From 18173559a23e28055640b152e623d9f0d40ecca8 Mon Sep 17 00:00:00 2001 From: "Paul E. Murphy" Date: Fri, 21 Aug 2015 14:39:01 -0500 Subject: [PATCH] powerpc: Fix tabort usage in syscalls Fix usage of tabort in generated syscalls. r0 has special meaning when used with this instruction, thus it will not generate persistent errors, nor return an error code. This mitigates poor CPU usage when performing elided critical sections. Additionally, transactions should be aborted when entering a user invoked syscall. Otherwise the results of the transaction may be undefined. 2015-08-25 Paul E. Murphy * sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION): Use register other than r0 for tabort, it has special meaning. * sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION): Likewise * sysdeps/unix.sysv/linux/powerpc/syscall.S (syscall): Abort transaction before starting syscall. --- ChangeLog | 8 ++++++++ sysdeps/powerpc/powerpc32/sysdep.h | 4 ++-- sysdeps/powerpc/powerpc64/sysdep.h | 4 ++-- sysdeps/unix/sysv/linux/powerpc/syscall.S | 1 + 4 files changed, 13 insertions(+), 4 deletions(-) diff --git a/ChangeLog b/ChangeLog index 13fc3fb98a..6e55d886a6 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2015-08-25 Paul E. Murphy + + * sysdeps/powerpc/powerpc32/sysdep.h (ABORT_TRANSACTION): Use + register other than r0 for tabort, it has special meaning. + * sysdeps/powerpc/powerpc64/sysdep.h (ABORT_TRANSACTION): Likewise + * sysdeps/unix.sysv/linux/powerpc/syscall.S (syscall): Abort + transaction before starting syscall. + 2015-08-25 Rajalakshmi Srinivasaraghavan * sysdeps/powerpc/powerpc64/power7/strstr.S: Handle worst case. diff --git a/sysdeps/powerpc/powerpc32/sysdep.h b/sysdeps/powerpc/powerpc32/sysdep.h index e16fe3e224..ecb492a5ab 100644 --- a/sysdeps/powerpc/powerpc32/sysdep.h +++ b/sysdeps/powerpc/powerpc32/sysdep.h @@ -95,8 +95,8 @@ GOT_LABEL: ; \ lwz 0,TM_CAPABLE(2); \ cmpwi 0,0; \ beq 1f; \ - li 0,_ABORT_SYSCALL; \ - tabort. 0; \ + li 11,_ABORT_SYSCALL; \ + tabort. 11; \ .align 4; \ 1: #else diff --git a/sysdeps/powerpc/powerpc64/sysdep.h b/sysdeps/powerpc/powerpc64/sysdep.h index bf2a884b99..a9d37ad437 100644 --- a/sysdeps/powerpc/powerpc64/sysdep.h +++ b/sysdeps/powerpc/powerpc64/sysdep.h @@ -279,8 +279,8 @@ LT_LABELSUFFIX(name,_name_end): ; \ lwz 0,TM_CAPABLE(13); \ cmpwi 0,0; \ beq 1f; \ - li 0,_ABORT_SYSCALL; \ - tabort. 0; \ + li 11,_ABORT_SYSCALL; \ + tabort. 11; \ .align 4; \ 1: #else diff --git a/sysdeps/unix/sysv/linux/powerpc/syscall.S b/sysdeps/unix/sysv/linux/powerpc/syscall.S index 157e3e3296..44773038bc 100644 --- a/sysdeps/unix/sysv/linux/powerpc/syscall.S +++ b/sysdeps/unix/sysv/linux/powerpc/syscall.S @@ -18,6 +18,7 @@ #include ENTRY (syscall) + ABORT_TRANSACTION mr r0,r3 mr r3,r4 mr r4,r5 -- 2.11.4.GIT