From: Christian Svensson <b...@cmd.nu>

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 <b...@cmd.nu>
Signed-off-by: Stefan Kristiansson <stefan.kristians...@saunalahti.fi>
Signed-off-by: Stafford Horne <sho...@gmail.com>
---
 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

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