From 6aa6dbfced51dec6cde159c6167ad3dad6add823 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Tue, 5 Apr 2016 08:29:55 +0200 Subject: [PATCH] x86/fpu: Get rid of x87 math exception helpers ... and integrate their functionality into their single user fpu__exception_code(). No functionality change. Signed-off-by: Borislav Petkov Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1459837795-2588-7-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/fpu/core.c | 44 +++++++++++--------------------------- 1 file changed, 13 insertions(+), 31 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 1551b28398a4..97027545a72d 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -506,33 +506,6 @@ void fpu__clear(struct fpu *fpu) * x87 math exception handling: */ -static inline unsigned short get_fpu_cwd(struct fpu *fpu) -{ - if (boot_cpu_has(X86_FEATURE_FXSR)) { - return fpu->state.fxsave.cwd; - } else { - return (unsigned short)fpu->state.fsave.cwd; - } -} - -static inline unsigned short get_fpu_swd(struct fpu *fpu) -{ - if (boot_cpu_has(X86_FEATURE_FXSR)) { - return fpu->state.fxsave.swd; - } else { - return (unsigned short)fpu->state.fsave.swd; - } -} - -static inline unsigned short get_fpu_mxcsr(struct fpu *fpu) -{ - if (boot_cpu_has(X86_FEATURE_XMM)) { - return fpu->state.fxsave.mxcsr; - } else { - return MXCSR_DEFAULT; - } -} - int fpu__exception_code(struct fpu *fpu, int trap_nr) { int err; @@ -547,10 +520,15 @@ int fpu__exception_code(struct fpu *fpu, int trap_nr) * so if this combination doesn't produce any single exception, * then we have a bad program that isn't synchronizing its FPU usage * and it will suffer the consequences since we won't be able to - * fully reproduce the context of the exception + * fully reproduce the context of the exception. */ - cwd = get_fpu_cwd(fpu); - swd = get_fpu_swd(fpu); + if (boot_cpu_has(X86_FEATURE_FXSR)) { + cwd = fpu->state.fxsave.cwd; + swd = fpu->state.fxsave.swd; + } else { + cwd = (unsigned short)fpu->state.fsave.cwd; + swd = (unsigned short)fpu->state.fsave.swd; + } err = swd & ~cwd; } else { @@ -560,7 +538,11 @@ int fpu__exception_code(struct fpu *fpu, int trap_nr) * unmasked exception was caught we must mask the exception mask bits * at 0x1f80, and then use these to mask the exception bits at 0x3f. */ - unsigned short mxcsr = get_fpu_mxcsr(fpu); + unsigned short mxcsr = MXCSR_DEFAULT; + + if (boot_cpu_has(X86_FEATURE_XMM)) + mxcsr = fpu->state.fxsave.mxcsr; + err = ~(mxcsr >> 7) & mxcsr; } -- 2.20.1