From a8a013d9f8b70420b56ad211fdbd6c106b870424 Mon Sep 17 00:00:00 2001 From: Radim Krcmar Date: Tue, 23 Jun 2015 15:00:46 +0200 Subject: [PATCH 037/217] pc: acpi: fix pvpanic for buggy guests MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Message-id: <1435071646-9165-1-git-send-email-rkrcmar@redhat.com> Patchwork-id: 66365 O-Subject: [RHEL7.2 qemu-kvm-rhev PATCH] pc: acpi: fix pvpanic for buggy guests Bugzilla: 1221943 RH-Acked-by: Michael S. Tsirkin RH-Acked-by: Paolo Bonzini RH-Acked-by: Igor Mammedov In the old times, we always had pvpanic in ACPI and a _STA method told the guest not to use it. Automatic generation dropped the _STA method as the specification says that missing _STA means enabled and working. Some guests (Linux) had buggy drivers and this change made them unable to utilize pvpanic. A Linux patch is posted as well, but I think it's worth to make pvpanic useable on old guests at the price of three lines and few bytes of SSDT. The old _STA method was Method (_STA, 0, NotSerialized) { Store (PEST, Local0) If (LEqual (Local0, Zero)) { Return (Zero) } Else { Return (0x0F) }} Igor pointed out that we don't need to use a method to return a constant and that 0xB (don't show in UI) is the common definition now. Also, the device used to be PEVT. (PEVT as in "panic event"?) Signed-off-by: Radim Krčmář Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin (cherry picked from commit 2332333c9738b442fbbd5b83a1eaa6be656ab9b5) Signed-off-by: Miroslav Rezanina --- hw/i386/acpi-build.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index 8773e8f..d7f0a4e 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -787,7 +787,7 @@ build_ssdt(GArray *table_data, GArray *linker, if (misc->pvpanic_port) { scope = aml_scope("\\_SB.PCI0.ISA"); - dev = aml_device("PEVR"); + dev = aml_device("PEVT"); aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0001"))); crs = aml_resource_template(); @@ -802,6 +802,9 @@ build_ssdt(GArray *table_data, GArray *linker, aml_append(field, aml_named_field("PEPT", 8)); aml_append(dev, field); + /* device present, functioning, decoding, not shown in UI */ + aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); + method = aml_method("RDPT", 0); aml_append(method, aml_store(aml_name("PEPT"), aml_local(0))); aml_append(method, aml_return(aml_local(0))); -- 1.8.3.1