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Linux 5.15.125

DISCUSSION Greg Kroah-Hartman 1 participant 2 messages Aug 8, 2023 Stable branch

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Greg Kroah-Hartman

author maintainer
#0 lore raw

-----------------
Note, PLEASE TEST this kernel if you are on the 5.15.y tree before using it in a real workload. This was a quick release due to the obvious security fixes in it, and as such, it has not had very much testing "in the wild". Please let us know of any problems seen. Also note that the user/kernel api for the new security mitigations might be changing over time, so do not get used to them being fixed in stone just yet.
-----------------

I'm announcing the release of the 5.15.125 kernel.

All users of the 5.15 kernel series must upgrade.

The updated 5.15.y git tree can be found at:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-5.15.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         |   13 
 Documentation/admin-guide/hw-vuln/gather_data_sampling.rst |  109 +++
 Documentation/admin-guide/hw-vuln/index.rst                |    2 
 Documentation/admin-guide/hw-vuln/srso.rst                 |  133 ++++
 Documentation/admin-guide/kernel-parameters.txt            |   52 +
 Makefile                                                   |    2 
 arch/Kconfig                                               |    3 
 arch/alpha/include/asm/bugs.h                              |   20 
 arch/arm/Kconfig                                           |    1 
 arch/arm/include/asm/bugs.h                                |    4 
 arch/arm/kernel/bugs.c                                     |    3 
 arch/ia64/Kconfig                                          |    1 
 arch/ia64/include/asm/bugs.h                               |   20 
 arch/ia64/kernel/setup.c                                   |    3 
 arch/m68k/Kconfig                                          |    1 
 arch/m68k/include/asm/bugs.h                               |   21 
 arch/m68k/kernel/setup_mm.c                                |    3 
 arch/mips/Kconfig                                          |    1 
 arch/mips/include/asm/bugs.h                               |   17 
 arch/mips/kernel/setup.c                                   |   13 
 arch/parisc/include/asm/bugs.h                             |   20 
 arch/powerpc/include/asm/bugs.h                            |   15 
 arch/sh/Kconfig                                            |    1 
 arch/sh/include/asm/bugs.h                                 |   74 --
 arch/sh/include/asm/processor.h                            |    2 
 arch/sh/kernel/idle.c                                      |    1 
 arch/sh/kernel/setup.c                                     |   55 +
 arch/sparc/Kconfig                                         |    1 
 arch/sparc/include/asm/bugs.h                              |   18 
 arch/sparc/kernel/setup_32.c                               |    7 
 arch/um/Kconfig                                            |    1 
 arch/um/include/asm/bugs.h                                 |    7 
 arch/um/kernel/um_arch.c                                   |    3 
 arch/x86/Kconfig                                           |   27 
 arch/x86/include/asm/bugs.h                                |    2 
 arch/x86/include/asm/cpufeature.h                          |    7 
 arch/x86/include/asm/cpufeatures.h                         |   15 
 arch/x86/include/asm/disabled-features.h                   |    3 
 arch/x86/include/asm/fpu/internal.h                        |    2 
 arch/x86/include/asm/mem_encrypt.h                         |    7 
 arch/x86/include/asm/msr-index.h                           |   12 
 arch/x86/include/asm/nospec-branch.h                       |   18 
 arch/x86/include/asm/processor.h                           |    2 
 arch/x86/include/asm/required-features.h                   |    3 
 arch/x86/include/asm/sigframe.h                            |    2 
 arch/x86/kernel/cpu/amd.c                                  |   19 
 arch/x86/kernel/cpu/bugs.c                                 |  388 +++++++++++--
 arch/x86/kernel/cpu/common.c                               |  126 +++-
 arch/x86/kernel/cpu/cpu.h                                  |    2 
 arch/x86/kernel/fpu/init.c                                 |    8 
 arch/x86/kernel/signal.c                                   |    4 
 arch/x86/kernel/vmlinux.lds.S                              |   32 +
 arch/x86/kvm/cpuid.c                                       |    3 
 arch/x86/kvm/reverse_cpuid.h                               |    1 
 arch/x86/kvm/svm/svm.c                                     |    4 
 arch/x86/kvm/svm/vmenter.S                                 |    3 
 arch/x86/kvm/x86.c                                         |    7 
 arch/x86/lib/retpoline.S                                   |   81 ++
 arch/x86/mm/init.c                                         |    6 
 arch/x86/xen/smp_pv.c                                      |    2 
 arch/xtensa/include/asm/bugs.h                             |   18 
 drivers/base/cpu.c                                         |   16 
 drivers/net/xen-netback/netback.c                          |   15 
 include/asm-generic/bugs.h                                 |   11 
 include/linux/cpu.h                                        |    8 
 include/linux/sched/task.h                                 |    2 
 init/main.c                                                |   21 
 kernel/fork.c                                              |   37 -
 tools/arch/x86/include/asm/cpufeatures.h                   |    2 
 tools/objtool/arch/x86/decode.c                            |    5 
 70 files changed, 1139 insertions(+), 409 deletions(-)

Borislav Petkov (AMD) (7):
x86/bugs: Increase the x86 bugs vector size to two u32s x86/srso: Add a Speculative RAS Overflow mitigation x86/srso: Add IBPB_BRTYPE support
x86/srso: Add SRSO_NO support
x86/srso: Add IBPB
x86/srso: Add IBPB on VMEXIT
x86/srso: Tie SBPB bit setting to microcode patch detection

Daniel Sneddon (4):
x86/speculation: Add Gather Data Sampling mitigation x86/speculation: Add force option to GDS mitigation x86/speculation: Add Kconfig option for GDS
KVM: Add GDS_NO support to KVM

Dave Hansen (1):
Documentation/x86: Fix backwards on/off logic about YMM support

Greg Kroah-Hartman (2):
x86: fix backwards merge of GDS/SRSO bit
Linux 5.15.125

Josh Poimboeuf (1):
x86/srso: Fix return thunks in generated code

Juergen Gross (2):
x86/xen: Fix secondary processors' FPU initialization x86/mm: fix poking_init() for Xen PV guests

Kim Phillips (1):

      x86/cpu, kvm: Add support for CPUID_80000021_EAX

Peter Zijlstra (3):
x86/mm: Use mm_alloc() in poking_init()
mm: Move mm_cachep initialization to mm_init() x86/mm: Initialize text poking earlier

Ross Lagerwall (1):
xen/netback: Fix buffer overrun triggered by unusual packet

Thomas Gleixner (16):
init: Provide arch_cpu_finalize_init()
x86/cpu: Switch to arch_cpu_finalize_init()
ARM: cpu: Switch to arch_cpu_finalize_init() ia64/cpu: Switch to arch_cpu_finalize_init() m68k/cpu: Switch to arch_cpu_finalize_init() mips/cpu: Switch to arch_cpu_finalize_init()
sh/cpu: Switch to arch_cpu_finalize_init()
sparc/cpu: Switch to arch_cpu_finalize_init()
um/cpu: Switch to arch_cpu_finalize_init()
init: Remove check_bugs() leftovers
init: Invoke arch_cpu_finalize_init() earlier
init, x86: Move mem_encrypt_init() into arch_cpu_finalize_init() x86/init: Initialize signal frame size late
x86/fpu: Remove cpuinfo argument from init functions x86/fpu: Mark init functions __init
x86/fpu: Move FPU initialization into arch_cpu_finalize_init()

author maintainer
#1 lore raw
Documentation/ABI/testing/sysfs-devices-system-cpu +7 -6
index a7362b1096c4..eecbd1603349 100644
@@ -511,17 +511,18 @@ Description:	information about CPUs heterogeneity.
 		cpu_capacity: capacity of cpu#.
 
 What:		/sys/devices/system/cpu/vulnerabilities
+		/sys/devices/system/cpu/vulnerabilities/gather_data_sampling
+		/sys/devices/system/cpu/vulnerabilities/itlb_multihit
+		/sys/devices/system/cpu/vulnerabilities/l1tf
+		/sys/devices/system/cpu/vulnerabilities/mds
 		/sys/devices/system/cpu/vulnerabilities/meltdown
+		/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
+		/sys/devices/system/cpu/vulnerabilities/retbleed
+		/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
 		/sys/devices/system/cpu/vulnerabilities/spectre_v1
 		/sys/devices/system/cpu/vulnerabilities/spectre_v2
-		/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
-		/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
-		/sys/devices/system/cpu/vulnerabilities/retbleed
 Date:		January 2018
 Contact:	Linux kernel mailing list <[email protected]>
 Description:	Information about CPU vulnerabilities
Documentation/admin-guide/hw-vuln/gather_data_sampling.rst new file +109 -0

109 lines not on this page · raw message

Documentation/admin-guide/hw-vuln/index.rst +2 -0
index e0614760a99e..6828102baaa7 100644
@@ -19,3 +19,5 @@ are configurable at compile, boot or run time.
    l1d_flush.rst
    processor_mmio_stale_data.rst
    cross-thread-rsb.rst
+   gather_data_sampling.rst
+   srso
Documentation/admin-guide/hw-vuln/srso.rst new file +133 -0

133 lines not on this page · raw message

Documentation/admin-guide/kernel-parameters.txt +42 -10

76 lines not on this page · raw message

Makefile +1 -1
index 6fb94face8d7..a90f955e14ab 100644
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 VERSION = 5
 PATCHLEVEL = 15
-SUBLEVEL = 124
+SUBLEVEL = 125
 EXTRAVERSION =
 NAME = Trick or Treat
 
arch/Kconfig +3 -0
index 5987363b41c2..b45c699c2bac 100644
@@ -264,6 +264,9 @@ config ARCH_HAS_DMA_SET_UNCACHED
 config ARCH_HAS_DMA_CLEAR_UNCACHED
 	bool
 
+config ARCH_HAS_CPU_FINALIZE_INIT
+	bool
+
 # Select if arch init_task must go in the __init_task_data section
 config ARCH_TASK_STRUCT_ON_STACK
 	bool
arch/alpha/include/asm/bugs.h deleted +0 -20
deleted file mode 100644
index 78030d1c7e7e..000000000000
@@ -1,20 +0,0 @@
-/*
- *  include/asm-alpha/bugs.h
- *
- *  Copyright (C) 1994  Linus Torvalds
- */
-
-/*
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
- * Needs:
- *	void check_bugs(void);
- */
-
-/*
- * I don't know of any alpha bugs yet.. Nice chip
- */
-
-static void check_bugs(void)
-{
-}
arch/arm/Kconfig +1 -0
index a8ae17f5740d..f2fbb170d813 100644
@@ -4,6 +4,7 @@ config ARM
 	default y
 	select ARCH_32BIT_OFF_T
 	select ARCH_HAS_BINFMT_FLAT
+	select ARCH_HAS_CPU_FINALIZE_INIT if MMU
 	select ARCH_HAS_DEBUG_VIRTUAL if MMU
 	select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
 	select ARCH_HAS_ELF_RANDOMIZE
arch/arm/include/asm/bugs.h +0 -4
index 97a312ba0840..fe385551edec 100644
@@ -1,7 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- *  arch/arm/include/asm/bugs.h
- *
  *  Copyright (C) 1995-2003 Russell King
  */
 #ifndef __ASM_BUGS_H
@@ -10,10 +8,8 @@
 extern void check_writebuffer_bugs(void);
 
 #ifdef CONFIG_MMU
-extern void check_bugs(void);
 extern void check_other_bugs(void);
 #else
-#define check_bugs() do { } while (0)
 #define check_other_bugs() do { } while (0)
 #endif
 
arch/arm/kernel/bugs.c +2 -1
index 14c8dbbb7d2d..087bce6ec8e9 100644
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
+#include <linux/cpu.h>
 #include <asm/bugs.h>
 #include <asm/proc-fns.h>
 
@@ -11,7 +12,7 @@ void check_other_bugs(void)
 #endif
 }
 
-void __init check_bugs(void)
+void __init arch_cpu_finalize_init(void)
 {
 	check_writebuffer_bugs();
 	check_other_bugs();
arch/ia64/Kconfig +1 -0
index b1f2b6ac9b1d..89869aff8ca2 100644
@@ -8,6 +8,7 @@ menu "Processor type and features"
 
 config IA64
 	bool
+	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_DMA_MARK_CLEAN
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
arch/ia64/include/asm/bugs.h deleted +0 -20
deleted file mode 100644
index 0d6b9bded56c..000000000000
@@ -1,20 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
- * Needs:
- *	void check_bugs(void);
- *
- * Based on <asm-alpha/bugs.h>.
- *
- * Modified 1998, 1999, 2003
- *	David Mosberger-Tang <[email protected]>,  Hewlett-Packard Co.
- */
-#ifndef _ASM_IA64_BUGS_H
-#define _ASM_IA64_BUGS_H
-
-#include <asm/processor.h>
-
-extern void check_bugs (void);
-
-#endif /* _ASM_IA64_BUGS_H */
arch/ia64/kernel/setup.c +1 -2
index 31fb84de2d21..041681e5de47 100644
@@ -1070,8 +1070,7 @@ cpu_init (void)
 	}
 }
 
-void __init
-check_bugs (void)
+void __init arch_cpu_finalize_init(void)
 {
 	ia64_patch_mckinley_e9((unsigned long) __start___mckinley_e9_bundles,
 			       (unsigned long) __end___mckinley_e9_bundles);
arch/m68k/Kconfig +1 -0
index 0b50da08a9c5..810056d8ea67 100644
@@ -4,6 +4,7 @@ config M68K
 	default y
 	select ARCH_32BIT_OFF_T
 	select ARCH_HAS_BINFMT_FLAT
+	select ARCH_HAS_CPU_FINALIZE_INIT if MMU
 	select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE
 	select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS
arch/m68k/include/asm/bugs.h deleted +0 -21
deleted file mode 100644
index 745530651e0b..000000000000
@@ -1,21 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- *  include/asm-m68k/bugs.h
- *
- *  Copyright (C) 1994  Linus Torvalds
- */
-
-/*
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
- * Needs:
- *	void check_bugs(void);
- */
-
-#ifdef CONFIG_MMU
-extern void check_bugs(void);	/* in arch/m68k/kernel/setup.c */
-#else
-static void check_bugs(void)
-{
-}
-#endif
arch/m68k/kernel/setup_mm.c +2 -1
index f24410a54dcb..868641a53623 100644
@@ -10,6 +10,7 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/cpu.h>
 #include <linux/mm.h>
 #include <linux/sched.h>
 #include <linux/delay.h>
@@ -512,7 +513,7 @@ static int __init proc_hardware_init(void)
 module_init(proc_hardware_init);
 #endif
 
-void check_bugs(void)
+void __init arch_cpu_finalize_init(void)
 {
 #if defined(CONFIG_FPU) && !defined(CONFIG_M68KFPU_EMU)
 	if (m68k_fputype == 0) {
arch/mips/Kconfig +1 -0
index 56c0f75e7a76..13b09c7516e9 100644
@@ -4,6 +4,7 @@ config MIPS
 	default y
 	select ARCH_32BIT_OFF_T if !64BIT
 	select ARCH_BINFMT_ELF_STATE if MIPS_FP_SUPPORT
+	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_DEBUG_VIRTUAL if !64BIT
 	select ARCH_HAS_FORTIFY_SOURCE
 	select ARCH_HAS_KCOV
arch/mips/include/asm/bugs.h +0 -17
index d72dc6e1cf3c..8d4cf29861b8 100644
@@ -1,17 +1,11 @@
 /* SPDX-License-Identifier: GPL-2.0 */
 /*
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
  * Copyright (C) 2007  Maciej W. Rozycki
- *
- * Needs:
- *	void check_bugs(void);
  */
 #ifndef _ASM_BUGS_H
 #define _ASM_BUGS_H
 
 #include <linux/bug.h>
-#include <linux/delay.h>
 #include <linux/smp.h>
 
 #include <asm/cpu.h>
@@ -30,17 +24,6 @@ static inline void check_bugs_early(void)
 		check_bugs64_early();
 }
 
-static inline void check_bugs(void)
-{
-	unsigned int cpu = smp_processor_id();
-
-	cpu_data[cpu].udelay_val = loops_per_jiffy;
-	check_bugs32();
-
-	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
-		check_bugs64();
-}
-
 static inline int r4k_daddiu_bug(void)
 {
 	if (!IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
arch/mips/kernel/setup.c +13 -0
index c8d849d8a844..145f905fb362 100644
@@ -11,6 +11,8 @@
  * Copyright (C) 2000, 2001, 2002, 2007	 Maciej W. Rozycki
  */
 #include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
 #include <linux/ioport.h>
 #include <linux/export.h>
 #include <linux/screen_info.h>
@@ -810,3 +812,14 @@ static int __init setnocoherentio(char *str)
 }
 early_param("nocoherentio", setnocoherentio);
 #endif
+
+void __init arch_cpu_finalize_init(void)
+{
+	unsigned int cpu = smp_processor_id();
+
+	cpu_data[cpu].udelay_val = loops_per_jiffy;
+	check_bugs32();
+
+	if (IS_ENABLED(CONFIG_CPU_R4X00_BUGS64))
+		check_bugs64();
+}
arch/parisc/include/asm/bugs.h deleted +0 -20
deleted file mode 100644
index 0a7f9db6bd1c..000000000000
@@ -1,20 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- *  include/asm-parisc/bugs.h
- *
- *  Copyright (C) 1999	Mike Shaver
- */
-
-/*
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
- * Needs:
- *	void check_bugs(void);
- */
-
-#include <asm/processor.h>
-
-static inline void check_bugs(void)
-{
-//	identify_cpu(&boot_cpu_data);
-}
arch/powerpc/include/asm/bugs.h deleted +0 -15
deleted file mode 100644
index 01b8f6ca4dbb..000000000000
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-#ifndef _ASM_POWERPC_BUGS_H
-#define _ASM_POWERPC_BUGS_H
-
-/*
- */
-
-/*
- * This file is included by 'init/main.c' to check for
- * architecture-dependent bugs.
- */
-
-static inline void check_bugs(void) { }
-
-#endif	/* _ASM_POWERPC_BUGS_H */
arch/sh/Kconfig +1 -0
index 6904f4bdbf00..101b95f26a91 100644
@@ -7,6 +7,7 @@ config SUPERH
 	select ARCH_HAVE_CUSTOM_GPIO_H
 	select ARCH_HAVE_NMI_SAFE_CMPXCHG if (GUSA_RB || CPU_SH4A)
 	select ARCH_HAS_BINFMT_FLAT if !MMU
+	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_GIGANTIC_PAGE
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_PTE_SPECIAL
arch/sh/include/asm/bugs.h deleted +0 -74

74 lines not on this page · raw message

arch/sh/include/asm/processor.h +2 -0
index 3820d698846e..97af2d9b0269 100644
@@ -167,6 +167,8 @@ extern unsigned int instruction_size(unsigned int insn);
 #define instruction_size(insn)	(2)
 #endif
 
+void select_idle_routine(void);
+
 #endif /* __ASSEMBLY__ */
 
 #include <asm/processor_32.h>
arch/sh/kernel/idle.c +1 -0
index f59814983bd5..a80b2a5b25c7 100644
@@ -14,6 +14,7 @@
 #include <linux/irqflags.h>
 #include <linux/smp.h>
 #include <linux/atomic.h>
+#include <asm/processor.h>
 #include <asm/smp.h>
 #include <asm/bl_bit.h>
 
arch/sh/kernel/setup.c +55 -0

64 lines not on this page · raw message

arch/sparc/Kconfig +1 -0
index eff9116bf7be..1176f0de6a0f 100644
@@ -52,6 +52,7 @@ config SPARC
 config SPARC32
 	def_bool !64BIT
 	select ARCH_32BIT_OFF_T
+	select ARCH_HAS_CPU_FINALIZE_INIT if !SMP
 	select ARCH_HAS_SYNC_DMA_FOR_CPU
 	select GENERIC_ATOMIC64
 	select CLZ_TAB
arch/sparc/include/asm/bugs.h deleted +0 -18
deleted file mode 100644
index 02fa369b9c21..000000000000
@@ -1,18 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/* include/asm/bugs.h:  Sparc probes for various bugs.
- *
- * Copyright (C) 1996, 2007 David S. Miller ([email protected])
- */
-
-#ifdef CONFIG_SPARC32
-#include <asm/cpudata.h>
-#endif
-
-extern unsigned long loops_per_jiffy;
-
-static void __init check_bugs(void)
-{
-#if defined(CONFIG_SPARC32) && !defined(CONFIG_SMP)
-	cpu_data(0).udelay_val = loops_per_jiffy;
-#endif
-}
arch/sparc/kernel/setup_32.c +7 -0
index c8e0dd99f370..c9d1ba4f311b 100644
@@ -412,3 +412,10 @@ static int __init topology_init(void)
 }
 
 subsys_initcall(topology_init);
+
+#if defined(CONFIG_SPARC32) && !defined(CONFIG_SMP)
+void __init arch_cpu_finalize_init(void)
+{
+	cpu_data(0).udelay_val = loops_per_jiffy;
+}
+#endif
arch/um/Kconfig +1 -0
index c18b45f75d41..b0584453d2a0 100644
@@ -6,6 +6,7 @@ config UML
 	bool
 	default y
 	select ARCH_EPHEMERAL_INODES
+	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_KCOV
 	select ARCH_HAS_STRNCPY_FROM_USER
 	select ARCH_HAS_STRNLEN_USER
arch/um/include/asm/bugs.h deleted +0 -7
deleted file mode 100644
index 4473942a0839..000000000000
@@ -1,7 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __UM_BUGS_H
-#define __UM_BUGS_H
-
-void check_bugs(void);
-
-#endif
arch/um/kernel/um_arch.c +2 -1
index 4c8d2dc27084..748595b054c4 100644
@@ -3,6 +3,7 @@
  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  */
 
+#include <linux/cpu.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/mm.h>
@@ -423,7 +424,7 @@ void __init setup_arch(char **cmdline_p)
 	}
 }
 
-void __init check_bugs(void)
+void __init arch_cpu_finalize_init(void)
 {
 	arch_check_bugs();
 	os_check_bugs();
arch/x86/Kconfig +27 -0
index a08ce6360382..cfb1edd25437 100644
@@ -68,6 +68,7 @@ config X86
 	select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
 	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
 	select ARCH_HAS_CACHE_LINE_SIZE
+	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_DEBUG_VIRTUAL
 	select ARCH_HAS_DEBUG_VM_PGTABLE	if !X86_PAE
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
@@ -2456,6 +2457,13 @@ config CPU_IBRS_ENTRY
 	  This mitigates both spectre_v2 and retbleed at great cost to
 	  performance.
 
+config CPU_SRSO
+	bool "Mitigate speculative RAS overflow on AMD"
+	depends on CPU_SUP_AMD && X86_64 && RETHUNK
+	default y
+	help
+	  Enable the SRSO mitigation needed on AMD Zen1-4 machines.
+
 config SLS
 	bool "Mitigate Straight-Line-Speculation"
 	depends on CC_HAS_SLS && X86_64
@@ -2465,6 +2473,25 @@ config SLS
 	  against straight line speculation. The kernel image might be slightly
 	  larger.
 
+config GDS_FORCE_MITIGATION
+	bool "Force GDS Mitigation"
+	depends on CPU_SUP_INTEL
+	default n
+	help
+	  Gather Data Sampling (GDS) is a hardware vulnerability which allows
+	  unprivileged speculative access to data which was previously stored in
+	  vector registers.
+
+	  This option is equivalent to setting gather_data_sampling=force on the
+	  command line. The microcode mitigation is used if present, otherwise
+	  AVX is disabled as a mitigation. On affected systems that are missing
+	  the microcode any userspace code that unconditionally uses AVX will
+	  break with this option set.
+
+	  Setting this option on systems not vulnerable to GDS has no effect.
+
+	  If in doubt, say N.
+
 endif
 
 config ARCH_HAS_ADD_PAGES
arch/x86/include/asm/bugs.h +0 -2
index 92ae28389940..f25ca2d709d4 100644
@@ -4,8 +4,6 @@
 
 #include <asm/processor.h>
 
-extern void check_bugs(void);
-
 #if defined(CONFIG_CPU_SUP_INTEL) && defined(CONFIG_X86_32)
 int ppro_with_ram_bug(void);
 #else
arch/x86/include/asm/cpufeature.h +5 -2
index b0f206681fde..cc3f62f5d551 100644
@@ -32,6 +32,7 @@ enum cpuid_leafs
 	CPUID_8000_0007_EBX,
 	CPUID_7_EDX,
 	CPUID_8000_001F_EAX,
+	CPUID_8000_0021_EAX,
 };
 
 #ifdef CONFIG_X86_FEATURE_NAMES
@@ -91,8 +92,9 @@ extern const char * const x86_bug_flags[NBUGINTS*32];
 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 17, feature_bit) ||	\
 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 18, feature_bit) ||	\
 	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 19, feature_bit) ||	\
+	   CHECK_BIT_IN_MASK_WORD(REQUIRED_MASK, 20, feature_bit) ||	\
 	   REQUIRED_MASK_CHECK					  ||	\
-	   BUILD_BUG_ON_ZERO(NCAPINTS != 20))
+	   BUILD_BUG_ON_ZERO(NCAPINTS != 21))
 
 #define DISABLED_MASK_BIT_SET(feature_bit)				\
 	 ( CHECK_BIT_IN_MASK_WORD(DISABLED_MASK,  0, feature_bit) ||	\
@@ -115,8 +117,9 @@ extern const char * const x86_bug_flags[NBUGINTS*32];
 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 17, feature_bit) ||	\
 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 18, feature_bit) ||	\
 	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 19, feature_bit) ||	\
+	   CHECK_BIT_IN_MASK_WORD(DISABLED_MASK, 20, feature_bit) ||	\
 	   DISABLED_MASK_CHECK					  ||	\
-	   BUILD_BUG_ON_ZERO(NCAPINTS != 20))
+	   BUILD_BUG_ON_ZERO(NCAPINTS != 21))
 
 #define cpu_has(c, bit)							\
 	(__builtin_constant_p(bit) && REQUIRED_MASK_BIT_SET(bit) ? 1 :	\
arch/x86/include/asm/cpufeatures.h +13 -2
index e31c7e75d6b0..608ffc45fc0e 100644
@@ -13,8 +13,8 @@
 /*
  * Defines x86 CPU feature bits
  */
-#define NCAPINTS			20	   /* N 32-bit words worth of info */
-#define NBUGINTS			1	   /* N 32-bit bug flags */
+#define NCAPINTS			21	   /* N 32-bit words worth of info */
+#define NBUGINTS			2	   /* N 32-bit bug flags */
 
 /*
  * Note: If the comment begins with a quoted string, that string is used
@@ -306,6 +306,10 @@
 
 #define X86_FEATURE_MSR_TSX_CTRL	(11*32+20) /* "" MSR IA32_TSX_CTRL (Intel) implemented */
 
+#define X86_FEATURE_SRSO		(11*32+24) /* "" AMD BTB untrain RETs */
+#define X86_FEATURE_SRSO_ALIAS		(11*32+25) /* "" AMD BTB untrain RETs through aliasing */
+#define X86_FEATURE_IBPB_ON_VMEXIT	(11*32+26) /* "" Issue an IBPB only on VMEXIT */
+
 /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
 #define X86_FEATURE_AVX_VNNI		(12*32+ 4) /* AVX VNNI instructions */
 #define X86_FEATURE_AVX512_BF16		(12*32+ 5) /* AVX512 BFLOAT16 instructions */
@@ -412,6 +416,10 @@
 #define X86_FEATURE_SEV_ES		(19*32+ 3) /* AMD Secure Encrypted Virtualization - Encrypted State */
 #define X86_FEATURE_SME_COHERENT	(19*32+10) /* "" AMD hardware-enforced cache coherency */
 
+#define X86_FEATURE_SBPB		(20*32+27) /* "" Selective Branch Prediction Barrier */
+#define X86_FEATURE_IBPB_BRTYPE		(20*32+28) /* "" MSR_PRED_CMD[IBPB] flushes all branch type predictions */
+#define X86_FEATURE_SRSO_NO		(20*32+29) /* "" CPU is not affected by SRSO */
+
 /*
  * BUG word(s)
  */
@@ -453,5 +461,8 @@
 #define X86_BUG_RETBLEED		X86_BUG(27) /* CPU is affected by RETBleed */
 #define X86_BUG_EIBRS_PBRSB		X86_BUG(28) /* EIBRS is vulnerable to Post Barrier RSB Predictions */
 #define X86_BUG_SMT_RSB			X86_BUG(29) /* CPU is vulnerable to Cross-Thread Return Address Predictions */
+#define X86_BUG_GDS			X86_BUG(30) /* CPU is affected by Gather Data Sampling */
 
+/* BUG word 2 */
+#define X86_BUG_SRSO			X86_BUG(1*32 + 0) /* AMD SRSO bug */
 #endif /* _ASM_X86_CPUFEATURES_H */
arch/x86/include/asm/disabled-features.h +2 -1
index 834a3b6d81e1..99a12012c66e 100644
@@ -108,6 +108,7 @@
 #define DISABLED_MASK17	0
 #define DISABLED_MASK18	0
 #define DISABLED_MASK19	0
-#define DISABLED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 20)
+#define DISABLED_MASK20	0
+#define DISABLED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 21)
 
 #endif /* _ASM_X86_DISABLED_FEATURES_H */
arch/x86/include/asm/fpu/internal.h +1 -1
index ce6fc4f8d1d1..d4201fb2c46d 100644
@@ -43,7 +43,7 @@ extern void fpu_flush_thread(void);
 extern void fpu__init_cpu(void);
 extern void fpu__init_system_xstate(void);
 extern void fpu__init_cpu_xstate(void);
-extern void fpu__init_system(struct cpuinfo_x86 *c);
+extern void fpu__init_system(void);
 extern void fpu__init_check_bugs(void);
 extern void fpu__resume_cpu(void);
 
arch/x86/include/asm/mem_encrypt.h +4 -3
index 3fb9f5ebefa4..2356fdddd3e6 100644
@@ -47,14 +47,13 @@ int __init early_set_memory_encrypted(unsigned long vaddr, unsigned long size);
 
 void __init mem_encrypt_free_decrypted_mem(void);
 
-/* Architecture __weak replacement functions */
-void __init mem_encrypt_init(void);
-
 void __init sev_es_init_vc_handling(void);
 bool sme_active(void);
 bool sev_active(void);
 bool sev_es_active(void);
 
+void __init mem_encrypt_init(void);
+
 #define __bss_decrypted __section(".bss..decrypted")
 
 #else	/* !CONFIG_AMD_MEM_ENCRYPT */
@@ -87,6 +86,8 @@ early_set_memory_encrypted(unsigned long vaddr, unsigned long size) { return 0;
 
 static inline void mem_encrypt_free_decrypted_mem(void) { }
 
+static inline void mem_encrypt_init(void) { }
+
 #define __bss_decrypted
 
 #endif	/* CONFIG_AMD_MEM_ENCRYPT */
arch/x86/include/asm/msr-index.h +12 -0
index e78755ed82cf..91d8322af413 100644
@@ -60,6 +60,7 @@
 
 #define MSR_IA32_PRED_CMD		0x00000049 /* Prediction Command */
 #define PRED_CMD_IBPB			BIT(0)	   /* Indirect Branch Prediction Barrier */
+#define PRED_CMD_SBPB			BIT(7)	   /* Selective Branch Prediction Barrier */
 
 #define MSR_PPIN_CTL			0x0000004e
 #define MSR_PPIN			0x0000004f
@@ -156,6 +157,15 @@
 						 * Not susceptible to Post-Barrier
 						 * Return Stack Buffer Predictions.
 						 */
+#define ARCH_CAP_GDS_CTRL		BIT(25)	/*
+						 * CPU is vulnerable to Gather
+						 * Data Sampling (GDS) and
+						 * has controls for mitigation.
+						 */
+#define ARCH_CAP_GDS_NO			BIT(26)	/*
+						 * CPU is not vulnerable to Gather
+						 * Data Sampling (GDS).
+						 */
 
 #define MSR_IA32_FLUSH_CMD		0x0000010b
 #define L1D_FLUSH			BIT(0)	/*
@@ -174,6 +184,8 @@
 #define RNGDS_MITG_DIS			BIT(0)	/* SRBDS support */
 #define RTM_ALLOW			BIT(1)	/* TSX development mode */
 #define FB_CLEAR_DIS			BIT(3)	/* CPU Fill buffer clear disable */
+#define GDS_MITG_DIS			BIT(4)	/* Disable GDS mitigation */
+#define GDS_MITG_LOCKED			BIT(5)	/* GDS mitigation locked */
 
 #define MSR_IA32_SYSENTER_CS		0x00000174
 #define MSR_IA32_SYSENTER_ESP		0x00000175
arch/x86/include/asm/nospec-branch.h +13 -5
index 06c9f0eaa9ed..4a12dfdd317c 100644
@@ -112,7 +112,7 @@
  * eventually turn into it's own annotation.
  */
 .macro ANNOTATE_UNRET_END
-#ifdef CONFIG_DEBUG_ENTRY
+#if (defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_SRSO))
 	ANNOTATE_RETPOLINE_SAFE
 	nop
 #endif
@@ -173,12 +173,18 @@
  * where we have a stack but before any RET instruction.
  */
 .macro UNTRAIN_RET
-#if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY)
+#if defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_IBPB_ENTRY) || \
+	defined(CONFIG_CPU_SRSO)
 	ANNOTATE_UNRET_END
 	ALTERNATIVE_2 "",						\
 	              CALL_ZEN_UNTRAIN_RET, X86_FEATURE_UNRET,		\
 		      "call entry_ibpb", X86_FEATURE_ENTRY_IBPB
 #endif
+
+#ifdef CONFIG_CPU_SRSO
+	ALTERNATIVE_2 "", "call srso_untrain_ret", X86_FEATURE_SRSO, \
+			  "call srso_untrain_ret_alias", X86_FEATURE_SRSO_ALIAS
+#endif
 .endm
 
 #else /* __ASSEMBLY__ */
@@ -191,6 +197,8 @@
 
 extern void __x86_return_thunk(void);
 extern void zen_untrain_ret(void);
+extern void srso_untrain_ret(void);
+extern void srso_untrain_ret_alias(void);
 extern void entry_ibpb(void);
 
 #ifdef CONFIG_RETPOLINE
@@ -300,11 +308,11 @@ void alternative_msr_write(unsigned int msr, u64 val, unsigned int feature)
 		: "memory");
 }
 
+extern u64 x86_pred_cmd;
+
 static inline void indirect_branch_prediction_barrier(void)
 {
-	u64 val = PRED_CMD_IBPB;
-
-	alternative_msr_write(MSR_IA32_PRED_CMD, val, X86_FEATURE_USE_IBPB);
+	alternative_msr_write(MSR_IA32_PRED_CMD, x86_pred_cmd, X86_FEATURE_USE_IBPB);
 }
 
 /* The Intel SPEC CTRL MSR base value cache */
arch/x86/include/asm/processor.h +2 -0
index 3e3bd5b7d5db..747ccc2ae383 100644
@@ -803,9 +803,11 @@ extern u16 get_llc_id(unsigned int cpu);
 #ifdef CONFIG_CPU_SUP_AMD
 extern u32 amd_get_nodes_per_socket(void);
 extern u32 amd_get_highest_perf(void);
+extern bool cpu_has_ibpb_brtype_microcode(void);
 #else
 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
 static inline u32 amd_get_highest_perf(void)		{ return 0; }
+static inline bool cpu_has_ibpb_brtype_microcode(void)	{ return false; }
 #endif
 
 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
arch/x86/include/asm/required-features.h +2 -1
index b2d504f11937..9bf60a8b9e9c 100644
@@ -102,6 +102,7 @@
 #define REQUIRED_MASK17	0
 #define REQUIRED_MASK18	0
 #define REQUIRED_MASK19	0
-#define REQUIRED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 20)
+#define REQUIRED_MASK20	0
+#define REQUIRED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 21)
 
 #endif /* _ASM_X86_REQUIRED_FEATURES_H */
arch/x86/include/asm/sigframe.h +0 -2
index 5b1ed650b124..84eab2724875 100644
@@ -85,6 +85,4 @@ struct rt_sigframe_x32 {
 
 #endif /* CONFIG_X86_64 */
 
-void __init init_sigframe_size(void);
-
 #endif /* _ASM_X86_SIGFRAME_H */
arch/x86/kernel/cpu/amd.c +19 -0
index 3daceadf5d1f..1b90eb6ea503 100644
@@ -1270,6 +1270,25 @@ u32 amd_get_highest_perf(void)
 }
 EXPORT_SYMBOL_GPL(amd_get_highest_perf);
 
+bool cpu_has_ibpb_brtype_microcode(void)
+{
+	switch (boot_cpu_data.x86) {
+	/* Zen1/2 IBPB flushes branch type predictions too. */
+	case 0x17:
+		return boot_cpu_has(X86_FEATURE_AMD_IBPB);
+	case 0x19:
+		/* Poke the MSR bit on Zen3/4 to check its presence. */
+		if (!wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
+			setup_force_cpu_cap(X86_FEATURE_SBPB);
+			return true;
+		} else {
+			return false;
+		}
+	default:
+		return false;
+	}
+}
+
 static void zenbleed_check_cpu(void *unused)
 {
 	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
arch/x86/kernel/cpu/bugs.c +338 -50

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arch/x86/kernel/cpu/common.c +109 -17

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arch/x86/kernel/cpu/cpu.h +2 -0
index 7c9b5893c30a..d9aeb335002d 100644
@@ -79,9 +79,11 @@ extern void detect_ht(struct cpuinfo_x86 *c);
 extern void check_null_seg_clears_base(struct cpuinfo_x86 *c);
 
 unsigned int aperfmperf_get_khz(int cpu);
+void cpu_select_mitigations(void);
 
 extern void x86_spec_ctrl_setup_ap(void);
 extern void update_srbds_msr(void);
+extern void update_gds_msr(void);
 
 extern u64 x86_read_arch_cap_msr(void);
 
arch/x86/kernel/fpu/init.c +4 -4
index c949424a11c1..ddf65f1927e1 100644
@@ -49,7 +49,7 @@ void fpu__init_cpu(void)
 	fpu__init_cpu_xstate();
 }
 
-static bool fpu__probe_without_cpuid(void)
+static bool __init fpu__probe_without_cpuid(void)
 {
 	unsigned long cr0;
 	u16 fsw, fcw;
@@ -67,7 +67,7 @@ static bool fpu__probe_without_cpuid(void)
 	return fsw == 0 && (fcw & 0x103f) == 0x003f;
 }
 
-static void fpu__init_system_early_generic(struct cpuinfo_x86 *c)
+static void __init fpu__init_system_early_generic(void)
 {
 	if (!boot_cpu_has(X86_FEATURE_CPUID) &&
 	    !test_bit(X86_FEATURE_FPU, (unsigned long *)cpu_caps_cleared)) {
@@ -226,9 +226,9 @@ static void __init fpu__init_system_ctx_switch(void)
  * Called on the boot CPU once per system bootup, to set up the initial
  * FPU state that is later cloned into all processes:
  */
-void __init fpu__init_system(struct cpuinfo_x86 *c)
+void __init fpu__init_system(void)
 {
-	fpu__init_system_early_generic(c);
+	fpu__init_system_early_generic();
 
 	/*
 	 * The FPU has to be operational for some of the
arch/x86/kernel/signal.c +3 -1
index f4d21e470083..bf10340a9b71 100644
@@ -722,7 +722,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
 /* max_frame_size tells userspace the worst case signal stack size. */
 static unsigned long __ro_after_init max_frame_size;
 
-void __init init_sigframe_size(void)
+static int __init init_sigframe_size(void)
 {
 	max_frame_size = MAX_FRAME_SIGINFO_UCTXT_SIZE + MAX_FRAME_PADDING;
 
@@ -732,7 +732,9 @@ void __init init_sigframe_size(void)
 	max_frame_size = round_up(max_frame_size, FRAME_ALIGNMENT);
 
 	pr_info("max sigframe size: %lu\n", max_frame_size);
+	return 0;
 }
+early_initcall(init_sigframe_size);
 
 unsigned long get_sigframe_size(void)
 {
arch/x86/kernel/vmlinux.lds.S +31 -1
index c1efcd194ad7..50aaf0cd8f46 100644
@@ -133,7 +133,20 @@ SECTIONS
 		LOCK_TEXT
 		KPROBES_TEXT
 		ALIGN_ENTRY_TEXT_BEGIN
+#ifdef CONFIG_CPU_SRSO
+		*(.text.__x86.rethunk_untrain)
+#endif
+
 		ENTRY_TEXT
+
+#ifdef CONFIG_CPU_SRSO
+		/*
+		 * See the comment above srso_untrain_ret_alias()'s
+		 * definition.
+		 */
+		. = srso_untrain_ret_alias | (1 << 2) | (1 << 8) | (1 << 14) | (1 << 20);
+		*(.text.__x86.rethunk_safe)
+#endif
 		ALIGN_ENTRY_TEXT_END
 		SOFTIRQENTRY_TEXT
 		STATIC_CALL_TEXT
@@ -142,13 +155,15 @@ SECTIONS
 
 #ifdef CONFIG_RETPOLINE
 		__indirect_thunk_start = .;
-		*(.text.__x86.*)
+		*(.text.__x86.indirect_thunk)
+		*(.text.__x86.return_thunk)
 		__indirect_thunk_end = .;
 #endif
 	} :text =0xcccc
 
 	/* End of text section, which should occupy whole number of pages */
 	_etext = .;
+
 	. = ALIGN(PAGE_SIZE);
 
 	X86_ALIGN_RODATA_BEGIN
@@ -496,6 +511,21 @@ INIT_PER_CPU(irq_stack_backing_store);
            "fixed_percpu_data is not at start of per-cpu area");
 #endif
 
+ #ifdef CONFIG_RETHUNK
+. = ASSERT((__ret & 0x3f) == 0, "__ret not cacheline-aligned");
+. = ASSERT((srso_safe_ret & 0x3f) == 0, "srso_safe_ret not cacheline-aligned");
+#endif
+
+#ifdef CONFIG_CPU_SRSO
+/*
+ * GNU ld cannot do XOR so do: (A | B) - (A & B) in order to compute the XOR
+ * of the two function addresses:
+ */
+. = ASSERT(((srso_untrain_ret_alias | srso_safe_ret_alias) -
+		(srso_untrain_ret_alias & srso_safe_ret_alias)) == ((1 << 2) | (1 << 8) | (1 << 14) | (1 << 20)),
+		"SRSO function pair won't alias");
+#endif
+
 #endif /* CONFIG_X86_64 */
 
 #ifdef CONFIG_KEXEC_CORE
arch/x86/kvm/cpuid.c +3 -0
index 528437e3e2f3..b939b94d931f 100644
@@ -544,6 +544,9 @@ void kvm_set_cpu_caps(void)
 		F(PMM) | F(PMM_EN)
 	);
 
+	if (cpu_feature_enabled(X86_FEATURE_SRSO_NO))
+		kvm_cpu_cap_set(X86_FEATURE_SRSO_NO);
+
 	/*
 	 * Hide RDTSCP and RDPID if either feature is reported as supported but
 	 * probing MSR_TSC_AUX failed.  This is purely a sanity check and
arch/x86/kvm/reverse_cpuid.h +1 -0
index a19d473d0184..7eeade35a425 100644
@@ -48,6 +48,7 @@ static const struct cpuid_reg reverse_cpuid[] = {
 	[CPUID_7_1_EAX]       = {         7, 1, CPUID_EAX},
 	[CPUID_12_EAX]        = {0x00000012, 0, CPUID_EAX},
 	[CPUID_8000_001F_EAX] = {0x8000001f, 0, CPUID_EAX},
+	[CPUID_8000_0021_EAX] = {0x80000021, 0, CPUID_EAX},
 };
 
 /*
arch/x86/kvm/svm/svm.c +3 -1
index 302a4669c5a1..d63c3843e493 100644
@@ -1489,7 +1489,9 @@ static void svm_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
 	if (sd->current_vmcb != svm->vmcb) {
 		sd->current_vmcb = svm->vmcb;
-		indirect_branch_prediction_barrier();
+
+		if (!cpu_feature_enabled(X86_FEATURE_IBPB_ON_VMEXIT))
+			indirect_branch_prediction_barrier();
 	}
 	if (kvm_vcpu_apicv_active(vcpu))
 		avic_vcpu_load(vcpu, cpu);
arch/x86/kvm/svm/vmenter.S +3 -0
index 723f8534986c..f96060855522 100644
@@ -119,6 +119,9 @@ SYM_FUNC_START(__svm_vcpu_run)
 	 */
 	UNTRAIN_RET
 
+	/* SRSO */
+	ALTERNATIVE "", "call entry_ibpb", X86_FEATURE_IBPB_ON_VMEXIT
+
 	/*
 	 * Clear all general purpose registers except RSP and RAX to prevent
 	 * speculative use of the guest's values, even those that are reloaded
arch/x86/kvm/x86.c +6 -1
index 285ba12be8ce..2686c4dcdb1a 100644
@@ -303,6 +303,8 @@ static struct kmem_cache *x86_fpu_cache;
 
 static struct kmem_cache *x86_emulator_cache;
 
+extern bool gds_ucode_mitigated(void);
+
 /*
  * When called, it means the previous get/set msr reached an invalid msr.
  * Return true if we want to ignore/silent this failed msr access.
@@ -1498,7 +1500,7 @@ static unsigned int num_msr_based_features;
 	 ARCH_CAP_SKIP_VMENTRY_L1DFLUSH | ARCH_CAP_SSB_NO | ARCH_CAP_MDS_NO | \
 	 ARCH_CAP_PSCHANGE_MC_NO | ARCH_CAP_TSX_CTRL_MSR | ARCH_CAP_TAA_NO | \
 	 ARCH_CAP_SBDR_SSDP_NO | ARCH_CAP_FBSDP_NO | ARCH_CAP_PSDP_NO | \
-	 ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO)
+	 ARCH_CAP_FB_CLEAR | ARCH_CAP_RRSBA | ARCH_CAP_PBRSB_NO | ARCH_CAP_GDS_NO)
 
 static u64 kvm_get_arch_capabilities(void)
 {
@@ -1555,6 +1557,9 @@ static u64 kvm_get_arch_capabilities(void)
 		 */
 	}
 
+	if (!boot_cpu_has_bug(X86_BUG_GDS) || gds_ucode_mitigated())
+		data |= ARCH_CAP_GDS_NO;
+
 	return data;
 }
 
arch/x86/lib/retpoline.S +77 -4

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arch/x86/mm/init.c +5 -1
index 34a08f6a528e..56d5ab70bfa1 100644
@@ -27,6 +27,7 @@
 #include <asm/pti.h>
 #include <asm/text-patching.h>
 #include <asm/memtype.h>
+#include <asm/paravirt.h>
 
 /*
  * We need to define the tracepoints somewhere, and tlb.c
@@ -822,9 +823,12 @@ void __init poking_init(void)
 	spinlock_t *ptl;
 	pte_t *ptep;
 
-	poking_mm = copy_init_mm();
+	poking_mm = mm_alloc();
 	BUG_ON(!poking_mm);
 
+	/* Xen PV guests need the PGD to be pinned. */
+	paravirt_arch_dup_mmap(NULL, poking_mm);
+
 	/*
 	 * Randomize the poking address, but make sure that the following page
 	 * will be mapped at the same PMD. We need 2 pages, so find space for 3,
arch/x86/xen/smp_pv.c +2 -0
index b47b5111397a..a1f974309b1c 100644
@@ -30,6 +30,7 @@
 #include <asm/desc.h>
 #include <asm/cpu.h>
 #include <asm/io_apic.h>
+#include <asm/fpu/internal.h>
 
 #include <xen/interface/xen.h>
 #include <xen/interface/vcpu.h>
@@ -63,6 +64,7 @@ static void cpu_bringup(void)
 
 	cr4_init();
 	cpu_init();
+	fpu__init_cpu();
 	touch_softlockup_watchdog();
 
 	/* PVH runs in ring 0 and allows us to do native syscalls. Yay! */
arch/xtensa/include/asm/bugs.h deleted +0 -18
deleted file mode 100644
index 69b29d198249..000000000000
@@ -1,18 +0,0 @@
-/*
- * include/asm-xtensa/bugs.h
- *
- * This is included by init/main.c to check for architecture-dependent bugs.
- *
- * Xtensa processors don't have any bugs.  :)
- *
- * This file is subject to the terms and conditions of the GNU General
- * Public License.  See the file "COPYING" in the main directory of
- * this archive for more details.
- */
-
-#ifndef _XTENSA_BUGS_H
-#define _XTENSA_BUGS_H
-
-static void check_bugs(void) { }
-
-#endif /* _XTENSA_BUGS_H */
drivers/base/cpu.c +16 -0
index 450dca235a2f..46430cf2401e 100644
@@ -577,6 +577,18 @@ ssize_t __weak cpu_show_retbleed(struct device *dev,
 	return sysfs_emit(buf, "Not affected\n");
 }
 
+ssize_t __weak cpu_show_gds(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "Not affected\n");
+}
+
+ssize_t __weak cpu_show_spec_rstack_overflow(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);
@@ -588,6 +600,8 @@ 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 DEVICE_ATTR(retbleed, 0444, cpu_show_retbleed, NULL);
+static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL);
+static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NULL);
 
 static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_meltdown.attr,
@@ -601,6 +615,8 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_srbds.attr,
 	&dev_attr_mmio_stale_data.attr,
 	&dev_attr_retbleed.attr,
+	&dev_attr_gather_data_sampling.attr,
+	&dev_attr_spec_rstack_overflow.attr,
 	NULL
 };
 
drivers/net/xen-netback/netback.c +10 -5
index 63118b56c528..5017033c705a 100644
@@ -396,7 +396,7 @@ static void xenvif_get_requests(struct xenvif_queue *queue,
 	struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops;
 	struct xen_netif_tx_request *txp = first;
 
-	nr_slots = shinfo->nr_frags + 1;
+	nr_slots = shinfo->nr_frags + frag_overflow + 1;
 
 	copy_count(skb) = 0;
 	XENVIF_TX_CB(skb)->split_mask = 0;
@@ -462,8 +462,8 @@ static void xenvif_get_requests(struct xenvif_queue *queue,
 		}
 	}
 
-	for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
-	     shinfo->nr_frags++, gop++) {
+	for (shinfo->nr_frags = 0; nr_slots > 0 && shinfo->nr_frags < MAX_SKB_FRAGS;
+	     shinfo->nr_frags++, gop++, nr_slots--) {
 		index = pending_index(queue->pending_cons++);
 		pending_idx = queue->pending_ring[index];
 		xenvif_tx_create_map_op(queue, pending_idx, txp,
@@ -476,12 +476,12 @@ static void xenvif_get_requests(struct xenvif_queue *queue,
 			txp++;
 	}
 
-	if (frag_overflow) {
+	if (nr_slots > 0) {
 
 		shinfo = skb_shinfo(nskb);
 		frags = shinfo->frags;
 
-		for (shinfo->nr_frags = 0; shinfo->nr_frags < frag_overflow;
+		for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
 		     shinfo->nr_frags++, txp++, gop++) {
 			index = pending_index(queue->pending_cons++);
 			pending_idx = queue->pending_ring[index];
@@ -492,6 +492,11 @@ static void xenvif_get_requests(struct xenvif_queue *queue,
 		}
 
 		skb_shinfo(skb)->frag_list = nskb;
+	} else if (nskb) {
+		/* A frag_list skb was allocated but it is no longer needed
+		 * because enough slots were converted to copy ops above.
+		 */
+		kfree_skb(nskb);
 	}
 
 	(*copy_ops) = cop - queue->tx_copy_ops;
include/asm-generic/bugs.h deleted +0 -11
deleted file mode 100644
index 69021830f078..000000000000
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef __ASM_GENERIC_BUGS_H
-#define __ASM_GENERIC_BUGS_H
-/*
- * This file is included by 'init/main.c' to check for
- * architecture-dependent bugs.
- */
-
-static inline void check_bugs(void) { }
-
-#endif	/* __ASM_GENERIC_BUGS_H */
include/linux/cpu.h +8 -0
index 6102a21a01d9..d4c860de9a6a 100644
@@ -70,6 +70,8 @@ extern ssize_t cpu_show_mmio_stale_data(struct device *dev,
 					char *buf);
 extern ssize_t cpu_show_retbleed(struct device *dev,
 				 struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_spec_rstack_overflow(struct device *dev,
+					     struct device_attribute *attr, char *buf);
 
 extern __printf(4, 5)
 struct device *cpu_device_create(struct device *parent, void *drvdata,
@@ -187,6 +189,12 @@ void arch_cpu_idle_enter(void);
 void arch_cpu_idle_exit(void);
 void arch_cpu_idle_dead(void);
 
+#ifdef CONFIG_ARCH_HAS_CPU_FINALIZE_INIT
+void arch_cpu_finalize_init(void);
+#else
+static inline void arch_cpu_finalize_init(void) { }
+#endif
+
 int cpu_report_state(int cpu);
 int cpu_check_up_prepare(int cpu);
 void cpu_set_state_online(int cpu);
include/linux/sched/task.h +1 -1
index d351f1b362ef..d23977e9035d 100644
@@ -61,6 +61,7 @@ extern void sched_dead(struct task_struct *p);
 void __noreturn do_task_dead(void);
 void __noreturn make_task_dead(int signr);
 
+extern void mm_cache_init(void);
 extern void proc_caches_init(void);
 
 extern void fork_init(void);
@@ -87,7 +88,6 @@ extern void exit_itimers(struct task_struct *);
 extern pid_t kernel_clone(struct kernel_clone_args *kargs);
 struct task_struct *create_io_thread(int (*fn)(void *), void *arg, int node);
 struct task_struct *fork_idle(int);
-struct mm_struct *copy_init_mm(void);
 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 extern long kernel_wait4(pid_t, int __user *, int, struct rusage *);
 int kernel_wait(pid_t pid, int *stat);
init/main.c +5 -16
index 649d9e4201a8..63737af8de51 100644
@@ -96,7 +96,6 @@
 #include <linux/cache.h>
 #include <linux/rodata_test.h>
 #include <linux/jump_label.h>
-#include <linux/mem_encrypt.h>
 #include <linux/kcsan.h>
 #include <linux/init_syscalls.h>
 #include <linux/stackdepot.h>
@@ -104,7 +103,6 @@
 #include <net/net_namespace.h>
 
 #include <asm/io.h>
-#include <asm/bugs.h>
 #include <asm/setup.h>
 #include <asm/sections.h>
 #include <asm/cacheflush.h>
@@ -788,8 +786,6 @@ void __init __weak thread_stack_cache_init(void)
 }
 #endif
 
-void __init __weak mem_encrypt_init(void) { }
-
 void __init __weak poking_init(void) { }
 
 void __init __weak pgtable_cache_init(void) { }
@@ -859,6 +855,7 @@ static void __init mm_init(void)
 	init_espfix_bsp();
 	/* Should be run after espfix64 is set up. */
 	pti_init();
+	mm_cache_init();
 }
 
 #ifdef CONFIG_HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
@@ -991,7 +988,7 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 	sort_main_extable();
 	trap_init();
 	mm_init();
-
+	poking_init();
 	ftrace_init();
 
 	/* trace_printk can be enabled here */
@@ -1083,14 +1080,6 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 	 */
 	locking_selftest();
 
-	/*
-	 * This needs to be called before any devices perform DMA
-	 * operations that might use the SWIOTLB bounce buffers. It will
-	 * mark the bounce buffers as decrypted so that their usage will
-	 * not cause "plain-text" data to be decrypted when accessed.
-	 */
-	mem_encrypt_init();
-
 #ifdef CONFIG_BLK_DEV_INITRD
 	if (initrd_start && !initrd_below_start_ok &&
 	    page_to_pfn(virt_to_page((void *)initrd_start)) < min_low_pfn) {
@@ -1107,6 +1096,9 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 		late_time_init();
 	sched_clock_init();
 	calibrate_delay();
+
+	arch_cpu_finalize_init();
+
 	pid_idr_init();
 	anon_vma_init();
 #ifdef CONFIG_X86
@@ -1133,9 +1125,6 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void)
 	taskstats_init_early();
 	delayacct_init();
 
-	poking_init();
-	check_bugs();
-
 	acpi_subsystem_init();
 	arch_post_acpi_subsys_init();
 	kcsan_init();
kernel/fork.c +18 -19
index 1906230a000e..ace0717c71e2 100644
@@ -2522,11 +2522,6 @@ struct task_struct * __init fork_idle(int cpu)
 	return task;
 }
 
-struct mm_struct *copy_init_mm(void)
-{
-	return dup_mm(NULL, &init_mm);
-}
-
 /*
  * This is like kernel_clone(), but shaved down and tailored to just
  * creating io_uring workers. It returns a created task, or an error pointer.
@@ -2921,10 +2916,27 @@ static void sighand_ctor(void *data)
 	init_waitqueue_head(&sighand->signalfd_wqh);
 }
 
-void __init proc_caches_init(void)
+void __init mm_cache_init(void)
 {
 	unsigned int mm_size;
 
+	/*
+	 * The mm_cpumask is located at the end of mm_struct, and is
+	 * dynamically sized based on the maximum CPU number this system
+	 * can have, taking hotplug into account (nr_cpu_ids).
+	 */
+	mm_size = sizeof(struct mm_struct) + cpumask_size();
+
+	mm_cachep = kmem_cache_create_usercopy("mm_struct",
+			mm_size, ARCH_MIN_MMSTRUCT_ALIGN,
+			SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT,
+			offsetof(struct mm_struct, saved_auxv),
+			sizeof_field(struct mm_struct, saved_auxv),
+			NULL);
+}
+
+void __init proc_caches_init(void)
+{
 	sighand_cachep = kmem_cache_create("sighand_cache",
 			sizeof(struct sighand_struct), 0,
 			SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_TYPESAFE_BY_RCU|
@@ -2942,19 +2954,6 @@ void __init proc_caches_init(void)
 			SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT,
 			NULL);
 
-	/*
-	 * The mm_cpumask is located at the end of mm_struct, and is
-	 * dynamically sized based on the maximum CPU number this system
-	 * can have, taking hotplug into account (nr_cpu_ids).
-	 */
-	mm_size = sizeof(struct mm_struct) + cpumask_size();
-
-	mm_cachep = kmem_cache_create_usercopy("mm_struct",
-			mm_size, ARCH_MIN_MMSTRUCT_ALIGN,
-			SLAB_HWCACHE_ALIGN|SLAB_PANIC|SLAB_ACCOUNT,
-			offsetof(struct mm_struct, saved_auxv),
-			sizeof_field(struct mm_struct, saved_auxv),
-			NULL);
 	vm_area_cachep = KMEM_CACHE(vm_area_struct, SLAB_PANIC|SLAB_ACCOUNT);
 	mmap_init();
 	nsproxy_cache_init();
tools/arch/x86/include/asm/cpufeatures.h +1 -1
index bcaedfe60572..861451839cf2 100644
@@ -14,7 +14,7 @@
  * Defines x86 CPU feature bits
  */
 #define NCAPINTS			20	   /* N 32-bit words worth of info */
-#define NBUGINTS			1	   /* N 32-bit bug flags */
+#define NBUGINTS			2	   /* N 32-bit bug flags */
 
 /*
  * Note: If the comment begins with a quoted string, that string is used
tools/objtool/arch/x86/decode.c +4 -1
index f62db0e006e9..cf8ea3594125 100644
@@ -725,5 +725,8 @@ bool arch_is_retpoline(struct symbol *sym)
 
 bool arch_is_rethunk(struct symbol *sym)
 {
-	return !strcmp(sym->name, "__x86_return_thunk");
+	return !strcmp(sym->name, "__x86_return_thunk") ||
+	       !strcmp(sym->name, "srso_untrain_ret") ||
+	       !strcmp(sym->name, "srso_safe_ret") ||
+	       !strcmp(sym->name, "__ret");
 }