Re: [PATCH 3/9] arm64: mm: install SError abort handler

Florian Fainelli
2017-03-24T17:54:28Z

On 03/24/2017 10:35 AM, Mark Rutland wrote:
> On Fri, Mar 24, 2017 at 09:48:40AM -0700, Doug Berger wrote:
>> On 03/24/2017 08:16 AM, Mark Rutland wrote:
>>> On Fri, Mar 24, 2017 at 07:46:26AM -0700, Doug Berger wrote:
>
>> If you would consider an alternative implementation where we scrap
>> the SError handler (i.e. maintain the ugliness in our downstream
>> kernel) in favor of a more gentle user mode crash on SError that
>> allows the kernel the opportunity to service the interrupt for
>> diagnostic purposes I could try to repackage that.
>
> If this is just for diagnostic purposes, I believe you can register a
> panic notifier, which can then read from the bus. The panic will occur,
> but you'll have the opportunity to log some information to dmesg.

And crash the kernel? That sounds awful, FWIW the ARM/Linux kernel is
able to recover just fine from user-space accessing e.g: invalid
physical addresses in the GISB register space, bringing the same level
of functionality to ARM64/Linux sounds reasonable to me.
--
Florian