Re: [PATCH] Re: More than 2Gb problem (dvb related) ?

From: Gregoire Favre
Date: Mon Apr 30 2007 - 12:52:55 EST

On Sat, Apr 28, 2007 at 09:14:37PM +0100, Jon Burgess wrote:

> While the above patch works, it seems the underlying causes is that
> vmalloc_32() is providing memory above 4Gb on x86-64 which is not what
> the driver expects. This same issue came up a few weeks ago with regards
> to DRM on radeon
> Andi Kleen included a patch to ensure vmalloc_32() returns memory <4Gb
> in a patch which is currently in -mm
> With this patch applied the current driver appears to work OK.
> Attached is a smaller patch against v4l-dvb which just adds the missing
> pci_unmap_sg() call.

I was using with the x86_64-mm-vmalloc-32.patch and you small
patch : working but not perftctly stable.

So I compiled 2.6.21-rc7-mm2 and at boot I got a problem :

ksymoops dmesg-2.6.21-rc7-mm2-4Gb.txt
ksymoops 2.4.11 on x86_64 2.6.21-rc7-mm2. Options used
-V (default)
-k /proc/ksyms (default)
-l /proc/modules (default)
-o /lib/modules/2.6.21-rc7-mm2/ (default)
-m /usr/src/linux/ (default)

Warning: You did not tell me where to find symbol information. I will
assume that the log matches the kernel and modules that are running
right now and I'll use the default options above for symbol resolution.
If the current kernel and/or modules do not match the log, you can get
more accurate output by telling me the kernel version and where to find
map, modules, ksyms etc. ksymoops -h explains the options.

Error (regular_file): read_ksyms stat /proc/ksyms failed
ksymoops: No such file or directory
No modules in ksyms, skipping objects
No ksyms, skipping lsmod
SGI XFS with large block/inode numbers, no debug enabled
ehci_hcd 0000:00:1a.7: debug port 1
ehci_hcd 0000:00:1d.7: debug port 1
kernel BUG at mm/slab.c:2766!
Pid: 6616, comm: cx88[0] dvb Tainted: P 2.6.21-rc7-mm2 #1
RIP: 0010:[<ffffffff802608e5>] [<ffffffff802608e5>] cache_alloc_refill+0x495/0x560
Using defaults from ksymoops -t elf64-x86-64 -a i386:x86-64
RSP: 0000:ffff8101045dfd50 EFLAGS: 00010002
RAX: 0000000000000000 RBX: 000000000000003c RCX: 0000000000000000
RDX: ffff81010006a400 RSI: 0000000000000004 RDI: ffff81010001c180
RBP: ffff81010006a400 R08: 00000000ffffffff R09: 0000000000000004
R10: 0000000000000020 R11: 0000000000000001 R12: ffff81010001e2c0
R13: ffff81010001c140 R14: 0000000000000000 R15: ffff81010000b000
FS: 0000000000000000(0000) GS:ffff810100027540(0000) knlGS:0000000000000000
CS: 0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 00002aaab0a9ea18 CR3: 0000000000201000 CR4: 00000000000006e0
Stack: 0000000000021024 0000000000000000 ffff81010001c180 ffff810100054060
ffffc20000000004 0000000000000286 0000000000000030 ffff810102b83140
0000000000006000 0000000000000004 ffff81010241c0e0 ffffffff802c95b8
Call Trace:
[<ffffffff802c95b8>] __kmalloc+0x68/0x70
[<ffffffff802c19e7>] __vmalloc_area_node+0x157/0x1a0
[<ffffffff880bc8a0>] :video_buf:videobuf_dma_init_kernel+0x50/0xd0
[<ffffffff880bcdbe>] :video_buf:videobuf_iolock+0xbe/0xf0
[<ffffffff880fc07e>] :cx8802:cx8802_buf_prepare+0xde/0x130
[<ffffffff880bc0c7>] :video_buf:videobuf_read_start+0xc7/0x170
[<ffffffff880c23b0>] :video_buf_dvb:videobuf_dvb_thread+0x0/0x190
[<ffffffff880c23e9>] :video_buf_dvb:videobuf_dvb_thread+0x39/0x190
[<ffffffff880c23b0>] :video_buf_dvb:videobuf_dvb_thread+0x0/0x190
[<ffffffff802342eb>] kthread+0x4b/0x80
[<ffffffff802622a8>] child_rip+0xa/0x12
[<ffffffff802342a0>] kthread+0x0/0x80
[<ffffffff8026229e>] child_rip+0x0/0x12
Code: 0f 0b eb fe 0f 0b eb fe 41 8b 44 24 30 a8 01 0f 84 ed fd ff

>>RIP; ffffffff802608e5 <cache_alloc_refill+495/560> <=====

>>RDX; ffff81010006a400 <phys_startup_64+ffff8100ffe6a400/ffffffff80000000>
>>RDI; ffff81010001c180 <phys_startup_64+ffff8100ffe1c180/ffffffff80000000>
>>RBP; ffff81010006a400 <phys_startup_64+ffff8100ffe6a400/ffffffff80000000>
>>R08; 00000000ffffffff <phys_startup_64+ffdfffff/ffffffff80000000>
>>R12; ffff81010001e2c0 <phys_startup_64+ffff8100ffe1e2c0/ffffffff80000000>
>>R13; ffff81010001c140 <phys_startup_64+ffff8100ffe1c140/ffffffff80000000>
>>R15; ffff81010000b000 <phys_startup_64+ffff8100ffe0b000/ffffffff80000000>

Trace; ffffffff802c95b8 <__kmalloc+68/70>
Trace; ffffffff802c19e7 <__vmalloc_area_node+157/1a0>
Trace; ffffffff880bc8a0 <_end+79f1b1c/7ef3527c>
Trace; ffffffff880bcdbe <_end+79f203a/7ef3527c>
Trace; ffffffff880fc07e <_end+7a312fa/7ef3527c>
Trace; ffffffff880bc0c7 <_end+79f1343/7ef3527c>
Trace; ffffffff880c23b0 <_end+79f762c/7ef3527c>
Trace; ffffffff880c23e9 <_end+79f7665/7ef3527c>
Trace; ffffffff880c23b0 <_end+79f762c/7ef3527c>
Trace; ffffffff802342eb <kthread+4b/80>
Trace; ffffffff802622a8 <child_rip+a/12>
Trace; ffffffff802342a0 <kthread+0/80>
Trace; ffffffff8026229e <child_rip+0/12>

Code; ffffffff802608e5 <cache_alloc_refill+495/560>
0000000000000000 <_RIP>:
Code; ffffffff802608e5 <cache_alloc_refill+495/560> <=====
0: 0f 0b ud2a <=====
Code; ffffffff802608e7 <cache_alloc_refill+497/560>
2: eb fe jmp 2 <_RIP+0x2>
Code; ffffffff802608e9 <cache_alloc_refill+499/560>
4: 0f 0b ud2a
Code; ffffffff802608eb <cache_alloc_refill+49b/560>
6: eb fe jmp 6 <_RIP+0x6>
Code; ffffffff802608ed <cache_alloc_refill+49d/560>
8: 41 8b 44 24 30 mov 0x30(%r12),%eax
Code; ffffffff802608f2 <cache_alloc_refill+4a2/560>
d: a8 01 test $0x1,%al
Code; ffffffff802608f4 <cache_alloc_refill+4a4/560>
f: 0f 84 ed fd ff 00 je fffe02 <_RIP+0xfffe02>

1 warning and 1 error issued. Results may not be reliable.

I can't compil hg source with your patch for this kernel :

make -C /lib/modules/2.6.21-rc7-mm2/build SUBDIRS=/usr/src/CVS/v4l-dvb/v4l modules
make[1]: Entering directory `/usr/src/linux-2.6.21-rc7-mm2'
CC [M] /usr/src/CVS/v4l-dvb/v4l/dvb_net.o
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c: In function 'dvb_net_eth_type_trans':
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c:186: error: 'struct sk_buff' has no member named 'mac'
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c: In function 'dvb_net_ule':
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c:625: warning: cast to pointer from integer of different size
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c:626: warning: cast to pointer from integer of different size
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c:627: warning: cast to pointer from integer of different size
/usr/src/CVS/v4l-dvb/v4l/dvb_net.c:628: warning: cast to pointer from integer of different size
make[2]: *** [/usr/src/CVS/v4l-dvb/v4l/dvb_net.o] Error 1
make[1]: *** [_module_/usr/src/CVS/v4l-dvb/v4l] Error 2
make[1]: Leaving directory `/usr/src/linux-2.6.21-rc7-mm2'
make: *** [default] Error 2

What kernel (with which patches) are you using ?

Grégoire FAVRE
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