Merge tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RAS updates from Borislav Petkov:

 - More noinstr fixes

 - Add an erratum workaround for Intel CPUs which, in certain
   circumstances, end up consuming an unrelated uncorrectable memory
   error when using fast string copy insns

 - Remove the MCE tolerance level control as it is not really needed or
   used anymore

* tag 'ras_core_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Remove the tolerance level control
  x86/mce: Work around an erratum on fast string copy instructions
  x86/mce: Use arch atomic and bit helpers

4 files changed, 38 insertions, 42 deletions

diff --git a/Documentation/ABI/removed/sysfs-mce b/Documentation/ABI/removed/sysfs-mce
new file mode 100644
index 000000000000..ef5dd2a80918
--- /dev/null
+++ b/Documentation/ABI/removed/sysfs-mce
@@ -0,0 +1,37 @@
+What:		/sys/devices/system/machinecheck/machinecheckX/tolerant
+Contact:	Borislav Petkov <bp@suse.de>
+Date:		Dec, 2021
+Description:
+		Unused and obsolete after the advent of recoverable machine
+		checks (see last sentence below) and those are present since
+		2010 (Nehalem).
+
+		Original description:
+
+		The entries appear for each CPU, but they are truly shared
+		between all CPUs.
+
+		Tolerance level. When a machine check exception occurs for a
+		non corrected machine check the kernel can take different
+		actions.
+
+		Since machine check exceptions can happen any time it is
+		sometimes risky for the kernel to kill a process because it
+		defies normal kernel locking rules. The tolerance level
+		configures how hard the kernel tries to recover even at some
+		risk of	deadlock. Higher tolerant values trade potentially
+		better uptime with the risk of a crash or even corruption
+		(for tolerant >= 3).
+
+		==  ===========================================================
+		 0  always panic on uncorrected errors, log corrected errors
+		 1  panic or SIGBUS on uncorrected errors, log corrected errors
+		 2  SIGBUS or log uncorrected errors, log corrected errors
+		 3  never panic or SIGBUS, log all errors (for testing only)
+		==  ===========================================================
+
+		Default: 1
+
+		Note this only makes a difference if the CPU allows recovery
+		from a machine check exception. Current x86 CPUs generally
+		do not.
diff --git a/Documentation/ABI/testing/sysfs-mce b/Documentation/ABI/testing/sysfs-mce
index c8cd989034b4..83172f50e27c 100644
--- a/Documentation/ABI/testing/sysfs-mce
+++ b/Documentation/ABI/testing/sysfs-mce
@@ -53,38 +53,6 @@ Description:
 		(but some corrected errors might be still reported
 		in other ways)
 
-What:		/sys/devices/system/machinecheck/machinecheckX/tolerant
-Contact:	Andi Kleen <ak@linux.intel.com>
-Date:		Feb, 2007
-Description:
-		The entries appear for each CPU, but they are truly shared
-		between all CPUs.
-
-		Tolerance level. When a machine check exception occurs for a
-		non corrected machine check the kernel can take different
-		actions.
-
-		Since machine check exceptions can happen any time it is
-		sometimes risky for the kernel to kill a process because it
-		defies normal kernel locking rules. The tolerance level
-		configures how hard the kernel tries to recover even at some
-		risk of	deadlock. Higher tolerant values trade potentially
-		better uptime with the risk of a crash or even corruption
-		(for tolerant >= 3).
-
-		==  ===========================================================
-		 0  always panic on uncorrected errors, log corrected errors
-		 1  panic or SIGBUS on uncorrected errors, log corrected errors
-		 2  SIGBUS or log uncorrected errors, log corrected errors
-		 3  never panic or SIGBUS, log all errors (for testing only)
-		==  ===========================================================
-
-		Default: 1
-
-		Note this only makes a difference if the CPU allows recovery
-		from a machine check exception. Current x86 CPUs generally
-		do not.
-
 What:		/sys/devices/system/machinecheck/machinecheckX/trigger
 Contact:	Andi Kleen <ak@linux.intel.com>
 Date:		Feb, 2007
diff --git a/Documentation/vm/hwpoison.rst b/Documentation/vm/hwpoison.rst
index 89b5f7a52077..c742de1769d1 100644
--- a/Documentation/vm/hwpoison.rst
+++ b/Documentation/vm/hwpoison.rst
@@ -60,8 +60,6 @@ There are two (actually three) modes memory failure recovery can be in:
 
 vm.memory_failure_recovery sysctl set to zero:
 	All memory failures cause a panic. Do not attempt recovery.
-	(on x86 this can be also affected by the tolerant level of the
-	MCE subsystem)
 
 early kill
 	(can be controlled globally and per process)
diff --git a/Documentation/x86/x86_64/boot-options.rst b/Documentation/x86/x86_64/boot-options.rst
index ccb7e86bf8d9..07aa0007f346 100644
--- a/Documentation/x86/x86_64/boot-options.rst
+++ b/Documentation/x86/x86_64/boot-options.rst
@@ -47,14 +47,7 @@ Please see Documentation/x86/x86_64/machinecheck.rst for sysfs runtime tunables.
 		in a reboot. On Intel systems it is enabled by default.
    mce=nobootlog
 		Disable boot machine check logging.
-   mce=tolerancelevel[,monarchtimeout] (number,number)
-		tolerance levels:
-		0: always panic on uncorrected errors, log corrected errors
-		1: panic or SIGBUS on uncorrected errors, log corrected errors
-		2: SIGBUS or log uncorrected errors, log corrected errors
-		3: never panic or SIGBUS, log all errors (for testing only)
-		Default is 1
-		Can be also set using sysfs which is preferable.
+   mce=monarchtimeout (number)
 		monarchtimeout:
 		Sets the time in us to wait for other CPUs on machine checks. 0
 		to disable.