riscv64 regression

[Heinrich Schuchardt]

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