lkml.org 
[lkml]   [2021]   [Jun]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[patch V4 16/65] x86/fpu: Use copy_xstate_to_uabi_buf() in xfpregs_get()
    Use the new functionality of copy_xstate_to_uabi_buf() to retrieve the
    FX state when XSAVE* is in use. This avoids overwriting the FPU state
    buffer with fpstate_sanitize_xstate() which is error prone and duplicated
    code.

    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    Reviewed-by: Borislav Petkov <bp@suse.de>
    ---
    V3: Adopted to function rename
    V2: New patch
    ---
    arch/x86/kernel/fpu/regset.c | 11 ++++++++---
    1 file changed, 8 insertions(+), 3 deletions(-)

    --- a/arch/x86/kernel/fpu/regset.c
    +++ b/arch/x86/kernel/fpu/regset.c
    @@ -33,13 +33,18 @@ int xfpregs_get(struct task_struct *targ
    {
    struct fpu *fpu = &target->thread.fpu;

    - if (!boot_cpu_has(X86_FEATURE_FXSR))
    + if (!cpu_feature_enabled(X86_FEATURE_FXSR))
    return -ENODEV;

    fpu__prepare_read(fpu);
    - fpstate_sanitize_xstate(fpu);

    - return membuf_write(&to, &fpu->state.fxsave, sizeof(struct fxregs_state));
    + if (!use_xsave()) {
    + return membuf_write(&to, &fpu->state.fxsave,
    + sizeof(fpu->state.fxsave));
    + }
    +
    + copy_xstate_to_uabi_buf(to, &fpu->state.xsave, XSTATE_COPY_FX);
    + return 0;
    }

    int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
    \
     
     \ /
      Last update: 2021-06-23 14:24    [W:4.321 / U:0.148 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site