The following commit has been merged into the x86/fpu branch of tip: Commit-ID: 3ac8d75778fc8c1c22daad9bc674166b862f6f6e Gitweb: https://git.kernel.org/tip/3ac8d75778fc8c1c22daad9bc674166b862f6f6e Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Wed, 13 Oct 2021 16:55:54 +02:00 Committer: Borislav Petkov <bp@xxxxxxx> CommitterDate: Thu, 21 Oct 2021 14:18:23 +02:00 x86/fpu: Use fpstate in __copy_xstate_to_uabi_buf() With dynamically enabled features the copy function must know the features and the size which is valid for the task. Retrieve them from fpstate. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Link: https://lkml.kernel.org/r/20211013145323.181495492@xxxxxxxxxxxxx --- arch/x86/kernel/fpu/core.c | 8 ++++---- arch/x86/kernel/fpu/xstate.c | 11 ++++++----- arch/x86/kernel/fpu/xstate.h | 2 +- 3 files changed, 11 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 052e5ef..04fef47 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -187,15 +187,15 @@ EXPORT_SYMBOL_GPL(fpu_swap_kvm_fpu); void fpu_copy_fpstate_to_kvm_uabi(struct fpu *fpu, void *buf, unsigned int size, u32 pkru) { - union fpregs_state *kstate = &fpu->fpstate->regs; + struct fpstate *kstate = fpu->fpstate; union fpregs_state *ustate = buf; struct membuf mb = { .p = buf, .left = size }; if (cpu_feature_enabled(X86_FEATURE_XSAVE)) { - __copy_xstate_to_uabi_buf(mb, &kstate->xsave, pkru, - XSTATE_COPY_XSAVE); + __copy_xstate_to_uabi_buf(mb, kstate, pkru, XSTATE_COPY_XSAVE); } else { - memcpy(&ustate->fxsave, &kstate->fxsave, sizeof(ustate->fxsave)); + memcpy(&ustate->fxsave, &kstate->regs.fxsave, + sizeof(ustate->fxsave)); /* Make it restorable on a XSAVE enabled host */ ustate->xsave.header.xfeatures = XFEATURE_MASK_FPSSE; } diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 4beb010..54cc0a4 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -969,7 +969,7 @@ static void copy_feature(bool from_xstate, struct membuf *to, void *xstate, /** * __copy_xstate_to_uabi_buf - Copy kernel saved xstate to a UABI buffer * @to: membuf descriptor - * @xsave: The xsave from which to copy + * @fpstate: The fpstate buffer from which to copy * @pkru_val: The PKRU value to store in the PKRU component * @copy_mode: The requested copy mode * @@ -979,11 +979,12 @@ static void copy_feature(bool from_xstate, struct membuf *to, void *xstate, * * It supports partial copy but @to.pos always starts from zero. */ -void __copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, +void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate, u32 pkru_val, enum xstate_copy_mode copy_mode) { const unsigned int off_mxcsr = offsetof(struct fxregs_state, mxcsr); struct xregs_state *xinit = &init_fpstate.regs.xsave; + struct xregs_state *xsave = &fpstate->regs.xsave; struct xstate_header header; unsigned int zerofrom; u64 mask; @@ -1003,7 +1004,7 @@ void __copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, break; case XSTATE_COPY_XSAVE: - header.xfeatures &= xfeatures_mask_uabi(); + header.xfeatures &= fpstate->user_xfeatures; break; } @@ -1046,7 +1047,7 @@ void __copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, * but there is no state to copy from in the compacted * init_fpstate. The gap tracking will zero these states. */ - mask = xfeatures_mask_uabi(); + mask = fpstate->user_xfeatures; for_each_extended_xfeature(i, mask) { /* @@ -1097,7 +1098,7 @@ out: void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk, enum xstate_copy_mode copy_mode) { - __copy_xstate_to_uabi_buf(to, &tsk->thread.fpu.fpstate->regs.xsave, + __copy_xstate_to_uabi_buf(to, tsk->thread.fpu.fpstate, tsk->thread.pkru, copy_mode); } diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h index 3e9eaf9..b74c595 100644 --- a/arch/x86/kernel/fpu/xstate.h +++ b/arch/x86/kernel/fpu/xstate.h @@ -15,7 +15,7 @@ static inline void xstate_init_xcomp_bv(struct xregs_state *xsave, u64 mask) xsave->header.xcomp_bv = mask | XCOMP_BV_COMPACTED_FORMAT; } -extern void __copy_xstate_to_uabi_buf(struct membuf to, struct xregs_state *xsave, +extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate, u32 pkru_val, enum xstate_copy_mode copy_mode); extern void fpu__init_cpu_xstate(void);
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