x86/fpu: Prepare copy_fpstate_to_sigframe() for TIF_NEED_FPU_LOAD
The FPU registers need only to be saved if TIF_NEED_FPU_LOAD is not set. Otherwise this has been already done and can be skipped. [ bp: Massage a bit. ] Signed-off-by: Rik van Riel <riel@surriel.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@surriel.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20190403164156.19645-19-bigeasy@linutronix.de
This commit is contained in:
Родитель
69277c98f5
Коммит
a352a3b7b7
|
@ -171,7 +171,17 @@ int copy_fpstate_to_sigframe(void __user *buf, void __user *buf_fx, int size)
|
||||||
sizeof(struct user_i387_ia32_struct), NULL,
|
sizeof(struct user_i387_ia32_struct), NULL,
|
||||||
(struct _fpstate_32 __user *) buf) ? -1 : 1;
|
(struct _fpstate_32 __user *) buf) ? -1 : 1;
|
||||||
|
|
||||||
copy_fpregs_to_fpstate(fpu);
|
/*
|
||||||
|
* If we do not need to load the FPU registers at return to userspace
|
||||||
|
* then the CPU has the current state and we need to save it. Otherwise,
|
||||||
|
* it has already been done and we can skip it.
|
||||||
|
*/
|
||||||
|
fpregs_lock();
|
||||||
|
if (!test_thread_flag(TIF_NEED_FPU_LOAD)) {
|
||||||
|
copy_fpregs_to_fpstate(fpu);
|
||||||
|
set_thread_flag(TIF_NEED_FPU_LOAD);
|
||||||
|
}
|
||||||
|
fpregs_unlock();
|
||||||
|
|
||||||
if (using_compacted_format()) {
|
if (using_compacted_format()) {
|
||||||
if (copy_xstate_to_user(buf_fx, xsave, 0, size))
|
if (copy_xstate_to_user(buf_fx, xsave, 0, size))
|
||||||
|
|
Загрузка…
Ссылка в новой задаче