From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Thomas Lamprecht Date: Wed, 25 Sep 2019 10:48:48 +0200 Subject: [PATCH] [SIMD]: FPU register save/restore is also required on 5.0 kernels NOTE: the kernel needs to have the copy_kernel_to_xregs_err, copy_kernel_to_fxregs_err and copy_kernel_to_fregs_err functions backported for this to work. Signed-off-by: Thomas Lamprecht --- include/linux/simd_x86.h | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/include/linux/simd_x86.h b/include/linux/simd_x86.h index edd456098..98503a29e 100644 --- a/include/linux/simd_x86.h +++ b/include/linux/simd_x86.h @@ -181,7 +181,6 @@ kfpu_begin(void) preempt_disable(); local_irq_disable(); -#if defined(HAVE_KERNEL_TIF_NEED_FPU_LOAD) /* * The current FPU registers need to be preserved by kfpu_begin() * and restored by kfpu_end(). This is required because we can @@ -190,11 +189,11 @@ kfpu_begin(void) * context switch. */ copy_fpregs_to_fpstate(¤t->thread.fpu); -#elif defined(HAVE_KERNEL_FPU_INITIALIZED) + + +#if defined(HAVE_KERNEL_FPU_INITIALIZED) /* - * There is no need to preserve and restore the FPU registers. - * They will always be restored from the task's stored FPU state - * when switching contexts. + * Was removed with 5.2 as it was always set to 1 there */ WARN_ON_ONCE(current->thread.fpu.initialized == 0); #endif @@ -203,7 +202,6 @@ kfpu_begin(void) static inline void kfpu_end(void) { -#if defined(HAVE_KERNEL_TIF_NEED_FPU_LOAD) union fpregs_state *state = ¤t->thread.fpu.state; int error; @@ -215,7 +213,6 @@ kfpu_end(void) error = copy_kernel_to_fregs_err(&state->fsave); } WARN_ON_ONCE(error); -#endif local_irq_enable(); preempt_enable();