diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index 43ae89d4bcd237e7c2b1f7cbaf11bb486b0c5df8..cf285464eabee6a004ba560974f2c95f20b8130b 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -43,6 +43,9 @@ #define XFEATURE_MASK_USER_RESTORE \ (XFEATURE_MASK_USER_SUPPORTED & ~XFEATURE_MASK_PKRU) +/* Features which are dynamically enabled for a process on request */ +#define XFEATURE_MASK_USER_DYNAMIC 0ULL + /* All currently supported supervisor features */ #define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID) @@ -96,4 +99,22 @@ int xfeature_size(int xfeature_nr); void xsaves(struct xregs_state *xsave, u64 mask); void xrstors(struct xregs_state *xsave, u64 mask); +#ifdef CONFIG_X86_64 +DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); +#endif + +#ifdef CONFIG_X86_64 +DECLARE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); + +static __always_inline __pure bool fpu_state_size_dynamic(void) +{ + return static_branch_unlikely(&__fpu_state_size_dynamic); +} +#else +static __always_inline __pure bool fpu_state_size_dynamic(void) +{ + return false; +} +#endif + #endif diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index b05f6a3b205782e75a4ad6ff9320bcde66d77f24..4018083c5b3627f27a37c7cdbb78c078a4a10867 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -25,6 +25,10 @@ #define CREATE_TRACE_POINTS #include +#ifdef CONFIG_X86_64 +DEFINE_STATIC_KEY_FALSE(__fpu_state_size_dynamic); +#endif + /* The FPU state configuration data for kernel and user space */ struct fpu_state_config fpu_kernel_cfg __ro_after_init; struct fpu_state_config fpu_user_cfg __ro_after_init;