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Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Add-basic-IBPB-Indirect-Branch-Predi.patch')
-rw-r--r--common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Add-basic-IBPB-Indirect-Branch-Predi.patch102
1 files changed, 0 insertions, 102 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Add-basic-IBPB-Indirect-Branch-Predi.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Add-basic-IBPB-Indirect-Branch-Predi.patch
deleted file mode 100644
index ed57dfd2..00000000
--- a/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Add-basic-IBPB-Indirect-Branch-Predi.patch
+++ /dev/null
@@ -1,102 +0,0 @@
-From 8d91a1887b4fccf06f4077529dc167a52590b348 Mon Sep 17 00:00:00 2001
-From: David Woodhouse <dwmw@amazon.co.uk>
-Date: Thu, 25 Jan 2018 16:14:15 +0000
-Subject: [PATCH 14/42] x86/speculation: Add basic IBPB (Indirect Branch
- Prediction Barrier) support
-
-(cherry picked from commit 20ffa1caecca4db8f79fe665acdeaa5af815a24d)
-
-Expose indirect_branch_prediction_barrier() for use in subsequent patches.
-
-[ tglx: Add IBPB status to spectre_v2 sysfs file ]
-
-Co-developed-by: KarimAllah Ahmed <karahmed@amazon.de>
-Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
-Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
-Cc: gnomes@lxorguk.ukuu.org.uk
-Cc: ak@linux.intel.com
-Cc: ashok.raj@intel.com
-Cc: dave.hansen@intel.com
-Cc: arjan@linux.intel.com
-Cc: torvalds@linux-foundation.org
-Cc: peterz@infradead.org
-Cc: bp@alien8.de
-Cc: pbonzini@redhat.com
-Cc: tim.c.chen@linux.intel.com
-Cc: gregkh@linux-foundation.org
-Link: https://lkml.kernel.org/r/1516896855-7642-8-git-send-email-dwmw@amazon.co.uk
-Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
----
- arch/x86/include/asm/cpufeatures.h | 2 ++
- arch/x86/include/asm/nospec-branch.h | 13 +++++++++++++
- arch/x86/kernel/cpu/bugs.c | 10 +++++++++-
- 3 files changed, 24 insertions(+), 1 deletion(-)
-
-diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
-index c4d03e7..3901545 100644
---- a/arch/x86/include/asm/cpufeatures.h
-+++ b/arch/x86/include/asm/cpufeatures.h
-@@ -202,6 +202,8 @@
- /* Because the ALTERNATIVE scheme is for members of the X86_FEATURE club... */
- #define X86_FEATURE_KAISER ( 7*32+31) /* CONFIG_PAGE_TABLE_ISOLATION w/o nokaiser */
-
-+#define X86_FEATURE_IBPB ( 7*32+21) /* Indirect Branch Prediction Barrier enabled*/
-+
- /* Virtualization flags: Linux defined, word 8 */
- #define X86_FEATURE_TPR_SHADOW ( 8*32+ 0) /* Intel TPR Shadow */
- #define X86_FEATURE_VNMI ( 8*32+ 1) /* Intel Virtual NMI */
-diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
-index 4ad4108..34e384c 100644
---- a/arch/x86/include/asm/nospec-branch.h
-+++ b/arch/x86/include/asm/nospec-branch.h
-@@ -218,5 +218,18 @@ static inline void vmexit_fill_RSB(void)
- #endif
- }
-
-+static inline void indirect_branch_prediction_barrier(void)
-+{
-+ asm volatile(ALTERNATIVE("",
-+ "movl %[msr], %%ecx\n\t"
-+ "movl %[val], %%eax\n\t"
-+ "movl $0, %%edx\n\t"
-+ "wrmsr",
-+ X86_FEATURE_IBPB)
-+ : : [msr] "i" (MSR_IA32_PRED_CMD),
-+ [val] "i" (PRED_CMD_IBPB)
-+ : "eax", "ecx", "edx", "memory");
-+}
-+
- #endif /* __ASSEMBLY__ */
- #endif /* __NOSPEC_BRANCH_H__ */
-diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
-index 4cea7d4..1c4b39d 100644
---- a/arch/x86/kernel/cpu/bugs.c
-+++ b/arch/x86/kernel/cpu/bugs.c
-@@ -262,6 +262,13 @@ static void __init spectre_v2_select_mitigation(void)
- setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW);
- pr_info("Filling RSB on context switch\n");
- }
-+
-+ /* Initialize Indirect Branch Prediction Barrier if supported */
-+ if (boot_cpu_has(X86_FEATURE_SPEC_CTRL) ||
-+ boot_cpu_has(X86_FEATURE_AMD_PRED_CMD)) {
-+ setup_force_cpu_cap(X86_FEATURE_IBPB);
-+ pr_info("Enabling Indirect Branch Prediction Barrier\n");
-+ }
- }
-
- #undef pr_fmt
-@@ -291,7 +298,8 @@ ssize_t cpu_show_spectre_v2(struct device *dev,
- if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2))
- return sprintf(buf, "Not affected\n");
-
-- return sprintf(buf, "%s%s\n", spectre_v2_strings[spectre_v2_enabled],
-+ return sprintf(buf, "%s%s%s\n", spectre_v2_strings[spectre_v2_enabled],
-+ boot_cpu_has(X86_FEATURE_IBPB) ? ", IPBP" : "",
- spectre_v2_bad_module ? " - vulnerable module loaded" : "");
- }
- #endif
---
-2.7.4
-