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Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Move-firmware_restrict_branch_specul.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Move-firmware_restrict_branch_specul.patch | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Move-firmware_restrict_branch_specul.patch b/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Move-firmware_restrict_branch_specul.patch new file mode 100644 index 00000000..29fb0352 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.9.21/0014-x86-speculation-Move-firmware_restrict_branch_specul.patch @@ -0,0 +1,76 @@ +From 9c1c34861d012ab32557236c23a303e70bef627e Mon Sep 17 00:00:00 2001 +From: Ingo Molnar <mingo@kernel.org> +Date: Wed, 21 Feb 2018 09:20:37 +0100 +Subject: [PATCH 14/14] x86/speculation: Move + firmware_restrict_branch_speculation_*() from C to CPP + +commit d72f4e29e6d84b7ec02ae93088aa459ac70e733b upstream. + +firmware_restrict_branch_speculation_*() recently started using +preempt_enable()/disable(), but those are relatively high level +primitives and cause build failures on some 32-bit builds. + +Since we want to keep <asm/nospec-branch.h> low level, convert +them to macros to avoid header hell... + +Cc: David Woodhouse <dwmw@amazon.co.uk> +Cc: Thomas Gleixner <tglx@linutronix.de> +Cc: Linus Torvalds <torvalds@linux-foundation.org> +Cc: Peter Zijlstra <peterz@infradead.org> +Cc: arjan.van.de.ven@intel.com +Cc: bp@alien8.de +Cc: dave.hansen@intel.com +Cc: jmattson@google.com +Cc: karahmed@amazon.de +Cc: kvm@vger.kernel.org +Cc: pbonzini@redhat.com +Cc: rkrcmar@redhat.com +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/include/asm/nospec-branch.h | 26 ++++++++++++++------------ + 1 file changed, 14 insertions(+), 12 deletions(-) + +diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h +index 29e8f30..d0dabea 100644 +--- a/arch/x86/include/asm/nospec-branch.h ++++ b/arch/x86/include/asm/nospec-branch.h +@@ -257,20 +257,22 @@ static inline void indirect_branch_prediction_barrier(void) + /* + * With retpoline, we must use IBRS to restrict branch prediction + * before calling into firmware. ++ * ++ * (Implemented as CPP macros due to header hell.) + */ +-static inline void firmware_restrict_branch_speculation_start(void) +-{ +- preempt_disable(); +- alternative_msr_write(MSR_IA32_SPEC_CTRL, SPEC_CTRL_IBRS, +- X86_FEATURE_USE_IBRS_FW); +-} ++#define firmware_restrict_branch_speculation_start() \ ++do { \ ++ preempt_disable(); \ ++ alternative_msr_write(MSR_IA32_SPEC_CTRL, SPEC_CTRL_IBRS, \ ++ X86_FEATURE_USE_IBRS_FW); \ ++} while (0) + +-static inline void firmware_restrict_branch_speculation_end(void) +-{ +- alternative_msr_write(MSR_IA32_SPEC_CTRL, 0, +- X86_FEATURE_USE_IBRS_FW); +- preempt_enable(); +-} ++#define firmware_restrict_branch_speculation_end() \ ++do { \ ++ alternative_msr_write(MSR_IA32_SPEC_CTRL, 0, \ ++ X86_FEATURE_USE_IBRS_FW); \ ++ preempt_enable(); \ ++} while (0) + + #endif /* __ASSEMBLY__ */ + +-- +2.7.4 + |