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author | Jens Axboe <axboe@kernel.dk> | 2018-02-05 12:55:38 -0700 |
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committer | Jens Axboe <axboe@kernel.dk> | 2018-02-05 12:55:38 -0700 |
commit | 9e05c864993c5442227f83ae1694a737d7a102ed (patch) | |
tree | e35b60bb3c0c179f147e9acaad5444f1e5d9117e /arch/x86/include/asm/barrier.h | |
parent | 3c15f3f545afa320c5e3822825a9a53c664776b6 (diff) | |
parent | 35277995e17919ab838beae765f440674e8576eb (diff) |
Merge branch 'master' into test
* master: (688 commits)
dt-bindings: mailbox: qcom: Document the APCS clock binding
mailbox: qcom: Create APCS child device for clock controller
mailbox: qcom: Convert APCS IPC driver to use regmap
KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRL
KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL
KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES
KVM/x86: Add IBPB support
KVM/x86: Update the reverse_cpuid list to include CPUID_7_EDX
pinctrl: remove include file from <linux/device.h>
firmware: dmi: handle missing DMI data gracefully
firmware: dmi_scan: Fix handling of empty DMI strings
firmware: dmi_scan: Drop dmi_initialized
firmware: dmi: Optimize dmi_matches
Revert "defer call to mem_cgroup_sk_alloc()"
soreuseport: fix mem leak in reuseport_add_sock()
net: qlge: use memmove instead of skb_copy_to_linear_data
net: qed: use correct strncpy() size
net: cxgb4: avoid memcpy beyond end of source buffer
cls_u32: add missing RCU annotation.
r8152: set rx mode early when linking on
...
Diffstat (limited to 'arch/x86/include/asm/barrier.h')
-rw-r--r-- | arch/x86/include/asm/barrier.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h index 7fb336210e1b..30d406146016 100644 --- a/arch/x86/include/asm/barrier.h +++ b/arch/x86/include/asm/barrier.h @@ -24,6 +24,34 @@ #define wmb() asm volatile("sfence" ::: "memory") #endif +/** + * array_index_mask_nospec() - generate a mask that is ~0UL when the + * bounds check succeeds and 0 otherwise + * @index: array element index + * @size: number of elements in array + * + * Returns: + * 0 - (index < size) + */ +static inline unsigned long array_index_mask_nospec(unsigned long index, + unsigned long size) +{ + unsigned long mask; + + asm ("cmp %1,%2; sbb %0,%0;" + :"=r" (mask) + :"r"(size),"r" (index) + :"cc"); + return mask; +} + +/* Override the default implementation from linux/nospec.h. */ +#define array_index_mask_nospec array_index_mask_nospec + +/* Prevent speculative execution past this barrier. */ +#define barrier_nospec() alternative_2("", "mfence", X86_FEATURE_MFENCE_RDTSC, \ + "lfence", X86_FEATURE_LFENCE_RDTSC) + #ifdef CONFIG_X86_PPRO_FENCE #define dma_rmb() rmb() #else |