Wen Congyang b853fd3648 ext4: avoid null dereference in trace_ext4_mballoc_discard ... ac->inode is set to null in function ext4_mb_release_group_pa(), and then trace_ext4_mballoc_discard(ac) is called, the kernel will panic. BUG: unable to handle kernel NULL pointer dereference at 000000a4 IP: [<f87e1714>] ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4] *pdpt = 0000000000abd001 *pde = 0000000000000000 Oops: 0000 [#1] SMP Pid: 550, comm: flush-8:16 Not tainted 2.6.36-rc1 #1 SE7320EP2/Altos G530 EIP: 0060:[<f87e1714>] EFLAGS: 00010206 CPU: 1 EIP is at ftrace_raw_event_ext4__mballoc+0x54/0xc0 [ext4] EAX: f32ac840 EBX: f3f1cf88 ECX: f32ac840 EDX: 00000000 ESI: f32ac83c EDI: f880b9d8 EBP: 00000000 ESP: f4b77ae4 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process flush-8:16 (pid: 550, ti=f4b76000 task=f613e540 task.ti=f4b76000) Call Trace: [<f87f5ac1>] ? ext4_mb_release_group_pa+0x121/0x150 [ext4] [<f87f8356>] ? ext4_mb_discard_group_preallocations+0x336/0x400 [ext4] [<f87fb7f1>] ? ext4_mb_new_blocks+0x3d1/0x4f0 [ext4] [<c05a6c5b>] ? __make_request+0x10b/0x440 [<f87f1fb4>] ? ext4_ext_map_blocks+0x1334/0x1980 [ext4] [<c04ac78a>] ? rb_reserve_next_event+0xaa/0x3b0 [<f87d18d6>] ? ext4_map_blocks+0xd6/0x1d0 [ext4] [<f87d2da7>] ? mpage_da_map_blocks+0xc7/0x8a0 [ext4] [<c04c8a68>] ? find_get_pages_tag+0x38/0x110 [<c04d23a5>] ? __pagevec_release+0x15/0x20 [<f87d3ca5>] ? ext4_da_writepages+0x2b5/0x5d0 [ext4] [<c04cfbe0>] ? __writepage+0x0/0x30 [<c04d0e34>] ? do_writepages+0x14/0x30 [<c0526600>] ? writeback_single_inode+0xa0/0x240 [<c0526971>] ? writeback_sb_inodes+0xc1/0x180 [<c0526ab8>] ? writeback_inodes_wb+0x88/0x140 [<c0526d7b>] ? wb_writeback+0x20b/0x320 [<c045aca7>] ? lock_timer_base+0x27/0x50 [<c0526fe0>] ? wb_do_writeback+0x150/0x190 [<c05270a8>] ? bdi_writeback_thread+0x88/0x1f0 [<c043b680>] ? complete+0x40/0x60 [<c0527020>] ? bdi_writeback_thread+0x0/0x1f0 [<c0469474>] ? kthread+0x74/0x80 [<c0469400>] ? kthread+0x0/0x80 [<c040a23e>] ? kernel_thread_helper+0x6/0x10 Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>		2010-10-27 21:27:12 -04:00
..
acpi	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6	2010-09-07 16:00:17 -07:00
asm-generic	gpio: doc updates	2010-09-09 18:57:24 -07:00
crypto
drm	drm: Use a nondestructive mode for output detect when polling (v2)	2010-09-14 20:38:48 +10:00
keys	DNS: Separate out CIFS DNS Resolver code	2010-08-05 17:17:51 +00:00
linux	jbd2: Fix I/O hang in jbd2_journal_release_jbd_inode	2010-10-27 21:25:12 -04:00
math-emu
media	V4L/DVB: cx2341x: convert to the control framework	2010-08-08 23:43:05 -03:00
mtd	mtd: Update copyright notices	2010-08-08 20:58:20 +01:00
net	tproxy: check for transparent flag in ip_route_newports	2010-09-27 15:03:33 -07:00
pcmcia	pcmcia: use struct resource for PCMCIA devices, part 2	2010-08-03 09:04:16 +02:00
rdma	IB: Rename RAW_ETY to RAW_ETHERTYPE	2010-08-04 10:44:19 -07:00
rxrpc
scsi	scsi: use __uX types for headers exported to user space	2010-08-11 08:59:01 -07:00
sound	ALSA: emu10k1 - delay the PCM interrupts (add pcm_irq_delay parameter)	2010-08-18 15:10:59 +02:00
trace	ext4: avoid null dereference in trace_ext4_mballoc_discard	2010-10-27 21:27:12 -04:00
video	include: replace unifdef-y with header-y	2010-08-14 22:26:51 +02:00
xen	xen: pvhvm: make it clearer that XEN_UNPLUG_* define bits in a bitfield	2010-08-23 12:01:35 +01:00
Kbuild