| Message ID | 1518026313-22248-1-git-send-email-adhemerval.zanella@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | aarch64: Add split-stack TCB field | expand |
On Wed, 7 Feb 2018, Adhemerval Zanella wrote: > * sysdeps/aarch64/Versions [ld] (GLIBC_2.26): Add > __libc_tcb_private_ss. This ChangeLog entry is out of date compared to current symbol versions. > diff --git a/sysdeps/aarch64/tcb-version.c b/sysdeps/aarch64/tcb-version.c > new file mode 100644 > index 0000000..c94e5d3 > --- /dev/null > +++ b/sysdeps/aarch64/tcb-version.c > @@ -0,0 +1,23 @@ > +/* TCB field abi advertise symbols. > + Copyright (C) 2017 Free Software Foundation, Inc. Should now be 2017-2018. -- Joseph S. Myers joseph@codesourcery.com
On 07/02/2018 16:04, Joseph Myers wrote: > On Wed, 7 Feb 2018, Adhemerval Zanella wrote: > >> * sysdeps/aarch64/Versions [ld] (GLIBC_2.26): Add >> __libc_tcb_private_ss. > > This ChangeLog entry is out of date compared to current symbol versions. > >> diff --git a/sysdeps/aarch64/tcb-version.c b/sysdeps/aarch64/tcb-version.c >> new file mode 100644 >> index 0000000..c94e5d3 >> --- /dev/null >> +++ b/sysdeps/aarch64/tcb-version.c >> @@ -0,0 +1,23 @@ >> +/* TCB field abi advertise symbols. >> + Copyright (C) 2017 Free Software Foundation, Inc. > > Should now be 2017-2018. > Thanks I fixed it locally.
On 07/02/18 17:58, Adhemerval Zanella wrote: > This patch adds split-stack support pointer guard on glibc for aarch64. > Different from other architectures (powerpc, s390) where the memory is > placed on TCB, aarch64 one is placed before thread pointer initial > position. It has an advantage over extending TCB because for aarch64 > TLS variable placement take in consideration tcbhead_t size and by > changing its value would require to also update the static linker > (and it would also add incompatibility with glibc and older linkers). > > For aarch64 tcb direct access is fastest for thread local variable on > all mode and related TLS access. It requires just a direct load with > displacement of -8 (since thread pointer points to tcbhead_t). > > It also adds a loader symbol (__tcb_private_ss) to signal the existence __libc_tcb_private_ss > of the split stack guard area. > > Checked on aarch64-linux-gnu. > > * sysdeps/aarch64/Makefile [$(subdir) = elf] (sysdeps-dl-routines): > Add tcb-version. > * sysdeps/aarch64/Versions [ld] (GLIBC_2.26): Add > __libc_tcb_private_ss. > * sysdeps/aarch64/nptl/tls.h (tcbprehead_t): New struct. > (TLS_PRE_TCB_SIZE): Take tcbprehead_t in consideration. > (TLS_DEFINE_INIT_TP): Likewise. > (THREAD_SELF): Likewise. > (DB_THREAD_SELF): Likewise. > * sysdeps/aarch64/tcb-version.c: New file. > * sysdeps/unix/sysv/linux/aarch64/ld.abilist (GLIBC_2.26): Add. > (__libc_tcb_private_ss): Likewise. > * sysdeps/aarch64/nptl/tcb-offsets.sym (PTHREAD_SIZEOF): Rename to > PTHREAD_PRE_TCB_SIZE. i don't see where PTHREAD_PRE_TCB_SIZE is used (or PTHREAD_SIZEOF) > --- > ChangeLog | 17 +++++++++++++++++ > sysdeps/aarch64/Makefile | 2 +- > sysdeps/aarch64/Versions | 8 ++++++++ > sysdeps/aarch64/nptl/tcb-offsets.sym | 2 +- > sysdeps/aarch64/nptl/tls.h | 25 ++++++++++++++++++++----- > sysdeps/aarch64/tcb-version.c | 23 +++++++++++++++++++++++ > sysdeps/unix/sysv/linux/aarch64/ld.abilist | 2 ++ > 7 files changed, 72 insertions(+), 7 deletions(-) > create mode 100644 sysdeps/aarch64/tcb-version.c > > diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile > index 5f3e203..141442a 100644 > --- a/sysdeps/aarch64/Makefile > +++ b/sysdeps/aarch64/Makefile > @@ -1,7 +1,7 @@ > long-double-fcts = yes > > ifeq ($(subdir),elf) > -sysdep-dl-routines += tlsdesc dl-tlsdesc > +sysdep-dl-routines += tlsdesc dl-tlsdesc tcb-version > gen-as-const-headers += dl-link.sym > endif > > diff --git a/sysdeps/aarch64/Versions b/sysdeps/aarch64/Versions > index e1aa44f..dcc395c 100644 > --- a/sysdeps/aarch64/Versions > +++ b/sysdeps/aarch64/Versions > @@ -3,3 +3,11 @@ libc { > _mcount; > } > } > + > +ld { > + GLIBC_2.28 { > + # Symbol used to version control the private GLIBC TCB split-stack > + # field. > + __libc_tcb_private_ss; > + } > +} > diff --git a/sysdeps/aarch64/nptl/tcb-offsets.sym b/sysdeps/aarch64/nptl/tcb-offsets.sym > index 238647d..6004379 100644 > --- a/sysdeps/aarch64/nptl/tcb-offsets.sym > +++ b/sysdeps/aarch64/nptl/tcb-offsets.sym > @@ -3,4 +3,4 @@ > > PTHREAD_MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads) > PTHREAD_TID_OFFSET offsetof (struct pthread, tid) > -PTHREAD_SIZEOF sizeof (struct pthread) > +PTHREAD_PRE_TCB_SIZE TLS_PRE_TCB_SIZE > diff --git a/sysdeps/aarch64/nptl/tls.h b/sysdeps/aarch64/nptl/tls.h > index ac39c24..2d88310 100644 > --- a/sysdeps/aarch64/nptl/tls.h > +++ b/sysdeps/aarch64/nptl/tls.h > @@ -26,6 +26,7 @@ > # include <stddef.h> > # include <stdint.h> > # include <dl-dtv.h> > +# include <libc-pointer-arith.h> > > #else /* __ASSEMBLER__ */ > # include <tcb-offsets.h> > @@ -49,6 +50,12 @@ typedef struct > void *private; > } tcbhead_t; > > +typedef struct > +{ > + /* GCC split stack support. */ > + void *__private_ss; > +} tcbprehead_t; > + > /* This is the size of the initial TCB. */ > # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) > > @@ -58,8 +65,14 @@ typedef struct > /* This is the size of the TCB. */ > # define TLS_TCB_SIZE sizeof (tcbhead_t) > > -/* This is the size we need before TCB. */ > -# define TLS_PRE_TCB_SIZE sizeof (struct pthread) > +/* This is the size we need before TCB. Check if there is room for > + tcbprehead_t in struct pthread's final padding and if not add it on > + required pre-tcb size. */ > +# define TLS_PRE_TCB_SIZE \ > + (sizeof (struct pthread) \ > + + (PTHREAD_STRUCT_END_PADDING < sizeof (tcbprehead_t) \ > + ? ALIGN_UP (sizeof (tcbprehead_t), __alignof__ (struct pthread)) \ > + : 0)) > it looks ok, but a bit ugly, i don't see a clean way to express the requirements in c. if i understand correctly the tls layout is struct pthread tcbprehead_t tcbhead_t static tls <--------------><-------------><----------><-----------> ^ TP where tcbprehead_t may overlap with paddings at the end of struct pthread. and we have to make sure offsets from TP to the members of tcbprehead_t don't change. i think there should be a comment about this layout and the alignment/offset requirements somewhere in tls.h (so next time it's easier to allocate such a tls slot) > /* Alignment requirements for the TCB. */ > # define TLS_TCB_ALIGN __alignof__ (struct pthread) > @@ -84,7 +97,8 @@ typedef struct > ({ __asm __volatile ("msr tpidr_el0, %0" : : "r" (tcbp)); NULL; }) > > /* Value passed to 'clone' for initialization of the thread register. */ > -# define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1 > +# define TLS_DEFINE_INIT_TP(tp, pd) \ > + void *tp = (void*)((uintptr_t) (pd) + TLS_PRE_TCB_SIZE) > > /* Return the address of the dtv for the current thread. */ > # define THREAD_DTV() \ > @@ -92,11 +106,12 @@ typedef struct > > /* Return the thread descriptor for the current thread. */ > # define THREAD_SELF \ > - ((struct pthread *)__builtin_thread_pointer () - 1) > + ((struct pthread *)((uintptr_t) __builtin_thread_pointer () \ > + - TLS_PRE_TCB_SIZE)) > > /* Magic for libthread_db to know how to do THREAD_SELF. */ > # define DB_THREAD_SELF \ > - CONST_THREAD_AREA (64, sizeof (struct pthread)) > + CONST_THREAD_AREA (64, TLS_PRE_TCB_SIZE) > > /* Access to data in the thread descriptor is easy. */ > # define THREAD_GETMEM(descr, member) \ > diff --git a/sysdeps/aarch64/tcb-version.c b/sysdeps/aarch64/tcb-version.c > new file mode 100644 > index 0000000..c94e5d3 > --- /dev/null > +++ b/sysdeps/aarch64/tcb-version.c > @@ -0,0 +1,23 @@ > +/* TCB field abi advertise symbols. > + Copyright (C) 2017 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/>. */ > + > +#include <libc-internal.h> > + > +/* Symbol used to version control the private GLIBC TCB split-stack > + field. */ > +long int attribute_relro __libc_tcb_private_ss; > diff --git a/sysdeps/unix/sysv/linux/aarch64/ld.abilist b/sysdeps/unix/sysv/linux/aarch64/ld.abilist > index ec7f617..aaddb24 100644 > --- a/sysdeps/unix/sysv/linux/aarch64/ld.abilist > +++ b/sysdeps/unix/sysv/linux/aarch64/ld.abilist > @@ -8,3 +8,5 @@ GLIBC_2.17 calloc F > GLIBC_2.17 free F > GLIBC_2.17 malloc F > GLIBC_2.17 realloc F > +GLIBC_2.28 GLIBC_2.28 A > +GLIBC_2.28 __libc_tcb_private_ss D 0x8 >
On 13/02/2018 14:56, Szabolcs Nagy wrote: > On 07/02/18 17:58, Adhemerval Zanella wrote: >> This patch adds split-stack support pointer guard on glibc for aarch64. >> Different from other architectures (powerpc, s390) where the memory is >> placed on TCB, aarch64 one is placed before thread pointer initial >> position. It has an advantage over extending TCB because for aarch64 >> TLS variable placement take in consideration tcbhead_t size and by >> changing its value would require to also update the static linker >> (and it would also add incompatibility with glibc and older linkers). >> >> For aarch64 tcb direct access is fastest for thread local variable on >> all mode and related TLS access. It requires just a direct load with >> displacement of -8 (since thread pointer points to tcbhead_t). >> >> It also adds a loader symbol (__tcb_private_ss) to signal the existence > > __libc_tcb_private_ss Fixed locally. > >> of the split stack guard area. >> >> Checked on aarch64-linux-gnu. >> >> * sysdeps/aarch64/Makefile [$(subdir) = elf] (sysdeps-dl-routines): >> Add tcb-version. >> * sysdeps/aarch64/Versions [ld] (GLIBC_2.26): Add >> __libc_tcb_private_ss. >> * sysdeps/aarch64/nptl/tls.h (tcbprehead_t): New struct. >> (TLS_PRE_TCB_SIZE): Take tcbprehead_t in consideration. >> (TLS_DEFINE_INIT_TP): Likewise. >> (THREAD_SELF): Likewise. >> (DB_THREAD_SELF): Likewise. >> * sysdeps/aarch64/tcb-version.c: New file. >> * sysdeps/unix/sysv/linux/aarch64/ld.abilist (GLIBC_2.26): Add. >> (__libc_tcb_private_ss): Likewise. >> * sysdeps/aarch64/nptl/tcb-offsets.sym (PTHREAD_SIZEOF): Rename to >> PTHREAD_PRE_TCB_SIZE. > > i don't see where PTHREAD_PRE_TCB_SIZE is used > (or PTHREAD_SIZEOF) Indeed, it is an artefact from previous version. I removed it in the patch below. >> diff --git a/sysdeps/aarch64/nptl/tls.h b/sysdeps/aarch64/nptl/tls.h >> index ac39c24..2d88310 100644 >> --- a/sysdeps/aarch64/nptl/tls.h >> +++ b/sysdeps/aarch64/nptl/tls.h >> @@ -26,6 +26,7 @@ >> # include <stddef.h> >> # include <stdint.h> >> # include <dl-dtv.h> >> +# include <libc-pointer-arith.h> >> #else /* __ASSEMBLER__ */ >> # include <tcb-offsets.h> >> @@ -49,6 +50,12 @@ typedef struct >> void *private; >> } tcbhead_t; >> +typedef struct >> +{ >> + /* GCC split stack support. */ >> + void *__private_ss; >> +} tcbprehead_t; >> + >> /* This is the size of the initial TCB. */ >> # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) >> @@ -58,8 +65,14 @@ typedef struct >> /* This is the size of the TCB. */ >> # define TLS_TCB_SIZE sizeof (tcbhead_t) >> -/* This is the size we need before TCB. */ >> -# define TLS_PRE_TCB_SIZE sizeof (struct pthread) >> +/* This is the size we need before TCB. Check if there is room for >> + tcbprehead_t in struct pthread's final padding and if not add it on >> + required pre-tcb size. */ >> +# define TLS_PRE_TCB_SIZE \ >> + (sizeof (struct pthread) \ >> + + (PTHREAD_STRUCT_END_PADDING < sizeof (tcbprehead_t) \ >> + ? ALIGN_UP (sizeof (tcbprehead_t), __alignof__ (struct pthread)) \ >> + : 0)) >> > > it looks ok, but a bit ugly, i don't see a clean way > to express the requirements in c. > > if i understand correctly the tls layout is > > struct pthread tcbprehead_t tcbhead_t static tls > <--------------><-------------><----------><-----------> > ^ > TP > > where tcbprehead_t may overlap with paddings at the end > of struct pthread. > > and we have to make sure offsets from TP to the members > of tcbprehead_t don't change. > > i think there should be a comment about this layout and > the alignment/offset requirements somewhere in tls.h > (so next time it's easier to allocate such a tls slot) I have added a comment about the layout and possible newer member additions on tcbprehead_t. -- * sysdeps/aarch64/Makefile [$(subdir) = elf] (sysdeps-dl-routines): Add tcb-version. * sysdeps/aarch64/Versions [ld] (GLIBC_2.28): Add __libc_tcb_private_ss. * sysdeps/aarch64/nptl/tls.h (tcbprehead_t): New struct. (TLS_PRE_TCB_SIZE): Take tcbprehead_t in consideration. (TLS_DEFINE_INIT_TP): Likewise. (THREAD_SELF): Likewise. (DB_THREAD_SELF): Likewise. * sysdeps/aarch64/tcb-version.c: New file. * sysdeps/unix/sysv/linux/aarch64/ld.abilist (GLIBC_2.28): Add. (__libc_tcb_private_ss): Likewise. --- diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile index 5f3e203..141442a 100644 --- a/sysdeps/aarch64/Makefile +++ b/sysdeps/aarch64/Makefile @@ -1,7 +1,7 @@ long-double-fcts = yes ifeq ($(subdir),elf) -sysdep-dl-routines += tlsdesc dl-tlsdesc +sysdep-dl-routines += tlsdesc dl-tlsdesc tcb-version gen-as-const-headers += dl-link.sym endif diff --git a/sysdeps/aarch64/Versions b/sysdeps/aarch64/Versions index e1aa44f..dcc395c 100644 --- a/sysdeps/aarch64/Versions +++ b/sysdeps/aarch64/Versions @@ -3,3 +3,11 @@ libc { _mcount; } } + +ld { + GLIBC_2.28 { + # Symbol used to version control the private GLIBC TCB split-stack + # field. + __libc_tcb_private_ss; + } +} diff --git a/sysdeps/aarch64/nptl/tls.h b/sysdeps/aarch64/nptl/tls.h index ac39c24..99606d0 100644 --- a/sysdeps/aarch64/nptl/tls.h +++ b/sysdeps/aarch64/nptl/tls.h @@ -26,6 +26,7 @@ # include <stddef.h> # include <stdint.h> # include <dl-dtv.h> +# include <libc-pointer-arith.h> #else /* __ASSEMBLER__ */ # include <tcb-offsets.h> @@ -43,12 +44,32 @@ /* Get the thread descriptor definition. */ # include <nptl/descr.h> +/* The resulting TLS layout is: + + |----------------|--------------|-----------|------------| + | struct pthread | tcbprehead_t | tcbhead_t | static tls | + |----------------|--------------|-----------|------------| + \_ Thread pointer + + And tcbprehead_t might overlap the padding at the end of the + struct pthread, otherwise extra space is allocated (check TLS_PRE_TCB_SIZE + definition). + + Additional fields on tcbhead_t must keep member offset constant (so they + should be added at the beggining of the struct). */ + typedef struct { dtv_t *dtv; void *private; } tcbhead_t; +typedef struct +{ + /* GCC split stack support. */ + void *__private_ss; +} tcbprehead_t; + /* This is the size of the initial TCB. */ # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) @@ -58,8 +79,14 @@ typedef struct /* This is the size of the TCB. */ # define TLS_TCB_SIZE sizeof (tcbhead_t) -/* This is the size we need before TCB. */ -# define TLS_PRE_TCB_SIZE sizeof (struct pthread) +/* This is the size we need before TCB. Check if there is room for + tcbprehead_t in struct pthread's final padding and if not add it on + required pre-tcb size. */ +# define TLS_PRE_TCB_SIZE \ + (sizeof (struct pthread) \ + + (PTHREAD_STRUCT_END_PADDING < sizeof (tcbprehead_t) \ + ? ALIGN_UP (sizeof (tcbprehead_t), __alignof__ (struct pthread)) \ + : 0)) /* Alignment requirements for the TCB. */ # define TLS_TCB_ALIGN __alignof__ (struct pthread) @@ -84,7 +111,8 @@ typedef struct ({ __asm __volatile ("msr tpidr_el0, %0" : : "r" (tcbp)); NULL; }) /* Value passed to 'clone' for initialization of the thread register. */ -# define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1 +# define TLS_DEFINE_INIT_TP(tp, pd) \ + void *tp = (void*)((uintptr_t) (pd) + TLS_PRE_TCB_SIZE) /* Return the address of the dtv for the current thread. */ # define THREAD_DTV() \ @@ -92,11 +120,12 @@ typedef struct /* Return the thread descriptor for the current thread. */ # define THREAD_SELF \ - ((struct pthread *)__builtin_thread_pointer () - 1) + ((struct pthread *)((uintptr_t) __builtin_thread_pointer () \ + - TLS_PRE_TCB_SIZE)) /* Magic for libthread_db to know how to do THREAD_SELF. */ # define DB_THREAD_SELF \ - CONST_THREAD_AREA (64, sizeof (struct pthread)) + CONST_THREAD_AREA (64, TLS_PRE_TCB_SIZE) /* Access to data in the thread descriptor is easy. */ # define THREAD_GETMEM(descr, member) \ diff --git a/sysdeps/aarch64/tcb-version.c b/sysdeps/aarch64/tcb-version.c new file mode 100644 index 0000000..eaa75dd --- /dev/null +++ b/sysdeps/aarch64/tcb-version.c @@ -0,0 +1,23 @@ +/* TCB field abi advertise symbols. + Copyright (C) 2017-2018 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/>. */ + +#include <libc-internal.h> + +/* Symbol used to version control the private GLIBC TCB split-stack + field. */ +long int attribute_relro __libc_tcb_private_ss; diff --git a/sysdeps/unix/sysv/linux/aarch64/ld.abilist b/sysdeps/unix/sysv/linux/aarch64/ld.abilist index ec7f617..aaddb24 100644 --- a/sysdeps/unix/sysv/linux/aarch64/ld.abilist +++ b/sysdeps/unix/sysv/linux/aarch64/ld.abilist @@ -8,3 +8,5 @@ GLIBC_2.17 calloc F GLIBC_2.17 free F GLIBC_2.17 malloc F GLIBC_2.17 realloc F +GLIBC_2.28 GLIBC_2.28 A +GLIBC_2.28 __libc_tcb_private_ss D 0x8
diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile index 5f3e203..141442a 100644 --- a/sysdeps/aarch64/Makefile +++ b/sysdeps/aarch64/Makefile @@ -1,7 +1,7 @@ long-double-fcts = yes ifeq ($(subdir),elf) -sysdep-dl-routines += tlsdesc dl-tlsdesc +sysdep-dl-routines += tlsdesc dl-tlsdesc tcb-version gen-as-const-headers += dl-link.sym endif diff --git a/sysdeps/aarch64/Versions b/sysdeps/aarch64/Versions index e1aa44f..dcc395c 100644 --- a/sysdeps/aarch64/Versions +++ b/sysdeps/aarch64/Versions @@ -3,3 +3,11 @@ libc { _mcount; } } + +ld { + GLIBC_2.28 { + # Symbol used to version control the private GLIBC TCB split-stack + # field. + __libc_tcb_private_ss; + } +} diff --git a/sysdeps/aarch64/nptl/tcb-offsets.sym b/sysdeps/aarch64/nptl/tcb-offsets.sym index 238647d..6004379 100644 --- a/sysdeps/aarch64/nptl/tcb-offsets.sym +++ b/sysdeps/aarch64/nptl/tcb-offsets.sym @@ -3,4 +3,4 @@ PTHREAD_MULTIPLE_THREADS_OFFSET offsetof (struct pthread, header.multiple_threads) PTHREAD_TID_OFFSET offsetof (struct pthread, tid) -PTHREAD_SIZEOF sizeof (struct pthread) +PTHREAD_PRE_TCB_SIZE TLS_PRE_TCB_SIZE diff --git a/sysdeps/aarch64/nptl/tls.h b/sysdeps/aarch64/nptl/tls.h index ac39c24..2d88310 100644 --- a/sysdeps/aarch64/nptl/tls.h +++ b/sysdeps/aarch64/nptl/tls.h @@ -26,6 +26,7 @@ # include <stddef.h> # include <stdint.h> # include <dl-dtv.h> +# include <libc-pointer-arith.h> #else /* __ASSEMBLER__ */ # include <tcb-offsets.h> @@ -49,6 +50,12 @@ typedef struct void *private; } tcbhead_t; +typedef struct +{ + /* GCC split stack support. */ + void *__private_ss; +} tcbprehead_t; + /* This is the size of the initial TCB. */ # define TLS_INIT_TCB_SIZE sizeof (tcbhead_t) @@ -58,8 +65,14 @@ typedef struct /* This is the size of the TCB. */ # define TLS_TCB_SIZE sizeof (tcbhead_t) -/* This is the size we need before TCB. */ -# define TLS_PRE_TCB_SIZE sizeof (struct pthread) +/* This is the size we need before TCB. Check if there is room for + tcbprehead_t in struct pthread's final padding and if not add it on + required pre-tcb size. */ +# define TLS_PRE_TCB_SIZE \ + (sizeof (struct pthread) \ + + (PTHREAD_STRUCT_END_PADDING < sizeof (tcbprehead_t) \ + ? ALIGN_UP (sizeof (tcbprehead_t), __alignof__ (struct pthread)) \ + : 0)) /* Alignment requirements for the TCB. */ # define TLS_TCB_ALIGN __alignof__ (struct pthread) @@ -84,7 +97,8 @@ typedef struct ({ __asm __volatile ("msr tpidr_el0, %0" : : "r" (tcbp)); NULL; }) /* Value passed to 'clone' for initialization of the thread register. */ -# define TLS_DEFINE_INIT_TP(tp, pd) void *tp = (pd) + 1 +# define TLS_DEFINE_INIT_TP(tp, pd) \ + void *tp = (void*)((uintptr_t) (pd) + TLS_PRE_TCB_SIZE) /* Return the address of the dtv for the current thread. */ # define THREAD_DTV() \ @@ -92,11 +106,12 @@ typedef struct /* Return the thread descriptor for the current thread. */ # define THREAD_SELF \ - ((struct pthread *)__builtin_thread_pointer () - 1) + ((struct pthread *)((uintptr_t) __builtin_thread_pointer () \ + - TLS_PRE_TCB_SIZE)) /* Magic for libthread_db to know how to do THREAD_SELF. */ # define DB_THREAD_SELF \ - CONST_THREAD_AREA (64, sizeof (struct pthread)) + CONST_THREAD_AREA (64, TLS_PRE_TCB_SIZE) /* Access to data in the thread descriptor is easy. */ # define THREAD_GETMEM(descr, member) \ diff --git a/sysdeps/aarch64/tcb-version.c b/sysdeps/aarch64/tcb-version.c new file mode 100644 index 0000000..c94e5d3 --- /dev/null +++ b/sysdeps/aarch64/tcb-version.c @@ -0,0 +1,23 @@ +/* TCB field abi advertise symbols. + Copyright (C) 2017 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/>. */ + +#include <libc-internal.h> + +/* Symbol used to version control the private GLIBC TCB split-stack + field. */ +long int attribute_relro __libc_tcb_private_ss; diff --git a/sysdeps/unix/sysv/linux/aarch64/ld.abilist b/sysdeps/unix/sysv/linux/aarch64/ld.abilist index ec7f617..aaddb24 100644 --- a/sysdeps/unix/sysv/linux/aarch64/ld.abilist +++ b/sysdeps/unix/sysv/linux/aarch64/ld.abilist @@ -8,3 +8,5 @@ GLIBC_2.17 calloc F GLIBC_2.17 free F GLIBC_2.17 malloc F GLIBC_2.17 realloc F +GLIBC_2.28 GLIBC_2.28 A +GLIBC_2.28 __libc_tcb_private_ss D 0x8