Re: [Qustion] vmalloc area overlap with another allocated vmalloc area

From: zhong jiang
Date: Wed May 17 2017 - 09:03:35 EST


+to linux-mm maintainer for any suggestions

Thanks
zhongjiang
On 2017/5/16 13:03, zhong jiang wrote:
> Hi
>
> I hit the following issue by runing /proc/vmallocinfo. The kernel is 4.1 stable and
> 32 bit to be used. after I expand the vamlloc area, the issue is not occur again.
> it is related to the overflow. but I do not see any problem so far.
>
> cat /proc/vmallocinfo
> 0xf1580000-0xf1600000 524288 raw_dump_mem_write+0x10c/0x188 phys=8b901000 ioremap
> 0xf1638000-0xf163a000 8192 mcss_pou_queue_init+0xa0/0x13c [mcss] phys=fc614000 ioremap
> 0xf528e000-0xf5292000 16384 n_tty_open+0x10/0xd0 pages=3 vmalloc
> 0xf5000000-0xf9001000 67112960 devm_ioremap+0x38/0x70 phys=40000000 ioremap
> 0xfe001000-0xfe002000 4096 iotable_init+0x0/0xc phys=20001000 ioremap
> 0xfe200000-0xfe201000 4096 iotable_init+0x0/0xc phys=1a000000 ioremap
> 0xff100000-0xff101000 4096 iotable_init+0x0/0xc phys=2000a000 ioremap
>
> n_tty_open allocate the vmap area is surrounded by the devm_ioremap ioremap by above info.
> I do not see also the race in the condition.
>
> I have no idea to the issue. Anyone has any suggestions will be appreicated.
> The related config is attatched.
>
> Thanks
> zhongjiang