From 4d981cf2d96f29cdfa7d4972c8b377fe7baa9c4c Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Sat, 23 Sep 2017 14:59:46 +0200 Subject: [PATCH] x86/fpu: Remove 'ubuf' parameter from the copy_xstate_to_kernel() APIs The 'ubuf' parameter is unused in the _kernel() side of the API, remove it. This simplifies the code and makes it easier to think about. Cc: Andrew Morton Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Eric Biggers Cc: Fenghua Yu Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Yu-cheng Yu Link: http://lkml.kernel.org/r/20170923130016.21448-4-mingo@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/include/asm/fpu/xstate.h | 2 +- arch/x86/kernel/fpu/regset.c | 2 +- arch/x86/kernel/fpu/xstate.c | 21 ++++++--------------- 3 files changed, 8 insertions(+), 17 deletions(-) diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index 92dc8ca..c762574 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -48,7 +48,7 @@ void fpu__xstate_clear_all_cpu_caps(void); void *get_xsave_addr(struct xregs_state *xsave, int xstate); const void *get_xsave_field_ptr(int xstate_field); int using_compacted_format(void); -int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf, struct xregs_state *xsave); +int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, struct xregs_state *xsave); int copy_xstate_to_user(unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf, struct xregs_state *xsave); int copy_user_to_xstate(const void *kbuf, const void __user *ubuf, struct xregs_state *xsave); diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index b6d12d6..34e74ad 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, if (using_compacted_format()) { if (kbuf) - ret = copy_xstate_to_kernel(pos, count, kbuf, ubuf, xsave); + ret = copy_xstate_to_kernel(pos, count, kbuf, xsave); else ret = copy_xstate_to_user(pos, count, kbuf, ubuf, xsave); } else { diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 3856153..71d3bda 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -926,7 +926,7 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, */ static inline int __copy_xstate_to_kernel(unsigned int pos, unsigned int count, - void *kbuf, void __user *ubuf, + void *kbuf, const void *data, const int start_pos, const int end_pos) { @@ -936,12 +936,7 @@ __copy_xstate_to_kernel(unsigned int pos, unsigned int count, if (end_pos < 0 || pos < end_pos) { unsigned int copy = (end_pos < 0 ? count : min(count, end_pos - pos)); - if (kbuf) { - memcpy(kbuf + pos, data, copy); - } else { - if (__copy_to_user(ubuf + pos, data, copy)) - return -EFAULT; - } + memcpy(kbuf + pos, data, copy); } return 0; } @@ -953,8 +948,7 @@ __copy_xstate_to_kernel(unsigned int pos, unsigned int count, * It supports partial copy but pos always starts from zero. This is called * from xstateregs_get() and there we check the CPU has XSAVES. */ -int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, - void __user *ubuf, struct xregs_state *xsave) +int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, struct xregs_state *xsave) { unsigned int offset, size; int ret, i; @@ -979,8 +973,7 @@ int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, offset = offsetof(struct xregs_state, header); size = sizeof(header); - ret = __copy_xstate_to_kernel(offset, size, kbuf, ubuf, &header, 0, count); - + ret = __copy_xstate_to_kernel(offset, size, kbuf, &header, 0, count); if (ret) return ret; @@ -994,8 +987,7 @@ int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, offset = xstate_offsets[i]; size = xstate_sizes[i]; - ret = __copy_xstate_to_kernel(offset, size, kbuf, ubuf, src, 0, count); - + ret = __copy_xstate_to_kernel(offset, size, kbuf, src, 0, count); if (ret) return ret; @@ -1011,8 +1003,7 @@ int copy_xstate_to_kernel(unsigned int pos, unsigned int count, void *kbuf, offset = offsetof(struct fxregs_state, sw_reserved); size = sizeof(xstate_fx_sw_bytes); - ret = __copy_xstate_to_kernel(offset, size, kbuf, ubuf, xstate_fx_sw_bytes, 0, count); - + ret = __copy_xstate_to_kernel(offset, size, kbuf, xstate_fx_sw_bytes, 0, count); if (ret) return ret; -- 2.7.4