
[ 60.656231] [<ffffffff8042952b>] cdrom_start_read_continuation+0x0/0xb5
[ 60.656234] [<ffffffff80423806>] ide_build_sglist+0x38/0x88
[ 60.656238] [<ffffffff80423885>] ide_build_dmatable+0x2f/0x172
[ 60.656241] [<ffffffff804239fc>] ide_dma_setup+0x34/0xaa
[ 60.656245] [<ffffffff804277e5>] cdrom_start_packet_command+0x5a/0x177
[ 60.656249] [<ffffffff8037fac4>] cfq_dispatch_insert+0x38/0x50
[ 60.656253] [<ffffffff80428339>] ide_do_rw_cdrom+0x423/0x57c
[ 60.656257] [<ffffffff8041c56c>] ide_do_request+0x7a7/0xa74
[ 60.656263] [<ffffffff8023c097>] del_timer+0x52/0x5d
[ 60.656267] [<ffffffff8025d343>] sync_page+0x0/0x45
[ 60.656269] [<ffffffff8041cba0>] do_ide_request+0x1b/0x1d
[ 60.656273] [<ffffffff803778a7>] __generic_unplug_device+0x28/0x2c
[ 60.656276] [<ffffffff80377c6e>] generic_unplug_device+0x20/0x31
[ 60.656279] [<ffffffff803751b1>] blk_backing_dev_unplug+0x16/0x18
[ 60.656283] [<ffffffff8029decc>] block_sync_page+0x42/0x44
[ 60.656285] [<ffffffff8025d37f>] sync_page+0x3c/0x45
[ 60.656290] [<ffffffff805589b8>] __wait_on_bit_lock+0x42/0x79
[ 60.656294] [<ffffffff8025d32f>] __lock_page+0x64/0x6b
[ 60.656298] [<ffffffff8024664b>] wake_bit_function+0x0/0x2a
[ 60.656301] [<ffffffff8025da95>] do_generic_mapping_read+0x1da/0x383
[ 60.656304] [<ffffffff8025d08d>] file_read_actor+0x0/0x137
[ 60.656309] [<ffffffff8025f1af>] generic_file_aio_read+0x11e/0x15d
[ 60.656315] [<ffffffff8027ee59>] do_sync_read+0xe2/0x126
[ 60.656318] [<ffffffff8026b15a>] handle_mm_fault+0x62e/0x65e
[ 60.656324] [<ffffffff80386fcc>] __up_read+0x8f/0x97
[ 60.656327] [<ffffffff80246613>] autoremove_wake_function+0x0/0x38
[ 60.656331] [<ffffffff80559233>] __mutex_lock_slowpath+0x22f/0x23c
[ 60.656337] [<ffffffff8027f5f0>] vfs_read+0xab/0x134
[ 60.656341] [<ffffffff8027f9b5>] sys_read+0x47/0x6f
[ 60.656345] [<ffffffff8020b77e>] system_call+0x7e/0x83
[ 60.656349]
[ 60.656350]
[ 60.656350] Code: 49 8b 02 41 c7 42 18 00 00 00 00 49 c7 42 10 00 00 00 00 83
[ 60.656359] RIP [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
[ 60.656362] RSP <ffff810004791930>
[ 60.656363] CR2: 0000000000000000
Platform is AMD64 and the userspace is Ubuntu 7/10 Gutsy Gibbon.
florin
--
Bruce Schneier expects the Spanish Inquisition.
http://geekz.co.uk/schneierfacts/fact/163
On Tue, Oct 23 2007, Florin Iucha wrote:
> Jens,
>
> This is freshly after booting into this morning's kernel:
>
> [ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
> [ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> [ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
> [ 60.656154] Oops: 0000 [1] SMP
> [ 60.656157] CPU 1
> [ 60.656159] Modules linked in: sbp2 lp dvb_pll lgdt330x cx88_dvb cx88_vp3054_i2c videobuf_dvb tuner tea5767 td
> a8290 tuner_simple mt20xx cx88_alsa cx8802 cx8800 cx88xx ir_common tveeprom videobuf_dma_sg videobuf_core btcx_ri
> sc i2c_nforce2 evdev rtc forcedeth ehci_hcd fuse
> [ 60.656176] Pid: 4250, comm: hald-probe-stor Not tainted 2.6.24-rc0-5 #1
> [ 60.656178] RIP: 0010:[<ffffffff80375553>] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> [ 60.656182] RSP: 0018:ffff810004791930 EFLAGS: 00010246
> [ 60.656184] RAX: 000000000403b000 RBX: 0000000000001000 RCX: 6db6db6db6db6db7
> [ 60.656187] RDX: 0000000000000000 RSI: ffff810001000000 RDI: 0000000005701000
> [ 60.656189] RBP: ffff810004791968 R08: 0000000005700000 R09: ffff8100044aa060
> [ 60.656191] R10: 0000000000000000 R11: ffff8100050dea00 R12: 0000000000002000
> [ 60.656193] R13: ffff8100060d2700 R14: 0000000000000000 R15: ffffffff807f0000
> [ 60.656196] FS: 00002b5da088e6e0(0000) GS:ffff810003011500(0000) knlGS:0000000000000000
> [ 60.656198] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> [ 60.656200] CR2: 0000000000000000 CR3: 0000000004568000 CR4: 00000000000006e0
> [ 60.656202] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [ 60.656204] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> [ 60.656207] Process hald-probe-stor (pid: 4250, threadinfo ffff810004790000, task ffff810006312000)
> [ 60.656208] Stack: ffff81000607a000 0000000100000001 ffff8100040fa120 ffffffff807fe2c0
> [ 60.656213] ffff81000607a000 ffff81000607a000 ffffffff807fe2c0 ffff8100047919a8
> [ 60.656217] ffffffff8041bb58 ffff8100047919a8 ffff8100040fa120 ffffffff807fe2c0
> [ 60.656220] Call Trace:
> [ 60.656226] [<ffffffff8041bb58>] ide_map_sg+0x38/0xb0
> [ 60.656231] [<ffffffff8042952b>] cdrom_start_read_continuation+0x0/0xb5
> [ 60.656234] [<ffffffff80423806>] ide_build_sglist+0x38/0x88
> [ 60.656238] [<ffffffff80423885>] ide_build_dmatable+0x2f/0x172
> [ 60.656241] [<ffffffff804239fc>] ide_dma_setup+0x34/0xaa
> [ 60.656245] [<ffffffff804277e5>] cdrom_start_packet_command+0x5a/0x177
> [ 60.656249] [<ffffffff8037fac4>] cfq_dispatch_insert+0x38/0x50
> [ 60.656253] [<ffffffff80428339>] ide_do_rw_cdrom+0x423/0x57c
> [ 60.656257] [<ffffffff8041c56c>] ide_do_request+0x7a7/0xa74
> [ 60.656263] [<ffffffff8023c097>] del_timer+0x52/0x5d
> [ 60.656267] [<ffffffff8025d343>] sync_page+0x0/0x45
> [ 60.656269] [<ffffffff8041cba0>] do_ide_request+0x1b/0x1d
> [ 60.656273] [<ffffffff803778a7>] __generic_unplug_device+0x28/0x2c
> [ 60.656276] [<ffffffff80377c6e>] generic_unplug_device+0x20/0x31
> [ 60.656279] [<ffffffff803751b1>] blk_backing_dev_unplug+0x16/0x18
> [ 60.656283] [<ffffffff8029decc>] block_sync_page+0x42/0x44
> [ 60.656285] [<ffffffff8025d37f>] sync_page+0x3c/0x45
> [ 60.656290] [<ffffffff805589b8>] __wait_on_bit_lock+0x42/0x79
> [ 60.656294] [<ffffffff8025d32f>] __lock_page+0x64/0x6b
> [ 60.656298] [<ffffffff8024664b>] wake_bit_function+0x0/0x2a
> [ 60.656301] [<ffffffff8025da95>] do_generic_mapping_read+0x1da/0x383
> [ 60.656304] [<ffffffff8025d08d>] file_read_actor+0x0/0x137
> [ 60.656309] [<ffffffff8025f1af>] generic_file_aio_read+0x11e/0x15d
> [ 60.656315] [<ffffffff8027ee59>] do_sync_read+0xe2/0x126
> [ 60.656318] [<ffffffff8026b15a>] handle_mm_fault+0x62e/0x65e
> [ 60.656324] [<ffffffff80386fcc>] __up_read+0x8f/0x97
> [ 60.656327] [<ffffffff80246613>] autoremove_wake_function+0x0/0x38
> [ 60.656331] [<ffffffff80559233>] __mutex_lock_slowpath+0x22f/0x23c
> [ 60.656337] [<ffffffff8027f5f0>] vfs_read+0xab/0x134
> [ 60.656341] [<ffffffff8027f9b5>] sys_read+0x47/0x6f
> [ 60.656345] [<ffffffff8020b77e>] system_call+0x7e/0x83
> [ 60.656349]
> [ 60.656350]
> [ 60.656350] Code: 49 8b 02 41 c7 42 18 00 00 00 00 49 c7 42 10 00 00 00 00 83
> [ 60.656359] RIP [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> [ 60.656362] RSP <ffff810004791930>
> [ 60.656363] CR2: 0000000000000000
>
> Platform is AMD64 and the userspace is Ubuntu 7/10 Gutsy Gibbon.
This should fix it, sorry about that.
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 61c2e39..de5ba47 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -1351,11 +1351,21 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
new_segment:
if (!sg)
sg = sglist;
- else
+ else {
+ /*
+ * If the driver previously mapped a shorter
+ * list, we could see a termination bit
+ * prematurely unless it fully inits the sg
+ * table on each mapping. We KNOW that there
+ * must be more entries here or the driver
+ * would be buggy, so force clear the
+ * termination bit to avoid doing a full
+ * sg_init_table() in drivers for each command.
+ */
+ sg->page_link &= ~0x02;
sg = sg_next(sg);
+ }
- sg_dma_len(sg) = 0;
- sg_dma_address(sg) = 0;
sg_set_page(sg, bvec->bv_page);
sg->length = nbytes;
sg->offset = bvec->bv_offset;
--
Jens Axboe
On Tue, Oct 23 2007, Florin Iucha wrote:
> On Tue, Oct 23, 2007 at 07:46:37AM -0500, Florin Iucha wrote:
> > [ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
> > [ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > [ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
> > [ 60.656154] Oops: 0000 [1] SMP
> > [ 60.656157] CPU 1
> > ...
>
> There was a DVD in the drive. After the OOPS, I cannot eject it
> via the button, and the "eject" command is stuck in "D" state:
>
> [ 436.308282] eject D ffffffff80571760 0 5336 5324
> [ 436.308285] ffff810007c35d08 0000000000000082 0000000000000000 ffff810007c35ca8
> [ 436.308288] ffff810006fb15f0 ffff810003062000 ffff810006fb17f8 0000000122222222
> [ 436.308292] 0000000000000003 ffff8100057e1070 0000000000000000 0000000000000000
> [ 436.308295] Call Trace:
> [ 436.308301] [<ffffffff80559137>] __mutex_lock_slowpath+0x133/0x23c
> [ 436.308306] [<ffffffff80559259>] mutex_lock+0x19/0x1d
> [ 436.308309] [<ffffffff802a35a0>] do_open+0x74/0x2d1
> [ 436.308313] [<ffffffff802a3a02>] blkdev_open+0x0/0x69
> [ 436.308315] [<ffffffff802a3a39>] blkdev_open+0x37/0x69
> [ 436.308319] [<ffffffff8027d68e>] __dentry_open+0xe6/0x1bd
> [ 436.308323] [<ffffffff8027d7fd>] nameidata_to_filp+0x2d/0x3f
> [ 436.308326] [<ffffffff8027d848>] do_filp_open+0x39/0x4b
> [ 436.308330] [<ffffffff8055a16d>] _spin_unlock+0x9/0xb
> [ 436.308333] [<ffffffff8027d58d>] get_unused_fd_flags+0x113/0x121
> [ 436.308337] [<ffffffff8027d8ab>] do_sys_open+0x51/0xd9
> [ 436.308341] [<ffffffff8027d95c>] sys_open+0x1b/0x1d
> [ 436.308343] [<ffffffff8020b77e>] system_call+0x7e/0x83
That's expected, the queue is hosed at that point.
--
Jens Axboe
On Tue, Oct 23, 2007 at 07:46:37AM -0500, Florin Iucha wrote:
> [ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
> [ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> [ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
> [ 60.656154] Oops: 0000 [1] SMP
> [ 60.656157] CPU 1
> ...
There was a DVD in the drive. After the OOPS, I cannot eject it
via the button, and the "eject" command is stuck in "D" state:
[ 436.308282] eject D ffffffff80571760 0 5336 5324
[ 436.308285] ffff810007c35d08 0000000000000082 0000000000000000 ffff810007c35ca8
[ 436.308288] ffff810006fb15f0 ffff810003062000 ffff810006fb17f8 0000000122222222
[ 436.308292] 0000000000000003 ffff8100057e1070 0000000000000000 0000000000000000
[ 436.308295] Call Trace:
[ 436.308301] [<ffffffff80559137>] __mutex_lock_slowpath+0x133/0x23c
[ 436.308306] [<ffffffff80559259>] mutex_lock+0x19/0x1d
[ 436.308309] [<ffffffff802a35a0>] do_open+0x74/0x2d1
[ 436.308313] [<ffffffff802a3a02>] blkdev_open+0x0/0x69
[ 436.308315] [<ffffffff802a3a39>] blkdev_open+0x37/0x69
[ 436.308319] [<ffffffff8027d68e>] __dentry_open+0xe6/0x1bd
[ 436.308323] [<ffffffff8027d7fd>] nameidata_to_filp+0x2d/0x3f
[ 436.308326] [<ffffffff8027d848>] do_filp_open+0x39/0x4b
[ 436.308330] [<ffffffff8055a16d>] _spin_unlock+0x9/0xb
[ 436.308333] [<ffffffff8027d58d>] get_unused_fd_flags+0x113/0x121
[ 436.308337] [<ffffffff8027d8ab>] do_sys_open+0x51/0xd9
[ 436.308341] [<ffffffff8027d95c>] sys_open+0x1b/0x1d
[ 436.308343] [<ffffffff8020b77e>] system_call+0x7e/0x83
florin
--
Bruce Schneier expects the Spanish Inquisition.
http://geekz.co.uk/schneierfacts/fact/163
Hi Jens,
On Tue, 23 Oct 2007 14:47:38 +0200, Jens Axboe wrote:
> On Tue, Oct 23 2007, Florin Iucha wrote:
> > Jens,
> >
> > This is freshly after booting into this morning's kernel:
> >
> > [ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
> > [ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > [ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
> > [ 60.656154] Oops: 0000 [1] SMP
> > [ 60.656157] CPU 1
> > [ 60.656159] Modules linked in: sbp2 lp dvb_pll lgdt330x cx88_dvb cx88_vp3054_i2c videobuf_dvb tuner tea5767 td
> > a8290 tuner_simple mt20xx cx88_alsa cx8802 cx8800 cx88xx ir_common tveeprom videobuf_dma_sg videobuf_core btcx_ri
> > sc i2c_nforce2 evdev rtc forcedeth ehci_hcd fuse
> > [ 60.656176] Pid: 4250, comm: hald-probe-stor Not tainted 2.6.24-rc0-5 #1
> > [ 60.656178] RIP: 0010:[<ffffffff80375553>] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > [ 60.656182] RSP: 0018:ffff810004791930 EFLAGS: 00010246
> > [ 60.656184] RAX: 000000000403b000 RBX: 0000000000001000 RCX: 6db6db6db6db6db7
> > [ 60.656187] RDX: 0000000000000000 RSI: ffff810001000000 RDI: 0000000005701000
> > [ 60.656189] RBP: ffff810004791968 R08: 0000000005700000 R09: ffff8100044aa060
> > [ 60.656191] R10: 0000000000000000 R11: ffff8100050dea00 R12: 0000000000002000
> > [ 60.656193] R13: ffff8100060d2700 R14: 0000000000000000 R15: ffffffff807f0000
> > [ 60.656196] FS: 00002b5da088e6e0(0000) GS:ffff810003011500(0000) knlGS:0000000000000000
> > [ 60.656198] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> > [ 60.656200] CR2: 0000000000000000 CR3: 0000000004568000 CR4: 00000000000006e0
> > [ 60.656202] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > [ 60.656204] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > [ 60.656207] Process hald-probe-stor (pid: 4250, threadinfo ffff810004790000, task ffff810006312000)
> > [ 60.656208] Stack: ffff81000607a000 0000000100000001 ffff8100040fa120 ffffffff807fe2c0
> > [ 60.656213] ffff81000607a000 ffff81000607a000 ffffffff807fe2c0 ffff8100047919a8
> > [ 60.656217] ffffffff8041bb58 ffff8100047919a8 ffff8100040fa120 ffffffff807fe2c0
> > [ 60.656220] Call Trace:
> > [ 60.656226] [<ffffffff8041bb58>] ide_map_sg+0x38/0xb0
> > [ 60.656231] [<ffffffff8042952b>] cdrom_start_read_continuation+0x0/0xb5
> > [ 60.656234] [<ffffffff80423806>] ide_build_sglist+0x38/0x88
> > [ 60.656238] [<ffffffff80423885>] ide_build_dmatable+0x2f/0x172
> > [ 60.656241] [<ffffffff804239fc>] ide_dma_setup+0x34/0xaa
> > [ 60.656245] [<ffffffff804277e5>] cdrom_start_packet_command+0x5a/0x177
> > [ 60.656249] [<ffffffff8037fac4>] cfq_dispatch_insert+0x38/0x50
> > [ 60.656253] [<ffffffff80428339>] ide_do_rw_cdrom+0x423/0x57c
> > [ 60.656257] [<ffffffff8041c56c>] ide_do_request+0x7a7/0xa74
> > [ 60.656263] [<ffffffff8023c097>] del_timer+0x52/0x5d
> > [ 60.656267] [<ffffffff8025d343>] sync_page+0x0/0x45
> > [ 60.656269] [<ffffffff8041cba0>] do_ide_request+0x1b/0x1d
> > [ 60.656273] [<ffffffff803778a7>] __generic_unplug_device+0x28/0x2c
> > [ 60.656276] [<ffffffff80377c6e>] generic_unplug_device+0x20/0x31
> > [ 60.656279] [<ffffffff803751b1>] blk_backing_dev_unplug+0x16/0x18
> > [ 60.656283] [<ffffffff8029decc>] block_sync_page+0x42/0x44
> > [ 60.656285] [<ffffffff8025d37f>] sync_page+0x3c/0x45
> > [ 60.656290] [<ffffffff805589b8>] __wait_on_bit_lock+0x42/0x79
> > [ 60.656294] [<ffffffff8025d32f>] __lock_page+0x64/0x6b
> > [ 60.656298] [<ffffffff8024664b>] wake_bit_function+0x0/0x2a
> > [ 60.656301] [<ffffffff8025da95>] do_generic_mapping_read+0x1da/0x383
> > [ 60.656304] [<ffffffff8025d08d>] file_read_actor+0x0/0x137
> > [ 60.656309] [<ffffffff8025f1af>] generic_file_aio_read+0x11e/0x15d
> > [ 60.656315] [<ffffffff8027ee59>] do_sync_read+0xe2/0x126
> > [ 60.656318] [<ffffffff8026b15a>] handle_mm_fault+0x62e/0x65e
> > [ 60.656324] [<ffffffff80386fcc>] __up_read+0x8f/0x97
> > [ 60.656327] [<ffffffff80246613>] autoremove_wake_function+0x0/0x38
> > [ 60.656331] [<ffffffff80559233>] __mutex_lock_slowpath+0x22f/0x23c
> > [ 60.656337] [<ffffffff8027f5f0>] vfs_read+0xab/0x134
> > [ 60.656341] [<ffffffff8027f9b5>] sys_read+0x47/0x6f
> > [ 60.656345] [<ffffffff8020b77e>] system_call+0x7e/0x83
> > [ 60.656349]
> > [ 60.656350]
> > [ 60.656350] Code: 49 8b 02 41 c7 42 18 00 00 00 00 49 c7 42 10 00 00 00 00 83
> > [ 60.656359] RIP [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > [ 60.656362] RSP <ffff810004791930>
> > [ 60.656363] CR2: 0000000000000000
> >
> > Platform is AMD64 and the userspace is Ubuntu 7/10 Gutsy Gibbon.
I am seeing something similar with 2.6.23-git18 on x86_64 at boot time.
2.6.23-git16 was working fine.
> This should fix it, sorry about that.
>
> diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
> index 61c2e39..de5ba47 100644
> --- a/block/ll_rw_blk.c
> +++ b/block/ll_rw_blk.c
> @@ -1351,11 +1351,21 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
> new_segment:
> if (!sg)
> sg = sglist;
> - else
> + else {
> + /*
> + * If the driver previously mapped a shorter
> + * list, we could see a termination bit
> + * prematurely unless it fully inits the sg
> + * table on each mapping. We KNOW that there
> + * must be more entries here or the driver
> + * would be buggy, so force clear the
> + * termination bit to avoid doing a full
> + * sg_init_table() in drivers for each command.
> + */
> + sg->page_link &= ~0x02;
> sg = sg_next(sg);
> + }
>
> - sg_dma_len(sg) = 0;
> - sg_dma_address(sg) = 0;
> sg_set_page(sg, bvec->bv_page);
> sg->length = nbytes;
> sg->offset = bvec->bv_offset;
>
>
The patch above indeed fixes the problem for me, as far as I can see.
Thanks Jens! Can you please push this fix to Linus quickly?
--
Jean Delvare
On Tue, Oct 23 2007, Jean Delvare wrote:
> Hi Jens,
>
> On Tue, 23 Oct 2007 14:47:38 +0200, Jens Axboe wrote:
> > On Tue, Oct 23 2007, Florin Iucha wrote:
> > > Jens,
> > >
> > > This is freshly after booting into this morning's kernel:
> > >
> > > [ 60.656136] Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP:
> > > [ 60.656143] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > > [ 60.656151] PGD 4640067 PUD 46d4067 PMD 0
> > > [ 60.656154] Oops: 0000 [1] SMP
> > > [ 60.656157] CPU 1
> > > [ 60.656159] Modules linked in: sbp2 lp dvb_pll lgdt330x cx88_dvb cx88_vp3054_i2c videobuf_dvb tuner tea5767 td
> > > a8290 tuner_simple mt20xx cx88_alsa cx8802 cx8800 cx88xx ir_common tveeprom videobuf_dma_sg videobuf_core btcx_ri
> > > sc i2c_nforce2 evdev rtc forcedeth ehci_hcd fuse
> > > [ 60.656176] Pid: 4250, comm: hald-probe-stor Not tainted 2.6.24-rc0-5 #1
> > > [ 60.656178] RIP: 0010:[<ffffffff80375553>] [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > > [ 60.656182] RSP: 0018:ffff810004791930 EFLAGS: 00010246
> > > [ 60.656184] RAX: 000000000403b000 RBX: 0000000000001000 RCX: 6db6db6db6db6db7
> > > [ 60.656187] RDX: 0000000000000000 RSI: ffff810001000000 RDI: 0000000005701000
> > > [ 60.656189] RBP: ffff810004791968 R08: 0000000005700000 R09: ffff8100044aa060
> > > [ 60.656191] R10: 0000000000000000 R11: ffff8100050dea00 R12: 0000000000002000
> > > [ 60.656193] R13: ffff8100060d2700 R14: 0000000000000000 R15: ffffffff807f0000
> > > [ 60.656196] FS: 00002b5da088e6e0(0000) GS:ffff810003011500(0000) knlGS:0000000000000000
> > > [ 60.656198] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> > > [ 60.656200] CR2: 0000000000000000 CR3: 0000000004568000 CR4: 00000000000006e0
> > > [ 60.656202] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> > > [ 60.656204] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
> > > [ 60.656207] Process hald-probe-stor (pid: 4250, threadinfo ffff810004790000, task ffff810006312000)
> > > [ 60.656208] Stack: ffff81000607a000 0000000100000001 ffff8100040fa120 ffffffff807fe2c0
> > > [ 60.656213] ffff81000607a000 ffff81000607a000 ffffffff807fe2c0 ffff8100047919a8
> > > [ 60.656217] ffffffff8041bb58 ffff8100047919a8 ffff8100040fa120 ffffffff807fe2c0
> > > [ 60.656220] Call Trace:
> > > [ 60.656226] [<ffffffff8041bb58>] ide_map_sg+0x38/0xb0
> > > [ 60.656231] [<ffffffff8042952b>] cdrom_start_read_continuation+0x0/0xb5
> > > [ 60.656234] [<ffffffff80423806>] ide_build_sglist+0x38/0x88
> > > [ 60.656238] [<ffffffff80423885>] ide_build_dmatable+0x2f/0x172
> > > [ 60.656241] [<ffffffff804239fc>] ide_dma_setup+0x34/0xaa
> > > [ 60.656245] [<ffffffff804277e5>] cdrom_start_packet_command+0x5a/0x177
> > > [ 60.656249] [<ffffffff8037fac4>] cfq_dispatch_insert+0x38/0x50
> > > [ 60.656253] [<ffffffff80428339>] ide_do_rw_cdrom+0x423/0x57c
> > > [ 60.656257] [<ffffffff8041c56c>] ide_do_request+0x7a7/0xa74
> > > [ 60.656263] [<ffffffff8023c097>] del_timer+0x52/0x5d
> > > [ 60.656267] [<ffffffff8025d343>] sync_page+0x0/0x45
> > > [ 60.656269] [<ffffffff8041cba0>] do_ide_request+0x1b/0x1d
> > > [ 60.656273] [<ffffffff803778a7>] __generic_unplug_device+0x28/0x2c
> > > [ 60.656276] [<ffffffff80377c6e>] generic_unplug_device+0x20/0x31
> > > [ 60.656279] [<ffffffff803751b1>] blk_backing_dev_unplug+0x16/0x18
> > > [ 60.656283] [<ffffffff8029decc>] block_sync_page+0x42/0x44
> > > [ 60.656285] [<ffffffff8025d37f>] sync_page+0x3c/0x45
> > > [ 60.656290] [<ffffffff805589b8>] __wait_on_bit_lock+0x42/0x79
> > > [ 60.656294] [<ffffffff8025d32f>] __lock_page+0x64/0x6b
> > > [ 60.656298] [<ffffffff8024664b>] wake_bit_function+0x0/0x2a
> > > [ 60.656301] [<ffffffff8025da95>] do_generic_mapping_read+0x1da/0x383
> > > [ 60.656304] [<ffffffff8025d08d>] file_read_actor+0x0/0x137
> > > [ 60.656309] [<ffffffff8025f1af>] generic_file_aio_read+0x11e/0x15d
> > > [ 60.656315] [<ffffffff8027ee59>] do_sync_read+0xe2/0x126
> > > [ 60.656318] [<ffffffff8026b15a>] handle_mm_fault+0x62e/0x65e
> > > [ 60.656324] [<ffffffff80386fcc>] __up_read+0x8f/0x97
> > > [ 60.656327] [<ffffffff80246613>] autoremove_wake_function+0x0/0x38
> > > [ 60.656331] [<ffffffff80559233>] __mutex_lock_slowpath+0x22f/0x23c
> > > [ 60.656337] [<ffffffff8027f5f0>] vfs_read+0xab/0x134
> > > [ 60.656341] [<ffffffff8027f9b5>] sys_read+0x47/0x6f
> > > [ 60.656345] [<ffffffff8020b77e>] system_call+0x7e/0x83
> > > [ 60.656349]
> > > [ 60.656350]
> > > [ 60.656350] Code: 49 8b 02 41 c7 42 18 00 00 00 00 49 c7 42 10 00 00 00 00 83
> > > [ 60.656359] RIP [<ffffffff80375553>] blk_rq_map_sg+0x10d/0x17c
> > > [ 60.656362] RSP <ffff810004791930>
> > > [ 60.656363] CR2: 0000000000000000
> > >
> > > Platform is AMD64 and the userspace is Ubuntu 7/10 Gutsy Gibbon.
>
> I am seeing something similar with 2.6.23-git18 on x86_64 at boot time.
> 2.6.23-git16 was working fine.
>
> > This should fix it, sorry about that.
> >
> > diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
> > index 61c2e39..de5ba47 100644
> > --- a/block/ll_rw_blk.c
> > +++ b/block/ll_rw_blk.c
> > @@ -1351,11 +1351,21 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
> > new_segment:
> > if (!sg)
> > sg = sglist;
> > - else
> > + else {
> > + /*
> > + * If the driver previously mapped a shorter
> > + * list, we could see a termination bit
> > + * prematurely unless it fully inits the sg
> > + * table on each mapping. We KNOW that there
> > + * must be more entries here or the driver
> > + * would be buggy, so force clear the
> > + * termination bit to avoid doing a full
> > + * sg_init_table() in drivers for each command.
> > + */
> > + sg->page_link &= ~0x02;
> > sg = sg_next(sg);
> > + }
> >
> > - sg_dma_len(sg) = 0;
> > - sg_dma_address(sg) = 0;
> > sg_set_page(sg, bvec->bv_page);
> > sg->length = nbytes;
> > sg->offset = bvec->bv_offset;
> >
> >
>
> The patch above indeed fixes the problem for me, as far as I can see.
> Thanks Jens! Can you please push this fix to Linus quickly?
It's already pushed and pulled, so current git should work again...
--
Jens Axboe