diff options
| -rw-r--r-- | ChangeLog | 13 | ||||
| -rw-r--r-- | sysdeps/s390/Versions | 4 | ||||
| -rw-r--r-- | sysdeps/s390/dl-tls.h | 35 | ||||
| -rw-r--r-- | sysdeps/s390/s390-32/tls-macros.h | 13 | ||||
| -rw-r--r-- | sysdeps/s390/s390-64/tls-macros.h | 13 |
5 files changed, 60 insertions, 18 deletions
diff --git a/ChangeLog b/ChangeLog index 39e7dfc1ed..6545df25ea 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2013-11-29 Siddhesh Poyarekar <siddhesh@redhat.com> + Andreas Krebbel <Andreas.Krebbel@de.ibm.com> + + [BZ #16214] + * sysdeps/s390/dl-tls.h (__TLS_GET_ADDR): Invoke + __tls_get_addr_internal instead of __tls_get_offset in order to + avoid GOT pointer dependency. Make rtld export + __tls_get_addr_internal@@GLIBC_PRIVATE while still hiding + __tls_get_addr since we are a __tls_get_offset platform. + * sysdeps/s390/s390-64/tls-macros.h (TLS_IE PIC): Don't rely on + GOT pointer being set up before. + * sysdeps/s390/s390-32/tls-macros.h (TLS_IE PIC): Likewise. + 2013-11-28 Joseph Myers <joseph@codesourcery.com> * manual/math.texi (Errors in Math Functions): Document accuracy diff --git a/sysdeps/s390/Versions b/sysdeps/s390/Versions index e18617c399..baf9842eeb 100644 --- a/sysdeps/s390/Versions +++ b/sysdeps/s390/Versions @@ -3,4 +3,8 @@ ld { # runtime interface to TLS __tls_get_offset; } + GLIBC_PRIVATE { + # Exported by ld used by libc. + __tls_get_addr_internal; + } } diff --git a/sysdeps/s390/dl-tls.h b/sysdeps/s390/dl-tls.h index 68a5af4152..52192a26d8 100644 --- a/sysdeps/s390/dl-tls.h +++ b/sysdeps/s390/dl-tls.h @@ -26,11 +26,26 @@ typedef struct #ifdef SHARED -/* This is the prototype for the GNU version. */ -extern void *__tls_get_addr (tls_index *ti) attribute_hidden; + extern unsigned long __tls_get_offset (unsigned long got_offset); # ifdef IS_IN_rtld + +# include <shlib-compat.h> + +extern void *__tls_get_addr (tls_index *ti) attribute_hidden; +/* Make a temporary alias of __tls_get_addr to remove the hidden + attribute. Then export __tls_get_addr as __tls_get_addr_internal + for use from libc. We do not want to export __tls_get_addr, but we + do need to use it from libc when looking up the address of a TLS + variable. We don't use __tls_get_offset because it requires r12 to + be setup and that might not always be true. Either way it's more + optimal to use __tls_get_addr directly (that's what + __tls_get_offset does anyways). */ +strong_alias (__tls_get_addr, __tls_get_addr_internal_tmp); +versioned_symbol (ld, __tls_get_addr_internal_tmp, + __tls_get_addr_internal, GLIBC_PRIVATE); + /* The special thing about the s390 TLS ABI is that we do not have the standard __tls_get_addr function but the __tls_get_offset function which differs in two important aspects: @@ -63,15 +78,21 @@ __tls_get_offset:\n\ 1: .long __tls_get_addr - 0b\n\ "); # endif -# endif +# else /* IS_IN_rtld */ +extern void *__tls_get_addr_internal (tls_index *ti); +# endif /* !IS_IN_rtld */ # define GET_ADDR_OFFSET \ (ti->ti_offset - (unsigned long) __builtin_thread_pointer ()) -# define __TLS_GET_ADDR(__ti) \ - ({ extern char _GLOBAL_OFFSET_TABLE_[] attribute_hidden; \ - (void *) __tls_get_offset ((char *) (__ti) - _GLOBAL_OFFSET_TABLE_) \ - + (unsigned long) __builtin_thread_pointer (); }) +/* Use the privately exported __tls_get_addr_internal instead of + __tls_get_offset in order to avoid the __tls_get_offset special + linkage requiring the GOT pointer to be set up in r12. The + compiler will take care of setting up r12 only if itself issued the + __tls_get_offset call. */ +# define __TLS_GET_ADDR(__ti) \ + ({ (void *) __tls_get_addr_internal ((char *) (__ti)) \ + + (unsigned long) __builtin_thread_pointer (); }) #endif diff --git a/sysdeps/s390/s390-32/tls-macros.h b/sysdeps/s390/s390-32/tls-macros.h index 8a0ad5863c..a592d81585 100644 --- a/sysdeps/s390/s390-32/tls-macros.h +++ b/sysdeps/s390/s390-32/tls-macros.h @@ -8,12 +8,15 @@ #ifdef PIC # define TLS_IE(x) \ - ({ unsigned long __offset; \ + ({ unsigned long __offset, __got; \ asm ("bras %0,1f\n" \ - "0:\t.long " #x "@gotntpoff\n" \ - "1:\tl %0,0(%0)\n\t" \ - "l %0,0(%0,%%r12):tls_load:" #x \ - : "=&a" (__offset) : : "cc" ); \ + "0:\t.long _GLOBAL_OFFSET_TABLE_-0b\n\t" \ + ".long " #x "@gotntpoff\n" \ + "1:\tl %1,0(%0)\n\t" \ + "la %1,0(%1,%0)\n\t" \ + "l %0,4(%0)\n\t" \ + "l %0,0(%0,%1):tls_load:" #x "\n" \ + : "=&a" (__offset), "=&a" (__got) : : "cc" ); \ (int *) (__builtin_thread_pointer() + __offset); }) #else # define TLS_IE(x) \ diff --git a/sysdeps/s390/s390-64/tls-macros.h b/sysdeps/s390/s390-64/tls-macros.h index be8aa6cde0..3c59436341 100644 --- a/sysdeps/s390/s390-64/tls-macros.h +++ b/sysdeps/s390/s390-64/tls-macros.h @@ -8,12 +8,13 @@ #ifdef PIC # define TLS_IE(x) \ - ({ unsigned long __offset; \ - asm ("bras %0,1f\n" \ - "0:\t.quad " #x "@gotntpoff\n" \ - "1:\tlg %0,0(%0)\n\t" \ - "lg %0,0(%0,%%r12):tls_load:" #x \ - : "=&a" (__offset) : : "cc" ); \ + ({ unsigned long __offset, __got; \ + asm ("bras %0,0f\n\t" \ + ".quad " #x "@gotntpoff\n" \ + "0:\tlarl %1,_GLOBAL_OFFSET_TABLE_\n\t" \ + "lg %0,0(%0)\n\t" \ + "lg %0,0(%0,%1):tls_load:" #x "\n" \ + : "=&a" (__offset), "=&a" (__got) : : "cc" ); \ (int *) (__builtin_thread_pointer() + __offset); }) #else # define TLS_IE(x) \ |