From 7df548840c496b0141fb2404b889c346380c2b22 Mon Sep 17 00:00:00 2001 From: Pawan Gupta Date: Wed, 3 Aug 2022 14:41:32 -0700 Subject: x86/bugs: Add "unknown" reporting for MMIO Stale Data Older Intel CPUs that are not in the affected processor list for MMIO Stale Data vulnerabilities currently report "Not affected" in sysfs, which may not be correct. Vulnerability status for these older CPUs is unknown. Add known-not-affected CPUs to the whitelist. Report "unknown" mitigation status for CPUs that are not in blacklist, whitelist and also don't enumerate MSR ARCH_CAPABILITIES bits that reflect hardware immunity to MMIO Stale Data vulnerabilities. Mitigation is not deployed when the status is unknown. [ bp: Massage, fixup. ] Fixes: 8d50cdf8b834 ("x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data") Suggested-by: Andrew Cooper Suggested-by: Tony Luck Signed-off-by: Pawan Gupta Signed-off-by: Borislav Petkov Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/a932c154772f2121794a5f2eded1a11013114711.1657846269.git.pawan.kumar.gupta@linux.intel.com --- .../admin-guide/hw-vuln/processor_mmio_stale_data.rst | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'Documentation') diff --git a/Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst b/Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst index 9393c50b5afc..c98fd11907cc 100644 --- a/Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst +++ b/Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst @@ -230,6 +230,20 @@ The possible values in this file are: * - 'Mitigation: Clear CPU buffers' - The processor is vulnerable and the CPU buffer clearing mitigation is enabled. + * - 'Unknown: No mitigations' + - The processor vulnerability status is unknown because it is + out of Servicing period. Mitigation is not attempted. + +Definitions: +------------ + +Servicing period: The process of providing functional and security updates to +Intel processors or platforms, utilizing the Intel Platform Update (IPU) +process or other similar mechanisms. + +End of Servicing Updates (ESU): ESU is the date at which Intel will no +longer provide Servicing, such as through IPU or other similar update +processes. ESU dates will typically be aligned to end of quarter. If the processor is vulnerable then the following information is appended to the above information: -- cgit v1.2.3-59-g8ed1b From 00da0cb385d05a89226e150a102eb49d8abb0359 Mon Sep 17 00:00:00 2001 From: Salvatore Bonaccorso Date: Mon, 1 Aug 2022 11:15:30 +0200 Subject: Documentation/ABI: Mention retbleed vulnerability info file for sysfs While reporting for the AMD retbleed vulnerability was added in 6b80b59b3555 ("x86/bugs: Report AMD retbleed vulnerability") the new sysfs file was not mentioned so far in the ABI documentation for sysfs-devices-system-cpu. Fix that. Fixes: 6b80b59b3555 ("x86/bugs: Report AMD retbleed vulnerability") Signed-off-by: Salvatore Bonaccorso Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20220801091529.325327-1-carnil@debian.org --- Documentation/ABI/testing/sysfs-devices-system-cpu | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 5bf61881f012..760c889b6cd1 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -523,6 +523,7 @@ What: /sys/devices/system/cpu/vulnerabilities /sys/devices/system/cpu/vulnerabilities/tsx_async_abort /sys/devices/system/cpu/vulnerabilities/itlb_multihit /sys/devices/system/cpu/vulnerabilities/mmio_stale_data + /sys/devices/system/cpu/vulnerabilities/retbleed Date: January 2018 Contact: Linux kernel mailing list Description: Information about CPU vulnerabilities -- cgit v1.2.3-59-g8ed1b