arm64: 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-arm-kernel@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200102172413.654385-3-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This commit is contained in:
Amanieu d'Antras 2020-01-02 18:24:08 +01:00 committed by Christian Brauner
parent 3e3c8ca5a3
commit a4376f2fbc
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2 changed files with 6 additions and 5 deletions

View File

@ -138,6 +138,7 @@ config ARM64
select HAVE_CMPXCHG_DOUBLE
select HAVE_CMPXCHG_LOCAL
select HAVE_CONTEXT_TRACKING
select HAVE_COPY_THREAD_TLS
select HAVE_DEBUG_BUGVERBOSE
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_CONTIGUOUS

View File

@ -360,8 +360,8 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
asmlinkage void ret_from_fork(void) asm("ret_from_fork");
int copy_thread(unsigned long clone_flags, unsigned long stack_start,
unsigned long stk_sz, struct task_struct *p)
int copy_thread_tls(unsigned long clone_flags, unsigned long stack_start,
unsigned long stk_sz, struct task_struct *p, unsigned long tls)
{
struct pt_regs *childregs = task_pt_regs(p);
@ -394,11 +394,11 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
}
/*
* If a TLS pointer was passed to clone (4th argument), use it
* for the new thread.
* If a TLS pointer was passed to clone, use it for the new
* thread.
*/
if (clone_flags & CLONE_SETTLS)
p->thread.uw.tp_value = childregs->regs[3];
p->thread.uw.tp_value = tls;
} else {
memset(childregs, 0, sizeof(struct pt_regs));
childregs->pstate = PSR_MODE_EL1h;