diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2012-09-30 06:27:40 +0200 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-10-15 01:33:54 +0200 |
| commit | c19e6d67e4be16e20ff90f0baa98b16d926d23a5 (patch) | |
| tree | c5421d406815c7341c26179acf8b71bdaf251a18 /arch/ia64/kernel/process.c | |
| parent | ia64: dead code in copy_thread() since 2004 (diff) | |
| download | linux-c19e6d67e4be16e20ff90f0baa98b16d926d23a5.tar.xz linux-c19e6d67e4be16e20ff90f0baa98b16d926d23a5.zip | |
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 <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/ia64/kernel/process.c')
| -rw-r--r-- | arch/ia64/kernel/process.c | 9 |
1 files changed, 4 insertions, 5 deletions
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); } |