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Linux 5.4.199

DISCUSSION Greg Kroah-Hartman 1 participant 2 messages Jun 16, 2022 Stable branch

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Greg Kroah-Hartman

author maintainer
#0 lore raw

I'm announcing the release of the 5.4.199 kernel.

All users of the 5.4 kernel series must upgrade.

The updated 5.4.y git tree can be found at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-5.4.y
and can be browsed at the normal kernel.org git web browser:
https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary

thanks,

greg k-h

------------

 Documentation/ABI/testing/sysfs-devices-system-cpu              |    1 
 Documentation/admin-guide/hw-vuln/index.rst                     |    1 
 Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst |  246 ++++++++++
 Documentation/admin-guide/kernel-parameters.txt                 |   36 +
 Makefile                                                        |    2 
 arch/x86/include/asm/cpufeatures.h                              |    1 
 arch/x86/include/asm/intel-family.h                             |    9 
 arch/x86/include/asm/msr-index.h                                |   25 +
 arch/x86/include/asm/nospec-branch.h                            |    2 
 arch/x86/kernel/cpu/bugs.c                                      |  235 ++++++++-
 arch/x86/kernel/cpu/common.c                                    |   52 +-
 arch/x86/kvm/vmx/vmx.c                                          |   75 +++
 arch/x86/kvm/vmx/vmx.h                                          |    3 
 arch/x86/kvm/x86.c                                              |    4 
 drivers/base/cpu.c                                              |    8 
 include/linux/cpu.h                                             |    4 
 16 files changed, 663 insertions(+), 41 deletions(-)

Gayatri Kammela (1):
x86/cpu: Add another Alder Lake CPU to the Intel family

Greg Kroah-Hartman (1):

      Linux 5.4.199

Guenter Roeck (1):
cpu/speculation: Add prototype for cpu_show_srbds()

Josh Poimboeuf (1):
x86/speculation/mmio: Print SMT warning

Pawan Gupta (10):
Documentation: Add documentation for Processor MMIO Stale Data x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug x86/speculation: Add a common function for MD_CLEAR mitigation update x86/speculation/mmio: Add mitigation for Processor MMIO Stale Data x86/bugs: Group MDS, TAA & Processor MMIO Stale Data mitigations x86/speculation/mmio: Enable CPU Fill buffer clearing on idle x86/speculation/mmio: Add sysfs reporting for Processor MMIO Stale Data x86/speculation/srbds: Update SRBDS mitigation selection x86/speculation/mmio: Reuse SRBDS mitigation for SBDS
KVM: x86/speculation: Disable Fill buffer clear within guests

Tony Luck (1):
x86/cpu: Add Lakefield, Alder Lake and Rocket Lake models to the to Intel CPU family

Zhang Rui (1):
x86/cpu: Add Jasper Lake to Intel family

author maintainer
#1 lore raw
Documentation/ABI/testing/sysfs-devices-system-cpu +1 -0
index c24afa60a30e..726ac2e01b77 100644
@@ -489,6 +489,7 @@ What:		/sys/devices/system/cpu/vulnerabilities
 		/sys/devices/system/cpu/vulnerabilities/srbds
 		/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
 		/sys/devices/system/cpu/vulnerabilities/itlb_multihit
+		/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
 Date:		January 2018
 Contact:	Linux kernel mailing list <[email protected]>
 Description:	Information about CPU vulnerabilities
Documentation/admin-guide/hw-vuln/index.rst +1 -0
index ca4dbdd9016d..2adec1e6520a 100644
@@ -15,3 +15,4 @@ are configurable at compile, boot or run time.
    tsx_async_abort
    multihit.rst
    special-register-buffer-data-sampling.rst
+   processor_mmio_stale_data.rst
Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst new file +246 -0

246 lines not on this page · raw message

Documentation/admin-guide/kernel-parameters.txt +36 -0
index 979423e1b639..cad17c7a311e 100644
@@ -2681,6 +2681,7 @@
 					       kvm.nx_huge_pages=off [X86]
 					       no_entry_flush [PPC]
 					       no_uaccess_flush [PPC]
+					       mmio_stale_data=off [X86]
 
 				Exceptions:
 					       This does not have any effect on
@@ -2702,6 +2703,7 @@
 				Equivalent to: l1tf=flush,nosmt [X86]
 					       mds=full,nosmt [X86]
 					       tsx_async_abort=full,nosmt [X86]
+					       mmio_stale_data=full,nosmt [X86]
 
 	mminit_loglevel=
 			[KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this
@@ -2711,6 +2713,40 @@
 			log everything. Information is printed at KERN_DEBUG
 			so loglevel=8 may also need to be specified.
 
+	mmio_stale_data=
+			[X86,INTEL] Control mitigation for the Processor
+			MMIO Stale Data vulnerabilities.
+
+			Processor MMIO Stale Data is a class of
+			vulnerabilities that may expose data after an MMIO
+			operation. Exposed data could originate or end in
+			the same CPU buffers as affected by MDS and TAA.
+			Therefore, similar to MDS and TAA, the mitigation
+			is to clear the affected CPU buffers.
+
+			This parameter controls the mitigation. The
+			options are:
+
+			full       - Enable mitigation on vulnerable CPUs
+
+			full,nosmt - Enable mitigation and disable SMT on
+				     vulnerable CPUs.
+
+			off        - Unconditionally disable mitigation
+
+			On MDS or TAA affected machines,
+			mmio_stale_data=off can be prevented by an active
+			MDS or TAA mitigation as these vulnerabilities are
+			mitigated with the same mechanism so in order to
+			disable this mitigation, you need to specify
+			mds=off and tsx_async_abort=off too.
+
+			Not specifying this option is equivalent to
+			mmio_stale_data=full.
+
+			For details see:
+			Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst
+
 	module.sig_enforce
 			[KNL] When CONFIG_MODULE_SIG is set, this means that
 			modules without (valid) signatures will fail to load.
Makefile +1 -1
index 1c99e688da21..a8d2f2a1c052 100644
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 VERSION = 5
 PATCHLEVEL = 4
-SUBLEVEL = 198
+SUBLEVEL = 199
 EXTRAVERSION =
 NAME = Kleptomaniac Octopus
 
arch/x86/include/asm/cpufeatures.h +1 -0
index 56eb9a6524e9..8c28a2365a92 100644
@@ -405,5 +405,6 @@
 #define X86_BUG_TAA			X86_BUG(22) /* CPU is affected by TSX Async Abort(TAA) */
 #define X86_BUG_ITLB_MULTIHIT		X86_BUG(23) /* CPU may incur MCE during certain page attribute changes */
 #define X86_BUG_SRBDS			X86_BUG(24) /* CPU may leak RNG bits if not mitigated */
+#define X86_BUG_MMIO_STALE_DATA		X86_BUG(25) /* CPU is affected by Processor MMIO Stale Data vulnerabilities */
 
 #endif /* _ASM_X86_CPUFEATURES_H */
arch/x86/include/asm/intel-family.h +9 -0
index c606c0b70738..5b07573c3bc8 100644
@@ -86,6 +86,14 @@
 #define INTEL_FAM6_COMETLAKE		0xA5
 #define INTEL_FAM6_COMETLAKE_L		0xA6
 
+#define INTEL_FAM6_ROCKETLAKE		0xA7
+
+/* Hybrid Core/Atom Processors */
+
+#define	INTEL_FAM6_LAKEFIELD		0x8A
+#define INTEL_FAM6_ALDERLAKE		0x97
+#define INTEL_FAM6_ALDERLAKE_L		0x9A
+
 /* "Small Core" Processors (Atom) */
 
 #define INTEL_FAM6_ATOM_BONNELL		0x1C /* Diamondville, Pineview */
@@ -111,6 +119,7 @@
 
 #define INTEL_FAM6_ATOM_TREMONT_D	0x86 /* Jacobsville */
 #define INTEL_FAM6_ATOM_TREMONT		0x96 /* Elkhart Lake */
+#define INTEL_FAM6_ATOM_TREMONT_L	0x9C /* Jasper Lake */
 
 /* Xeon Phi */
 
arch/x86/include/asm/msr-index.h +25 -0
index f312b6f6ac48..c56042916a7c 100644
@@ -105,6 +105,30 @@
 						 * Not susceptible to
 						 * TSX Async Abort (TAA) vulnerabilities.
 						 */
+#define ARCH_CAP_SBDR_SSDP_NO		BIT(13)	/*
+						 * Not susceptible to SBDR and SSDP
+						 * variants of Processor MMIO stale data
+						 * vulnerabilities.
+						 */
+#define ARCH_CAP_FBSDP_NO		BIT(14)	/*
+						 * Not susceptible to FBSDP variant of
+						 * Processor MMIO stale data
+						 * vulnerabilities.
+						 */
+#define ARCH_CAP_PSDP_NO		BIT(15)	/*
+						 * Not susceptible to PSDP variant of
+						 * Processor MMIO stale data
+						 * vulnerabilities.
+						 */
+#define ARCH_CAP_FB_CLEAR		BIT(17)	/*
+						 * VERW clears CPU fill buffer
+						 * even on MDS_NO CPUs.
+						 */
+#define ARCH_CAP_FB_CLEAR_CTRL		BIT(18)	/*
+						 * MSR_IA32_MCU_OPT_CTRL[FB_CLEAR_DIS]
+						 * bit available to control VERW
+						 * behavior.
+						 */
 
 #define MSR_IA32_FLUSH_CMD		0x0000010b
 #define L1D_FLUSH			BIT(0)	/*
@@ -122,6 +146,7 @@
 /* SRBDS support */
 #define MSR_IA32_MCU_OPT_CTRL		0x00000123
 #define RNGDS_MITG_DIS			BIT(0)
+#define FB_CLEAR_DIS			BIT(3)	/* CPU Fill buffer clear disable */
 
 #define MSR_IA32_SYSENTER_CS		0x00000174
 #define MSR_IA32_SYSENTER_ESP		0x00000175
arch/x86/include/asm/nospec-branch.h +2 -0
index 956df82bbc2b..ece2b2c6d020 100644
@@ -313,6 +313,8 @@ DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb);
 DECLARE_STATIC_KEY_FALSE(mds_user_clear);
 DECLARE_STATIC_KEY_FALSE(mds_idle_clear);
 
+DECLARE_STATIC_KEY_FALSE(mmio_stale_data_clear);
+
 #include <asm/segment.h>
 
 /**
arch/x86/kernel/cpu/bugs.c +199 -36

334 lines not on this page · raw message

arch/x86/kernel/cpu/common.c +49 -3

85 lines not on this page · raw message

arch/x86/kvm/vmx/vmx.c +74 -1

121 lines not on this page · raw message

arch/x86/kvm/vmx/vmx.h +3 -0
index 55731dd0096f..7a3362ab5986 100644
@@ -280,8 +280,11 @@ struct vcpu_vmx {
 	u64 msr_ia32_feature_control;
 	u64 msr_ia32_feature_control_valid_bits;
 	u64 ept_pointer;
+	u64 msr_ia32_mcu_opt_ctrl;
+	bool disable_fb_clear;
 
 	struct pt_desc pt_desc;
+
 };
 
 enum ept_pointers_status {
arch/x86/kvm/x86.c +4 -0
index 6dd77e426889..d0b297583df8 100644
@@ -1403,6 +1403,10 @@ static u64 kvm_get_arch_capabilities(void)
 
 	/* KVM does not emulate MSR_IA32_TSX_CTRL.  */
 	data &= ~ARCH_CAP_TSX_CTRL_MSR;
+
+	/* Guests don't need to know "Fill buffer clear control" exists */
+	data &= ~ARCH_CAP_FB_CLEAR_CTRL;
+
 	return data;
 }
 
drivers/base/cpu.c +8 -0
index 81ec0a1020d6..9b5edf1dfe9e 100644
@@ -568,6 +568,12 @@ ssize_t __weak cpu_show_srbds(struct device *dev,
 	return sysfs_emit(buf, "Not affected\n");
 }
 
+ssize_t __weak cpu_show_mmio_stale_data(struct device *dev,
+					struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "Not affected\n");
+}
+
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
 static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
 static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
@@ -577,6 +583,7 @@ static DEVICE_ATTR(mds, 0444, cpu_show_mds, NULL);
 static DEVICE_ATTR(tsx_async_abort, 0444, cpu_show_tsx_async_abort, NULL);
 static DEVICE_ATTR(itlb_multihit, 0444, cpu_show_itlb_multihit, NULL);
 static DEVICE_ATTR(srbds, 0444, cpu_show_srbds, NULL);
+static DEVICE_ATTR(mmio_stale_data, 0444, cpu_show_mmio_stale_data, NULL);
 
 static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_meltdown.attr,
@@ -588,6 +595,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_tsx_async_abort.attr,
 	&dev_attr_itlb_multihit.attr,
 	&dev_attr_srbds.attr,
+	&dev_attr_mmio_stale_data.attr,
 	NULL
 };
 
include/linux/cpu.h +4 -0
index 4e9822cb11f3..29a6fa2f518d 100644
@@ -64,6 +64,10 @@ extern ssize_t cpu_show_tsx_async_abort(struct device *dev,
 					char *buf);
 extern ssize_t cpu_show_itlb_multihit(struct device *dev,
 				      struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_mmio_stale_data(struct device *dev,
+					struct device_attribute *attr,
+					char *buf);
 
 extern __printf(4, 5)
 struct device *cpu_device_create(struct device *parent, void *drvdata,