xtensa: Implement copy_thread_tls

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-7-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This commit is contained in:
Amanieu d'Antras 2020-01-02 18:24:12 +01:00 committed by Christian Brauner
parent 20bda4ed62
commit c346b94f8c
No known key found for this signature in database
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2 changed files with 5 additions and 4 deletions

View File

@ -24,6 +24,7 @@ config XTENSA
select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
select HAVE_ARCH_TRACEHOOK
select HAVE_COPY_THREAD_TLS
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_CONTIGUOUS
select HAVE_EXIT_THREAD

View File

@ -202,8 +202,9 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
* involved. Much simpler to just not copy those live frames across.
*/
int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
unsigned long thread_fn_arg, struct task_struct *p)
int copy_thread_tls(unsigned long clone_flags, unsigned long usp_thread_fn,
unsigned long thread_fn_arg, struct task_struct *p,
unsigned long tls)
{
struct pt_regs *childregs = task_pt_regs(p);
@ -266,9 +267,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn,
childregs->syscall = regs->syscall;
/* The thread pointer is passed in the '4th argument' (= a5) */
if (clone_flags & CLONE_SETTLS)
childregs->threadptr = childregs->areg[5];
childregs->threadptr = tls;
} else {
p->thread.ra = MAKE_RA_FOR_CALL(
(unsigned long)ret_from_kernel_thread, 1);