diff options
| -rw-r--r-- | arch/x86/kernel/xsave.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index 980149867a1..4993caa4181 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -21,6 +21,8 @@ struct _fpx_sw_bytes fx_sw_reserved; struct _fpx_sw_bytes fx_sw_reserved_ia32; #endif +static unsigned int *xstate_offsets, *xstate_sizes, xstate_features; + /* * Check for the presence of extended state information in the * user fpstate pointer in the sigcontext. @@ -302,12 +304,39 @@ void __cpuinit xsave_init(void) } /* + * Record the offsets and sizes of different state managed by the xsave + * memory layout. + */ +static void setup_xstate_features(void) +{ + int eax, ebx, ecx, edx, leaf = 0x2; + + xstate_features = fls64(pcntxt_mask); + xstate_offsets = alloc_bootmem(xstate_features * sizeof(int)); + xstate_sizes = alloc_bootmem(xstate_features * sizeof(int)); + + do { + cpuid_count(0xd, leaf, &eax, &ebx, &ecx, &edx); + + if (eax == 0) + break; + + xstate_offsets[leaf] = ebx; + xstate_sizes[leaf] = eax; + + leaf++; + } while (1); +} + +/* * setup the xstate image representing the init state */ static void __init setup_xstate_init(void) { init_xstate_buf = alloc_bootmem(xstate_size); init_xstate_buf->i387.mxcsr = MXCSR_DEFAULT; + + setup_xstate_features(); } /* |