From: Christian Svensson <[email protected]> Historically OpenRISC GCC has reserved r10 which we now use to hold the thread pointer for thread-local storage (TLS).
Signed-off-by: Christian Svensson <[email protected]> Signed-off-by: Stefan Kristiansson <[email protected]> Signed-off-by: Stafford Horne <[email protected]> --- arch/openrisc/kernel/process.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/openrisc/kernel/process.c b/arch/openrisc/kernel/process.c index 7095dfe..277123b 100644 --- a/arch/openrisc/kernel/process.c +++ b/arch/openrisc/kernel/process.c @@ -173,6 +173,19 @@ copy_thread(unsigned long clone_flags, unsigned long usp, if (usp) userregs->sp = usp; + + /* + * For CLONE_SETTLS set "tp" (r10) to the TLS pointer passed to sys_clone. + * + * The kernel entry is: + * int clone (long flags, void *child_stack, int *parent_tid, + * int *child_tid, struct void *tls) + * + * This makes the source r7 in the kernel registers. + */ + if (clone_flags & CLONE_SETTLS) + userregs->gpr[10] = userregs->gpr[7]; + userregs->gpr[11] = 0; /* Result from fork() */ kregs->gpr[20] = 0; /* Userspace thread */ -- 2.7.4
