From c19e6d67e4be16e20ff90f0baa98b16d926d23a5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 30 Sep 2012 00:27:40 -0400 Subject: ia64: don't mess with ar_bspstore in kernel_thread() the only thing we use that for is in copy_thread(), where the way we set it will result in rbs_size being 0. Just move that calculating rbs_size and copying rbs to non-kernel-thread side of if (user_mode(regs)) in copy_thread() and set rbs_size to 0 on kernel thread side. Signed-off-by: Al Viro --- arch/ia64/kernel/process.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c index 63a77b8b5cfa..6a48775d9363 100644 --- a/arch/ia64/kernel/process.c +++ b/arch/ia64/kernel/process.c @@ -411,12 +411,11 @@ copy_thread(unsigned long clone_flags, rbs = (unsigned long) current + IA64_RBS_OFFSET; child_rbs = (unsigned long) p + IA64_RBS_OFFSET; - rbs_size = stack->ar_bspstore - rbs; - - /* copy the parent's register backing store to the child: */ - memcpy((void *) child_rbs, (void *) rbs, rbs_size); if (likely(user_mode(child_ptregs))) { + /* copy the parent's register backing store to the child: */ + rbs_size = stack->ar_bspstore - rbs; + memcpy((void *) child_rbs, (void *) rbs, rbs_size); if (clone_flags & CLONE_SETTLS) child_ptregs->r13 = regs->r16; /* see sys_clone2() in entry.S */ if (user_stack_base) { @@ -433,6 +432,7 @@ copy_thread(unsigned long clone_flags, * been taken care of by the caller of sys_clone() * already. */ + rbs_size = 0; child_ptregs->r12 = (unsigned long) child_ptregs - 16; /* kernel sp */ child_ptregs->r13 = (unsigned long) p; /* set `current' pointer */ } @@ -637,7 +637,6 @@ kernel_thread (int (*fn)(void *), void *arg, unsigned long flags) regs.pt.cr_ipsr = ia64_getreg(_IA64_REG_PSR) | IA64_PSR_BN; regs.pt.cr_ifs = 1UL << 63; /* mark as valid, empty frame */ regs.sw.ar_fpsr = regs.pt.ar_fpsr = ia64_getreg(_IA64_REG_AR_FPSR); - regs.sw.ar_bspstore = (unsigned long) current + IA64_RBS_OFFSET; regs.sw.pr = (1 << PRED_KERNEL_STACK); return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s.pt, 0, NULL, NULL); } -- cgit v1.2.3-59-g8ed1b