diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0086-retpoline-Introduce-start-end-markers-of-indirect-th.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0086-retpoline-Introduce-start-end-markers-of-indirect-th.patch | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0086-retpoline-Introduce-start-end-markers-of-indirect-th.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0086-retpoline-Introduce-start-end-markers-of-indirect-th.patch new file mode 100644 index 00000000..9beafd46 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0086-retpoline-Introduce-start-end-markers-of-indirect-th.patch @@ -0,0 +1,78 @@ +From d21c5cadc96cf42c7791840b421afc1a018e6a87 Mon Sep 17 00:00:00 2001 +From: Masami Hiramatsu <mhiramat@kernel.org> +Date: Fri, 19 Jan 2018 01:14:21 +0900 +Subject: [PATCH 086/103] retpoline: Introduce start/end markers of indirect + thunk + +commit 736e80a4213e9bbce40a7c050337047128b472ac upstream. + +Introduce start/end markers of __x86_indirect_thunk_* functions. +To make it easy, consolidate .text.__x86.indirect_thunk.* sections +to one .text.__x86.indirect_thunk section and put it in the +end of kernel text section and adds __indirect_thunk_start/end +so that other subsystem (e.g. kprobes) can identify it. + +Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Acked-by: David Woodhouse <dwmw@amazon.co.uk> +Cc: Andi Kleen <ak@linux.intel.com> +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> +Cc: Arjan van de Ven <arjan@linux.intel.com> +Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org> +Link: https://lkml.kernel.org/r/151629206178.10241.6828804696410044771.stgit@devbox +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/x86/include/asm/nospec-branch.h | 3 +++ + arch/x86/kernel/vmlinux.lds.S | 7 +++++++ + arch/x86/lib/retpoline.S | 2 +- + 3 files changed, 11 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h +index 7b45d84..19ba5ad 100644 +--- a/arch/x86/include/asm/nospec-branch.h ++++ b/arch/x86/include/asm/nospec-branch.h +@@ -194,6 +194,9 @@ enum spectre_v2_mitigation { + SPECTRE_V2_IBRS, + }; + ++extern char __indirect_thunk_start[]; ++extern char __indirect_thunk_end[]; ++ + /* + * On VMEXIT we must ensure that no RSB predictions learned in the guest + * can be followed in the host, by overwriting the RSB completely. Both +diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S +index dbf67f6..c7194e9 100644 +--- a/arch/x86/kernel/vmlinux.lds.S ++++ b/arch/x86/kernel/vmlinux.lds.S +@@ -105,6 +105,13 @@ SECTIONS + SOFTIRQENTRY_TEXT + *(.fixup) + *(.gnu.warning) ++ ++#ifdef CONFIG_RETPOLINE ++ __indirect_thunk_start = .; ++ *(.text.__x86.indirect_thunk) ++ __indirect_thunk_end = .; ++#endif ++ + /* End of text section */ + _etext = .; + } :text = 0x9090 +diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S +index cb45c6c..d3415dc 100644 +--- a/arch/x86/lib/retpoline.S ++++ b/arch/x86/lib/retpoline.S +@@ -9,7 +9,7 @@ + #include <asm/nospec-branch.h> + + .macro THUNK reg +- .section .text.__x86.indirect_thunk.\reg ++ .section .text.__x86.indirect_thunk + + ENTRY(__x86_indirect_thunk_\reg) + CFI_STARTPROC +-- +2.7.4 + |