diff options
Diffstat (limited to 'arch/x86/kernel/fpu/xstate.c')
-rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 63 |
1 files changed, 62 insertions, 1 deletions
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 038e19c0019e..5d8047441a0a 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -37,6 +37,7 @@ static const char *xfeature_names[] = "AVX-512 ZMM_Hi256" , "Processor Trace (unused)" , "Protection Keys User registers", + "PASID state", "unknown xstate feature" , }; @@ -51,6 +52,7 @@ static short xsave_cpuid_features[] __initdata = { X86_FEATURE_AVX512F, X86_FEATURE_INTEL_PT, X86_FEATURE_PKU, + X86_FEATURE_ENQCMD, }; /* @@ -318,6 +320,7 @@ static void __init print_xstate_features(void) print_xstate_feature(XFEATURE_MASK_ZMM_Hi256); print_xstate_feature(XFEATURE_MASK_Hi16_ZMM); print_xstate_feature(XFEATURE_MASK_PKRU); + print_xstate_feature(XFEATURE_MASK_PASID); } /* @@ -592,6 +595,7 @@ static void check_xstate_against_struct(int nr) XCHECK_SZ(sz, nr, XFEATURE_ZMM_Hi256, struct avx_512_zmm_uppers_state); XCHECK_SZ(sz, nr, XFEATURE_Hi16_ZMM, struct avx_512_hi16_state); XCHECK_SZ(sz, nr, XFEATURE_PKRU, struct pkru_state); + XCHECK_SZ(sz, nr, XFEATURE_PASID, struct ia32_pasid_state); /* * Make *SURE* to add any feature numbers in below if @@ -601,7 +605,7 @@ static void check_xstate_against_struct(int nr) if ((nr < XFEATURE_YMM) || (nr >= XFEATURE_MAX) || (nr == XFEATURE_PT_UNIMPLEMENTED_SO_FAR) || - ((nr >= XFEATURE_RSRVD_COMP_10) && (nr <= XFEATURE_LBR))) { + ((nr >= XFEATURE_RSRVD_COMP_11) && (nr <= XFEATURE_LBR))) { WARN_ONCE(1, "no structure for xstate: %d\n", nr); XSTATE_WARN_ON(1); } @@ -1398,3 +1402,60 @@ int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns, return 0; } #endif /* CONFIG_PROC_PID_ARCH_STATUS */ + +#ifdef CONFIG_IOMMU_SUPPORT +void update_pasid(void) +{ + u64 pasid_state; + u32 pasid; + + if (!cpu_feature_enabled(X86_FEATURE_ENQCMD)) + return; + + if (!current->mm) + return; + + pasid = READ_ONCE(current->mm->pasid); + /* Set the valid bit in the PASID MSR/state only for valid pasid. */ + pasid_state = pasid == PASID_DISABLED ? + pasid : pasid | MSR_IA32_PASID_VALID; + + /* + * No need to hold fregs_lock() since the task's fpstate won't + * be changed by others (e.g. ptrace) while the task is being + * switched to or is in IPI. + */ + if (!test_thread_flag(TIF_NEED_FPU_LOAD)) { + /* The MSR is active and can be directly updated. */ + wrmsrl(MSR_IA32_PASID, pasid_state); + } else { + struct fpu *fpu = ¤t->thread.fpu; + struct ia32_pasid_state *ppasid_state; + struct xregs_state *xsave; + + /* + * The CPU's xstate registers are not currently active. Just + * update the PASID state in the memory buffer here. The + * PASID MSR will be loaded when returning to user mode. + */ + xsave = &fpu->state.xsave; + xsave->header.xfeatures |= XFEATURE_MASK_PASID; + ppasid_state = get_xsave_addr(xsave, XFEATURE_PASID); + /* + * Since XFEATURE_MASK_PASID is set in xfeatures, ppasid_state + * won't be NULL and no need to check its value. + * + * Only update the task's PASID state when it's different + * from the mm's pasid. + */ + if (ppasid_state->pasid != pasid_state) { + /* + * Invalid fpregs so that state restoring will pick up + * the PASID state. + */ + __fpu_invalidate_fpregs_state(fpu); + ppasid_state->pasid = pasid_state; + } + } +} +#endif /* CONFIG_IOMMU_SUPPORT */ |