powerpc/64s: Report SLB multi-hit rather than parity error

When we take an SLB multi-hit on bare metal, we see both the multi-hit
and parity error bits set in DSISR. The user manuals indicates this is
expected to always happen on Power8, whereas on Power9 it says a
multi-hit will "usually" also cause a parity error.

We decide what to do based on the various error tables in mce_power.c,
and because we process them in order and only report the first, we
currently always report a parity error but not the multi-hit, eg:

  Severe Machine check interrupt [Recovered]
    Initiator: CPU
    Error type: SLB [Parity]
      Effective address: c000000ffffd4300

Although this is correct, it leaves the user wondering why they got a
parity error. It would be clearer instead if we reported the
multi-hit because that is more likely to be simply a software bug,
whereas a true parity error is possibly an indication of a bad core.

We can do that simply by reordering the error tables so that multi-hit
appears before parity. That doesn't affect the error recovery at all,
because we flush the SLB either way.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Michael Ellerman 2018-06-13 23:24:14 +10:00
parent e11b64b1ef
commit 54dbcfc211

View File

@ -257,12 +257,12 @@ static const struct mce_derror_table mce_p7_derror_table[] = {
{ 0x00000400, true,
MCE_ERROR_TYPE_TLB, MCE_TLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_INDETERMINATE, /* BOTH */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
@ -290,12 +290,12 @@ static const struct mce_derror_table mce_p8_derror_table[] = {
{ 0x00000200, true,
MCE_ERROR_TYPE_ERAT, MCE_ERAT_ERROR_MULTIHIT, /* SECONDARY ERAT */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0, false, 0, 0, 0, 0 } };
static const struct mce_derror_table mce_p9_derror_table[] = {
@ -320,12 +320,12 @@ static const struct mce_derror_table mce_p9_derror_table[] = {
{ 0x00000200, false,
MCE_ERROR_TYPE_USER, MCE_USER_ERROR_TLBIE,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT, /* Before PARITY */
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000100, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_PARITY,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000080, true,
MCE_ERROR_TYPE_SLB, MCE_SLB_ERROR_MULTIHIT,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },
{ 0x00000040, true,
MCE_ERROR_TYPE_RA, MCE_RA_ERROR_LOAD,
MCE_INITIATOR_CPU, MCE_SEV_ERROR_SYNC, },