For unimplemented instructions or unimplemented SPRs, the 8xx triggers a "Software Emulation Exception" (0x1000). That interrupt doesn't set reason bits in SRR1 as the "Program Check Exception" does.
Go through emulation_assist_interrupt() to set REASON_ILLEGAL. Fixes: fbbcc3bb139e ("powerpc/8xx: Remove SoftwareEmulation()") Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu> --- I'm wondering whether it wouldn't be better to set REASON_ILLEGAL in the exception prolog and still call program_check_exception. And do the same in book3s/64 to avoid the nightmare of an INTERRUPT_HANDLER calling another INTERRUPT_HANDLER. --- arch/powerpc/kernel/head_8xx.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 52702f3db6df..9eb63cf6ac38 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -165,7 +165,7 @@ SystemCall: /* On the MPC8xx, this is a software emulation interrupt. It occurs * for all unimplemented and illegal instructions. */ - EXCEPTION(0x1000, SoftEmu, program_check_exception, EXC_XFER_STD) + EXCEPTION(0x1000, SoftEmu, emulation_assist_interrupt, EXC_XFER_STD) . = 0x1100 /* -- 2.25.0