diff options
| -rw-r--r-- | arch/x86/include/asm/fpu/xstate.h | 12 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/regset.c | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 42 |
3 files changed, 42 insertions, 14 deletions
diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index 1bb2d16f485b2..732ae793c2ab3 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -103,12 +103,20 @@ extern void __init update_regset_xstate_info(unsigned int size, void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr); int using_compacted_format(void); int xfeature_size(int xfeature_nr); -struct membuf; -void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave); int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf); int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf); void copy_supervisor_to_kernel(struct xregs_state *xsave); void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask); void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask); +enum xstate_copy_mode { + XSTATE_COPY_FP, + XSTATE_COPY_FX, + XSTATE_COPY_XSAVE, +}; + +struct membuf; +void copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, + enum xstate_copy_mode mode); + #endif diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index 7041b140de604..783f84dfcd466 100644 --- a/arch/x86/kernel/fpu/regset.c +++ b/arch/x86/kernel/fpu/regset.c @@ -93,7 +93,7 @@ int xstateregs_get(struct task_struct *target, const struct user_regset *regset, fpu__prepare_read(fpu); - copy_xstate_to_kernel(to, &fpu->state.xsave); + copy_xstate_to_uabi_buf(to, &fpu->state.xsave, XSTATE_COPY_XSAVE); return 0; } diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 42032471c9573..8d023a26ae222 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1068,14 +1068,20 @@ static void copy_feature(bool from_xstate, struct membuf *to, void *xstate, membuf_write(to, from_xstate ? xstate : init_xstate, size); } -/* - * Convert from kernel XSAVE or XSAVES compacted format to UABI - * non-compacted format and copy to a kernel-space ptrace buffer. +/** + * copy_xstate_to_uabi_buf - Copy kernel saved xstate to a UABI buffer + * @to: membuf descriptor + * @xsave: The kernel xstate buffer to copy from + * @copy_mode: The requested copy mode + * + * Converts from kernel XSAVE or XSAVES compacted format to UABI conforming + * format, i.e. from the kernel internal hardware dependent storage format + * to the requested @mode. UABI XSTATE is always uncompacted! * - * It supports partial copy but pos always starts from zero. This is called - * from xstateregs_get() and there we check the CPU has XSAVE. + * It supports partial copy but @to.pos always starts from zero. */ -void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave) +void copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, + enum xstate_copy_mode copy_mode) { const unsigned int off_mxcsr = offsetof(struct fxregs_state, mxcsr); struct xregs_state *xinit = &init_fpstate.xsave; @@ -1083,12 +1089,22 @@ void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave) unsigned int zerofrom; int i; - /* - * The destination is a ptrace buffer; we put in only user xstates: - */ - memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; - header.xfeatures &= xfeatures_mask_user(); + + /* Mask out the feature bits depending on copy mode */ + switch (copy_mode) { + case XSTATE_COPY_FP: + header.xfeatures &= XFEATURE_MASK_FP; + break; + + case XSTATE_COPY_FX: + header.xfeatures &= XFEATURE_MASK_FP | XFEATURE_MASK_SSE; + break; + + case XSTATE_COPY_XSAVE: + header.xfeatures &= xfeatures_mask_user(); + break; + } /* Copy FP state up to MXCSR */ copy_feature(header.xfeatures & XFEATURE_MASK_FP, &to, &xsave->i387, @@ -1109,6 +1125,9 @@ void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave) &to, &xsave->i387.xmm_space, &xinit->i387.xmm_space, sizeof(xsave->i387.xmm_space)); + if (copy_mode != XSTATE_COPY_XSAVE) + goto out; + /* Zero the padding area */ membuf_zero(&to, sizeof(xsave->i387.padding)); @@ -1150,6 +1169,7 @@ void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave) zerofrom = xstate_offsets[i] + xstate_sizes[i]; } +out: if (to.left) membuf_zero(&to, to.left); } |