From 36ffe7398af5e5daa5745c64a15226d864378738 Mon Sep 17 00:00:00 2001 From: Will Newton Date: Fri, 23 May 2014 15:24:30 +0100 Subject: ARM: Fix handling of concurrent TLS descriptor resolution The current code for handling concurrent resolution says that the ABI for _dl_tlsdesc_resolve_hold is the same as that of _dl_tlsdesc_lazy_resolver. However _dl_tlsdesc_resolve_hold is called from the trampoline directly rather than the lazy resolver stub so, for example, r2 has not been pushed so does not needed to be restored. This fixes an intermittent failure in nptl/tst-tls3 when building glibc for arm-linux-gnueabihf with -mtls-dialect=gnu2. ChangeLog: 2014-05-27 Will Newton [BZ #16990] * sysdeps/arm/dl-tlsdesc.S (_dl_tlsdesc_resolve_hold): Save and restore r2 rather than just restoring. --- ChangeLog | 6 ++++++ NEWS | 2 +- sysdeps/arm/dl-tlsdesc.S | 31 ++++++++++++------------------- 3 files changed, 19 insertions(+), 20 deletions(-) diff --git a/ChangeLog b/ChangeLog index 1c2aff1191..0396d3ba99 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2014-05-27 Will Newton + + [BZ #16990] + * sysdeps/arm/dl-tlsdesc.S (_dl_tlsdesc_resolve_hold): Save + and restore r2 rather than just restoring. + 2014-05-27 Siddhesh Poyarekar [BZ #16724] diff --git a/NEWS b/NEWS index 331601cad9..6a0c222cbd 100644 --- a/NEWS +++ b/NEWS @@ -18,7 +18,7 @@ Version 2.20 16759, 16760, 16770, 16786, 16789, 16791, 16796, 16799, 16800, 16815, 16823, 16824, 16831, 16838, 16849, 16854, 16876, 16877, 16878, 16885, 16888, 16890, 16912, 16915, 16916, 16917, 16922, 16927, 16928, 16932, - 16943, 16958, 16966, 16967, 16965, 16977, 16978, 16984. + 16943, 16958, 16966, 16967, 16965, 16977, 16978, 16984, 16990. * The minimum Linux kernel version that this version of the GNU C Library can be used with is 2.6.32. diff --git a/sysdeps/arm/dl-tlsdesc.S b/sysdeps/arm/dl-tlsdesc.S index 1644a32793..e87e7fb001 100644 --- a/sysdeps/arm/dl-tlsdesc.S +++ b/sysdeps/arm/dl-tlsdesc.S @@ -186,7 +186,9 @@ _dl_tlsdesc_lazy_resolver: .size _dl_tlsdesc_lazy_resolver, .-_dl_tlsdesc_lazy_resolver /* Holder for lazy tls descriptors being resolve in another thread. - Same ABI as the lazy resolver itself. */ + + Our calling convention is to clobber r0, r1 and the processor + flags. All others that are modified must be saved */ .hidden _dl_tlsdesc_resolve_hold .global _dl_tlsdesc_resolve_hold .type _dl_tlsdesc_resolve_hold,#function @@ -194,29 +196,20 @@ _dl_tlsdesc_lazy_resolver: eabi_fnstart .align 2 _dl_tlsdesc_resolve_hold: - /* Tell the unwinder that r2 has already been pushed. */ - eabi_save ({r2}) - cfi_adjust_cfa_offset (4) + eabi_save ({r2,r3,ip,lr}) + push {r2, r3, ip, lr} + cfi_adjust_cfa_offset (16) cfi_rel_offset (r2, 0) - eabi_save ({r0,r1,r3,ip,lr}) - push {r0, r1, r3, ip, lr} - cfi_adjust_cfa_offset (20) - cfi_rel_offset (r0, 0) - cfi_rel_offset (r1, 4) - cfi_rel_offset (r3, 8) - cfi_rel_offset (ip, 12) - cfi_rel_offset (lr, 16) - adr r2, _dl_tlsdesc_resolve_hold + cfi_rel_offset (r3, 4) + cfi_rel_offset (ip, 8) + cfi_rel_offset (lr, 12) + adr r1, _dl_tlsdesc_resolve_hold bl _dl_tlsdesc_resolve_hold_fixup - pop {r0, r1, r3, ip, lr} - cfi_adjust_cfa_offset (-20) + pop {r2, r3, ip, lr} + cfi_adjust_cfa_offset (-16) cfi_restore (lr) cfi_restore (ip) cfi_restore (r3) - cfi_restore (r1) - cfi_restore (r0) - pop {r2} - cfi_adjust_cfa_offset (-4) cfi_restore (r2) sfi_breg r0, \ ldr r1, [\B, #4] -- cgit 1.4.1