dcbz, dcbf, dcbi, dcbst and icbi do not set DAR when they cause a DTLB Error. Dectect this by tagging DAR with 0x00f0 at every exception exit that modifies DAR. Test for DAR=0x00f0 in DataTLBError and bail to handle_page_fault(). --- arch/powerpc/kernel/head_8xx.S | 15 ++++++++++++++- 1 files changed, 14 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 3bf0603..093176c 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -206,6 +206,8 @@ MachineCheck: EXCEPTION_PROLOG mfspr r4,SPRN_DAR stw r4,_DAR(r11) + li r5,0x00f0 + mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */ mfspr r5,SPRN_DSISR stw r5,_DSISR(r11) addi r3,r1,STACK_FRAME_OVERHEAD @@ -222,6 +224,8 @@ DataAccess: stw r10,_DSISR(r11) mr r5,r10 mfspr r4,SPRN_DAR + li r10,0x00f0 + mtspr SPRN_DAR,r10 /* Tag DAR, to be used in DTLB Error */ EXC_XFER_EE_LITE(0x300, handle_page_fault) /* Instruction access exception. @@ -244,6 +248,8 @@ Alignment: EXCEPTION_PROLOG mfspr r4,SPRN_DAR stw r4,_DAR(r11) + li r5,0x00f0 + mtspr SPRN_DAR,r5 /* Tag DAR, to be used in DTLB Error */ mfspr r5,SPRN_DSISR stw r5,_DSISR(r11) addi r3,r1,STACK_FRAME_OVERHEAD @@ -445,6 +451,7 @@ DataStoreTLBMiss: * of the MMU. */ 2: li r11, 0x00f0 + mtspr SPRN_DAR,r11 /* Tag DAR */ rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */ DO_8xx_CPU6(0x3d80, r3) mtspr SPRN_MD_RPN, r10 /* Update TLB entry */ @@ -485,6 +492,10 @@ DataTLBError: stw r10, 0(r0) stw r11, 4(r0) + mfspr r10, SPRN_DAR + cmpwi cr0, r10, 0x00f0 + beq- 2f /* must be a buggy dcbX, icbi insn. */ + mfspr r11, SPRN_DSISR andis. r11, r11, 0x4800 /* !translation or protection */ bne 2f /* branch if either is set */ @@ -508,7 +519,8 @@ DataTLBError: * are initialized in mapin_ram(). This will avoid the problem, * assuming we only use the dcbi instruction on kernel addresses. */ - mfspr r10, SPRN_DAR + + /* DAR is in r10 already */ rlwinm r11, r10, 0, 0, 19 ori r11, r11, MD_EVALID mfspr r10, SPRN_M_CASID @@ -550,6 +562,7 @@ DataTLBError: * of the MMU. */ li r11, 0x00f0 + mtspr SPRN_DAR,r11 /* Tag DAR */ rlwimi r10, r11, 0, 24, 28 /* Set 24-27, clear 28 */ DO_8xx_CPU6(0x3d80, r3) mtspr SPRN_MD_RPN, r10 /* Update TLB entry */ -- 1.6.4.4 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev