diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-08-19 21:23:48 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-08-21 13:55:49 +0100 |
| commit | 1eef5d2f1b461c120bcd82077edee5ec706ac53b (patch) | |
| tree | b95a7132189a44d9a826e7b44fbbe5cae74d75fb /arch/arm/kernel/process.c | |
| parent | d770e558e21961ad6cfdf0ff7df0eb5d7d4f0754 (diff) | |
ARM: domains: switch to keeping domain value in register
Rather than modifying both the domain access control register and our
per-thread copy, modify only the domain access control register, and
use the per-thread copy to save and restore the register over context
switches. We can also avoid the explicit initialisation of the
init thread_info structure.
This allows us to avoid needing to gain access to the thread information
at the uaccess control sites.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/kernel/process.c')
| -rw-r--r-- | arch/arm/kernel/process.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index f192a2a41719..e722f9b3c9b1 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -146,10 +146,9 @@ void __show_regs(struct pt_regs *regs) buf[0] = '\0'; #ifdef CONFIG_CPU_CP15_MMU { - unsigned int transbase, dac; + unsigned int transbase, dac = get_domain(); asm("mrc p15, 0, %0, c2, c0\n\t" - "mrc p15, 0, %1, c3, c0\n" - : "=r" (transbase), "=r" (dac)); + : "=r" (transbase)); snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x", transbase, dac); } @@ -210,6 +209,14 @@ copy_thread(unsigned long clone_flags, unsigned long stack_start, memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); + /* + * Copy the initial value of the domain access control register + * from the current thread: thread->addr_limit will have been + * copied from the current thread via setup_thread_stack() in + * kernel/fork.c + */ + thread->cpu_domain = get_domain(); + if (likely(!(p->flags & PF_KTHREAD))) { *childregs = *current_pt_regs(); childregs->ARM_r0 = 0; |