diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-speculation-Clean-up-various-Spectre-related-det.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-speculation-Clean-up-various-Spectre-related-det.patch | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-speculation-Clean-up-various-Spectre-related-det.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-speculation-Clean-up-various-Spectre-related-det.patch new file mode 100644 index 00000000..e6531584 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0005-x86-speculation-Clean-up-various-Spectre-related-det.patch @@ -0,0 +1,148 @@ +From 891112052277801e900b37496ca8c260a5e7e7e1 Mon Sep 17 00:00:00 2001 +From: Ingo Molnar <mingo@kernel.org> +Date: Tue, 13 Feb 2018 09:03:08 +0100 +Subject: [PATCH 05/12] x86/speculation: Clean up various Spectre related + details + +commit 21e433bdb95bdf3aa48226fd3d33af608437f293 upstream. + +Harmonize all the Spectre messages so that a: + + dmesg | grep -i spectre + +... gives us most Spectre related kernel boot messages. + +Also fix a few other details: + + - clarify a comment about firmware speculation control + + - s/KPTI/PTI + + - remove various line-breaks that made the code uglier + +Acked-by: David Woodhouse <dwmw@amazon.co.uk> +Cc: Andy Lutomirski <luto@kernel.org> +Cc: Arjan van de Ven <arjan@linux.intel.com> +Cc: Borislav Petkov <bp@alien8.de> +Cc: Dan Williams <dan.j.williams@intel.com> +Cc: Dave Hansen <dave.hansen@linux.intel.com> +Cc: David Woodhouse <dwmw2@infradead.org> +Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +Cc: Josh Poimboeuf <jpoimboe@redhat.com> +Cc: Linus Torvalds <torvalds@linux-foundation.org> +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: Thomas Gleixner <tglx@linutronix.de> +Cc: linux-kernel@vger.kernel.org +Signed-off-by: Ingo Molnar <mingo@kernel.org> +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/x86/kernel/cpu/bugs.c | 28 +++++++++++----------------- + 1 file changed, 11 insertions(+), 17 deletions(-) + +diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c +index 957ad44..b83e0c9 100644 +--- a/arch/x86/kernel/cpu/bugs.c ++++ b/arch/x86/kernel/cpu/bugs.c +@@ -161,8 +161,7 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void) + if (cmdline_find_option_bool(boot_command_line, "nospectre_v2")) + return SPECTRE_V2_CMD_NONE; + else { +- ret = cmdline_find_option(boot_command_line, "spectre_v2", arg, +- sizeof(arg)); ++ ret = cmdline_find_option(boot_command_line, "spectre_v2", arg, sizeof(arg)); + if (ret < 0) + return SPECTRE_V2_CMD_AUTO; + +@@ -174,8 +173,7 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void) + } + + if (i >= ARRAY_SIZE(mitigation_options)) { +- pr_err("unknown option (%s). Switching to AUTO select\n", +- mitigation_options[i].option); ++ pr_err("unknown option (%s). Switching to AUTO select\n", mitigation_options[i].option); + return SPECTRE_V2_CMD_AUTO; + } + } +@@ -184,8 +182,7 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void) + cmd == SPECTRE_V2_CMD_RETPOLINE_AMD || + cmd == SPECTRE_V2_CMD_RETPOLINE_GENERIC) && + !IS_ENABLED(CONFIG_RETPOLINE)) { +- pr_err("%s selected but not compiled in. Switching to AUTO select\n", +- mitigation_options[i].option); ++ pr_err("%s selected but not compiled in. Switching to AUTO select\n", mitigation_options[i].option); + return SPECTRE_V2_CMD_AUTO; + } + +@@ -255,14 +252,14 @@ static void __init spectre_v2_select_mitigation(void) + goto retpoline_auto; + break; + } +- pr_err("kernel not compiled with retpoline; no mitigation available!"); ++ pr_err("Spectre mitigation: kernel not compiled with retpoline; no mitigation available!"); + return; + + retpoline_auto: + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) { + retpoline_amd: + if (!boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) { +- pr_err("LFENCE not serializing. Switching to generic retpoline\n"); ++ pr_err("Spectre mitigation: LFENCE not serializing, switching to generic retpoline\n"); + goto retpoline_generic; + } + mode = retp_compiler() ? SPECTRE_V2_RETPOLINE_AMD : +@@ -280,7 +277,7 @@ static void __init spectre_v2_select_mitigation(void) + pr_info("%s\n", spectre_v2_strings[mode]); + + /* +- * If neither SMEP or KPTI are available, there is a risk of ++ * If neither SMEP nor PTI are available, there is a risk of + * hitting userspace addresses in the RSB after a context switch + * from a shallow call stack to a deeper one. To prevent this fill + * the entire RSB, even when using IBRS. +@@ -294,21 +291,20 @@ static void __init spectre_v2_select_mitigation(void) + if ((!boot_cpu_has(X86_FEATURE_KAISER) && + !boot_cpu_has(X86_FEATURE_SMEP)) || is_skylake_era()) { + setup_force_cpu_cap(X86_FEATURE_RSB_CTXSW); +- pr_info("Filling RSB on context switch\n"); ++ pr_info("Spectre v2 mitigation: Filling RSB on context switch\n"); + } + + /* Initialize Indirect Branch Prediction Barrier if supported */ + if (boot_cpu_has(X86_FEATURE_IBPB)) { + setup_force_cpu_cap(X86_FEATURE_USE_IBPB); +- pr_info("Enabling Indirect Branch Prediction Barrier\n"); ++ pr_info("Spectre v2 mitigation: Enabling Indirect Branch Prediction Barrier\n"); + } + } + + #undef pr_fmt + + #ifdef CONFIG_SYSFS +-ssize_t cpu_show_meltdown(struct device *dev, +- struct device_attribute *attr, char *buf) ++ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, char *buf) + { + if (!boot_cpu_has_bug(X86_BUG_CPU_MELTDOWN)) + return sprintf(buf, "Not affected\n"); +@@ -317,16 +313,14 @@ ssize_t cpu_show_meltdown(struct device *dev, + return sprintf(buf, "Vulnerable\n"); + } + +-ssize_t cpu_show_spectre_v1(struct device *dev, +- struct device_attribute *attr, char *buf) ++ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf) + { + if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1)) + return sprintf(buf, "Not affected\n"); + return sprintf(buf, "Mitigation: __user pointer sanitization\n"); + } + +-ssize_t cpu_show_spectre_v2(struct device *dev, +- struct device_attribute *attr, char *buf) ++ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf) + { + if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V2)) + return sprintf(buf, "Not affected\n"); +-- +2.7.4 + |