diff options
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.patch | 102 |
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 - |