diff options
| author | Mark Kettenis <kettenis@cvs.openbsd.org> | 2014-07-20 12:20:39 +0000 |
|---|---|---|
| committer | Mark Kettenis <kettenis@cvs.openbsd.org> | 2014-07-20 12:20:39 +0000 |
| commit | acda3aecbe922cd831d3c026c738efbc29b46f5e (patch) | |
| tree | da22eaf5ded8e3eb0aa49f9c002f9e6227c6f3d2 /sys/dev/acpi/dsdt.c | |
| parent | 44c89de53c99f01730b08447333749e202894ba7 (diff) | |
Skip reading bits from a region marked as "Preserve" if all bits will be
modified. Some Sony and Asus laptops don't like this; the read seems to
trigger an unwanted SMI that makes the machine hang. Diagnosed by mpi@
ok mpi@
Diffstat (limited to 'sys/dev/acpi/dsdt.c')
| -rw-r--r-- | sys/dev/acpi/dsdt.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/sys/dev/acpi/dsdt.c b/sys/dev/acpi/dsdt.c index 89179f9fae6..20dd8af22d7 100644 --- a/sys/dev/acpi/dsdt.c +++ b/sys/dev/acpi/dsdt.c @@ -1,4 +1,4 @@ -/* $OpenBSD: dsdt.c,v 1.212 2014/07/12 18:48:17 tedu Exp $ */ +/* $OpenBSD: dsdt.c,v 1.213 2014/07/20 12:20:38 kettenis Exp $ */ /* * Copyright (c) 2005 Jordan Hargrave <jordan@openbsd.org> * @@ -2311,7 +2311,8 @@ aml_rwgas(struct aml_value *rgn, int bpos, int blen, struct aml_value *val, aml_bufcpy(vbit, 0, tbit, bpos, blen); } else { /* Write bits to opregion */ - if (AML_FIELD_UPDATE(flag) == AML_FIELD_PRESERVE) { + if (AML_FIELD_UPDATE(flag) == AML_FIELD_PRESERVE && + (bpos != 0 || blen != tlen)) { acpi_gasio(acpi_softc, ACPI_IOREAD, type, pi.addr, sz, tlen >> 3, tbit); } else if (AML_FIELD_UPDATE(flag) == AML_FIELD_WRITEASONES) { |