diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 059b3a356250..ed8628c6f0f4 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -510,9 +510,9 @@ EXC_REAL_BEGIN(data_access_slb, 0x380, 0x80) SET_SCRATCH0(r13) EXCEPTION_PROLOG_0(PACA_EXSLB) EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x380) - std r3,PACA_EXSLB+EX_R3(r13) + mr r12,r3 /* save r3 */ mfspr r3,SPRN_DAR - mfspr r12,SPRN_SRR1 + mfspr r11,SPRN_SRR1 crset 4*cr6+eq #ifndef CONFIG_RELOCATABLE b slb_miss_realmode @@ -532,9 +532,9 @@ EXC_VIRT_BEGIN(data_access_slb, 0x4380, 0x80) SET_SCRATCH0(r13) EXCEPTION_PROLOG_0(PACA_EXSLB) EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x380) - std r3,PACA_EXSLB+EX_R3(r13) + mr r12,r3 /* save r3 */ mfspr r3,SPRN_DAR - mfspr r12,SPRN_SRR1 + mfspr r11,SPRN_SRR1 crset 4*cr6+eq #ifndef CONFIG_RELOCATABLE b slb_miss_realmode @@ -576,9 +576,9 @@ EXC_REAL_BEGIN(instruction_access_slb, 0x480, 0x80) SET_SCRATCH0(r13) EXCEPTION_PROLOG_0(PACA_EXSLB) EXCEPTION_PROLOG_1(PACA_EXSLB, KVMTEST_PR, 0x480) - std r3,PACA_EXSLB+EX_R3(r13) + mr r12,r3 /* save r3 */ mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */ - mfspr r12,SPRN_SRR1 + mfspr r11,SPRN_SRR1 crclr 4*cr6+eq #ifndef CONFIG_RELOCATABLE b slb_miss_realmode @@ -593,9 +593,9 @@ EXC_VIRT_BEGIN(instruction_access_slb, 0x4480, 0x80) SET_SCRATCH0(r13) EXCEPTION_PROLOG_0(PACA_EXSLB) EXCEPTION_PROLOG_1(PACA_EXSLB, NOTEST, 0x480) - std r3,PACA_EXSLB+EX_R3(r13) + mr r12,r3 /* save r3 */ mfspr r3,SPRN_SRR0 /* SRR0 is faulting address */ - mfspr r12,SPRN_SRR1 + mfspr r11,SPRN_SRR1 crclr 4*cr6+eq #ifndef CONFIG_RELOCATABLE b slb_miss_realmode @@ -612,10 +612,10 @@ TRAMP_KVM(PACA_EXSLB, 0x480) EXC_COMMON_BEGIN(slb_miss_realmode) /* * r13 points to the PACA, r9 contains the saved CR, - * r12 contain the saved SRR1, SRR0 is still ready for return + * r12 contains the saved r3, + * r11 contain the saved SRR1, SRR0 is still ready for return * r3 has the faulting address * r9 - r13 are saved in paca->exslb. - * r3 is saved in paca->slb_r3 * cr6.eq is set for a D-SLB miss, clear for a I-SLB miss * We assume we aren't going to take any exceptions during this * procedure. @@ -624,6 +624,15 @@ EXC_COMMON_BEGIN(slb_miss_realmode) stw r9,PACA_EXSLB+EX_CCR(r13) /* save CR in exc. frame */ std r10,PACA_EXSLB+EX_LR(r13) /* save LR */ + /* + * Test MSR_RI before calling slb_allocate_realmode, because the + * MSR in r11 gets clobbered. However we still want to allocate + * SLB in case MSR_RI=0, to minimise the risk of getting stuck in + * recursive SLB faults. So use cr5 for this, which is preserved. + */ + andi. r11,r11,MSR_RI /* check for unrecoverable exception */ + cmpdi cr5,r11,MSR_RI + crset 4*cr0+eq #ifdef CONFIG_PPC_STD_MMU_64 BEGIN_MMU_FTR_SECTION @@ -637,21 +646,21 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) beq- 8f /* if bad address, make full stack frame */ - andi. r10,r12,MSR_RI /* check for unrecoverable exception */ - beq- 2f + bne- cr5,2f /* if unrecoverable exception, oops */ /* All done -- return from exception. */ .machine push .machine "power4" mtcrf 0x80,r9 + mtcrf 0x04,r9 /* MSR[RI] indication is in cr5 */ mtcrf 0x02,r9 /* I/D indication is in cr6 */ mtcrf 0x01,r9 /* slb_allocate uses cr0 and cr7 */ .machine pop RESTORE_CTR(r9, PACA_EXSLB) RESTORE_PPR_PACA(PACA_EXSLB, r9) - ld r3,PACA_EXSLB+EX_R3(r13) + mr r3,r12 ld r9,PACA_EXSLB+EX_R9(r13) ld r10,PACA_EXSLB+EX_R10(r13) ld r11,PACA_EXSLB+EX_R11(r13) @@ -661,8 +670,9 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) b . /* prevent speculative execution */ 2: std r3,PACA_EXSLB+EX_DAR(r13) - ld r3,PACA_EXSLB+EX_R3(r13) + mr r3,r12 mfspr r11,SPRN_SRR0 + mfspr r12,SPRN_SRR1 LOAD_HANDLER(r10,unrecov_slb) mtspr SPRN_SRR0,r10 ld r10,PACAKMSR(r13) @@ -671,8 +681,9 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_TYPE_RADIX) b . 8: std r3,PACA_EXSLB+EX_DAR(r13) - ld r3,PACA_EXSLB+EX_R3(r13) + mr r3,r12 mfspr r11,SPRN_SRR0 + mfspr r12,SPRN_SRR1 LOAD_HANDLER(r10,bad_addr_slb) mtspr SPRN_SRR0,r10 ld r10,PACAKMSR(r13)