From 797245f5da543074ee7db0e0516da744c89aa17f Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 18 Dec 2009 14:34:43 +0000 Subject: ARM: Convert VFP/Crunch/XscaleCP thread_release() to exit_thread() This avoids races in the VFP code where the dead thread may have state on another CPU. By moving this code to exit_thread(), we will be running as the thread, and therefore be running on the current CPU. This means that we can ensure that the only local state is accessed in the thread notifiers. Acked-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/kernel/process.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 0d96d0171c05..67304138a2ca 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -274,17 +274,18 @@ void show_regs(struct pt_regs * regs) __backtrace(); } +ATOMIC_NOTIFIER_HEAD(thread_notify_head); + +EXPORT_SYMBOL_GPL(thread_notify_head); + /* * Free current thread data structures etc.. */ void exit_thread(void) { + thread_notify(THREAD_NOTIFY_EXIT, current_thread_info()); } -ATOMIC_NOTIFIER_HEAD(thread_notify_head); - -EXPORT_SYMBOL_GPL(thread_notify_head); - void flush_thread(void) { struct thread_info *thread = current_thread_info(); @@ -299,9 +300,6 @@ void flush_thread(void) void release_thread(struct task_struct *dead_task) { - struct thread_info *thread = task_thread_info(dead_task); - - thread_notify(THREAD_NOTIFY_RELEASE, thread); } asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); -- cgit v1.2.1 From 22325525d8bb1478daddefec1b762e7882bcd515 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Fri, 8 Jan 2010 16:59:34 +0100 Subject: ARM: 5868/1: ARM: fix "BUG: using smp_processor_id() in preemptible code" Fix the following warning, which appears when the register dump for a faulting process is printed in a kernel with SMP, DEBUG_PREEMPT, and DEBUG_USER (with user_debug=31) enabled: BUG: using smp_processor_id() in preemptible [00000000] code: init/1 caller is __show_regs+0x18/0x234 Backtrace: [] (dump_backtrace+0x0/0x114) from [] (dump_stack+0x18/0x1c) r6:c781a000 r5:c0157544 r4:00000001 r3:00000000 [] (dump_stack+0x0/0x1c) from [] (debug_smp_processor_id+0xc4/0xf8) [] (debug_smp_processor_id+0x0/0xf8) from [] (__show_regs+0x18/0x234) r6:c781bfb0 r5:00000000 r4:c781bfb0 r3:00000000 [] (__show_regs+0x0/0x234) from [] (show_regs+0x40/0x50) [] (show_regs+0x0/0x50) from [] (__do_user_fault+0x5c/0xa4) r4:c781c000 r3:00000000 [] (__do_user_fault+0x0/0xa4) from [] (do_page_fault+0x1b4/0x1e4) r7:00000000 r6:00010000 r5:c781bfb0 r4:c781c000 [] (do_page_fault+0x0/0x1e4) from [] (do_DataAbort+0x3c/0xa0) [] (do_DataAbort+0x0/0xa0) from [] (ret_from_exception+0x0/0x10) Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- arch/arm/kernel/process.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 67304138a2ca..ba2adefa53f7 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -212,7 +212,8 @@ void __show_regs(struct pt_regs *regs) char buf[64]; printk("CPU: %d %s (%s %.*s)\n", - smp_processor_id(), print_tainted(), init_utsname()->release, + raw_smp_processor_id(), print_tainted(), + init_utsname()->release, (int)strcspn(init_utsname()->version, " "), init_utsname()->version); print_symbol("PC is at %s\n", instruction_pointer(regs)); -- cgit v1.2.1