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authorLinus Torvalds <torvalds@linux-foundation.org>2010-10-21 13:34:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-10-21 13:34:32 -0700
commitb6f7e38dbb310557fe890b04b1a376c93f638c3b (patch)
tree244aa0cac6ceedfd208438f9c741211842c1aa3b /arch/x86/kernel/i387.c
parent214515b5787a1035b2c8807abe8be569de63b2f6 (diff)
parentb2b57fe053c9cf8b8af5a0e826a465996afed0ff (diff)
Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, fpu: Merge fpu_save_init() x86-32, fpu: Rewrite fpu_save_init() x86, fpu: Remove PSHUFB_XMM5_* macros x86, fpu: Remove unnecessary ifdefs from i387 code. x86-32, fpu: Remove math_emulate stub x86-64, fpu: Simplify constraints for fxsave/fxtstor x86-64, fpu: Fix %cs value in convert_from_fxsr() x86-64, fpu: Disable preemption when using TS_USEDFPU x86, fpu: Merge __save_init_fpu() x86, fpu: Merge tolerant_fwait() x86, fpu: Merge fpu_init() x86: Use correct type for %cr4 x86, xsave: Disable xsave in i387 emulation mode Fixed up fxsaveq-induced conflict in arch/x86/include/asm/i387.h
Diffstat (limited to 'arch/x86/kernel/i387.c')
-rw-r--r--arch/x86/kernel/i387.c58
1 files changed, 28 insertions, 30 deletions
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index a46cb3522c0..58bb239a2fd 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -68,19 +68,22 @@ static void __cpuinit init_thread_xstate(void)
*/
if (!HAVE_HWFP) {
+ /*
+ * Disable xsave as we do not support it if i387
+ * emulation is enabled.
+ */
+ setup_clear_cpu_cap(X86_FEATURE_XSAVE);
+ setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
xstate_size = sizeof(struct i387_soft_struct);
return;
}
if (cpu_has_fxsr)
xstate_size = sizeof(struct i387_fxsave_struct);
-#ifdef CONFIG_X86_32
else
xstate_size = sizeof(struct i387_fsave_struct);
-#endif
}
-#ifdef CONFIG_X86_64
/*
* Called at bootup to set up the initial FPU state that is later cloned
* into all processes.
@@ -88,12 +91,21 @@ static void __cpuinit init_thread_xstate(void)
void __cpuinit fpu_init(void)
{
- unsigned long oldcr0 = read_cr0();
-
- set_in_cr4(X86_CR4_OSFXSR);
- set_in_cr4(X86_CR4_OSXMMEXCPT);
+ unsigned long cr0;
+ unsigned long cr4_mask = 0;
- write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */
+ if (cpu_has_fxsr)
+ cr4_mask |= X86_CR4_OSFXSR;
+ if (cpu_has_xmm)
+ cr4_mask |= X86_CR4_OSXMMEXCPT;
+ if (cr4_mask)
+ set_in_cr4(cr4_mask);
+
+ cr0 = read_cr0();
+ cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */
+ if (!HAVE_HWFP)
+ cr0 |= X86_CR0_EM;
+ write_cr0(cr0);
if (!smp_processor_id())
init_thread_xstate();
@@ -104,24 +116,12 @@ void __cpuinit fpu_init(void)
clear_used_math();
}
-#else /* CONFIG_X86_64 */
-
-void __cpuinit fpu_init(void)
-{
- if (!smp_processor_id())
- init_thread_xstate();
-}
-
-#endif /* CONFIG_X86_32 */
-
void fpu_finit(struct fpu *fpu)
{
-#ifdef CONFIG_X86_32
if (!HAVE_HWFP) {
finit_soft_fpu(&fpu->state->soft);
return;
}
-#endif
if (cpu_has_fxsr) {
struct i387_fxsave_struct *fx = &fpu->state->fxsave;
@@ -386,19 +386,17 @@ convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk)
#ifdef CONFIG_X86_64
env->fip = fxsave->rip;
env->foo = fxsave->rdp;
+ /*
+ * should be actually ds/cs at fpu exception time, but
+ * that information is not available in 64bit mode.
+ */
+ env->fcs = task_pt_regs(tsk)->cs;
if (tsk == current) {
- /*
- * should be actually ds/cs at fpu exception time, but
- * that information is not available in 64bit mode.
- */
- asm("mov %%ds, %[fos]" : [fos] "=r" (env->fos));
- asm("mov %%cs, %[fcs]" : [fcs] "=r" (env->fcs));
+ savesegment(ds, env->fos);
} else {
- struct pt_regs *regs = task_pt_regs(tsk);
-
- env->fos = 0xffff0000 | tsk->thread.ds;
- env->fcs = regs->cs;
+ env->fos = tsk->thread.ds;
}
+ env->fos |= 0xffff0000;
#else
env->fip = fxsave->fip;
env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16);