[U-Boot] [PATCH v4 3/3] ARM: OMAP5: redefine arm_setup_identity_mapping

R Sricharan r.sricharan at ti.com
Tue Jan 8 14:05:59 CET 2013


Hi Vincent,

On Tuesday 08 January 2013 05:57 PM, Vincent Stehlé wrote:
> On 01/08/2013 12:14 PM, R Sricharan wrote:
> (..)
>>   We had this problem of speculative aborts in the kernel uncompress code
>>   as well, which maps all of 4GB address space. It was solved by setting
>>   the non-DRAM region as non-executable(XN) and with client permissions
>>   to the domain in the DACR register.
>>
>>   This way speculative prefetches are avoided not only to the page 0,
>>   but also to other read sensitive I/O regions.
>>
>>   I have created a similar patch in u-boot and posted a RFC now.
>>   I was using your first patch [1] and rest from me.
> (..)
>>
>>   Please let me know your take on that.
>
> Hi Sricharan,
>
> Your solution to this issue looks more elegant to me than my unmapping
> page 0 completely.
>    I tested your patches and they work for me on both GP (without
> security) and EMU (with security) OMAP5 ES1.0 devices. I'll keep them,
> thanks :) You can add my 'Tested-by' if you want:
>
  Thanks for the testing and confirming.
  Will add your <Tested-by> in the re post.

Regards,
  Sricharan



More information about the U-Boot mailing list