diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0085-x86-mce-Make-machine-check-speculation-protected.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0085-x86-mce-Make-machine-check-speculation-protected.patch | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0085-x86-mce-Make-machine-check-speculation-protected.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0085-x86-mce-Make-machine-check-speculation-protected.patch new file mode 100644 index 00000000..b1ad4a54 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0085-x86-mce-Make-machine-check-speculation-protected.patch @@ -0,0 +1,69 @@ +From 579259fc2702d354fa172e6e16d26c740a3d4421 Mon Sep 17 00:00:00 2001 +From: Thomas Gleixner <tglx@linutronix.de> +Date: Thu, 18 Jan 2018 16:28:26 +0100 +Subject: [PATCH 085/103] x86/mce: Make machine check speculation protected + +commit 6f41c34d69eb005e7848716bbcafc979b35037d5 upstream. + +The machine check idtentry uses an indirect branch directly from the low +level code. This evades the speculation protection. + +Replace it by a direct call into C code and issue the indirect call there +so the compiler can apply the proper speculation protection. + +Signed-off-by: Thomas Gleixner <tglx@linutronix.de> +Reviewed-by:Borislav Petkov <bp@alien8.de> +Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> +Niced-by: Peter Zijlstra <peterz@infradead.org> +Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801181626290.1847@nanos +Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> +--- + arch/x86/entry/entry_64.S | 2 +- + arch/x86/include/asm/traps.h | 1 + + arch/x86/kernel/cpu/mcheck/mce.c | 5 +++++ + 3 files changed, 7 insertions(+), 1 deletion(-) + +diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S +index eff47f5..16146eb 100644 +--- a/arch/x86/entry/entry_64.S ++++ b/arch/x86/entry/entry_64.S +@@ -1064,7 +1064,7 @@ idtentry async_page_fault do_async_page_fault has_error_code=1 + #endif + + #ifdef CONFIG_X86_MCE +-idtentry machine_check has_error_code=0 paranoid=1 do_sym=*machine_check_vector(%rip) ++idtentry machine_check do_mce has_error_code=0 paranoid=1 + #endif + + /* +diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h +index 01fd0a7..688315b 100644 +--- a/arch/x86/include/asm/traps.h ++++ b/arch/x86/include/asm/traps.h +@@ -92,6 +92,7 @@ dotraplinkage void do_simd_coprocessor_error(struct pt_regs *, long); + #ifdef CONFIG_X86_32 + dotraplinkage void do_iret_error(struct pt_regs *, long); + #endif ++dotraplinkage void do_mce(struct pt_regs *, long); + + static inline int get_si_code(unsigned long condition) + { +diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c +index a7fdf45..0035aaa 100644 +--- a/arch/x86/kernel/cpu/mcheck/mce.c ++++ b/arch/x86/kernel/cpu/mcheck/mce.c +@@ -1765,6 +1765,11 @@ static void unexpected_machine_check(struct pt_regs *regs, long error_code) + void (*machine_check_vector)(struct pt_regs *, long error_code) = + unexpected_machine_check; + ++dotraplinkage void do_mce(struct pt_regs *regs, long error_code) ++{ ++ machine_check_vector(regs, error_code); ++} ++ + /* + * Called for each booted CPU to set up machine checks. + * Must be called with preempt off: +-- +2.7.4 + |