Hi, During SVN checkout (means heavy I/O), I hit this kernel BUG with current linus git (637704cb : Merge branch 'i2c-embedded/for-next'), in my VMWare Linux guest.
[ 9141.015123] BUG: unable to handle kernel NULL pointer dereference at 00000280 [ 9141.017870] IP: [<c04ba69c>] wait_iff_congested+0x45/0xdd [ 9141.034799] *pde = 00000000 [ 9141.034803] Oops: 0000 [#1] SMP [ 9141.044282] Modules linked in: vmwgfx ttm drm [ 9141.044331] Pid: 42, comm: kswapd0 Not tainted 3.8.0-rc1+ #120 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform [ 9141.044334] EIP: 0060:[<c04ba69c>] EFLAGS: 00010202 CPU: 3 [ 9141.044342] EIP is at wait_iff_congested+0x45/0xdd [ 9141.044343] EAX: 00000001 EBX: 00000000 ECX: 00000000 EDX: 00000000 [ 9141.044345] ESI: 0000001e EDI: f633fec0 EBP: f633fecc ESP: f633fea8 [ 9141.044347] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 [ 9141.044348] CR0: 8005003b CR2: 00000280 CR3: 33ab7000 CR4: 000007d0 [ 9141.045817] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 9141.045834] DR6: ffff0ff0 DR7: 00000400 [ 9141.045836] Process kswapd0 (pid: 42, ti=f633e000 task=f6331920 task.ti=f633e000) [ 9141.045838] Stack: [ 9141.045839] 002889e6 00000000 f6331920 c04462a2 f633feb8 f633feb8 c0beba54 c0bead00 [ 9141.045844] 00000003 f633ff68 c04b3ffb 00000002 00000000 000086d1 f6331920 f633ff58 [ 9141.045849] 00000000 f6331920 00037b92 00000000 00000045 00000000 00000038 00000001 [ 9141.045854] Call Trace: [ 9141.045934] [<c04462a2>] ? remove_wait_queue+0x27/0x27 [ 9141.045939] [<c04b3ffb>] kswapd+0x5ef/0x705 [ 9141.045942] [<c04462a2>] ? remove_wait_queue+0x27/0x27 [ 9141.045945] [<c0445cbc>] kthread+0x6b/0x70 [ 9141.045947] [<c04b3a0c>] ? shrink_lruvec+0x492/0x492 [ 9141.083149] [<c0907637>] ret_from_kernel_thread+0x1b/0x28 [ 9141.083166] [<c0445c51>] ? kthread_freezable_should_stop+0x36/0x36 [ 9141.083169] Code: 89 45 dc 31 c0 f3 ab 64 a1 58 66 c7 c0 89 45 e4 8d 45 ec 89 45 ec 89 45 f0 8b 04 95 24 2b cf c0 c7 45 e8 a2 62 44 c0 85 c0 74 0a <8b> 83 80 02 00 00 a8 04 75 1b e8 e9 6f 44 00 a1 40 9a b8 c0 8b [ 9141.089753] EIP: [<c04ba69c>] wait_iff_congested+0x45/0xdd SS:ESP 0068:f633fea8 [ 9141.089764] CR2: 0000000000000280 [ 9141.090296] ---[ end trace 58a34900f079b57e ]---