XSAVES is a kernel-mode instruction. It offers a compacted format and
memory-write optimization. These patches fix issues in the first
implementation. They are intended for discussion and getting feedback
before actually getting applied.
Changes since Version 4:
Patch 4 - Introduce a new check to copy registers directly to signal
frame: Simplify the check for compacted format.
Patch 7 - Fix PTRACE frames for XSAVES: If PTRACE attempts to set
any disabled xstate, return failure; using_compacted_format()
is used when appropriate.
New additions:
Patch 10 - Fix __fp_restore_sig() for xsaves: it was doing direct
copying from user mode standard format to kernel mode,
which could be in compacted format. Fix it by restoring
directly to registers.
Patch 11 - Add WARN_ON_FPU() when a disabled xstate component is
requested for a compacted format.
Patch 12 - Fix fpstate_init() for XSAVES: xcomp_bv[63] must be set
for XSAVES.
Yu-cheng Yu (13):
x86/xsaves: Define and use user_xstate_size for xstate size in signal
context
x86/xsaves: Rename xstate_size to kernel_xstate_size to explicitly
distinguish xstate size in kernel from user space
x86/xsaves: Keep init_fpstate.xsave.header.xfeatures as zero for init
optimization
x86/xsaves: Introduce a new check that allows correct xstates copy
from kernel to user directly
x86/xsaves: Align xstate components according to CPUID
x86/xsaves: Supervisor state component offset
x86/xsaves: Fix PTRACE frames for XSAVES
x86/xsaves: Fix XSTATE component offset print out
x86/xsaves: Fix xstate_offsets, xstate_sizes for non-extended states
x86/xsaves: Fix __fpu_restore_sig() for XSAVES
x86/xsaves: Add WARN_ON_FPU() when a disabled xstate component offset
is requested for a compacted format
x86/xsaves: Fix fpstate_init() for XSAVES
x86/xsaves: Re-enable XSAVES
arch/x86/include/asm/fpu/types.h | 1 +
arch/x86/include/asm/fpu/xstate.h | 10 +-
arch/x86/include/asm/processor.h | 3 +-
arch/x86/kernel/fpu/core.c | 9 +-
arch/x86/kernel/fpu/init.c | 32 +--
arch/x86/kernel/fpu/regset.c | 56 ++++--
arch/x86/kernel/fpu/signal.c | 42 +++-
arch/x86/kernel/fpu/xstate.c | 408 ++++++++++++++++++++++++++++++--------
8 files changed, 420 insertions(+), 141 deletions(-)
--
1.9.1
