| Message ID | 24702482.jSiYyYTB4u@aspire.rjw.lan (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 07/10/2018 11:56 AM, Rafael J. Wysocki wrote: > On Tuesday, July 10, 2018 5:04:21 PM CEST Jeremy Linton wrote: >> Hi, >> >> On 07/10/2018 06:25 AM, Rafael J. Wysocki wrote: >>> On Tuesday, July 10, 2018 1:13:17 PM CEST Rafael J. Wysocki wrote: >>>> On Tuesday, July 10, 2018 5:44:05 AM CEST Jeremy Linton wrote: >>>>> Hi, >>>>> >>>>> On 07/09/2018 04:28 PM, Rafael J. Wysocki wrote: >>>>>> On Mon, Jul 9, 2018 at 10:45 PM, Jeremy Linton <jeremy.linton@arm.com> wrote: >>>>>>> Hi, >>>>>>> >>>>>>> First thanks for the patch.. >>>>>>> >>>>>>> On 07/08/2018 04:14 AM, Rafael J. Wysocki wrote: >>>>>>>> >>>>>>>> On Monday, July 2, 2018 11:41:42 PM CEST Jeremy Linton wrote: >>>>>>>>> >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> I'm experiencing two problems with commit 5088814a6e931 which is >>>>>>>>> "ACPICA: AML parser: attempt to continue loading table after error" >>>>>>>>> >>>>>>>>> The first is this boot failure on a thunderX2: >>>>>>>>> >>>>>>>>> [ 10.770098] ACPI Error: Ignore error and continue table load >>>>>>> >>>>>>> >>>>>>> [trimming] >>>>>>> >>>>>>>>> ]--- >>>>>>>>> >>>>>>>>> Which does appear to be the result of some bad data in the table, but it >>>>>>>>> was working with 4.17, and reverting this commit solves the problem. >>>>>>>> >>>>>>>> >>>>>>>> Does the patch below make any difference? >>>>>>>> >>>>>>>> --- >>>>>>>> drivers/acpi/acpica/psobject.c | 3 +++ >>>>>>>> 1 file changed, 3 insertions(+) >>>>>>>> >>>>>>>> Index: linux-pm/drivers/acpi/acpica/psobject.c >>>>>>>> =================================================================== >>>>>>>> --- linux-pm.orig/drivers/acpi/acpica/psobject.c >>>>>>>> +++ linux-pm/drivers/acpi/acpica/psobject.c >>>>>>>> @@ -39,6 +39,9 @@ static acpi_status acpi_ps_get_aml_opcod >>>>>>>> ACPI_FUNCTION_TRACE_PTR(ps_get_aml_opcode, walk_state); >>>>>>>> walk_state->aml = walk_state->parser_state.aml; >>>>>>>> + if (!walk_state->aml) >>>>>>>> + return AE_CTRL_PARSE_CONTINUE; >>>>>>>> + >>>>>>> >>>>>>> >>>>>>> Well this seems to avoid the crash, but now it hangs right after on the >>>>>>> "Ignore error and continue table load" message. >>>>>> >>>>>> Well, maybe we should just abort in that case. >>>>>> >>>>>> I'm wondering what happens if you replace the return statement in the >>>>>> patch above with >>>>>> >>>>>> return_ACPI_STATUS(AE_AML_BAD_OPCODE) >>>>> >>>>> Yes, that is where I went when I applied the patch but I used >>>>> AE_CTRL_TERMINATE, which terminates the loop in acpi_ps_parse_loop() and >>>>> that appears to successfully finish/terminate the initial parsing pass. >>>>> But, it then crashes in acpi_ns_lookup called via the >>>>> acpi_walk_resources sequences that goes through ut_evalute_object() due >>>>> to the path/scope_info->scope.node being ACPI_ROOT_OBJECT (-1) and >>>>> bypassing the null check. Adding a ACPI_ROOT_OBJECT check as well as the >>>>> null checks in acpi_ns_lookup results in a successful boot. Tracking >>>>> down how the terminate (or whatever) is leaving the info->prefix_node >>>>> (in acpi_ns_evaluate) set to ROOT_OBJECT instead of null, is something I >>>>> don't yet understand. >>>>> >>>>> Anyway, I tried Using BAD_OPCODE rather than TERMINATE and it seems to >>>>> have the same basic result as PARSE_CONTINUE. >>>> >>>> OK, thanks! >>>> >>>> I evidently didn't look deep enough. >>>> >>>> Can you please check the patch below? >>>> >>>> I'm not sure if we can pass this broken state to >>>> acpi_ps_complete_final_op(), so it may be necessary to return >>>> an error directly when aml_op_start is NULL. >>>> >>>> --- >>>> drivers/acpi/acpica/psloop.c | 3 +++ >>>> 1 file changed, 3 insertions(+) >>>> >>>> Index: linux-pm/drivers/acpi/acpica/psloop.c >>>> =================================================================== >>>> --- linux-pm.orig/drivers/acpi/acpica/psloop.c >>>> +++ linux-pm/drivers/acpi/acpica/psloop.c >>>> @@ -493,6 +493,9 @@ acpi_status acpi_ps_parse_loop(struct ac >>>> ASL_CV_CAPTURE_COMMENTS(walk_state); >>>> >>>> aml_op_start = parser_state->aml; >>>> + if (!aml_op_start) >>>> + break; >>>> + >>>> if (!op) { >>>> status = >>>> acpi_ps_create_op(walk_state, aml_op_start, &op); >>>> >>>> -- >>> >>> So maybe something like this: >>> >>> --- >>> drivers/acpi/acpica/psloop.c | 3 +++ >>> 1 file changed, 3 insertions(+) >>> >>> Index: linux-pm/drivers/acpi/acpica/psloop.c >>> =================================================================== >>> --- linux-pm.orig/drivers/acpi/acpica/psloop.c >>> +++ linux-pm/drivers/acpi/acpica/psloop.c >>> @@ -494,6 +494,9 @@ acpi_status acpi_ps_parse_loop(struct ac >>> >>> aml_op_start = parser_state->aml; >>> if (!op) { >>> + if (!aml_op_start) >>> + return_ACPI_STATUS(AE_AML_INTERNAL); >>> + >>> status = >>> acpi_ps_create_op(walk_state, aml_op_start, &op); >>> if (ACPI_FAILURE(status)) { >>> >>> >> >> This gets rid of the infinite loop, but its still has the problem with >> acpi_ns_lookup crashing due to -1 in the scope.node. > > OK, so do you mean that something like the patch below is needed for the > system to boot? Yes, the machine is back to the pre 4.18 behavior (with the addition of a lot of additional ACPI error messages) boot with those two changes. > --- > drivers/acpi/acpica/nsaccess.c | 3 ++- > drivers/acpi/acpica/psloop.c | 3 +++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > Index: linux-pm/drivers/acpi/acpica/psloop.c > =================================================================== > --- linux-pm.orig/drivers/acpi/acpica/psloop.c > +++ linux-pm/drivers/acpi/acpica/psloop.c > @@ -494,6 +494,9 @@ acpi_status acpi_ps_parse_loop(struct ac > > aml_op_start = parser_state->aml; > if (!op) { > + if (!aml_op_start) > + return_ACPI_STATUS(AE_AML_INTERNAL); > + > status = > acpi_ps_create_op(walk_state, aml_op_start, &op); > if (ACPI_FAILURE(status)) { > Index: linux-pm/drivers/acpi/acpica/nsaccess.c > =================================================================== > --- linux-pm.orig/drivers/acpi/acpica/nsaccess.c > +++ linux-pm/drivers/acpi/acpica/nsaccess.c > @@ -286,7 +286,8 @@ acpi_ns_lookup(union acpi_generic_state > > /* Get the prefix scope. A null scope means use the root scope */ > > - if ((!scope_info) || (!scope_info->scope.node)) { > + if ((!scope_info) || (!scope_info->scope.node) || > + (scope_info->scope.node == ACPI_ROOT_OBJECT)) { > ACPI_DEBUG_PRINT((ACPI_DB_NAMES, > "Null scope prefix, using root node (%p)\n", > acpi_gbl_root_node)); >
Index: linux-pm/drivers/acpi/acpica/psloop.c =================================================================== --- linux-pm.orig/drivers/acpi/acpica/psloop.c +++ linux-pm/drivers/acpi/acpica/psloop.c @@ -494,6 +494,9 @@ acpi_status acpi_ps_parse_loop(struct ac aml_op_start = parser_state->aml; if (!op) { + if (!aml_op_start) + return_ACPI_STATUS(AE_AML_INTERNAL); + status = acpi_ps_create_op(walk_state, aml_op_start, &op); if (ACPI_FAILURE(status)) { Index: linux-pm/drivers/acpi/acpica/nsaccess.c =================================================================== --- linux-pm.orig/drivers/acpi/acpica/nsaccess.c +++ linux-pm/drivers/acpi/acpica/nsaccess.c @@ -286,7 +286,8 @@ acpi_ns_lookup(union acpi_generic_state /* Get the prefix scope. A null scope means use the root scope */ - if ((!scope_info) || (!scope_info->scope.node)) { + if ((!scope_info) || (!scope_info->scope.node) || + (scope_info->scope.node == ACPI_ROOT_OBJECT)) { ACPI_DEBUG_PRINT((ACPI_DB_NAMES, "Null scope prefix, using root node (%p)\n", acpi_gbl_root_node));