Re: [PATCH 3/7] pc-bios: s390x: Remove unneeded dasd-ipl.c reset psw mask changes

[Thomas Huth]

On 20/07/2020 14.16, Janosch Frank wrote:
> On 7/20/20 1:45 PM, Thomas Huth wrote:
>> On 15/07/2020 11.40, Janosch Frank wrote:
>>> jump_to_low_kernel() and the functions that it calls will already or
>>> 64 bit addressing into the reset psw mask when executing
>>> jump_to_IPL_2() after the diag308 subcode 1.
>>
>> But there is also a check in jump_to_low_kernel that could be affected
>> by your change:
>>
>>     if (*((uint64_t *)0) & RESET_PSW_MASK) {
>>         jump_to_IPL_code((*((uint64_t *)0)) & PSW_MASK_SHORT_ADDR);
>>     }
>>
>> ... but I assume that there should not be any kernels out there in the
>> wild which do not have these bits set, so I think your modifications
>> here should be ok.
> 
> The mask needs to have the short bit indication set so it needs to be !=
> 0 anyway, no?

That's true. If there were still broken images out there, they should
have stopped working since commit 104130cb7c106378da anyway.

 Thomas