RE: [GIT PULL] ACPI fix for v4.18-rc7

From: Oleksandr Natalenko
Date: Sat Jul 28 2018 - 12:59:45 EST


Hi.

From a828a091828599154d8f6e8bfee1495a3df5cf34 Mon Sep 17 00:00:00 2001
From: Erik Schmauss <erik.schmauss@xxxxxxxxx>
Date: Fri, 27 Jul 2018 15:37:35 -0700
From: Erik Schmauss <erik.schmauss@xxxxxxxxx>
Subject: [PATCH 1] ACPICA: AML Parser: ignore control method status in module-level code

Previous change in the AML parser code blindly set all non-successful
dispatcher statuses to AE_OK. This approach is incorrect because
successful control method invocations from module-level return
AE_CTRL_TRANSFER. Overwriting AE_OK to this status causes the AML
parser to think that there was no return value from the control
method invocation.

fixes: 73c2a01c52b6 (ACPICA: AML Parser: ignore dispatcher error status during table load)

Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Erik Schmauss <erik.schmauss@xxxxxxxxx>
---
psloop.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)

diff -Nurp linux.before_name/drivers/acpi/acpica/psloop.c linux.after_name/drivers/acpi/acpica/psloop.c
--- linux.before_name/drivers/acpi/acpica/psloop.c 2018-07-27 15:53:31.073522915 -0700
+++ linux.after_name/drivers/acpi/acpica/psloop.c 2018-07-27 15:53:25.320522527 -0700
@@ -714,15 +714,20 @@ acpi_status acpi_ps_parse_loop(struct ac
} else
if ((walk_state->
parse_flags & ACPI_PARSE_MODULE_LEVEL)
+ && status != AE_CTRL_TRANSFER
&& ACPI_FAILURE(status)) {
/*
- * ACPI_PARSE_MODULE_LEVEL means that we are loading a table by
- * executing it as a control method. However, if we encounter
- * an error while loading the table, we need to keep trying to
- * load the table rather than aborting the table load. Set the
- * status to AE_OK to proceed with the table load. If we get a
- * failure at this point, it means that the dispatcher got an
- * error while processing Op (most likely an AML operand error.
+ * ACPI_PARSE_MODULE_LEVEL flag means that we are currently
+ * loading a table by executing it as a control method.
+ * However, if we encounter an error while loading the table,
+ * we need to keep trying to load the table rather than
+ * aborting the table load (setting the status to AE_OK
+ * continues the table load). If we get a failure at this
+ * point, it means that the dispatcher got an error while
+ * processing Op (most likely an AML operand error) or a
+ * control method was called from module level and the
+ * dispatcher returned AE_CTRL_TRANSFER. In the latter case,
+ * leave the status alone, there's nothing wrong with it.
*/
status = AE_OK;
}

Faced the same on my Dell Vostro 3360 with v4.17.11 update, and confirming that this patch fixes the issue for me too.

Thus,

Tested-by: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>

Also, please Cc Greg once you do a submission, so v4.17 stable branch will be fixed too.

Thanks.

--
Oleksandr Natalenko (post-factum)