ACPICA: Hardware: Do not flush CPU cache when entering S4 and S5
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Wed, 22 Dec 2021 16:33:51 +0000 (17:33 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 27 Jan 2022 10:04:50 +0000 (11:04 +0100)
commitdcedcbe177397122582e9e09b2ada9fdf9596409
treea66701e2ef8ef2e13e348c1ab03a63bc630e2ff4
parenta4c7a12027f2fc4dc6346a24fd3ab829e97955a3
ACPICA: Hardware: Do not flush CPU cache when entering S4 and S5

[ Upstream commit 1d4e0b3abb168b2ee1eca99c527cffa1b80b6161 ]

ACPICA commit 3dd7e1f3996456ef81bfe14cba29860e8d42949e

According to ACPI 6.4, Section 16.2, the CPU cache flushing is
required on entering to S1, S2, and S3, but the ACPICA code
flushes the CPU cache regardless of the sleep state.

Blind cache flush on entering S5 causes problems for TDX.

Flushing happens with WBINVD that is not supported in the TDX
environment.

TDX only supports S5 and adjusting ACPICA code to conform to the
spec more strictly fixes the issue.

Link: https://github.com/acpica/acpica/commit/3dd7e1f3
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/acpi/acpica/hwesleep.c
drivers/acpi/acpica/hwsleep.c
drivers/acpi/acpica/hwxfsleep.c