Re: Linux 5.7.2

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 2e0e3b45d02a..b39531a3c5bc 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -492,6 +492,7 @@ What:		/sys/devices/system/cpu/vulnerabilities
 		/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
 		/sys/devices/system/cpu/vulnerabilities/l1tf
 		/sys/devices/system/cpu/vulnerabilities/mds
+		/sys/devices/system/cpu/vulnerabilities/srbds
 		/sys/devices/system/cpu/vulnerabilities/tsx_async_abort
 		/sys/devices/system/cpu/vulnerabilities/itlb_multihit
 Date:		January 2018
diff --git a/Documentation/admin-guide/hw-vuln/index.rst b/Documentation/admin-guide/hw-vuln/index.rst
index 0795e3c2643f..ca4dbdd9016d 100644
--- a/Documentation/admin-guide/hw-vuln/index.rst
+++ b/Documentation/admin-guide/hw-vuln/index.rst
@@ -14,3 +14,4 @@ are configurable at compile, boot or run time.
    mds
    tsx_async_abort
    multihit.rst
+   special-register-buffer-data-sampling.rst
diff --git a/Documentation/admin-guide/hw-vuln/special-register-buffer-data-sampling.rst b/Documentation/admin-guide/hw-vuln/special-register-buffer-data-sampling.rst
new file mode 100644
index 000000000000..47b1b3afac99
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/special-register-buffer-data-sampling.rst
@@ -0,0 +1,149 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+SRBDS - Special Register Buffer Data Sampling
+=============================================
+
+SRBDS is a hardware vulnerability that allows MDS :doc:`mds` techniques to
+infer values returned from special register accesses.  Special register
+accesses are accesses to off core registers.  According to Intel's evaluation,
+the special register reads that have a security expectation of privacy are
+RDRAND, RDSEED and SGX EGETKEY.
+
+When RDRAND, RDSEED and EGETKEY instructions are used, the data is moved
+to the core through the special register mechanism that is susceptible
+to MDS attacks.
+
+Affected processors
+--------------------
+Core models (desktop, mobile, Xeon-E3) that implement RDRAND and/or RDSEED may
+be affected.
+
+A processor is affected by SRBDS if its Family_Model and stepping is
+in the following list, with the exception of the listed processors
+exporting MDS_NO while Intel TSX is available yet not enabled. The
+latter class of processors are only affected when Intel TSX is enabled
+by software using TSX_CTRL_MSR otherwise they are not affected.
+
+  =============  ============  ========
+  common name    Family_Model  Stepping
+  =============  ============  ========
+  IvyBridge      06_3AH        All
+
+  Haswell        06_3CH        All
+  Haswell_L      06_45H        All
+  Haswell_G      06_46H        All
+
+  Broadwell_G    06_47H        All
+  Broadwell      06_3DH        All
+
+  Skylake_L      06_4EH        All
+  Skylake        06_5EH        All
+
+  Kabylake_L     06_8EH        <= 0xC
+  Kabylake       06_9EH        <= 0xD
+  =============  ============  ========
+
+Related CVEs
+------------
+
+The following CVE entry is related to this SRBDS issue:
+
+    ==============  =====  =====================================
+    CVE-2020-0543   SRBDS  Special Register Buffer Data Sampling
+    ==============  =====  =====================================
+
+Attack scenarios
+----------------
+An unprivileged user can extract values returned from RDRAND and RDSEED
+executed on another core or sibling thread using MDS techniques.
+
+
+Mitigation mechanism
+-------------------
+Intel will release microcode updates that modify the RDRAND, RDSEED, and
+EGETKEY instructions to overwrite secret special register data in the shared
+staging buffer before the secret data can be accessed by another logical
+processor.
+
+During execution of the RDRAND, RDSEED, or EGETKEY instructions, off-core
+accesses from other logical processors will be delayed until the special
+register read is complete and the secret data in the shared staging buffer is
+overwritten.
+
+This has three effects on performance:
+
+#. RDRAND, RDSEED, or EGETKEY instructions have higher latency.
+
+#. Executing RDRAND at the same time on multiple logical processors will be
+   serialized, resulting in an overall reduction in the maximum RDRAND
+   bandwidth.
+
+#. Executing RDRAND, RDSEED or EGETKEY will delay memory accesses from other
+   logical processors that miss their core caches, with an impact similar to
+   legacy locked cache-line-split accesses.
+
+The microcode updates provide an opt-out mechanism (RNGDS_MITG_DIS) to disable
+the mitigation for RDRAND and RDSEED instructions executed outside of Intel
+Software Guard Extensions (Intel SGX) enclaves. On logical processors that
+disable the mitigation using this opt-out mechanism, RDRAND and RDSEED do not
+take longer to execute and do not impact performance of sibling logical
+processors memory accesses. The opt-out mechanism does not affect Intel SGX
+enclaves (including execution of RDRAND or RDSEED inside an enclave, as well
+as EGETKEY execution).
+
+IA32_MCU_OPT_CTRL MSR Definition
+--------------------------------
+Along with the mitigation for this issue, Intel added a new thread-scope
+IA32_MCU_OPT_CTRL MSR, (address 0x123). The presence of this MSR and
+RNGDS_MITG_DIS (bit 0) is enumerated by CPUID.(EAX=07H,ECX=0).EDX[SRBDS_CTRL =
+9]==1. This MSR is introduced through the microcode update.
+
+Setting IA32_MCU_OPT_CTRL[0] (RNGDS_MITG_DIS) to 1 for a logical processor
+disables the mitigation for RDRAND and RDSEED executed outside of an Intel SGX
+enclave on that logical processor. Opting out of the mitigation for a
+particular logical processor does not affect the RDRAND and RDSEED mitigations
+for other logical processors.
+
+Note that inside of an Intel SGX enclave, the mitigation is applied regardless
+of the value of RNGDS_MITG_DS.
+
+Mitigation control on the kernel command line
+---------------------------------------------
+The kernel command line allows control over the SRBDS mitigation at boot time
+with the option "srbds=".  The option for this is:
+
+  ============= =============================================================
+  off           This option disables SRBDS mitigation for RDRAND and RDSEED on
+                affected platforms.
+  ============= =============================================================
+
+SRBDS System Information
+-----------------------
+The Linux kernel provides vulnerability status information through sysfs.  For
+SRBDS this can be accessed by the following sysfs file:
+/sys/devices/system/cpu/vulnerabilities/srbds
+
+The possible values contained in this file are:
+
+ ============================== =============================================
+ Not affected                   Processor not vulnerable
+ Vulnerable                     Processor vulnerable and mitigation disabled
+ Vulnerable: No microcode       Processor vulnerable and microcode is missing
+                                mitigation
+ Mitigation: Microcode          Processor is vulnerable and mitigation is in
+                                effect.
+ Mitigation: TSX disabled       Processor is only vulnerable when TSX is
+                                enabled while this system was booted with TSX
+                                disabled.
+ Unknown: Dependent on
+ hypervisor status              Running on virtual guest processor that is
+                                affected but with no way to know if host
+                                processor is mitigated or vulnerable.
+ ============================== =============================================
+
+SRBDS Default mitigation
+------------------------
+This new microcode serializes processor access during execution of RDRAND,
+RDSEED ensures that the shared buffer is overwritten before it is released for
+reuse.  Use the "srbds=off" kernel command line to disable the mitigation for
+RDRAND and RDSEED.
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 7bc83f3d9bdf..5e2ce88d6eda 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4757,6 +4757,26 @@
 			the kernel will oops in either "warn" or "fatal"
 			mode.
 
+	srbds=		[X86,INTEL]
+			Control the Special Register Buffer Data Sampling
+			(SRBDS) mitigation.
+
+			Certain CPUs are vulnerable to an MDS-like
+			exploit which can leak bits from the random
+			number generator.
+
+			By default, this issue is mitigated by
+			microcode.  However, the microcode fix can cause
+			the RDRAND and RDSEED instructions to become
+			much slower.  Among other effects, this will
+			result in reduced throughput from /dev/urandom.
+
+			The microcode mitigation can be disabled with
+			the following option:
+
+			off:    Disable mitigation and remove
+				performance impact to RDRAND and RDSEED
+
 	srcutree.counter_wrap_check [KNL]
 			Specifies how frequently to check for
 			grace-period sequence counter wrap for the
diff --git a/Makefile b/Makefile
index 2dd4f37c9f10..a6dda75d18cd 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 VERSION = 5
 PATCHLEVEL = 7
-SUBLEVEL = 1
+SUBLEVEL = 2
 EXTRAVERSION =
 NAME = Kleptomaniac Octopus
 
diff --git a/arch/x86/include/asm/cpu_device_id.h b/arch/x86/include/asm/cpu_device_id.h
index cf3d621c6892..10426cd56dca 100644
--- a/arch/x86/include/asm/cpu_device_id.h
+++ b/arch/x86/include/asm/cpu_device_id.h
@@ -20,12 +20,14 @@
 #define X86_CENTAUR_FAM6_C7_D		0xd
 #define X86_CENTAUR_FAM6_NANO		0xf
 
+#define X86_STEPPINGS(mins, maxs)    GENMASK(maxs, mins)
 /**
- * X86_MATCH_VENDOR_FAM_MODEL_FEATURE - Base macro for CPU matching
+ * X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE - Base macro for CPU matching
  * @_vendor:	The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
  *		The name is expanded to X86_VENDOR_@_vendor
  * @_family:	The family number or X86_FAMILY_ANY
  * @_model:	The model number, model constant or X86_MODEL_ANY
+ * @_steppings:	Bitmask for steppings, stepping constant or X86_STEPPING_ANY
  * @_feature:	A X86_FEATURE bit or X86_FEATURE_ANY
  * @_data:	Driver specific data or NULL. The internal storage
  *		format is unsigned long. The supplied value, pointer
@@ -37,15 +39,34 @@
  * into another macro at the usage site for good reasons, then please
  * start this local macro with X86_MATCH to allow easy grepping.
  */
-#define X86_MATCH_VENDOR_FAM_MODEL_FEATURE(_vendor, _family, _model,	\
-					   _feature, _data) {		\
+#define X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(_vendor, _family, _model, \
+						    _steppings, _feature, _data) { \
 	.vendor		= X86_VENDOR_##_vendor,				\
 	.family		= _family,					\
 	.model		= _model,					\
+	.steppings	= _steppings,					\
 	.feature	= _feature,					\
 	.driver_data	= (unsigned long) _data				\
 }
 
+/**
+ * X86_MATCH_VENDOR_FAM_MODEL_FEATURE - Macro for CPU matching
+ * @_vendor:	The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
+ *		The name is expanded to X86_VENDOR_@_vendor
+ * @_family:	The family number or X86_FAMILY_ANY
+ * @_model:	The model number, model constant or X86_MODEL_ANY
+ * @_feature:	A X86_FEATURE bit or X86_FEATURE_ANY
+ * @_data:	Driver specific data or NULL. The internal storage
+ *		format is unsigned long. The supplied value, pointer
+ *		etc. is casted to unsigned long internally.
+ *
+ * The steppings arguments of X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE() is
+ * set to wildcards.
+ */
+#define X86_MATCH_VENDOR_FAM_MODEL_FEATURE(vendor, family, model, feature, data) \
+	X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(vendor, family, model, \
+						X86_STEPPING_ANY, feature, data)
+
 /**
  * X86_MATCH_VENDOR_FAM_FEATURE - Macro for matching vendor, family and CPU feature
  * @vendor:	The vendor name, e.g. INTEL, AMD, HYGON, ..., ANY
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index db189945e9b0..02dabc9e77b0 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -362,6 +362,7 @@
 #define X86_FEATURE_AVX512_4FMAPS	(18*32+ 3) /* AVX-512 Multiply Accumulation Single precision */
 #define X86_FEATURE_FSRM		(18*32+ 4) /* Fast Short Rep Mov */
 #define X86_FEATURE_AVX512_VP2INTERSECT (18*32+ 8) /* AVX-512 Intersect for D/Q */
+#define X86_FEATURE_SRBDS_CTRL		(18*32+ 9) /* "" SRBDS mitigation MSR available */
 #define X86_FEATURE_MD_CLEAR		(18*32+10) /* VERW clears CPU buffers */
 #define X86_FEATURE_TSX_FORCE_ABORT	(18*32+13) /* "" TSX_FORCE_ABORT */
 #define X86_FEATURE_PCONFIG		(18*32+18) /* Intel PCONFIG */
@@ -407,5 +408,6 @@
 #define X86_BUG_SWAPGS			X86_BUG(21) /* CPU is affected by speculation through SWAPGS */
 #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 */
 
 #endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 12c9684d59ba..3efde600a674 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -128,6 +128,10 @@
 #define TSX_CTRL_RTM_DISABLE		BIT(0)	/* Disable RTM feature */
 #define TSX_CTRL_CPUID_CLEAR		BIT(1)	/* Disable TSX enumeration */
 
+/* SRBDS support */
+#define MSR_IA32_MCU_OPT_CTRL		0x00000123
+#define RNGDS_MITG_DIS			BIT(0)
+
 #define MSR_IA32_SYSENTER_CS		0x00000174
 #define MSR_IA32_SYSENTER_ESP		0x00000175
 #define MSR_IA32_SYSENTER_EIP		0x00000176
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index ed54b3b21c39..56978cb06149 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -41,6 +41,7 @@ static void __init l1tf_select_mitigation(void);
 static void __init mds_select_mitigation(void);
 static void __init mds_print_mitigation(void);
 static void __init taa_select_mitigation(void);
+static void __init srbds_select_mitigation(void);
 
 /* The base value of the SPEC_CTRL MSR that always has to be preserved. */
 u64 x86_spec_ctrl_base;
@@ -108,6 +109,7 @@ void __init check_bugs(void)
 	l1tf_select_mitigation();
 	mds_select_mitigation();
 	taa_select_mitigation();
+	srbds_select_mitigation();
 
 	/*
 	 * As MDS and TAA mitigations are inter-related, print MDS
@@ -397,6 +399,97 @@ static int __init tsx_async_abort_parse_cmdline(char *str)
 }
 early_param("tsx_async_abort", tsx_async_abort_parse_cmdline);
 
+#undef pr_fmt
+#define pr_fmt(fmt)	"SRBDS: " fmt
+
+enum srbds_mitigations {
+	SRBDS_MITIGATION_OFF,
+	SRBDS_MITIGATION_UCODE_NEEDED,
+	SRBDS_MITIGATION_FULL,
+	SRBDS_MITIGATION_TSX_OFF,
+	SRBDS_MITIGATION_HYPERVISOR,
+};
+
+static enum srbds_mitigations srbds_mitigation __ro_after_init = SRBDS_MITIGATION_FULL;
+
+static const char * const srbds_strings[] = {
+	[SRBDS_MITIGATION_OFF]		= "Vulnerable",
+	[SRBDS_MITIGATION_UCODE_NEEDED]	= "Vulnerable: No microcode",
+	[SRBDS_MITIGATION_FULL]		= "Mitigation: Microcode",
+	[SRBDS_MITIGATION_TSX_OFF]	= "Mitigation: TSX disabled",
+	[SRBDS_MITIGATION_HYPERVISOR]	= "Unknown: Dependent on hypervisor status",
+};
+
+static bool srbds_off;
+
+void update_srbds_msr(void)
+{
+	u64 mcu_ctrl;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return;
+
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return;
+
+	if (srbds_mitigation == SRBDS_MITIGATION_UCODE_NEEDED)
+		return;
+
+	rdmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+
+	switch (srbds_mitigation) {
+	case SRBDS_MITIGATION_OFF:
+	case SRBDS_MITIGATION_TSX_OFF:
+		mcu_ctrl |= RNGDS_MITG_DIS;
+		break;
+	case SRBDS_MITIGATION_FULL:
+		mcu_ctrl &= ~RNGDS_MITG_DIS;
+		break;
+	default:
+		break;
+	}
+
+	wrmsrl(MSR_IA32_MCU_OPT_CTRL, mcu_ctrl);
+}
+
+static void __init srbds_select_mitigation(void)
+{
+	u64 ia32_cap;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return;
+
+	/*
+	 * Check to see if this is one of the MDS_NO systems supporting
+	 * TSX that are only exposed to SRBDS when TSX is enabled.
+	 */
+	ia32_cap = x86_read_arch_cap_msr();
+	if ((ia32_cap & ARCH_CAP_MDS_NO) && !boot_cpu_has(X86_FEATURE_RTM))
+		srbds_mitigation = SRBDS_MITIGATION_TSX_OFF;
+	else if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		srbds_mitigation = SRBDS_MITIGATION_HYPERVISOR;
+	else if (!boot_cpu_has(X86_FEATURE_SRBDS_CTRL))
+		srbds_mitigation = SRBDS_MITIGATION_UCODE_NEEDED;
+	else if (cpu_mitigations_off() || srbds_off)
+		srbds_mitigation = SRBDS_MITIGATION_OFF;
+
+	update_srbds_msr();
+	pr_info("%s\n", srbds_strings[srbds_mitigation]);
+}
+
+static int __init srbds_parse_cmdline(char *str)
+{
+	if (!str)
+		return -EINVAL;
+
+	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+		return 0;
+
+	srbds_off = !strcmp(str, "off");
+	return 0;
+}
+early_param("srbds", srbds_parse_cmdline);
+
 #undef pr_fmt
 #define pr_fmt(fmt)     "Spectre V1 : " fmt
 
@@ -1528,6 +1621,11 @@ static char *ibpb_state(void)
 	return "";
 }
 
+static ssize_t srbds_show_state(char *buf)
+{
+	return sprintf(buf, "%s\n", srbds_strings[srbds_mitigation]);
+}
+
 static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr,
 			       char *buf, unsigned int bug)
 {
@@ -1572,6 +1670,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
 	case X86_BUG_ITLB_MULTIHIT:
 		return itlb_multihit_show_state(buf);
 
+	case X86_BUG_SRBDS:
+		return srbds_show_state(buf);
+
 	default:
 		break;
 	}
@@ -1618,4 +1719,9 @@ ssize_t cpu_show_itlb_multihit(struct device *dev, struct device_attribute *attr
 {
 	return cpu_show_common(dev, attr, buf, X86_BUG_ITLB_MULTIHIT);
 }
+
+ssize_t cpu_show_srbds(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_SRBDS);
+}
 #endif
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index bed0cb83fe24..8293ee514975 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1075,9 +1075,30 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = {
 	{}
 };
 
-static bool __init cpu_matches(unsigned long which)
+#define VULNBL_INTEL_STEPPINGS(model, steppings, issues)		   \
+	X86_MATCH_VENDOR_FAM_MODEL_STEPPINGS_FEATURE(INTEL, 6,		   \
+					    INTEL_FAM6_##model, steppings, \
+					    X86_FEATURE_ANY, issues)
+
+#define SRBDS		BIT(0)
+
+static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = {
+	VULNBL_INTEL_STEPPINGS(IVYBRIDGE,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL,		X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL_L,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(HASWELL_G,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(BROADWELL_G,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(BROADWELL,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(SKYLAKE_L,	X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(SKYLAKE,		X86_STEPPING_ANY,		SRBDS),
+	VULNBL_INTEL_STEPPINGS(KABYLAKE_L,	X86_STEPPINGS(0x0, 0xC),	SRBDS),
+	VULNBL_INTEL_STEPPINGS(KABYLAKE,	X86_STEPPINGS(0x0, 0xD),	SRBDS),
+	{}
+};
+
+static bool __init cpu_matches(const struct x86_cpu_id *table, unsigned long which)
 {
-	const struct x86_cpu_id *m = x86_match_cpu(cpu_vuln_whitelist);
+	const struct x86_cpu_id *m = x86_match_cpu(table);
 
 	return m && !!(m->driver_data & which);
 }
@@ -1097,31 +1118,34 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
 	u64 ia32_cap = x86_read_arch_cap_msr();
 
 	/* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */
-	if (!cpu_matches(NO_ITLB_MULTIHIT) && !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
+	if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) &&
+	    !(ia32_cap & ARCH_CAP_PSCHANGE_MC_NO))
 		setup_force_cpu_bug(X86_BUG_ITLB_MULTIHIT);
 
-	if (cpu_matches(NO_SPECULATION))
+	if (cpu_matches(cpu_vuln_whitelist, NO_SPECULATION))
 		return;
 
 	setup_force_cpu_bug(X86_BUG_SPECTRE_V1);
 
-	if (!cpu_matches(NO_SPECTRE_V2))
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SPECTRE_V2))
 		setup_force_cpu_bug(X86_BUG_SPECTRE_V2);
 
-	if (!cpu_matches(NO_SSB) && !(ia32_cap & ARCH_CAP_SSB_NO) &&
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SSB) &&
+	    !(ia32_cap & ARCH_CAP_SSB_NO) &&
 	   !cpu_has(c, X86_FEATURE_AMD_SSB_NO))
 		setup_force_cpu_bug(X86_BUG_SPEC_STORE_BYPASS);
 
 	if (ia32_cap & ARCH_CAP_IBRS_ALL)
 		setup_force_cpu_cap(X86_FEATURE_IBRS_ENHANCED);
 
-	if (!cpu_matches(NO_MDS) && !(ia32_cap & ARCH_CAP_MDS_NO)) {
+	if (!cpu_matches(cpu_vuln_whitelist, NO_MDS) &&
+	    !(ia32_cap & ARCH_CAP_MDS_NO)) {
 		setup_force_cpu_bug(X86_BUG_MDS);
-		if (cpu_matches(MSBDS_ONLY))
+		if (cpu_matches(cpu_vuln_whitelist, MSBDS_ONLY))
 			setup_force_cpu_bug(X86_BUG_MSBDS_ONLY);
 	}
 
-	if (!cpu_matches(NO_SWAPGS))
+	if (!cpu_matches(cpu_vuln_whitelist, NO_SWAPGS))
 		setup_force_cpu_bug(X86_BUG_SWAPGS);
 
 	/*
@@ -1139,7 +1163,16 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
 	     (ia32_cap & ARCH_CAP_TSX_CTRL_MSR)))
 		setup_force_cpu_bug(X86_BUG_TAA);
 
-	if (cpu_matches(NO_MELTDOWN))
+	/*
+	 * SRBDS affects CPUs which support RDRAND or RDSEED and are listed
+	 * in the vulnerability blacklist.
+	 */
+	if ((cpu_has(c, X86_FEATURE_RDRAND) ||
+	     cpu_has(c, X86_FEATURE_RDSEED)) &&
+	    cpu_matches(cpu_vuln_blacklist, SRBDS))
+		    setup_force_cpu_bug(X86_BUG_SRBDS);
+
+	if (cpu_matches(cpu_vuln_whitelist, NO_MELTDOWN))
 		return;
 
 	/* Rogue Data Cache Load? No! */
@@ -1148,7 +1181,7 @@ static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
 
 	setup_force_cpu_bug(X86_BUG_CPU_MELTDOWN);
 
-	if (cpu_matches(NO_L1TF))
+	if (cpu_matches(cpu_vuln_whitelist, NO_L1TF))
 		return;
 
 	setup_force_cpu_bug(X86_BUG_L1TF);
@@ -1591,6 +1624,7 @@ void identify_secondary_cpu(struct cpuinfo_x86 *c)
 	mtrr_ap_init();
 	validate_apic_and_package_id(c);
 	x86_spec_ctrl_setup_ap();
+	update_srbds_msr();
 }
 
 static __init int setup_noclflush(char *arg)
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 37fdefd14f28..fb538fccd24c 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -77,6 +77,7 @@ extern void detect_ht(struct cpuinfo_x86 *c);
 unsigned int aperfmperf_get_khz(int cpu);
 
 extern void x86_spec_ctrl_setup_ap(void);
+extern void update_srbds_msr(void);
 
 extern u64 x86_read_arch_cap_msr(void);
 
diff --git a/arch/x86/kernel/cpu/match.c b/arch/x86/kernel/cpu/match.c
index d3482eb43ff3..ad6776081e60 100644
--- a/arch/x86/kernel/cpu/match.c
+++ b/arch/x86/kernel/cpu/match.c
@@ -39,13 +39,18 @@ const struct x86_cpu_id *x86_match_cpu(const struct x86_cpu_id *match)
 	const struct x86_cpu_id *m;
 	struct cpuinfo_x86 *c = &boot_cpu_data;
 
-	for (m = match; m->vendor | m->family | m->model | m->feature; m++) {
+	for (m = match;
+	     m->vendor | m->family | m->model | m->steppings | m->feature;
+	     m++) {
 		if (m->vendor != X86_VENDOR_ANY && c->x86_vendor != m->vendor)
 			continue;
 		if (m->family != X86_FAMILY_ANY && c->x86 != m->family)
 			continue;
 		if (m->model != X86_MODEL_ANY && c->x86_model != m->model)
 			continue;
+		if (m->steppings != X86_STEPPING_ANY &&
+		    !(BIT(c->x86_stepping) & m->steppings))
+			continue;
 		if (m->feature != X86_FEATURE_ANY && !cpu_has(c, m->feature))
 			continue;
 		return m;
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 9a1c00fbbaef..d2136ab9b14a 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -562,6 +562,12 @@ ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
 	return sprintf(buf, "Not affected\n");
 }
 
+ssize_t __weak cpu_show_srbds(struct device *dev,
+			      struct device_attribute *attr, char *buf)
+{
+	return sprintf(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);
@@ -570,6 +576,7 @@ static DEVICE_ATTR(l1tf, 0444, cpu_show_l1tf, NULL);
 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 struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_meltdown.attr,
@@ -580,6 +587,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_mds.attr,
 	&dev_attr_tsx_async_abort.attr,
 	&dev_attr_itlb_multihit.attr,
+	&dev_attr_srbds.attr,
 	NULL
 };
 
diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
index 2df88d2b880a..0e2068ec068b 100644
--- a/drivers/iio/adc/stm32-adc-core.c
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -65,12 +65,14 @@ struct stm32_adc_priv;
  * @clk_sel:	clock selection routine
  * @max_clk_rate_hz: maximum analog clock rate (Hz, from datasheet)
  * @has_syscfg: SYSCFG capability flags
+ * @num_irqs:	number of interrupt lines
  */
 struct stm32_adc_priv_cfg {
 	const struct stm32_adc_common_regs *regs;
 	int (*clk_sel)(struct platform_device *, struct stm32_adc_priv *);
 	u32 max_clk_rate_hz;
 	unsigned int has_syscfg;
+	unsigned int num_irqs;
 };
 
 /**
@@ -375,21 +377,15 @@ static int stm32_adc_irq_probe(struct platform_device *pdev,
 	struct device_node *np = pdev->dev.of_node;
 	unsigned int i;
 
-	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
+	/*
+	 * Interrupt(s) must be provided, depending on the compatible:
+	 * - stm32f4/h7 shares a common interrupt line.
+	 * - stm32mp1, has one line per ADC
+	 */
+	for (i = 0; i < priv->cfg->num_irqs; i++) {
 		priv->irq[i] = platform_get_irq(pdev, i);
-		if (priv->irq[i] < 0) {
-			/*
-			 * At least one interrupt must be provided, make others
-			 * optional:
-			 * - stm32f4/h7 shares a common interrupt.
-			 * - stm32mp1, has one line per ADC (either for ADC1,
-			 *   ADC2 or both).
-			 */
-			if (i && priv->irq[i] == -ENXIO)
-				continue;
-
+		if (priv->irq[i] < 0)
 			return priv->irq[i];
-		}
 	}
 
 	priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
@@ -400,9 +396,7 @@ static int stm32_adc_irq_probe(struct platform_device *pdev,
 		return -ENOMEM;
 	}
 
-	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
-		if (priv->irq[i] < 0)
-			continue;
+	for (i = 0; i < priv->cfg->num_irqs; i++) {
 		irq_set_chained_handler(priv->irq[i], stm32_adc_irq_handler);
 		irq_set_handler_data(priv->irq[i], priv);
 	}
@@ -420,11 +414,8 @@ static void stm32_adc_irq_remove(struct platform_device *pdev,
 		irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
 	irq_domain_remove(priv->domain);
 
-	for (i = 0; i < STM32_ADC_MAX_ADCS; i++) {
-		if (priv->irq[i] < 0)
-			continue;
+	for (i = 0; i < priv->cfg->num_irqs; i++)
 		irq_set_chained_handler(priv->irq[i], NULL);
-	}
 }
 
 static int stm32_adc_core_switches_supply_en(struct stm32_adc_priv *priv,
@@ -817,6 +808,7 @@ static const struct stm32_adc_priv_cfg stm32f4_adc_priv_cfg = {
 	.regs = &stm32f4_adc_common_regs,
 	.clk_sel = stm32f4_adc_clk_sel,
 	.max_clk_rate_hz = 36000000,
+	.num_irqs = 1,
 };
 
 static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
@@ -824,6 +816,7 @@ static const struct stm32_adc_priv_cfg stm32h7_adc_priv_cfg = {
 	.clk_sel = stm32h7_adc_clk_sel,
 	.max_clk_rate_hz = 36000000,
 	.has_syscfg = HAS_VBOOSTER,
+	.num_irqs = 1,
 };
 
 static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
@@ -831,6 +824,7 @@ static const struct stm32_adc_priv_cfg stm32mp1_adc_priv_cfg = {
 	.clk_sel = stm32h7_adc_clk_sel,
 	.max_clk_rate_hz = 40000000,
 	.has_syscfg = HAS_VBOOSTER | HAS_ANASWVDD,
+	.num_irqs = 2,
 };
 
 static const struct of_device_id stm32_adc_of_match[] = {
diff --git a/drivers/iio/chemical/pms7003.c b/drivers/iio/chemical/pms7003.c
index 23c9ab252470..07bb90d72434 100644
--- a/drivers/iio/chemical/pms7003.c
+++ b/drivers/iio/chemical/pms7003.c
@@ -73,6 +73,11 @@ struct pms7003_state {
 	struct pms7003_frame frame;
 	struct completion frame_ready;
 	struct mutex lock; /* must be held whenever state gets touched */
+	/* Used to construct scan to push to the IIO buffer */
+	struct {
+		u16 data[3]; /* PM1, PM2P5, PM10 */
+		s64 ts;
+	} scan;
 };
 
 static int pms7003_do_cmd(struct pms7003_state *state, enum pms7003_cmd cmd)
@@ -104,7 +109,6 @@ static irqreturn_t pms7003_trigger_handler(int irq, void *p)
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct pms7003_state *state = iio_priv(indio_dev);
 	struct pms7003_frame *frame = &state->frame;
-	u16 data[3 + 1 + 4]; /* PM1, PM2P5, PM10, padding, timestamp */
 	int ret;
 
 	mutex_lock(&state->lock);
@@ -114,12 +118,15 @@ static irqreturn_t pms7003_trigger_handler(int irq, void *p)
 		goto err;
 	}
 
-	data[PM1] = pms7003_get_pm(frame->data + PMS7003_PM1_OFFSET);
-	data[PM2P5] = pms7003_get_pm(frame->data + PMS7003_PM2P5_OFFSET);
-	data[PM10] = pms7003_get_pm(frame->data + PMS7003_PM10_OFFSET);
+	state->scan.data[PM1] =
+		pms7003_get_pm(frame->data + PMS7003_PM1_OFFSET);
+	state->scan.data[PM2P5] =
+		pms7003_get_pm(frame->data + PMS7003_PM2P5_OFFSET);
+	state->scan.data[PM10] =
+		pms7003_get_pm(frame->data + PMS7003_PM10_OFFSET);
 	mutex_unlock(&state->lock);
 
-	iio_push_to_buffers_with_timestamp(indio_dev, data,
+	iio_push_to_buffers_with_timestamp(indio_dev, &state->scan,
 					   iio_get_time_ns(indio_dev));
 err:
 	iio_trigger_notify_done(indio_dev->trig);
diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c
index acb9f8ecbb3d..a88c1fb875a0 100644
--- a/drivers/iio/chemical/sps30.c
+++ b/drivers/iio/chemical/sps30.c
@@ -230,15 +230,18 @@ static irqreturn_t sps30_trigger_handler(int irq, void *p)
 	struct iio_dev *indio_dev = pf->indio_dev;
 	struct sps30_state *state = iio_priv(indio_dev);
 	int ret;
-	s32 data[4 + 2]; /* PM1, PM2P5, PM4, PM10, timestamp */
+	struct {
+		s32 data[4]; /* PM1, PM2P5, PM4, PM10 */
+		s64 ts;
+	} scan;
 
 	mutex_lock(&state->lock);
-	ret = sps30_do_meas(state, data, 4);
+	ret = sps30_do_meas(state, scan.data, ARRAY_SIZE(scan.data));
 	mutex_unlock(&state->lock);
 	if (ret)
 		goto err;
 
-	iio_push_to_buffers_with_timestamp(indio_dev, data,
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan,
 					   iio_get_time_ns(indio_dev));
 err:
 	iio_trigger_notify_done(indio_dev->trig);
diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index ec803c1e81df..5d476f174a90 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -219,7 +219,6 @@ static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
 				u8 rdy_mask, u8 data_reg, int *val)
 {
 	int tries = 20;
-	__be16 buf;
 	int ret;
 
 	mutex_lock(&data->vcnl4000_lock);
@@ -246,13 +245,12 @@ static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
 		goto fail;
 	}
 
-	ret = i2c_smbus_read_i2c_block_data(data->client,
-		data_reg, sizeof(buf), (u8 *) &buf);
+	ret = i2c_smbus_read_word_swapped(data->client, data_reg);
 	if (ret < 0)
 		goto fail;
 
 	mutex_unlock(&data->vcnl4000_lock);
-	*val = be16_to_cpu(buf);
+	*val = ret;
 
 	return 0;
 
diff --git a/drivers/nvmem/qfprom.c b/drivers/nvmem/qfprom.c
index d057f1bfb2e9..8a91717600be 100644
--- a/drivers/nvmem/qfprom.c
+++ b/drivers/nvmem/qfprom.c
@@ -27,25 +27,11 @@ static int qfprom_reg_read(void *context,
 	return 0;
 }
 
-static int qfprom_reg_write(void *context,
-			 unsigned int reg, void *_val, size_t bytes)
-{
-	struct qfprom_priv *priv = context;
-	u8 *val = _val;
-	int i = 0, words = bytes;
-
-	while (words--)
-		writeb(*val++, priv->base + reg + i++);
-
-	return 0;
-}
-
 static struct nvmem_config econfig = {
 	.name = "qfprom",
 	.stride = 1,
 	.word_size = 1,
 	.reg_read = qfprom_reg_read,
-	.reg_write = qfprom_reg_write,
 };
 
 static int qfprom_probe(struct platform_device *pdev)
diff --git a/drivers/staging/rtl8712/wifi.h b/drivers/staging/rtl8712/wifi.h
index be731f1a2209..91b65731fcaa 100644
--- a/drivers/staging/rtl8712/wifi.h
+++ b/drivers/staging/rtl8712/wifi.h
@@ -440,7 +440,7 @@ static inline unsigned char *get_hdr_bssid(unsigned char *pframe)
 /* block-ack parameters */
 #define IEEE80211_ADDBA_PARAM_POLICY_MASK 0x0002
 #define IEEE80211_ADDBA_PARAM_TID_MASK 0x003C
-#define IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK 0xFFA0
+#define IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK 0xFFC0
 #define IEEE80211_DELBA_PARAM_TID_MASK 0xF000
 #define IEEE80211_DELBA_PARAM_INITIATOR_MASK 0x0800
 
@@ -532,13 +532,6 @@ struct ieee80211_ht_addt_info {
 #define IEEE80211_HT_IE_NON_GF_STA_PRSNT	0x0004
 #define IEEE80211_HT_IE_NON_HT_STA_PRSNT	0x0010
 
-/* block-ack parameters */
-#define IEEE80211_ADDBA_PARAM_POLICY_MASK 0x0002
-#define IEEE80211_ADDBA_PARAM_TID_MASK 0x003C
-#define IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK 0xFFA0
-#define IEEE80211_DELBA_PARAM_TID_MASK 0xF000
-#define IEEE80211_DELBA_PARAM_INITIATOR_MASK 0x0800
-
 /*
  * A-PMDU buffer sizes
  * According to IEEE802.11n spec size varies from 8K to 64K (in powers of 2)
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index 436cc51c92c3..cdcc64ea2554 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -371,15 +371,14 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 	 * tty fields and return the kref reference.
 	 */
 	if (rc) {
-		tty_port_tty_set(&hp->port, NULL);
-		tty->driver_data = NULL;
-		tty_port_put(&hp->port);
 		printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
-	} else
+	} else {
 		/* We are ready... raise DTR/RTS */
 		if (C_BAUD(tty))
 			if (hp->ops->dtr_rts)
 				hp->ops->dtr_rts(hp, 1);
+		tty_port_set_initialized(&hp->port, true);
+	}
 
 	/* Force wakeup of the polling thread */
 	hvc_kick();
@@ -389,22 +388,12 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 
 static void hvc_close(struct tty_struct *tty, struct file * filp)
 {
-	struct hvc_struct *hp;
+	struct hvc_struct *hp = tty->driver_data;
 	unsigned long flags;
 
 	if (tty_hung_up_p(filp))
 		return;
 
-	/*
-	 * No driver_data means that this close was issued after a failed
-	 * hvc_open by the tty layer's release_dev() function and we can just
-	 * exit cleanly because the kref reference wasn't made.
-	 */
-	if (!tty->driver_data)
-		return;
-
-	hp = tty->driver_data;
-
 	spin_lock_irqsave(&hp->port.lock, flags);
 
 	if (--hp->port.count == 0) {
@@ -412,6 +401,9 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
 		/* We are done with the tty pointer now. */
 		tty_port_tty_set(&hp->port, NULL);
 
+		if (!tty_port_initialized(&hp->port))
+			return;
+
 		if (C_HUPCL(tty))
 			if (hp->ops->dtr_rts)
 				hp->ops->dtr_rts(hp, 0);
@@ -428,6 +420,7 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
 		 * waking periodically to check chars_in_buffer().
 		 */
 		tty_wait_until_sent(tty, HVC_CLOSE_WAIT);
+		tty_port_set_initialized(&hp->port, false);
 	} else {
 		if (hp->port.count < 0)
 			printk(KERN_ERR "hvc_close %X: oops, count is %d\n",
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index af0688156dd0..8195a31519ea 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -63,6 +63,7 @@ config SERIAL_8250_PNP
 config SERIAL_8250_16550A_VARIANTS
 	bool "Support for variants of the 16550A serial port"
 	depends on SERIAL_8250
+	default !X86
 	help
 	  The 8250 driver can probe for many variants of the venerable 16550A
 	  serial port. Doing so takes additional time at boot.
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index 15d33fa0c925..568b2171f335 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -127,7 +127,11 @@ static DEFINE_SPINLOCK(func_buf_lock); /* guard 'func_buf'  and friends */
 static unsigned long key_down[BITS_TO_LONGS(KEY_CNT)];	/* keyboard key bitmap */
 static unsigned char shift_down[NR_SHIFT];		/* shift state counters.. */
 static bool dead_key_next;
-static int npadch = -1;					/* -1 or number assembled on pad */
+
+/* Handles a number being assembled on the number pad */
+static bool npadch_active;
+static unsigned int npadch_value;
+
 static unsigned int diacr;
 static char rep;					/* flag telling character repeat */
 
@@ -845,12 +849,12 @@ static void k_shift(struct vc_data *vc, unsigned char value, char up_flag)
 		shift_state &= ~(1 << value);
 
 	/* kludge */
-	if (up_flag && shift_state != old_state && npadch != -1) {
+	if (up_flag && shift_state != old_state && npadch_active) {
 		if (kbd->kbdmode == VC_UNICODE)
-			to_utf8(vc, npadch);
+			to_utf8(vc, npadch_value);
 		else
-			put_queue(vc, npadch & 0xff);
-		npadch = -1;
+			put_queue(vc, npadch_value & 0xff);
+		npadch_active = false;
 	}
 }
 
@@ -868,7 +872,7 @@ static void k_meta(struct vc_data *vc, unsigned char value, char up_flag)
 
 static void k_ascii(struct vc_data *vc, unsigned char value, char up_flag)
 {
-	int base;
+	unsigned int base;
 
 	if (up_flag)
 		return;
@@ -882,10 +886,12 @@ static void k_ascii(struct vc_data *vc, unsigned char value, char up_flag)
 		base = 16;
 	}
 
-	if (npadch == -1)
-		npadch = value;
-	else
-		npadch = npadch * base + value;
+	if (!npadch_active) {
+		npadch_value = 0;
+		npadch_active = true;
+	}
+
+	npadch_value = npadch_value * base + value;
 }
 
 static void k_lock(struct vc_data *vc, unsigned char value, char up_flag)
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index ded8d93834ca..f67088bb8218 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -584,7 +584,7 @@ static void acm_softint(struct work_struct *work)
 	}
 
 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
-		for (i = 0; i < ACM_NR; i++) 
+		for (i = 0; i < acm->rx_buflimit; i++)
 			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
 					acm_submit_read_urb(acm, i, GFP_NOIO);
 	}
diff --git a/drivers/usb/musb/jz4740.c b/drivers/usb/musb/jz4740.c
index e64dd30e80e7..c4fe1f4cd17a 100644
--- a/drivers/usb/musb/jz4740.c
+++ b/drivers/usb/musb/jz4740.c
@@ -30,11 +30,11 @@ static irqreturn_t jz4740_musb_interrupt(int irq, void *__hci)
 	irqreturn_t	retval = IRQ_NONE, retval_dma = IRQ_NONE;
 	struct musb	*musb = __hci;
 
-	spin_lock_irqsave(&musb->lock, flags);
-
 	if (IS_ENABLED(CONFIG_USB_INVENTRA_DMA) && musb->dma_controller)
 		retval_dma = dma_controller_irq(irq, musb->dma_controller);
 
+	spin_lock_irqsave(&musb->lock, flags);
+
 	musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB);
 	musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX);
 	musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX);
diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index d590110539ab..48178aeccf5b 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -2877,6 +2877,13 @@ static int musb_resume(struct device *dev)
 	musb_enable_interrupts(musb);
 	musb_platform_enable(musb);
 
+	/* session might be disabled in suspend */
+	if (musb->port_mode == MUSB_HOST &&
+	    !(musb->ops->quirks & MUSB_PRESERVE_SESSION)) {
+		devctl |= MUSB_DEVCTL_SESSION;
+		musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
+	}
+
 	spin_lock_irqsave(&musb->lock, flags);
 	error = musb_run_resume_work(musb);
 	if (error)
diff --git a/drivers/usb/musb/musb_debugfs.c b/drivers/usb/musb/musb_debugfs.c
index 7b6281ab62ed..30a89aa8a3e7 100644
--- a/drivers/usb/musb/musb_debugfs.c
+++ b/drivers/usb/musb/musb_debugfs.c
@@ -168,6 +168,11 @@ static ssize_t musb_test_mode_write(struct file *file,
 	u8			test;
 	char			buf[24];
 
+	memset(buf, 0x00, sizeof(buf));
+
+	if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+		return -EFAULT;
+
 	pm_runtime_get_sync(musb->controller);
 	test = musb_readb(musb->mregs, MUSB_TESTMODE);
 	if (test) {
@@ -176,11 +181,6 @@ static ssize_t musb_test_mode_write(struct file *file,
 		goto ret;
 	}
 
-	memset(buf, 0x00, sizeof(buf));
-
-	if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
-		return -EFAULT;
-
 	if (strstarts(buf, "force host full-speed"))
 		test = MUSB_TEST_FORCE_HOST | MUSB_TEST_FORCE_FS;
 
diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index c5ecdcd51ffc..89675ee29645 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -73,6 +73,8 @@
 #define CH341_LCR_CS6          0x01
 #define CH341_LCR_CS5          0x00
 
+#define CH341_QUIRK_LIMITED_PRESCALER	BIT(0)
+
 static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(0x4348, 0x5523) },
 	{ USB_DEVICE(0x1a86, 0x7523) },
@@ -87,6 +89,7 @@ struct ch341_private {
 	u8 mcr;
 	u8 msr;
 	u8 lcr;
+	unsigned long quirks;
 };
 
 static void ch341_set_termios(struct tty_struct *tty,
@@ -159,9 +162,11 @@ static const speed_t ch341_min_rates[] = {
  *		2 <= div <= 256 if fact = 0, or
  *		9 <= div <= 256 if fact = 1
  */
-static int ch341_get_divisor(speed_t speed)
+static int ch341_get_divisor(struct ch341_private *priv)
 {
 	unsigned int fact, div, clk_div;
+	speed_t speed = priv->baud_rate;
+	bool force_fact0 = false;
 	int ps;
 
 	/*
@@ -187,8 +192,12 @@ static int ch341_get_divisor(speed_t speed)
 	clk_div = CH341_CLK_DIV(ps, fact);
 	div = CH341_CLKRATE / (clk_div * speed);
 
+	/* Some devices require a lower base clock if ps < 3. */
+	if (ps < 3 && (priv->quirks & CH341_QUIRK_LIMITED_PRESCALER))
+		force_fact0 = true;
+
 	/* Halve base clock (fact = 0) if required. */
-	if (div < 9 || div > 255) {
+	if (div < 9 || div > 255 || force_fact0) {
 		div /= 2;
 		clk_div *= 2;
 		fact = 0;
@@ -227,7 +236,7 @@ static int ch341_set_baudrate_lcr(struct usb_device *dev,
 	if (!priv->baud_rate)
 		return -EINVAL;
 
-	val = ch341_get_divisor(priv->baud_rate);
+	val = ch341_get_divisor(priv);
 	if (val < 0)
 		return -EINVAL;
 
@@ -308,6 +317,54 @@ out:	kfree(buffer);
 	return r;
 }
 
+static int ch341_detect_quirks(struct usb_serial_port *port)
+{
+	struct ch341_private *priv = usb_get_serial_port_data(port);
+	struct usb_device *udev = port->serial->dev;
+	const unsigned int size = 2;
+	unsigned long quirks = 0;
+	char *buffer;
+	int r;
+
+	buffer = kmalloc(size, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
+
+	/*
+	 * A subset of CH34x devices does not support all features. The
+	 * prescaler is limited and there is no support for sending a RS232
+	 * break condition. A read failure when trying to set up the latter is
+	 * used to detect these devices.
+	 */
+	r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), CH341_REQ_READ_REG,
+			    USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+			    CH341_REG_BREAK, 0, buffer, size, DEFAULT_TIMEOUT);
+	if (r == -EPIPE) {
+		dev_dbg(&port->dev, "break control not supported\n");
+		quirks = CH341_QUIRK_LIMITED_PRESCALER;
+		r = 0;
+		goto out;
+	}
+
+	if (r != size) {
+		if (r >= 0)
+			r = -EIO;
+		dev_err(&port->dev, "failed to read break control: %d\n", r);
+		goto out;
+	}
+
+	r = 0;
+out:
+	kfree(buffer);
+
+	if (quirks) {
+		dev_dbg(&port->dev, "enabling quirk flags: 0x%02lx\n", quirks);
+		priv->quirks |= quirks;
+	}
+
+	return r;
+}
+
 static int ch341_port_probe(struct usb_serial_port *port)
 {
 	struct ch341_private *priv;
@@ -330,6 +387,11 @@ static int ch341_port_probe(struct usb_serial_port *port)
 		goto error;
 
 	usb_set_serial_port_data(port, priv);
+
+	r = ch341_detect_quirks(port);
+	if (r < 0)
+		goto error;
+
 	return 0;
 
 error:	kfree(priv);
diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index 8bfffca3e4ae..254a8bbeea67 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -1157,6 +1157,10 @@ static const struct usb_device_id option_ids[] = {
 	{ USB_DEVICE(TELIT_VENDOR_ID, TELIT_PRODUCT_CC864_SINGLE) },
 	{ USB_DEVICE(TELIT_VENDOR_ID, TELIT_PRODUCT_DE910_DUAL) },
 	{ USB_DEVICE(TELIT_VENDOR_ID, TELIT_PRODUCT_UE910_V2) },
+	{ USB_DEVICE_INTERFACE_CLASS(TELIT_VENDOR_ID, 0x1031, 0xff),	/* Telit LE910C1-EUX */
+	 .driver_info = NCTRL(0) | RSVD(3) },
+	{ USB_DEVICE_INTERFACE_CLASS(TELIT_VENDOR_ID, 0x1033, 0xff),	/* Telit LE910C1-EUX (ECM) */
+	 .driver_info = NCTRL(0) },
 	{ USB_DEVICE(TELIT_VENDOR_ID, TELIT_PRODUCT_LE922_USBCFG0),
 	  .driver_info = RSVD(0) | RSVD(1) | NCTRL(2) | RSVD(3) },
 	{ USB_DEVICE(TELIT_VENDOR_ID, TELIT_PRODUCT_LE922_USBCFG1),
diff --git a/drivers/usb/serial/qcserial.c b/drivers/usb/serial/qcserial.c
index ce0401d3137f..d147feae83e6 100644
--- a/drivers/usb/serial/qcserial.c
+++ b/drivers/usb/serial/qcserial.c
@@ -173,6 +173,7 @@ static const struct usb_device_id id_table[] = {
 	{DEVICE_SWI(0x413c, 0x81b3)},	/* Dell Wireless 5809e Gobi(TM) 4G LTE Mobile Broadband Card (rev3) */
 	{DEVICE_SWI(0x413c, 0x81b5)},	/* Dell Wireless 5811e QDL */
 	{DEVICE_SWI(0x413c, 0x81b6)},	/* Dell Wireless 5811e QDL */
+	{DEVICE_SWI(0x413c, 0x81cb)},	/* Dell Wireless 5816e QDL */
 	{DEVICE_SWI(0x413c, 0x81cc)},	/* Dell Wireless 5816e */
 	{DEVICE_SWI(0x413c, 0x81cf)},   /* Dell Wireless 5819 */
 	{DEVICE_SWI(0x413c, 0x81d0)},   /* Dell Wireless 5819 */
diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
index 13be21aad2f4..4b9845807bee 100644
--- a/drivers/usb/serial/usb_wwan.c
+++ b/drivers/usb/serial/usb_wwan.c
@@ -270,6 +270,10 @@ static void usb_wwan_indat_callback(struct urb *urb)
 	if (status) {
 		dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
 			__func__, status, endpoint);
+
+		/* don't resubmit on fatal errors */
+		if (status == -ESHUTDOWN || status == -ENOENT)
+			return;
 	} else {
 		if (urb->actual_length) {
 			tty_insert_flip_string(&port->port, data,
diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 4c2ddd0941a7..0754b8d71262 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -663,6 +663,7 @@ struct x86_cpu_id {
 	__u16 vendor;
 	__u16 family;
 	__u16 model;
+	__u16 steppings;
 	__u16 feature;	/* bit index */
 	kernel_ulong_t driver_data;
 };
@@ -671,6 +672,7 @@ struct x86_cpu_id {
 #define X86_VENDOR_ANY 0xffff
 #define X86_FAMILY_ANY 0
 #define X86_MODEL_ANY  0
+#define X86_STEPPING_ANY 0
 #define X86_FEATURE_ANY 0	/* Same as FPU, you can't test for that */
 
 /*
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index ece7e13f6e4a..cc2095607c74 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -867,10 +867,6 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
 	if (ret)
 		goto out;
 
-	/* uprobe_write_opcode() assumes we don't cross page boundary */
-	BUG_ON((uprobe->offset & ~PAGE_MASK) +
-			UPROBE_SWBP_INSN_SIZE > PAGE_SIZE);
-
 	smp_wmb(); /* pairs with the smp_rmb() in handle_swbp() */
 	set_bit(UPROBE_COPY_INSN, &uprobe->flags);
 
@@ -1166,6 +1162,15 @@ static int __uprobe_register(struct inode *inode, loff_t offset,
 	if (offset > i_size_read(inode))
 		return -EINVAL;
 
+	/*
+	 * This ensures that copy_from_page(), copy_to_page() and
+	 * __update_ref_ctr() can't cross page boundary.
+	 */
+	if (!IS_ALIGNED(offset, UPROBE_SWBP_INSN_SIZE))
+		return -EINVAL;
+	if (!IS_ALIGNED(ref_ctr_offset, sizeof(short)))
+		return -EINVAL;
+
  retry:
 	uprobe = alloc_uprobe(inode, offset, ref_ctr_offset);
 	if (!uprobe)
@@ -2014,6 +2019,9 @@ static int is_trap_at_addr(struct mm_struct *mm, unsigned long vaddr)
 	uprobe_opcode_t opcode;
 	int result;
 
+	if (WARN_ON_ONCE(!IS_ALIGNED(vaddr, UPROBE_SWBP_INSN_SIZE)))
+		return -EINVAL;
+
 	pagefault_disable();
 	result = __get_user(opcode, (uprobe_opcode_t __user *)vaddr);
 	pagefault_enable();