Message ID | CAMe9rOqXc3C_-b9s+TUPA5-VN1UzDSoXEU8L=KM1M-tK_WCzhQ@mail.gmail.com |
---|---|
State | New |
Headers | show |
Series | V3: [PATCH 01/24] x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t [BZ #22563] | expand |
On 07/13/2018 04:49 PM, H.J. Lu wrote: > On Fri, Jul 13, 2018 at 11:51 AM, Carlos O'Donell <carlos@redhat.com> wrote: >> On 07/13/2018 09:19 AM, H.J. Lu wrote: >>> On Wed, Jun 13, 2018 at 08:31:44AM -0700, H.J. Lu wrote: >>>> This will be used by CET run-time control. >>>> >>>> [BZ #22563] >>>> * nptl/pthread_create.c (__pthread_create_2_1): Use >>>> THREAD_COPY_ADDITONAL_INFO to copy additonal info if defined. >>>> * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. >>>> * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): >>>> Likewise. >>>> * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 >>>> to feature_1. >>>> * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. >>>> * sysdeps/unix/sysv/linux/x86/pthreaddef.h: New file. >>> Here is the updated patch to add feature_1 to tcbhead_t and >>> introduce macros for CET enabling. OK for master? >> Fix the typo-prone macro API and post a v3 please. >> >> Thank you. >> >>> H.J. >>> ---- >>> feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET >>> run-time control. >>> >>> CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to >>> indicate that if CET, IBT and SHSTK are enabled. >> OK. >> >>> [BZ #22563] >>> * nptl/pthread_create.c (__pthread_create_2_1): Use >>> THREAD_COPY_ADDITONAL_INFO to copy additonal info if defined. >>> * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. >>> * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): >>> Likewise. >>> * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 >>> to feature_1. >>> * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. >>> * sysdeps/unix/sysv/linux/x86/pthreaddef.h: New file. >>> * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. >>> (X86_FEATURE_1_SHSTK): Likewise. >>> (CET_ENABLED): Likewise. >>> (IBT_ENABLED): Likewise. >>> (SHSTK_ENABLED): Likewise. >>> --- >>> nptl/pthread_create.c | 5 +++++ >>> sysdeps/i386/nptl/tcb-offsets.sym | 1 + >>> sysdeps/i386/nptl/tls.h | 5 ++++- >>> sysdeps/unix/sysv/linux/x86/pthreaddef.h | 24 +++++++++++++++++++++ >>> sysdeps/x86/sysdep.h | 27 ++++++++++++++++++++++++ >>> sysdeps/x86_64/nptl/tcb-offsets.sym | 1 + >>> sysdeps/x86_64/nptl/tls.h | 5 ++++- >>> 7 files changed, 66 insertions(+), 2 deletions(-) >>> create mode 100644 sysdeps/unix/sysv/linux/x86/pthreaddef.h >>> >>> diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c >>> index 92c945b12b..16998f4bbd 100644 >>> --- a/nptl/pthread_create.c >>> +++ b/nptl/pthread_create.c >>> @@ -712,6 +712,11 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, >>> THREAD_COPY_POINTER_GUARD (pd); >>> #endif >>> >>> + /* Copy additonal info. */ >>> +#ifdef THREAD_COPY_ADDITONAL_INFO >>> + THREAD_COPY_ADDITONAL_INFO (pd); >>> +#endif >> This is a typo-prone macro API. >> >> Please find a way to define this unconditionally. >> > Here is the V3 patch. I added <tls-setup.h> to set up thread-local data. > OK for master? This version looks good. I have to go over your other patches and continue reviewing. Thanks for the new versions. Please commit. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > Thanks. > > -- H.J. > > > 0001-x86-Rename-__glibc_reserved1-to-feature_1-in-tcbhead.patch > > > From 600fb331fed5aefc40bd3b95f753ab458b1b796b Mon Sep 17 00:00:00 2001 > From: "H.J. Lu" <hjl.tools@gmail.com> > Date: Thu, 7 Dec 2017 05:47:21 -0800 > Subject: [PATCH 01/24] x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t > [BZ #22563] > > feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET > run-time control. > > CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to > indicate that if CET, IBT and SHSTK are enabled. > > <tls-setup.h> is added to set up thread-local data. > > [BZ #22563] > * nptl/pthread_create.c: Include <tls-setup.h>. > (__pthread_create_2_1): Call tls_setup_tcbhead. > * sysdeps/generic/tls-setup.h: New file. > * sysdeps/x86/nptl/tls-setup.h: Likewise. > * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. > * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): > Likewise. > * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 > to feature_1. > * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. > * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. > (X86_FEATURE_1_SHSTK): Likewise. > (CET_ENABLED): Likewise. > (IBT_ENABLED): Likewise. > (SHSTK_ENABLED): Likewise. > --- > nptl/pthread_create.c | 4 ++++ > sysdeps/generic/tls-setup.h | 22 ++++++++++++++++++++++ > sysdeps/i386/nptl/tcb-offsets.sym | 1 + > sysdeps/i386/nptl/tls.h | 5 ++++- > sysdeps/x86/nptl/tls-setup.h | 23 +++++++++++++++++++++++ > sysdeps/x86/sysdep.h | 27 +++++++++++++++++++++++++++ > sysdeps/x86_64/nptl/tcb-offsets.sym | 1 + > sysdeps/x86_64/nptl/tls.h | 5 ++++- > 8 files changed, 86 insertions(+), 2 deletions(-) > create mode 100644 sysdeps/generic/tls-setup.h > create mode 100644 sysdeps/x86/nptl/tls-setup.h > > diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c > index 92c945b12b..5f5a007b7f 100644 > --- a/nptl/pthread_create.c > +++ b/nptl/pthread_create.c > @@ -32,6 +32,7 @@ > #include <exit-thread.h> > #include <default-sched.h> > #include <futex-internal.h> > +#include <tls-setup.h> > #include "libioP.h" > > #include <shlib-compat.h> > @@ -712,6 +713,9 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, > THREAD_COPY_POINTER_GUARD (pd); > #endif > > + /* Setup tcbhead. */ > + tls_setup_tcbhead (pd); OK. > + > /* Verify the sysinfo bits were copied in allocate_stack if needed. */ > #ifdef NEED_DL_SYSINFO > CHECK_THREAD_SYSINFO (pd); > diff --git a/sysdeps/generic/tls-setup.h b/sysdeps/generic/tls-setup.h > new file mode 100644 > index 0000000000..36389b9bce > --- /dev/null > +++ b/sysdeps/generic/tls-setup.h > @@ -0,0 +1,22 @@ > +/* Definitions to set up thread-local data. Generic version. > + Copyright (C) 2018 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <http://www.gnu.org/licenses/>. */ > + > +static inline void __attribute__ ((always_inline)) > +tls_setup_tcbhead (struct pthread *pd); > +{ > +} > diff --git a/sysdeps/i386/nptl/tcb-offsets.sym b/sysdeps/i386/nptl/tcb-offsets.sym > index 7d7fe5e71c..fbac241c45 100644 > --- a/sysdeps/i386/nptl/tcb-offsets.sym > +++ b/sysdeps/i386/nptl/tcb-offsets.sym > @@ -12,3 +12,4 @@ CLEANUP offsetof (struct pthread, cleanup) > CLEANUP_PREV offsetof (struct _pthread_cleanup_buffer, __prev) > MUTEX_FUTEX offsetof (pthread_mutex_t, __data.__lock) > POINTER_GUARD offsetof (tcbhead_t, pointer_guard) > +FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1) > diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h > index afb71ce431..21e23cd809 100644 > --- a/sysdeps/i386/nptl/tls.h > +++ b/sysdeps/i386/nptl/tls.h > @@ -41,7 +41,10 @@ typedef struct > uintptr_t stack_guard; > uintptr_t pointer_guard; > int gscope_flag; > - int __glibc_reserved1; > + /* Bit 0: X86_FEATURE_1_IBT. > + Bit 1: X86_FEATURE_1_SHSTK. > + */ > + unsigned int feature_1; > /* Reservation of some values for the TM ABI. */ > void *__private_tm[3]; > /* GCC split stack support. */ > diff --git a/sysdeps/x86/nptl/tls-setup.h b/sysdeps/x86/nptl/tls-setup.h > new file mode 100644 > index 0000000000..ef5a4df78c > --- /dev/null > +++ b/sysdeps/x86/nptl/tls-setup.h > @@ -0,0 +1,23 @@ > +/* Definitions to set up thread-local data. x86 version. > + Copyright (C) 2018 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <http://www.gnu.org/licenses/>. */ > + > +static inline void __attribute__ ((always_inline)) > +tls_setup_tcbhead (struct pthread *pd) > +{ > + pd->header.feature_1 = THREAD_GETMEM (THREAD_SELF, header.feature_1); > +} > diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h > index afcb7cfd76..976566aa37 100644 > --- a/sysdeps/x86/sysdep.h > +++ b/sysdeps/x86/sysdep.h > @@ -21,6 +21,33 @@ > > #include <sysdeps/generic/sysdep.h> > > +/* __CET__ is defined by GCC with Control-Flow Protection values: > + > +enum cf_protection_level > +{ > + CF_NONE = 0, > + CF_BRANCH = 1 << 0, > + CF_RETURN = 1 << 1, > + CF_FULL = CF_BRANCH | CF_RETURN, > + CF_SET = 1 << 2 > +}; > +*/ > + > +/* Set if CF_BRANCH (IBT) is enabled. */ > +#define X86_FEATURE_1_IBT (1U << 0) > +/* Set if CF_RETURN (SHSTK) is enabled. */ > +#define X86_FEATURE_1_SHSTK (1U << 1) > + > +#ifdef __CET__ > +# define CET_ENABLED 1 > +# define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT) > +# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK) > +#else > +# define CET_ENABLED 0 > +# define IBT_ENABLED 0 > +# define SHSTK_ENABLED 0 > +#endif > + > #ifdef __ASSEMBLER__ > > /* Syntactic details of assembler. */ > diff --git a/sysdeps/x86_64/nptl/tcb-offsets.sym b/sysdeps/x86_64/nptl/tcb-offsets.sym > index be63404a16..387621e88c 100644 > --- a/sysdeps/x86_64/nptl/tcb-offsets.sym > +++ b/sysdeps/x86_64/nptl/tcb-offsets.sym > @@ -12,6 +12,7 @@ MUTEX_FUTEX offsetof (pthread_mutex_t, __data.__lock) > MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads) > POINTER_GUARD offsetof (tcbhead_t, pointer_guard) > VGETCPU_CACHE_OFFSET offsetof (tcbhead_t, vgetcpu_cache) > +FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1) > > -- Not strictly offsets, but these values are also used in the TCB. > TCB_CANCELSTATE_BITMASK CANCELSTATE_BITMASK > diff --git a/sysdeps/x86_64/nptl/tls.h b/sysdeps/x86_64/nptl/tls.h > index 65c0051dcf..f042a0250a 100644 > --- a/sysdeps/x86_64/nptl/tls.h > +++ b/sysdeps/x86_64/nptl/tls.h > @@ -51,7 +51,10 @@ typedef struct > uintptr_t stack_guard; > uintptr_t pointer_guard; > unsigned long int vgetcpu_cache[2]; > - int __glibc_reserved1; > + /* Bit 0: X86_FEATURE_1_IBT. > + Bit 1: X86_FEATURE_1_SHSTK. > + */ > + unsigned int feature_1; > int __glibc_unused1; > /* Reservation of some values for the TM ABI. */ > void *__private_tm[4]; > -- 2.17.1
From 600fb331fed5aefc40bd3b95f753ab458b1b796b Mon Sep 17 00:00:00 2001 From: "H.J. Lu" <hjl.tools@gmail.com> Date: Thu, 7 Dec 2017 05:47:21 -0800 Subject: [PATCH 01/24] x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t [BZ #22563] feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET run-time control. CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to indicate that if CET, IBT and SHSTK are enabled. <tls-setup.h> is added to set up thread-local data. [BZ #22563] * nptl/pthread_create.c: Include <tls-setup.h>. (__pthread_create_2_1): Call tls_setup_tcbhead. * sysdeps/generic/tls-setup.h: New file. * sysdeps/x86/nptl/tls-setup.h: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): Likewise. * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 to feature_1. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. (X86_FEATURE_1_SHSTK): Likewise. (CET_ENABLED): Likewise. (IBT_ENABLED): Likewise. (SHSTK_ENABLED): Likewise. --- nptl/pthread_create.c | 4 ++++ sysdeps/generic/tls-setup.h | 22 ++++++++++++++++++++++ sysdeps/i386/nptl/tcb-offsets.sym | 1 + sysdeps/i386/nptl/tls.h | 5 ++++- sysdeps/x86/nptl/tls-setup.h | 23 +++++++++++++++++++++++ sysdeps/x86/sysdep.h | 27 +++++++++++++++++++++++++++ sysdeps/x86_64/nptl/tcb-offsets.sym | 1 + sysdeps/x86_64/nptl/tls.h | 5 ++++- 8 files changed, 86 insertions(+), 2 deletions(-) create mode 100644 sysdeps/generic/tls-setup.h create mode 100644 sysdeps/x86/nptl/tls-setup.h diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index 92c945b12b..5f5a007b7f 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -32,6 +32,7 @@ #include <exit-thread.h> #include <default-sched.h> #include <futex-internal.h> +#include <tls-setup.h> #include "libioP.h" #include <shlib-compat.h> @@ -712,6 +713,9 @@ __pthread_create_2_1 (pthread_t *newthread, const pthread_attr_t *attr, THREAD_COPY_POINTER_GUARD (pd); #endif + /* Setup tcbhead. */ + tls_setup_tcbhead (pd); + /* Verify the sysinfo bits were copied in allocate_stack if needed. */ #ifdef NEED_DL_SYSINFO CHECK_THREAD_SYSINFO (pd); diff --git a/sysdeps/generic/tls-setup.h b/sysdeps/generic/tls-setup.h new file mode 100644 index 0000000000..36389b9bce --- /dev/null +++ b/sysdeps/generic/tls-setup.h @@ -0,0 +1,22 @@ +/* Definitions to set up thread-local data. Generic version. + Copyright (C) 2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +static inline void __attribute__ ((always_inline)) +tls_setup_tcbhead (struct pthread *pd); +{ +} diff --git a/sysdeps/i386/nptl/tcb-offsets.sym b/sysdeps/i386/nptl/tcb-offsets.sym index 7d7fe5e71c..fbac241c45 100644 --- a/sysdeps/i386/nptl/tcb-offsets.sym +++ b/sysdeps/i386/nptl/tcb-offsets.sym @@ -12,3 +12,4 @@ CLEANUP offsetof (struct pthread, cleanup) CLEANUP_PREV offsetof (struct _pthread_cleanup_buffer, __prev) MUTEX_FUTEX offsetof (pthread_mutex_t, __data.__lock) POINTER_GUARD offsetof (tcbhead_t, pointer_guard) +FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1) diff --git a/sysdeps/i386/nptl/tls.h b/sysdeps/i386/nptl/tls.h index afb71ce431..21e23cd809 100644 --- a/sysdeps/i386/nptl/tls.h +++ b/sysdeps/i386/nptl/tls.h @@ -41,7 +41,10 @@ typedef struct uintptr_t stack_guard; uintptr_t pointer_guard; int gscope_flag; - int __glibc_reserved1; + /* Bit 0: X86_FEATURE_1_IBT. + Bit 1: X86_FEATURE_1_SHSTK. + */ + unsigned int feature_1; /* Reservation of some values for the TM ABI. */ void *__private_tm[3]; /* GCC split stack support. */ diff --git a/sysdeps/x86/nptl/tls-setup.h b/sysdeps/x86/nptl/tls-setup.h new file mode 100644 index 0000000000..ef5a4df78c --- /dev/null +++ b/sysdeps/x86/nptl/tls-setup.h @@ -0,0 +1,23 @@ +/* Definitions to set up thread-local data. x86 version. + Copyright (C) 2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +static inline void __attribute__ ((always_inline)) +tls_setup_tcbhead (struct pthread *pd) +{ + pd->header.feature_1 = THREAD_GETMEM (THREAD_SELF, header.feature_1); +} diff --git a/sysdeps/x86/sysdep.h b/sysdeps/x86/sysdep.h index afcb7cfd76..976566aa37 100644 --- a/sysdeps/x86/sysdep.h +++ b/sysdeps/x86/sysdep.h @@ -21,6 +21,33 @@ #include <sysdeps/generic/sysdep.h> +/* __CET__ is defined by GCC with Control-Flow Protection values: + +enum cf_protection_level +{ + CF_NONE = 0, + CF_BRANCH = 1 << 0, + CF_RETURN = 1 << 1, + CF_FULL = CF_BRANCH | CF_RETURN, + CF_SET = 1 << 2 +}; +*/ + +/* Set if CF_BRANCH (IBT) is enabled. */ +#define X86_FEATURE_1_IBT (1U << 0) +/* Set if CF_RETURN (SHSTK) is enabled. */ +#define X86_FEATURE_1_SHSTK (1U << 1) + +#ifdef __CET__ +# define CET_ENABLED 1 +# define IBT_ENABLED (__CET__ & X86_FEATURE_1_IBT) +# define SHSTK_ENABLED (__CET__ & X86_FEATURE_1_SHSTK) +#else +# define CET_ENABLED 0 +# define IBT_ENABLED 0 +# define SHSTK_ENABLED 0 +#endif + #ifdef __ASSEMBLER__ /* Syntactic details of assembler. */ diff --git a/sysdeps/x86_64/nptl/tcb-offsets.sym b/sysdeps/x86_64/nptl/tcb-offsets.sym index be63404a16..387621e88c 100644 --- a/sysdeps/x86_64/nptl/tcb-offsets.sym +++ b/sysdeps/x86_64/nptl/tcb-offsets.sym @@ -12,6 +12,7 @@ MUTEX_FUTEX offsetof (pthread_mutex_t, __data.__lock) MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads) POINTER_GUARD offsetof (tcbhead_t, pointer_guard) VGETCPU_CACHE_OFFSET offsetof (tcbhead_t, vgetcpu_cache) +FEATURE_1_OFFSET offsetof (tcbhead_t, feature_1) -- Not strictly offsets, but these values are also used in the TCB. TCB_CANCELSTATE_BITMASK CANCELSTATE_BITMASK diff --git a/sysdeps/x86_64/nptl/tls.h b/sysdeps/x86_64/nptl/tls.h index 65c0051dcf..f042a0250a 100644 --- a/sysdeps/x86_64/nptl/tls.h +++ b/sysdeps/x86_64/nptl/tls.h @@ -51,7 +51,10 @@ typedef struct uintptr_t stack_guard; uintptr_t pointer_guard; unsigned long int vgetcpu_cache[2]; - int __glibc_reserved1; + /* Bit 0: X86_FEATURE_1_IBT. + Bit 1: X86_FEATURE_1_SHSTK. + */ + unsigned int feature_1; int __glibc_unused1; /* Reservation of some values for the TM ABI. */ void *__private_tm[4]; -- 2.17.1