x86, ptrace: regset extensions to support xstate

Add the xstate regset support which helps extend the kernel ptrace and the
core-dump interfaces to support AVX state etc.

This regset interface is designed to support all the future state that gets
supported using xsave/xrstor infrastructure.

Looking at the memory layout saved by "xsave", one can't say which state
is represented in the memory layout. This is because if a particular state is
in init state, in the xsave hdr it can be represented by bit '0'. And hence
we can't really say by the xsave header wether a state is in init state or
the state is not saved in the memory layout.

And hence the xsave memory layout available through this regset
interface uses SW usable bytes [464..511] to convey what state is represented
in the memory layout.

First 8 bytes of the sw_usable_bytes[464..467] will be set to OS enabled xstate
mask(which is same as the 64bit mask returned by the xgetbv's xCR0).

The note NT_X86_XSTATE represents the extended state information in the
core file, using the above mentioned memory layout.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100211195614.802495327@sbs-t61.sc.intel.com>
Signed-off-by: Hongjiu Lu <hjl.tools@gmail.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Suresh Siddha
2010-02-11 11:50:59 -08:00
committed by H. Peter Anvin
parent 676ad58553
commit 5b3efd5008
7 changed files with 187 additions and 4 deletions

View File

@@ -48,6 +48,7 @@ enum x86_regset {
REGSET_FP,
REGSET_XFP,
REGSET_IOPERM64 = REGSET_XFP,
REGSET_XSTATE,
REGSET_TLS,
REGSET_IOPERM32,
};
@@ -1584,7 +1585,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
#ifdef CONFIG_X86_64
static const struct user_regset x86_64_regsets[] = {
static struct user_regset x86_64_regsets[] __read_mostly = {
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = sizeof(struct user_regs_struct) / sizeof(long),
@@ -1597,6 +1598,12 @@ static const struct user_regset x86_64_regsets[] = {
.size = sizeof(long), .align = sizeof(long),
.active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
},
[REGSET_XSTATE] = {
.core_note_type = NT_X86_XSTATE,
.size = sizeof(u64), .align = sizeof(u64),
.active = xstateregs_active, .get = xstateregs_get,
.set = xstateregs_set
},
[REGSET_IOPERM64] = {
.core_note_type = NT_386_IOPERM,
.n = IO_BITMAP_LONGS,
@@ -1622,7 +1629,7 @@ static const struct user_regset_view user_x86_64_view = {
#endif /* CONFIG_X86_64 */
#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
static const struct user_regset x86_32_regsets[] = {
static struct user_regset x86_32_regsets[] __read_mostly = {
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = sizeof(struct user_regs_struct32) / sizeof(u32),
@@ -1641,6 +1648,12 @@ static const struct user_regset x86_32_regsets[] = {
.size = sizeof(u32), .align = sizeof(u32),
.active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
},
[REGSET_XSTATE] = {
.core_note_type = NT_X86_XSTATE,
.size = sizeof(u64), .align = sizeof(u64),
.active = xstateregs_active, .get = xstateregs_get,
.set = xstateregs_set
},
[REGSET_TLS] = {
.core_note_type = NT_386_TLS,
.n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
@@ -1663,6 +1676,23 @@ static const struct user_regset_view user_x86_32_view = {
};
#endif
/*
* This represents bytes 464..511 in the memory layout exported through
* the REGSET_XSTATE interface.
*/
u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
void update_regset_xstate_info(unsigned int size, u64 xstate_mask)
{
#ifdef CONFIG_X86_64
x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
#endif
#if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
#endif
xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
}
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#ifdef CONFIG_IA32_EMULATION