riscv64 regression

[Heinrich Schuchardt]

On 1/4/23 16:49, Heinrich Schuchardt wrote:
> On 1/4/23 16:34, Alex wrote:
>>
>> Seeing a regression in functionality across multiple devices. I did a
>> bit of bisecting, here's the path:
>>
>> Thu May 5 19:37:22 2022 -0400
>> working: 03b873b4f41010e4f85a72dd59016bb0b123dde1 gcc 11.1.0
>> no build: 03b873b4f41010e4f85a72dd59016bb0b123dde1 gcc 12.2.0
>> unrecognized opcode `csrs sstatus,a5', extension `zicsr' required
>>
>> Wed Oct 12 14:59:51 2022 +0200
>> broke: e67f34f778baabd76f2e0e645a409fed14d2d156 gcc 12.2.0 (fixes zicsr
>> issue)
>>
>> Mon Dec 19 08:45:26 2022 -0500
>> broke: 2243922edca9f56a9d5519b9d6e36f5d7a18434d gcc 12.2.0
>>
>> Mon Jan 2 09:36:13 2023 -0500
>> broke: 582e3c9fb2337c2f49faa73ac86dde25f4d56901 gcc 12.2.0
>>
>>
>>
>> Working boots our EFI loader fine.
>>
>>
>> Broke boots see similar Load Access faults multiple platforms (qemu,
>> unmatched, StarFive):
>>
>>
>> StarFive VisionFive 2:
>>
>> SATP: 0x80000000000fbe03
>> Calling ExitBootServices. So long, EFI!
>> clk u5_dw_i2c_clk_core already disabled
>> clk u5_dw_i2c_clk_apb already disabled
>> Unhandled exception: Load access fault
>> EPC: 00000000fe6dc496 RA: 00000000fe6dc488 TVAL: 0000000000000000
>> EPC: 000000003e98e496 RA: 000000003e98e488 reloc adjusted
>>
>> SP: 00000000ff73b868 GP: 0000000000000000 TP: 0000000000000001
>> T0: 00000000fbf28135 T1: 0000000000000008 T2: 0000000000000000
>> S0: 0000000000000021 S1: 0000000000000000 A0: 0000000000000021
>> A1: 0000000000000000 A2: 0000000000000001 A3: 00000000ff73b968
>> A4: 0000000000000001 A5: 00000000000001ff A6: 0000000000000020
>> A7: 000000000000000a S2: 00000000ff73b968 S3: ffffffc0020940c6
>> S4: 00000000fe713c80 S5: 00000000ff73be94 S6: 00000000ff73beb8
>> S7: 00000000ff73beb0 S8: 00000000ff73bea8 S9: 00000000ff73be98
>> S10: 00000000fe6fc288 S11: 00000000fe713c70 T3: 0000000074757074
>> T4: ffffffffffffffe8 T5: 0000000000000000 T6: 00000000fbf2810d
>>
>> Code: 0b31 0793 1ff0 c763 02a7 842a 5863 00a0 (609c)
>> UEFI image [0x00000000fe6d0000:0x00000000fe720fff] pc=0xc496
>> '/efi\boot\bootriscv64.efi'
>>
>>
>>
>> My questions:
>>
>> * Is GCC 12.2 known broken / unreliable for riscv64 builds of u-boot?
>> * Has anything else changed around memory management on riscv64 between
>> May 2022 and Oct 2022
>>
>> -- Alex
>
> Hello Alex,
>
> I am not aware of a compiler problem.
>
> The crash above occurs in bootriscv64.efi, not in U-Boot.
>
> Analysis would require the code of that binary and instructions how to
> recreate the problem on QEMU.
>
> Best regards
>
> Heinrich
>
>

Analysis of Haiku's efi.map file together with Alex showed that the
problem related to calling Haiku's vprintf() function after
ExitBootServices() which tries to invoke U-Boot's Simple Text Output
Protocol which is illegal after ExitBootServices().

Best regards

Heinrich